Electronics in Motion and Conversion February 2015

ISSN: 1863-5598
Electronics in Motion and Conversion
ZKZ 64717
February 2015
are always
VARIS™ – the modular inverter system
Thanks to its modular and flexible design, VARIS™ offers compelling benefits.
The desired power can be easily achieved via parallel connection of the
modules. You are also free to choose your preferred cooling type. And the use
of standard components makes VARIS™ both cost-efficient and sustainable.
Talk to the House of Competence, because VARIS™ fears no comparison.
Even with your current inverter systems, right?
IGBT classes: 1200V or 1700V, up to 1400A
Parallel connection
engineered by
Air- or water-cooling
Compatible rectifier VARIS™ R
Compact and powerful with VARIS™ XT
GvA Leistungselektronik GmbH | Boehringer Straße 10 - 12 | D-68307 Mannheim
Phone +49 (0) 621/7 89 92-0 | www.gva-leistungselektronik.de | [email protected]
Welcome to the House of Competence.
Read online and search for key subjects from all articles in Bodo’s
Power Systems by going to Powerguru: www.powerguru.org
w w w. e l e c t r o n i c o n . c o m
Viewpoint ........................................................................................... 4
Technology for a Better World
Events................................................................................................. 4
News................................................................................................ 6-9
Blue Product of the Month.............................................................. 10
MOSFET Design Kit to Evaluate SiC
Guest Editorial................................................................................. 12
SiC Power Device Impact in 2015
By Jeffrey Casady, Cree
Market............................................................................................... 14
Electronics Industry Digest
By Aubrey Dunford, Europartners
Technology.................................................................................. 16-17
Frequency Response Measurement of the Plant,
Compensator and Loop of our Switch Mode Power Supply
By Dr. Ali Shirsavar, Director of Biricha Digital Power Ltd.
Scan me!
High Voltage and
Low Inductance
Our recommendation for applications where low selfinductance is to be combined with high currents or
voltages. Plenty of capacitance
(and absolutely no liquids) in flame-retardant plastic
Cover Story................................................................................. 18-22
Unlocking Digital Power
By Mark Adams, CUI
• Special coating patterns for up to 50kVDC/30kVAC Power Modules........................................................................... 24-25
The Influence of Power, Power Density and Lifetime Demands
By Dr. Martin Schulz, Infineon Technologies AG
• SINECUTTM windings with SecuMetTM metallization
• available with exceptionally low PD levels for
extended life
for exceptional current strength
• Low-inductance connection through robust terminals
IGBT Modules............................................................................. 26-28
4in1 400A/1200V Module with T-type Topology for 3-Level Applications
By Marco Honsberg and Thomas Radke, Mitsubishi Electric Europe B.V.
Sensors....................................................................................... 30-33
Angle Sensor Devices in On-Axis and Off-Axis Applications
By Allegro MicroSystems, LLC
Capacitors................................................................................... 34-37
Integration and Miniaturization Trends
By Dave Connet, Director IC Reference Design, TDK
Portable Power........................................................................... 38-40
PSU ICs use Innovative Technology to Reduce 25W Charger Cost
and BOM Count
By Mike Matthews, VP Product Development, Power Integrations Inc
Lighting....................................................................................... 42-43
A Low-Cost LED DriverModule, 0.5 A/33 V for general use,
with efficiency aboe 90%
ByValentin Kulikov, FuturoLighting
Communication Power............................................................... 44-45
FPGAs Saves Power in Data Centers
By Wolfgang Patelay, Freelance Journalist, Bodo´s Power Systems
New Products............................................................................. 46-49
More Power for the Future
By Wolfgang Patelay, Freelance Journalist, Bodo´s Power
New Products............................................................................. 50-64
ELECTRONICON Kondensatoren GmbH
· Keplerstrasse 2 · Germany - 07549 Gera
Fon: +49 365 7346 100 · email: [email protected] · web: www.electronicon.com
The Gallery
Bodo´s Power Systems®
February 2015
• Industry’slargestreference
• Over1,000powermanagement referencedesigns
• Enhancedsearchtool:Parameters,
• Directaccesstofullytestedanalog,
This robust tool offers complete
solutions across the board.
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June Hulme
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Technology for
a Better World
We all need to work hard to keep up with a
better world. Tolerance and acceptance to
others must be a mandatory human behavior. We all need to support the freedom of the
press in the world. I am shocked of the brutal
terrorism that hit “Charlie Hebdo” in Paris.
We as Engineers have to work for a better
world. Education is the main thing for our
kids to develop a better future.
The year has started and we are looking
forward to our first big conference and show
in Charlotte NC for power electronics is the
APEC. The heartbeat for any electronics is
built on a stable and reliable power supply.
APEC has the full focus set to improvement
of the power supplies and reduction of losses
in conversation. It is an international event
that has built up a long tradition.
We are now coming together to celebrate the
30th anniversary.
What happened within that time frame?
Power MOS devices became mature and
helped significant in reduction of losses.
The MOSFET and IGBT have changed a lot
and now the devices in new wide band gap
like GaN and SiC are continues improving
Infineon as a significant player in Power
Semiconductors has also put attention to
these new technologies. The purchase of
International Rectifier by Infineon gets the
GaN expertise.
Biricha Digital Power Workshop
with Microchip MCUs Karlsruhe Feb 10th
When I was a young engineer, 40 years ago,
I looked to all these semiconductor companies around the globe. By now we have seen
more and more that big players buy others.
Texas Instruments got National, Power
Integrations got CT Concept and Infineon got
International Rectifier. That is real monopoly
and not a play.
Looking out what will be next.
Communication is the only way to progress.
We delivered already two issues this year.
My contributed articles are all archived on
my web-site and also retrievable at PowerGuru. Bodo’s Power Systems serves readers
across the globe. If you speak the language,
or just want to have a look, don’t miss our
Chinese version:
My Green Power Tip for February:
Replace broken light bulbs with LED bulbs.
That has a big impact to energy reduction
and also lowers your utility bill for electricity.
Best Regards
Embedded World 2015,
Nuremberg, Germany, February 24-26
Biricha Analog and Digital PFC Workshop
with TI C2000 MCUs Garching Feb 24th
APEX 2015, San Diego, CA, Feb. 24-26
ESARS 2015, Aachen, Germany,
March 3-5 http://www.esars2015.org/
Bodo´s Power Systems®
February 2015
LF xx10
Current transducer range
Pushing Hall effect technology to new limits
To save energy, you first need to measure it! To maximise energy savings, you need to
measure the current used accurately!
By using the most advanced materials available, LEM’s new LF xx10 transducer range
breaks new ground in accuracy for Closed Loop Hall effect transducer performance.
LEM ASIC technology brings Closed Loop Hall effect transducer performance to the level of
Fluxgate transducers and provides better control and increased system efficiency, but at a
significantly lower price.
Available in 5 different sizes to work with nominal currents from 100 A to 2000 A, the LF xx10
range provides up to 4 times better global accuracy over their operating temperature range
compared to the previous generation of Closed Loop Hall effect current transducers.
Quite simply, the LF xx10 range goes beyond what were previously thought of as the limits of
Hall effect technology.
• Overall accuracy over temperature range
from 0.2 to 0.6 % of IPN
• Exceptional offset drift of 0.1 % of IPN
• Fast response time less than 0.5 μs
• Higher measuring range
• 5 compact sizes in a variety of mounting
topologies (flat or vertical)
• Immunity from external fields for your
compact design
• 100 % fully compatible vs LEM previous
• -40 to +85 °C operation
At the heart of power electronics.
Power Electronics for Distributed Generation Systems
The 6th International Symposium Aachen, Germany, 22nd to 25th of
June 2015
With the “Energiewende” (Energy Transition) towards more renewable and distributed generation in the power system ongoing, the
6th International Symposium on Power Electronics for Distributed
Generation Systems (PEDG2015) will be held from 22nd to 25th of
June 2015 in Aachen, Germany. Following on the success of the five
previous international symposia, the PEDG 2015 Symposium will
provide a venue for experts to present the state-of-the-art in power
electronics and distributed generation (DG) systems. The Symposium
is sponsored by the IEEE Power Electronics Society and organized
by the PELS Technical Committee on Sustainable Energy Systems.
PEDG 2015 will feature keynote speeches, tutorials regular technical
sessions and an Exhibition.
www.pedg2015.org Hamburg, Germany, looks forward to host the EU PVSEC 2015
The EU PVSEC 2015 will take place from 14 – 18 September 2015
at the CCH (Congress Centre Hamburg), Germany. Easy access by
international air travel, by train and by car and a superior infrastructure make Hamburg with its CCH the ideal location for the EU PVSEC
The CCH building complex allows for a compact layout of the EU
PVSEC 2015 with the Conference, Industry Exhibition and Parallel
Events located close together. This, together with the venue’s central
location in the Hamburg city, guarantees for an efficient and successful participation for all Conference Delegates, Exhibitors and Visitors.
The Call for Papers is open: Be part of this leading international
PV Conference and present your latest results to specialists and
decision-makers from around the globe. Submit your abstract by 16
February 2015!
Definitive Agreement to Acquire Arlon, LLC
Rogers Corporation announced it has signed a definitive agreement
to acquire Arlon, LLC, currently owned by Handy & Harman Ltd.
(NASDAQ: HNH), for $157 million, subject to closing and post-closing
adjustments. The transaction, which is subject to regulatory clearances, is expected to close in the first half of 2015. Rogers intends to
finance the transaction through a combination of cash and borrowings
under an existing bank credit facility.
Bruce Hoechner, President and Chief Executive Officer of Rogers
said, “This transaction is truly a unique strategic fit for both Rogers
and Arlon. We are energized by the opportunity to serve our customers with our complementary capabilities and technologies in circuit
materials and engineered silicones and to enhance value for our
shareholders. We look forward to closing this acquisition as another
significant milestone in Rogers’ growth as a premier global engineered materials solutions company.”
Arlon’s circuit materials product family positions Rogers for additional
growth in the rapidly expanding telecommunications infrastructure
sector, as well as in the automotive, aerospace and defense sectors.
Arlon produces its circuit materials in Bear, Delaware; Rancho Cucamonga, California; and Suzhou, China.
Smart Systems Integration 2015 9th European Conference & Exhibition
The event focuses on Integration Issues of Miniaturized Systems –
MEMS, NEMS, ICs and Electronic Components.
Five keynotes, 55 lectures, two special sessions by EPoSS, a panel
discussion and 30 poster presentations are offered to the participants
of Smart Systems Integration in Copenhagen, Denmark from 11 – 12
March 2015.
The conference is accompanied by an exhibition where e.g. R&D
institutes, manufactures of components and systems in the sectors
microsystems and nanotechnology, microelectronics, sensor technology and wireless communication present their products and solutions. Exhibitors meet a highly specialized, international audience of
Bodo´s Power Systems®
experts, users and scientists.
An attractive social program will complete the event. The pre-field trip
on 10 March 2015 is going to DELTA Dansk Elektronik Lys & Akustik
in Horsholm. The traditional conference dinner on 11 March 2015 is
taking place at Jacobsen Brewery & Bar and includes a guided tour
through the brewery. During the conference dinner the Best Paper
Award and Best Poster Award of SSI 2014 will be presented.
The complete conference program and further information are available at:
February 2015
Looking for a partner that moves fast,
but keeps your options open?
Then try Vincotech.
Making power modules is what we do.
Fast and agile is what we are.
Infineon Technologies AG Successfully Acquires International Rectifier
Infineon Technologies AG announced the closing of the acquisition
of International Rectifier. With effect from January 13th 2015, the
El Segundo based company has become part of Infineon following
the approval of all necessary regulatory authorities and International
Rectifier’s shareholders.
“The acquisition of International Rectifier is an important step for
Infineon to foster our position as a global market leader in power
semiconductors. We are sure that International Rectifier and its
employees will make a great contribution to a joint successful future.
Together both companies make a powerful combination”, says Dr.
Reinhard Ploss, CEO of Infineon. “We offer our customers an unparalleled product portfolio. Our profound understanding of their needs
enables us to provide the best possible and competitive solutions.
The acquisition helps us to accelerate our strategic approach ‘from
product thinking to system understanding’.”
The combined company is led by Reinhard Ploss, CEO, Arunjai Mittal,
Member of the Management Board Regions, Sales, Marketing, Strategy Development and M&A, and Dominik Asam, CFO. President of
International Rectifier and of Infineon North America is Robert LeFort.
International Rectifier is highly complementary to Infineon: the combined company gains greater scope in product portfolio and regions,
especially with small and medium enterprise customers in the US
and Asia. The merger taps additional system know-how in power
management. It expands the expertise in power semiconductors, also
combining leading knowledge in compound semiconductors, namely
Gallium Nitride. Furthermore, the acquisition will drive greater economies of scale in production, strengthening the competitiveness of the
combined company.
Jason Fullerton, Moderator for Two IPC APEX EXPO 2015 Sessions
Alpha is pleased to announce that Jason
Fullerton, Customer Technical Support
Engineer for the Americas Region, was
selected by the IPC to moderate two
technical sessions during the IPC APEX
EXPO taking place in San Diego in late
February of next year.
The first session, Fluxes I, focuses on
the makeup and performance of the flux
component of solder paste. The second
session, BGA Head in Pillow, discusses
the defects on ball grid array packages, known as Head in Pillow.
“The material presented during the technical sessions at IPC APEX
contain new research and advancements from the industry,” said Ful-
lerton. “I was thrilled when asked to moderate on the subject of fluxes
and head in pillow because I see first-hand how a lack of understanding these topics can adversely affect a customer’s assembly process.
There is a tremendous amount of value in these sessions if you can
transfer what you learn to your production floor.”
Jason has over 20 years of experience in manufacturing operations in the automotive, high-reliability, and commercial electronics
industries, specializing in SMT and wave soldering processes. He has
also worked at a failure analysis lab and IPC Training Center near his
hometown of Philadelphia. He earned his Bachelor’s Degree in Manufacturing Engineering from GMI Engineering & Management Institute
(now Kettering University) in Flint, MI.
8th Developer Forum Battery Technologies of batteryuniversity.eu
At the 8th Developer Forum Battery Technologies, participants will receive information about the latest developments and
trends regarding cell selection, battery
packaging and safety, charging technologies, power management, standardization, electromobility and stationary energy
storage systems. The Developer Forum is
organized by the batteryuniversity.eu and
takes place from March 24 to 26, 2015 in
the Stadthalle Aschaffenburg, Germany.
More than 550 international participants are expected to attend this
year’s three-day Developer Forum with around 50 high-caliber speakers from research and industry and the accompanying exhibition.
Due to the overwhelming response of previous years and ongoing
Bodo´s Power Systems®
high demand, the three-day Developer Forum again begins on March
24 with two half-day basic training seminars on the topics of “Battery Management Systems” and “Lithium-ion Battery Technologies”
offered both in German- and English-language. “The use of lithium-ion
batteries is steadily increasing in all areas of daily life. It is, therefore,
important for system developers from all kinds of different fields not
only to become familiar with the basics of this technology, but also to
keep up-to-date with the latest developments. Many of our now well
over one thousand training participants use the training seminars of
batteryuniversity.eu not only as an introduction to the topic, but also
to regularly gain a quick and comprehensive overview of the latest
materials, technologies, standards, regulations, etc.,” said Dr. Jochen
Mähliß, director of batteryuniversity.eu.
February 2015
Powervation Raises USD7M in Debt and Equity Financing
Powervation Ltd., the Intelligent Digital Power™ company, announced
it has closed a $3.0 million term debt agreement with Ares Capital
Corporation that supplements a $4 million private equity financing that
closed in the December quarter. All existing investors participated in
the equity financing, including: Scottish Equity Partners (SEP), Braemar Energy Ventures, Intel Capital, VentureTech, 4th Level Ventures,
and Semtech Corporation
The funding will be used to scale the business in response to strong
adoption of the Company’s Intelligent Digital Power™ IC products in
the cloud server, high performance computing, communications, and
power supply markets. The Company’s integrated digital control and
digital power management IC products are based on a proprietary
digital control platform which delivers best in class regulation, full
auto-tuning, dynamic performance and breakthrough flexibility. Powervation’s intelligent digital DC/DC controllers provide superior programmable power solutions to the perennial power design challenges of
efficiency, size, cost and time to market.
The funding round will also enable the company to accelerate the
development and deployment of its new digital controllers with industry leading xTune™ intelligent auto-tuning technology, and ITM™
intelligent, fast transient technology for multi-rail, multi-phase and
integrated point of load (POL) applications.
Indium10.1 Pb-Free Solder Paste at APEX
Indium Corporation will feature its new
solder paste, Indium10.1, at IPC APEX
Expo 2015 on Feb. 24 in San Diego, CA.
Indium10.1 is a Pb-free halogen-containing
solder paste with the lowest levels of voiding for QFNs, BGAs, and pads with large
ground planes.
The oxidation-inhibiting properties of
Indium10.1 provide industry-leading headin-pillow and graping resistance, with complete coalescence, even after long reflow
profiles. The exceptional soldering ability
of Indium10.1 makes it the best solution for
components with less-than-ideal solderability
and challenging RF shield metallizations.
Indium10.1 offers the lowest cost of ownership to PCB assembly manufacturers
through best-in-class printing and soldering
performance, including best-in-class print
definition and transfer efficiency, low-voiding
performance, and head-in-pillow and graping
resistance. Indium Corporation will be exhibiting at booth
With its best-in-class performance enabling heat
loss reduction, the UMOS IX helps to keep you cool.
Our DTMOS family with its compact design delivers
high efficiency and power density. So whatever your
application,Toshiba has the power to make it happen.
UMOS IX: 40V MOSFETs with RDS(on)
down to 0.85mΩ
DTMOS - low loss performance in 600V,
650V & 800V class
Smallest packaging (SMOS line-up)
SiC Diodes
Automotive MOSFETs
February 2015
Bodo´s Power Systems®
Configurable Half Bridge
Circuit Design Kit
Cree, Inc., a market leader in silicon carbide (SiC) power devices,
has introduced a new Cree MOSFET design kit that includes all of the
components needed to evaluate Cree® MOSFET and Schottky diode
performance in a configurable half bridge circuit. Quick and easy to
assemble and use, the new design kit enables comparative testing
between IGBTs and Cree MOSFETs, and provides an effective layout
example for properly driving Cree MOSFETs with minimal ringing.
Designed to assist engineers new to the higher switching speeds
of SiC devices, the kit provides easy access to critical test points,
enabling simple and accurate measurements, including VGS, VDS,
and IDS. The kit is also easily configurable to several different power
conversion topologies in buck or boost configurations. Half bridge
and three-phase configurations can be constructed and analyzed by
respectively combing two and three kits.
The design kit includes two 80mOhm, 1200V Cree MOSFETs; two
1200V, 20A Cree Schottky diodes in standard TO-247 packages;
a half bridge configured design board equipped with isolated gate
drives; power supplies; and all of the other components necessary to
assemble the power stage. The kit also includes a gate driver schematic and layout reference for a TO-247-packaged Cree MOSFET, as
well as a comprehensive user manual and sourcing sheet with basic
block diagrams and specifications.
To learn more about Cree’s new MOSFET design kit, please visit:
http://response.cree.com/choosewisely to watch a video that demonstrates the advantages of designing with Cree MOSFETs, download
the user manual and SiC reference designs, or purchase the Cree
MOSFET design kit through one of Cree’s trusted distributors.
Profit from More than 40 years experience
in general and power electronics
Design of complete or parts of SMPS, lamp ballasts, LED ps, D amplifiers, motor electronics, amplifiers,
measuring instruments, critical analog hardware. Experience with SiC and GaN. EMI expertise.
Minimum design times and favorable costs due to experience and a large stock of SMPS components.
Assistance with your own designs in any design phase. Design approvals, failure analyses,
Redesigns to weed out problems or to reduce cost.
Seminars, Articles and Books. Translations of technical and other critical texts
German - English, English - German, French - German, French - English.
Former manager of R & D / managing director in D, USA, NL, A.
Consultant and owner of an electronics design lab since 23 yrs.
140 publications resp. patent applications, inventor of
the current-mode control in SMPS (US Patent 3,742,371).
Names and business affairs of clients are kept strictly confidential.
Bodo´s Power Systems®
Lagergasse 2/6
A1030 Wien (Vienna)
February 2015
5037084 Mobile:+43-699-11835174
email: [email protected]
http:// members.aon.at/aseibt
Shut Down
Power Amplifier Self Protects
With Over Current Shut Down
The MP118FD power operational amplifier is a next generation
product design targeting industrial piezo drive applications. This
open frame design integrates several new layers of onboard circuit
protection safe guards. In addition to temperature shut down and
external shut down, the device provides a new twist that replaces
the more common over current limit functionality with the ability to
completely shut down its output drivers when put into an over current situation. This will protect the power amplifier from over stress
due to excessive current and unsafe power dissipation. Onboard
temperature monitoring circuitry, also new, enables the MP118FD to
shut down the system before any permanent damage can occur. The
MP118FD is compatible with supplies up to 200V and is capable of
10A of continuous output current, or 12A PEAK.
CC 1
© 2014 Apex Microtechnology, Inc. All rights reserved. Product information is subject to change without notice.
The Apex Microtechnology logo is a trademark of Apex Microtechnology, Inc.BPS062014
Footprint 55.8mm X 41.4mm
Power up at www.apexanalog.com/bpsmp118fd
SiC Power Device Impact
in 2015
By Paul Kierstead and Jeffrey B. Casady, Ph.D., Cree, Inc.
Current status
As 2015 begins, the power semiconductor industry has more than
10 device makers with commercially
qualified silicon carbide products,
including Schottky diodes from 600V
to 1700V in single die current ratings
from 1A to 50A. SiC MOSFETs in the
same power range have been gaining
market acceptance, with five vendors
now competing with SiC MOSFETs. In addition, most of the top
power module suppliers are offering
integrated SiC-based power modules
in several circuit configurations and
power ratings. Following years of
promise, SiC power sales have grown
past $200M in 2014 and are expected
to grow even more in 2015.
Fueling the growth are the usual
suspects--server and telecommunications power supplies and solar
inverters. However, as the portfolio of
devices and packages has expanded,
applications and new end systems are
adopting rapidly. Electric vehicle (EV)
chargers, both on-board and gridtied, are amongst the fastest growing segment adopting SiC power
devices. EV chargers adopting can be in pure EV or hybrid EV, generically grouped together as x-EV. Broad adoption is also occurring
in the industrial power space led by high-density power supplies and
converters for industrial automation, medical power, induction heating
and motor drives.
a much broader range of applications including new lower voltage
SiC MOSFETs for x-EV drive-train inverters, on-board chargers, and
grid-tied chargers in the automotive space. In 2014 a major breakthrough was demonstrated with developmental 1200V SiC MOSFETs
achieving 2.7 mΩ·cm2, a new record low (~50 percent lower than best
commercial offerings) for the planar, reliable SiC DMOS structure.
This breakthrough performance enabled a highly competitive team
selected by the United States Department of Energy (DoE) to develop, benchmark, and automotive qualify 900V, 100A SiC MOSFETs
for automotive x-EV drive-train applications by 2016. The Cree-led
team includes a top North American based automotive OEM and an
advanced module manufacturer. Similarly, a 2014 announcement by
Toyota that SiC would improve its Prius hybrid fuel efficiency up to 10
percent provides momentum for SiC in x-EV.
Developmental lower-voltage SiC MOSFETs are also being evaluated for aerospace, telecom and industrial PS, micro-grid high-power
converters, and solar inverters with input voltages < 850V. Relative to
650V Si MOSFETs below 300 mΩ, new lower voltage SiC MOSFETs
offer improved voltage margin, lower QG, flatter positive RDSON
temperature coefficient, dramatically lower output capacitance, and a
better body diode for applications which value high power density, low
losses, and rugged performance.
For medium voltage, 2.5-15kV SiC MOSFETs continue to make great
strides. Highlights include the successful demonstration of a new
3.3kV, 40A MOSFET for rail and HVDC applications, which received a
great deal of interest from selected customers in this space. At least
two SiC vendors are offering engineering samples of 3.3kV SiC die
and full-SiC modules. Odakyu Electric Railway of Japan has already
announced that they have ordered 3.3kV, 1.5kA, all-SiC power modules, and they expect energy savings of 20-36 percent, plus size and
weight savings of the main circuit to be as much as 80 percent.
What typically drives adoption is the ability to successfully make
systems cheaper and better. SiC MOSFETs (> four years in the market) and SiC diodes (>13 years in the market) often enable system
switching frequencies to be increased up to six times. With higher
frequency operation, reductions in component ratings for magnetic
and capacitor elements often enables SiC based power systems to be
shrunk dramatically. In most cases the increased frequencies have
been achieved at higher energy efficiency than the incumbent silicon
based system providing additional benefit in system thermal performance. SiC power devices often results in smaller, more reliable and
lower cost power conversion solutions. Many new SiC-based end
systems have been introduced to the market in 2014 and many more
are in production qualification entering 2015.
RDSON,SP of developmental 10 kV MOSFETs improved by 25 percent
in 2014 and are being evaluated in grid-tied solar and similar applications where the low frequency, large transformers are replaced
with solid-state transformers. One DoE program underway is aiming
to demonstrate a >100 kW grid-tied inverter from panel to grid using
this “transformer-less” SiC solid-state transformer to dramatically
lower the cost of utility solar installations. Advantages include flexible sizing of the system (no limits of transformer size), lower cabling
costs (higher voltage transmission), higher efficiency, better reliability
(fewer components) and more information sharing and control options. These benefits can be extended beyond solar applications to
numerous grid-tied power systems to allow breathtaking new options
in power distribution.
Future Development
Looking forward, we expect to see future SiC products in more applications over a broader voltage range, with significantly enhanced
performance features. Building on the success of the current SiC
MOSFET portfolio, Cree’s SiC development efforts are expanding to
With the rapid proliferation of new products aimed at different markets, we expect SiC adoption in 2015 to continue to accelerate to new
Bodo´s Power Systems®
February 2015
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Electronics Industry Digest
By Aubrey Dunford, Europartners
The total production value of electronic
systems is projected to increase 5 percent
in 2014 to $ 1.49 trillion and climb to about
$ 1.82 trillion in 2018, which represents a
compound annual growth rate (CAGR) of
5.2 percent from $ 1.41 trillion in 2013, so IC
WSTS anticipates the world semiconductor
market to show a solid growth of 9 percent
up to $ 333 billion in 2014, driven mainly
by double digit growth of Memory product
category. All other major product categories
are also forecasted to have positive growth
rates. The highest growth rates are shown
for the Memory (17.3 percent), Discretes
(12.3 percent) and Analog (10.3 percent) categories. The semiconductor market growth
will be largely driven by smartphones and
The German semiconductor market is
expected to grow by 7.2 percent to € 11.3
billion this year, so the Central Association
Electronic Components and Systems. This
will be the first time that the semiconductor
market will exceed the pre-crisis levels of
2007. For 2015, the ZVEI expects the market
to achieve a five percent growth to € 12
billion. Automotive electronics is expected to
be the largest market segment in 2014, with
a market share of 43 percent. At 4.9 billion
euros, it has the largest growth in the segments (+10 percent). Industry electronics has
replaced the technology data as the second
largest market segment in 2013. This year,
its market share will be 24.3 percent. The
European semiconductor market is expected
to increase by 6.5 percent to $ 36 billion this
year. In 2015, the European semiconductor
market could grow by over 3 percent to more
than $ 37 billion.
Infineon and UMC announced the extension
of their manufacturing partnership into power
semiconductors for automotive applications.
Bodo´s Power Systems®
SEMI projects that worldwide sales of new
semiconductor manufacturing equipment
will increase 19.3 percent to $ 38.0 billion
in 2014. In 2015, strong positive growth is
expected to continue, resulting in a global
market increase of 15.2 percent before
moderating in 2016. Wafer processing equipment, the largest product segment by dollar
value, is anticipated to increase 17.8 percent
in 2014 to total $ 29.9 billion. The market
for assembly and packaging equipment will
increase by 30.6 percent to $ 3.0 billion in
2014. The market for semiconductor test
equipment is forecast to increase by 26.5
percent, reaching $ 3.4 billion this year. For
2014, Taiwan, North America, and South Korea remain the largest spending regions. In
terms of percentage growth, SEMI forecasts
that in 2015, Europe will reach equipment
sales of $ 3.9 billion (47.9 percent increase
over 2014), Taiwan will reach $ 12.3 billion
(28.1 percent increase), and South Korea
sales will hit $ 8.0 billion (25.0 percent
2014 is undoubtedly a fruitful year for the
panel industry. In addition to the overall
increase in panel price, the four major applications (TV, monitor, notebook and tablet)
still reached a total panel shipment of
826.8 million units, showing a 2.2 percent
annual growth rate, so WitsView.
TE Connectivity officially opens its new
facility to design and manufacture highly
engineered temperature sensors in Andover,
Minnesota. The new facility will be one of
TE’s largest sensor innovation centers, with a
temperature technology center of expertise.
With its acquisition of Measurement Specialties, TE is one of the largest connectivity and
sensor companies in the world, engineering
sensor solutions that help customers transform their concepts into smart, connected
Delta Electronics announced that its 100
percent owned subsidiary Deltronics (Netherlands) will acquire Eltek for NOK 3.9 billion
($ 530 M). Established in 1971 and headquartered in Drammen, Norway, Eltek
designs power supplies and has 2,400 employees at 60 offices in almost 40 countries
February 2015
The German component distribution market
has grown by 6 percent in Q3/2014, and
the booking situation remains stable, so the
FBDi. The turn-over grew to € 741 M, and the
incoming orders rose to € 738 M. Thus, the
book-to bill-rate was exactly 1. The semiconductors grew above average with 8.1 percent
to € 510 M, their market share remains at 69
During Electronica, TTI, a specialist distributor of passive, connector, electromechanical
and discrete components, was presented
with several awards by its suppliers: From
Nichicon TTI received the award for
“Distributor of the Year EMEA 2014”. TTI
was awarded by Bourns “Distributor of the
Year Europe 2014 for Demand Discovery
and Conversion”. Kingbright presented TTI
with its “Silver Award Europe 2014”. Molex
recognized TTI with its “FY2014 European
Large Distributor of the Year” award. From
Omron TTI received the award for “2014
Demand Creation Excellence” and by 3M
TTI was awarded for “2014 Fastest Growth
in Europe”.
For the second straight year, Mouser Electronics has been named the Global e-Catalog Distributor of the Year by interconnect
manufacturer Molex. Mouser has also expanded its worldwide distribution agreement
with Analog Devices to include ADI’s recently
acquired RF and microwave products from
Hittite Microwave. Mouser also announced
the introduction of their new Motor Control
Applications site. Mouser’s new applications
site provides developers with the resources
they need to learn about the latest advances
in motor control, and the newest components
available from Mouser Electronics for building motor control systems.
This is the comprehensive power related extract from the «Electronics Industry Digest»,
the successor of The Lennox Report.
For a full subscription of the report contact:
[email protected]
or by fax 44/1494 563503.
Motor Control
Consumer Products
Power Transmission
Always first-class results:
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on the components used. When it counts, power devices from Mitsubishi
Electric are always first choice. Because, in addition to many innovations,
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therefore reliably ensure first-class results.
More information: [email protected] / www.mitsubishichips.eu
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Biricha Lecture Notes on Analog
and Digital Power Supply Design
Part 1.B Foundations: Frequency Response Measurement of the Plant,
Compensator and Loop of our Switch Mode Power Supply
By Dr Ali Shirsavar and Dr Michael Hallworth, Biricha Digital Power Ltd
In the last article we discussed Bode plots and how we can use the
information displayed on a Bode plot in order to make an assessment
of the stability of a power supply. At the end of that article we showed
a Bode plot displaying real measurement data of the loop of a power
In this article we are going to discuss how to physically make this
measurement, what you will need to do to your power supply, the
hardware required and how to connect it to your power supply. We will
also cover how to measure the plant and compensator individually.
A typical power supply is shown in Figure 1. The power supply consists of a plant, which in turn can be sub-divided into a power stage
and the PWM stage and a compensator. The output voltage is fed
into our compensator, which is implemented using an op-amp and
the appropriate selection of capacitors and resistors (much more on
compensator design in later articles). The output of our compensator
is fed into a comparator which generates our new value of duty cycle
thus closing the loop. Of course the comparator and compensator opamp are usually implemented inside our controller IC.
as our ground; therefore we must use an injection transformer as
shown in Figure 1. Then, we connect channel 1 of the Bode 100 to
point A and channel 2 to point B as shown. Channel 1 will measure
the input signal, i.e. the injected sinusoid. Channel 2 will measure
the sinusoid as it appears on the output voltage of our converter - i.e.
after it has passed through the loop. Using this configuration we will
be able to measure the open loop response of our power supply.
An easy way of working out what we are measuring is to simply
put your finger in the position of channel 1 and then follow its path
through our circuit until you get to channel 2. For example in Figure
1 we can see that we will first go through the compensator, then the
PWM and then the power stage; so we are measuring the entire loop.
We will show later in the article how this measurement can be imported in into our automated power supply design software (Biricha WDS)
Figure 2 - Measuring the frequency response of the plant
Figure 1 - Set up of a typical switched mode power supply showing
the injection resistor and measurement points, A, B and C.
Measuring the loop response
As we discussed in the first article, in order to measure the loop,
all we have to do is inject a sinusoidal signal into our system and
measure how this signal changes as it passes through the system. In
order to do this, we will break the loop by inserting an injection resistor into the feedback path of our output voltage. Figure 1 shows the
location of the injection resistor. The location is chosen such that it will
not affect the overall operation of the loop. The most common location
for the injection resistor is on the top of the compensator’s potential
divider. The value of the injection resistor should be small compared
to those of the potential divider so that it does not impact the correct
operation of our compensator - typically it is around 20Ω. Across the
injection resistor, we will inject a sinusoidal signal of varying frequencies using a network analyser. In our case we used a Bode 100 vector
network analyser from OMICRON Lab.
We cannot connect the Bode 100 directly across the injection resistor
as the potential at the bottom of the injection resistor is not the same
Bodo´s Power Systems®
Measuring the plant
It is always prudent to measure the plant to make sure that our
transfer function (much more on this in later articles) is correct and the
same as the real power supply. We can easily superimpose our measurement with our calculated transfer function using Biricha WDS. In
order to measure the plant, all we have to do is move the location of
our Bode 100’s channel 1 probe to point C as shown in Figure 2. The
injection resistor and signal that we are injecting remain the same. If
we now put our finger on channel 1 and follow it path to channel 2,
we will see that the signal goes through the PWM stage followed by
the power stage i.e. we are measuring our plant. The Bode 100 will
now compare these two signals and the resulting Bode plot will be the
measurement of the plant of our system.
Measuring the compensator
It is always important to also measure the frequency response of our
compensator to make sure that we have not made any mistakes in
our calculations and are not trying to operate the IC’s op-amp beyond
its capabilities. To measure the compensator we are interested
in seeing how the signal changes as it passes from point A in our
diagram to point C. Therefore, we should connect Channel 1 to point
A and Channel 2 to point C. This measurement will be the frequency
response of the compensator within our system and again can be
February 2015
imported into Biricha WDS so that a direct comparison can be made
with the calculated results.
Real Life Measurement
As a real life example we will now measure the loop of an analog
voltage mode controlled Buck converter. This EVM is used during
our Analog Power Supply design workshop [1] and all attendees get
hands-on practice of measuring the loop, compensator and plant of
this EVM and others during the workshop.
By connecting the Bode 100 vector network analyzer to the Buck
converter as described in the loop measurement section, we are able
to obtain the real measurement data. This data can then be imported
into Biricha WDS for comparison with our calculated results. This is
shown in Figure 4.
The black trace in Figure 4 is the measured result from the Bode 100
and the green trace is the result calculated by WDS. You can see
that we have an almost perfect match. There are also almost perfect
matches between the calculated and measured results of the plant
and the compensator, but we have not shown them here due to the
shortage of space.
In the previous article we discussed what to look for in a Bode plot in
order to assess stability. In short we are interested in the cross-over
frequency, phase margin, gain margin and the slope of the gain plot
at cross-over (please see previous article). We can clearly see these
from the Bode plot of Figure 4. However WDS also displays these
automatically in its “Stability Box”; this is shown in Figure 5.
Figure 3 - Measuring the frequency response of the compensator
You see from the above figure that not only WDS has designed a very
robust and stable power supply, in fact the real measurement is a very
close match with the designed value.
Concluding Remarks
In this article we have explained how to measure the loop, compensator and plant of your power supply using a vector network analyzer.
The measurements were made by injecting a sinusoidal of varying
frequency into the loop and measuring how this signal changed as it
passed through the system.
The connection setup for the loop, the plant and the compensator
were shown in Figures 1 to 3 respectively.
In the next article, we will be discussing transfer functions from first
principles and how you can use them to analytically design a compensator for a power supply in order to meet the stability criteria.
For the PDF version and related videos please visit:
Figure 4 - Real measurement data of the loop (black trace) imported
into WDS and compared with the simulated loop (green trace)
P.m. G.m. Slope at Fx
Nominal 11156Hz 62° 33dB-23.0dB/dec n/a
Measured 11156Hz 55° 23dB-25.3dB/dec
Figure 5 - Stability of WDS simulated (nominal) loop and real measured loop
Things to Try
1 – Check out our videos which complement this article:
2 – Visit OMICRON Lab’s website for more information about Bode 100
3 – Try out a trial version of Biricha WDS from www.biricha.com/wds
[1] Biricha Digital’s Analog Power Supply Design Workshop Manual
[2] OMICORN Lab website
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Unlocking Digital Power
This is a story of change, a story that began 5 years ago when a small power company
entered an uncertain market dominated by larger firms. Unlocking the true potential of
digital power has required an approach very different to what had traditionally existed in
the power supply industry. This company’s vision to collaborate and think creatively has
changed the way the entire industry now approaches the board mount power market.
By Mark Adams, CUI
CUI is the company that entered into the digital power market at a
time when only a few large firms dominated the space. As is typical
with any new and exciting technology, the introduction of digital power
to the market was not smooth. CUI knew that their approach to the
market had to be different because this was a very different technology compared to analog solutions of the past. The technology had the
potential to open up a range of new possibilities for system and board
level designers, but with this potential also came a perception of
complexity. CUI knew that in order for digital power to spread beyond
the large tier 1 organizations with vast in-house design resources,
they needed to take this technology and simplify it, similar to the way
the FPGA market did in the late 90’s to address a space that was
dominated by ASICs.
Up until CUI entered the market, digital power technology was primarily being implemented at a discrete semiconductor level. Power module companies were primarily focused on custom designs rather than
general market release products for two primary reasons. First, many
module companies perceived the customer support requirements
for a standardized digital module platform as too great. Second, the
digital power marketplace was in the midst of a significant lawsuit that
forced a delay in product development by numerous power supply
and semiconductor companies.
In 2005, Power One went to court versus Artesyn for a series of
patents that they had on serial bus communication within a digital
point of load (POL) device. In 2007, the courts sided with Power One,
immediately stalling the development path of many power supply
and semiconductor companies designing with the technology. When
CUI started looking at the market in early 2009, they knew that the
Power One patent for this technology was a major barrier to entry. At
the time, Power One had only licensed this patent to semiconductor
companies because they had their own interests in the point of load
space. In September of 2009, CUI and Power One announced that
they had signed a non-exclusive license agreement for their digital
power IP - a first for a power supply company. This was a major step
for the market in opening up the technology beyond a single source
solution, and representative of the way CUI would approach the market moving forward - to work collaboratively with others in an open,
transparent, and honest manner - with their customers, technology
partners, and competitors.
With the intellectual property concerns addressed, CUI began development of their first modules with the understanding that their product
was only as good as the IC technologies that they integrated. With
this in mind, CUI began to look for strategic partnerships with semiconductor companies that possessed IP that would help to simplify
implementation of digital power for the customer. Based on initial
Bodo´s Power Systems®
market feedback, one of the most complicated factors in implementing this new technology was proper compensation of the circuit.
Finalizing the circuit compensation required special tools and many
dedicated man hours. To address this, CUI partnered with Powervation; a controller company founded in 2006 out of Cork, Ireland and
backed by Intel and TSMC. Powervation had technology that would
allow for auto-compensation within the circuit, providing customers
with the means to bypass the traditional practice of building in margins to account for factors such as component ageing, manufacturing
variations, and temperature. The ability for the module to dynamically
achieve optimum stability in real time as conditions change was important to not only provide a superior product to the market, but also
to allow for the technology to be more easily adopted. In September
2009, CUI announced the industry’s first auto-compensated digital
POL modules in a push to take the technology beyond the traditional
tier 1 companies in an initiative they dubbed as “Simple Digital”.
The market began to embrace digital power technology for the value it
added to the system and the fact that it could dramatically shorten designs in the most sophisticated circuits—but this was still not a simple
transition for many customers. In the power space, “sole source” is a
dirty word. Because digital power was still a relatively new technology, multi-source options were not yet available to customers, creating another barrier to digital power’s mass adoption. To address this,
CUI and Ericsson Power Modules began talks to create a cooperation
based on a set of common footprints. For the previous 2 years, Ericsson Power Modules and CUI had competed in the same space for
the same customers. However, they also competed against the fact
that customers would not accept a single source design. Thus, in July
2011, Ericsson Power Modules and CUI announced a collaboration to
provide their customers with an alternate source for their digital power
products, an industry first.
Figure 1 – The NDM2Z Series based on an Intersil controller was the
first fully digital POL module to offer a dual source option to customers.
February 2015
Thermal Interface Material (TIM)
The Infineon-qualified solution
With the ongoing increase of power densities in power electronics the thermal interface
between power module and heatsink becomes a larger challenge. A thermal interface
material, especially developed for and pre-applied to Infineon’s modules outperforms the
general purpose materials available.
TIM does not only provide the lowest thermal resistance, it also fulfills the highest quality
standards given for power modules to achieve the longest lifetime and highest system
„ Reduced process time in manufacturing
„ Simplified mounting
„ Increased system reliability
„ Increased system lifetime
„ Optimized thermal management
„ Improved handling in case of maintenance
Tj–Tamb [K]
Main Features
„ Best in class thermal resistance
„ Pre-applied to Infineon Modules
„ Dry to the touch
„ Optimized for dedicated Infineon Modules
Time in HTS* [Weeks]
*HTS: High Temperature Storing,
Stresstest 1000 h, 125 °C
n MOD-3
n MOD-2
n MOD-1
n IFX-Solution
As part of this collaboration, CUI uncovered yet another possible
barrier to mass-adoption of digital power technology. PMBus was
established as an open standard power-management protocol. The
command language is intended to enable communication between
components of a power system: CPUs, power supplies, power
converters, and more. However, it doesn’t guarantee interoperability
between digital ICs from different manufacturers. To address traffic
issues on the main bus, semiconductor manufacturers developed
their own proprietary serial busses to alleviate the burden. The commands transferred over the secondary serial busses are not standard,
varying from vendor to vendor. If an engineer were to mix ICs from
different vendors within a digital system, it becomes imperative that
the documentation is extremely thorough. If the software platform on
a board is not accurately written, catastrophic failures could occur. For
example, in Figure 2 you will see a system with a host controller. This
controller sends out a simple Vout command to change the voltage of
each rail to 1.0 V. The data format and exponent value for each rail is
provided from 4 leading digital power IC vendors. 1.0 V is sent to the
first rail with the appropriate command, and then subsequently sent
to the other 3 power rails. In this example, the other controllers will
change output voltages anywhere from 1.6 V to 8.0 V—creating the
potential of catastrophic failure on this board. In short, a PMBus logo
does not guarantee compatibility.
Figure 2 – The same PMBus Vout command sent to 4 different digital
controllers creates 4 unique and potentially catastrophic outputs.
This is evident when you look at the transition in power supplies needed for a technology that is abundant across all markets, the FPGA.
As FPGA geometries reduce with each successive generation, so
have the core voltages and allowable voltage tolerances within the
Figure 3 – As FPGA geometries reduce with each successive generation, so have the core voltages and allowable voltage tolerances
within the device.
To address this rapidly growing challenge, CUI set out to acquire IP
that could integrate with digital control technology to better address
the lowering core voltages, rising current densities and tightening
tolerances of advanced ICs. In March 2010, CUI signed an exclusive license agreement for a SEPIC-fed buck topology that would
be branded as “Solus”. This technology would allow CUI to reach
performance levels that others could not.
CUI’s Solus® Power Topology provides advantages in isolated and
non-isolated dc-dc converter designs through a significant reduction
in switching and conductivity losses. Very simply, the Solus Topology
combines a single-ended primary-inductor converter (SEPIC) with the
conventional buck topology to form the SEPIC-fed buck converter.
Lower voltage and current stresses in the topology coupled with an
inherent GCE (gate charge extraction) process allows the new topology to reduce switching turn-on losses by 75% and switching turn-off
losses by 99% on the control FET when compared to a conventional
buck converter. Total efficiency is further increased by distributing the
energy delivery into multiple paths, reducing circuit conduction losses
by nearly 50%. The rich feature set of the Solus Topology is allowing
CUI to accelerate the performance trend trajectories for the big-four
power conversion needs in their latest designs: higher power density,
higher efficiency for “greener” systems, faster transient response, and
lower EMI.
With this revelation in hand, CUI set out to educate customers,
partners, and even competitors that interoperability was an issue
that needed to be considered and addressed in order for digital
power to propagate throughout the industry. And because the existing Powervation design could not provide a true 2nd source to the
Ericsson footprint due to the PMBus interoperability issues between
the controllers, CUI created a second POL family based on Intersil’s
digital controllers.
Since 2011, CUI has been focused on the continuation of product
development to create a platform of easy to implement digital solutions. This has never been a more daunting task as the power supply
requirements of today’s advanced designs become more complex.
The market has made a shift, in a very quick manner, to a new era
of power conversion. Simply converting one voltage to another is no
longer adequate. Now, converting one voltage to a perfect voltage,
under all conditions, all of the time is mandatory.
Bodo´s Power Systems®
Figure 4 – Solus Power Topology’s Sepic-Fed Buck design allows for
a significant reduction in switching losses compared to a standard
buck design.
February 2015
Capacitors for Power Electronics
IGBT Snubbers
RF Mica Capacitors
DC Link Capacitors
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AC Output Harmonic Filter Capacitors
In March of 2014, CUI released its first non-isolated digital POL
based on the technology. The NDM3ZS-60 was a 60A module that
delivered 20% more power in the same space as competing products,
equivalent transient performance with one-third the output capacitance of other solutions, and a reduction in power losses by almost
25% versus best in class products on the market, thus addressing the
needs brought on in today’s application – power loss, power density,
and power accuracy.
Figure 5 – CUI’s NDM3ZS-60 was the company’s first non-isolated
digital POL based on Solus Power Topology.
On top of the growing need for perfect power conversion, the capabilities of digital power are quickly moving from an “optional” to a
“required” technology thanks to the effects of Moore’s Law. As the
geometries of new semiconductors continue to drop, semiconductor manufacturers are looking for ways to increase yields and also
provide options to customers that allow them to optimize between
performance and power consumption. However, in order to achieve
this, power rails need to be digitally controlled and need to have the
capability to be adjusted dynamically with a simple command. An
example of this is Altera’s new SmartVoltage ID. In Altera’s Arria 10
FPGA, they will program an “ID” into the chip during testing that will
allow a customer to read that ID. They will then know how low they
can operate the core voltage while still meeting the performance
benchmarks of the device. The customer can then adjust their power
supply rail accordingly.
The trends driving digital power to a “required” aspect of today’s power systems are highlighted in recent forecasts from market analysts.
According to Jonathon Eykyn, Power Supply and Storage Component
Senior Analyst for IHS, digital power is now well-established in the
server and telecommunication markets. However, IHS is now starting
to see growing adoption across a much broader range of products
and applications, which is driving rapid growth. IHS expects the
market for digital power to grow 3.5-5 times between now and 2018
with the majority of the growth coming from customers outside of the
traditional server and telecom space.
Due to this accelerating market growth, CUI has recognized the need
for further collaboration in the industry to meet customer needs and
stay ahead of technology advancements. In October 2014 CUI,
Ericsson Power Modules, and Murata announced the founding of
a new power industry consortium, the Architects of Modern Power
(AMP Group). The goals of the Group go far beyond the ambitions or
achievements of established trade associations in the power industry.
The AMP Group will be characterized by deep collaboration between
its member firms in developing leading-edge digital power technology,
in terms of both functionality and efficiency. Common standards will
encompass mechanical, electrical, communications, monitoring and
control specifications. Members will focus on developing products that
deliver high efficiency power conversion under all operating conditions
and provide supply chain security to customers through true plug-andplay compatibility between their products.
Figure 7 – Architects of Modern Power was founded to be a unique,
long-term strategic consortium that will enable the power design
community to benefit from world-class technology innovation and true
plug-and-play product compatibility.
Though still a relatively new entrant into the market, CUI has recognized that the key to unlocking digital power’s true value has required
a very different way of thinking. Through collaboration with customers, vendors, and industry peers, barriers that have had the potential
to limit adoption of the technology have been broken down. Moving
forward, CUI will be a leader and a voice in the industry as the boardlevel power landscape continues to change.
CUI will be at the Applied Power Electronics Conference (APEC) in
Charlotte, NC from March 15~19 demonstrating their latest digital
products. In addition, Mark Adams will be speaking at 2 different
industry sessions, Industry session #1: PMBus Considerations for
Interoperability in a Complete Digital Power Ecosystem – as part of
the PMBus Track and Industry session #2: Multi-Sourcing Standards
for PoL and IBC Digital Power Supplies.
Figure 6 – According to IHS, the digital power market is expected to
grow 3.5 to 5 times over the next 4 years.
Bodo´s Power Systems®
February 2015
Power Semiconductor
The Influence of Power, Power Density and Lifetime Demands
In 1983, GROWIAN, the world’s largest wind energy conversion system of its era went live with
an output power of 3MW and an overall conversion efficiency of about 80%. With the absence of
suitable power electronics, the necessary energy conversion was achieved by rotating machines
consuming a tremendous amount of material, several cubic meters of space and a vast amount
of money. This way of mechanical conversion became obsolete with the introduction of modern
power semiconductors which massively increased the conversion efficiency, too. Despite the impressive capabilities they reached by today, the market demands for future generations of power
modules to be developed remain challenging.
Dr. Martin Schulz, Infineon Technologies AG
Why power density matters even in wind power plants are recognized
as huge entities. The space available to integrate the necessary subsystems is heavily limited. Inside a windmill’s nacelle, the mechanical setup consumes most of the space, especially if a gearbox adds
to the drive train’s volume. Besides the obvious space restrictions,
losses that heat up the nacelle have to be considered. Air condition is
often needed to keep the ambient temperature inside the housing at
tolerable limits during operation.
Given a system efficiency of 95% from rotor shaft to the power inverter output, 5% of losses in modern wind energy of up to 6MW need
to be handled. If, additionally, solar load at the installation site needs
to be considered, air conditioning inside the nacelle may have to cope
with up to several hundred of kW of losses generated. The basic components of a wind energy converter (WEG) are sketched in Figure 1.
DC-link capacitors. In this scenario it becomes obvious, that power
density is of utmost importance for this application.
Throughout the last decades, power semiconductors have grown in
both, current carrying capability and efficiency. Figure 2 summarizes
25 years of development in power semiconductors:
Modern power electronic converters today feature an average volumetric power density of about 1kW per liter; a converter for handling
1MW thus consumes about 1m³ of space. This includes the bare
power section with the heat sinks as well as inductors, filter- and
Figure 2: Power semiconductor development 1990-2015
The figure also includes the fact that the growth in current density
reached the factor 4. At the same time, the losses were reduced by
about 50%. As a consequence, the power loss density increases and
thus the temperatures in a given environment grow as well. At a first
glance this seems to be a drawback, as higher chip temperatures
and higher temperature swings are considered detrimental in regards
of lifetime. As a rule of thumb, an increase in chip temperature by
20K reduces the predicted lifetime of a given power semiconductor
constellation by 50%.
Figure 1: Subsystems of a wind mill showing sensors (1), communications (2), temperature control (3), pitch- and azimuth control (4), drive
train with generator (5) and power electronics (6)
Bodo´s Power Systems®
An increase in power density can only be considered positive if
the lifetime and the reliability of the application are not decreased.
Moreover, the market expectation is that power density and lifetime increase simultaneously. With this requirement, only a holistic approach
to enhance power semiconductor modules promises substantial
progress. This is especially true for the application specific overload
conditions in various modes of operation in windmills. These may lead
to short periods of time with very high peak power demand.
February 2015
To tackle the challenges described above Infineon developed the
.XT technology: a combination of new interconnection processes
and technology changes featuring the newest power semiconductors available. This new setup allows achieving higher power density
levels while even increasing the cycling capability as depicted in
Figure 3.
(P) 1.559.651.1402
VMI’s Newest, Digitally Controlled
40kV High Voltage Power Supply
Figure 3: Cycling capability comparison between IGBT4 and .XT
Keeping the same temperature levels as today, an increase in lifetime
in a range of factor 10 is achieved. Trading lifetime for output power
for the cost of higher power density, additional 25% of output power
can be gained without enlarging the current design’s cabinets. A state
of the art 6MW offshore wind mill today carries up to 12 racks with
power electronic components. The power density increase demonstrated by .XT leads to a noteworthy reductions; the same output
power can now be handled by only 10 racks.
Besides the savings in space inside the nacelle, further benefit arises
for the application. Less material is in use, less weight needs to be
shipped and a lower number of units has to be handled.
Resources spent per kW installed
System cost within energy conversion systems is a complex issue. It
is often stated that the power semiconductors contribute a noteworthy
part to the financial aspect. An increase in the power density that can
be delivered by modern power modules also influences other parts of
the overall systems. From Figure 3 it can be taken that even at higher
temperature levels, the same output power can be achieved while
keeping the lifetime.
Figure 4: New materials like copper will help in achieving high market
demands for power density, lifetime and reliability
For the designer, this leads to possible reductions in the size of cooling systems or heat sinks in use. Increasing the switching frequency
and shifting the thermal budget to switching losses in turn, allows reducing the physical size of grid filters, saving material in wound goods
as well as in grid connected filter capacitors. Eventually, inverters
based on the new power components make more efficient use of the
resources needed per kilowatt installed, thus leading to a reduction in
size, weight and – most important – in system cost.
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(P) 559.651.1402
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Dedicated to the application
Paradigms in building power electronic components have just recently
seen a transition. Traditionally, new developments were driven by new
chip technologies. After introducing a lead type, the new technology
subsequently was migrated to different power module families and
various power ranges or frame sizes. This approach became less
helpful when modern IGBT modules reached a maturity that made
other influences than bare switching behavior reach higher priority. A
rethinking took place to start improving power electronic components
as an inherent part of an overall system instead of a standalone entity.
Intense discussions about the most urgent issues were part of the
change process. Additionally, experts were asking how to eliminate
the root causes of troubles specifically related to dedicated applications. For the semiconductor manufacturer, deep system understanding was now necessary – and attained – to create a technology
platform for new generations of power devices that solve these major
issues in power electronic designs.
Future prospects
The face of power electronic components is about to change. The
most visible feature will be the replacement of aluminum materials
and surfaces by copper, new materials in interconnection technologies and ultimately new designs for power semiconductor modules.
With its .XT technology, Infineon introduced the next step in highly reliable power devices that will continue to serve a demanding market.
Besides these enhanced power semiconductor components, a new
philosophy in optimizing these parts will ensure that Infineon Power
Semiconductor remains a seal of quality and innovation.
February 2015
Bodo´s Power Systems®
4in1 400A/1200V Module
with T-type Topology
for 3-Level Applications
A growing demand for 3-level inverter technology combining reduced power loss and
increased power capacity is originating from power conversion applications like wind
and PV inverter as well as from industrial equipment such as uninterruptible power
supplies (UPS) and recently active frontends of 4-quadrant drives.
By Marco Honsberg and Thomas Radke, Mitsubishi Electric Europe B.V.
Much attention has focused on the further development of power
semiconductor modules being the key devices in inverters, that offer
low power consumption, reduced package size and especially low
inductance to help maximizing the 3-level inverter’s performance.
Mitsubishi Electric launched the CM400ST-24S1 IGBT, e.g. a 4in1
400A/1200V IGBT module as part of a new family of power semiconductor modules optimized for 3-level inverters to meet these demands
by adopting new packages that help reducing inductance, thereby
contributing to reduced power consumption and downsizing in largecapacity industrial equipment.
Module ratings
This new 400A/1200V module represents the biggest current rating of
a planned lineup of 4in1 3-level IGBT modules planned in the same
package. Based on electrical and thermal evaluations the CM400ST24S1 is supposed to operate in 125kW-class inverters.
The photo of the CM400ST-24S1 reveals the outline of the package
and figure 2 indicates the drawing of this new package. With baseplate dimensions of 115mm x 82mm and the innovative step terminal
design this new outline provides new degrees of freedom in designing a power stage including the mechanical design of a gate driver
Printed Circuit Board and an efficient utilization of the heatsink in case
of parallel connection of modules. The next paragraph will introduce
the design features that have led to such an innovative IGBT module
packaging concept.
Figure 1: Photo of CM400ST-24S1
Figure 3: Design considerations for 3-level modules
Design considerations for the CM400ST-24S1
Figure 3 shows at a glance the design considerations that have significantly influenced the concept of this new IGBT module CM400ST24S1. In fact a state-of-the-art 3-level IGBT module shall reflect a best
adoption of design aspects as shown in figure 3 to deliver the desired
Figure 2:
Outline drawing
Bodo´s Power Systems®
Chip performance IGBT / Di
Obviously the chip performance itself of the IGBTs and Diodes play
one major role in the design of a 3-level IGBT module. In case of the
CM400ST-24S1 the latest chip generation of Carrier Stored Trench
February 2015
SEMiX® 5
Enhanced Standard for Superior
Thermal and Dynamic Performances
Up to 350kVA
Superior dynamic performance
Optimised thermal performance
Competitive and wide product range
Easy and solder-less assembly
Baseplate solution
Press-Fit Technology and screw power terminals
gate Bipolar Transistors (CSTBT™) have been adopted. Thus, for
1200V blocking voltage class a 6.1st generation CSTBT™ chip has
been selected offering today’s best trade-off between switching and
conduction loss in this voltage class along with 650V CSTBT™ chip
of the 7th generation chip technology for the first time introduced in an
industrial grade IGBT module. Figure 4 shows the innovative 7th generation chip technology which has improved trade-off between static
loss Vce(sat) and dynamic loss as specific turn off energy E(off).
inductance for at least those two commutation paths. The CM400ST24S1 has reached for both mentioned 3-level commutation loops
stray inductance levels of less than 30nH (approximately 26nH) and
additionally a commutation stray inductance of about 30nH in the
2-level commutation path from terminal “P” to terminal “N”. The balanced low stray inductance layout of this new package incorporates a
new degree of freedom to alter from 3-level commutation strategy to a
2-level commutation operation providing a better thermal exploitation
of the semiconductor chips at high current and low modulation indices
to cover for example extraordinary operating conditions of uninterruptible Power Supplies (UPS).
Chip size and thermal resistance (Rth)
The CM400ST-24S1 employs Silicon – Nitride substrate (Si3N4) to
provide the required thermal performance of the package. This material’s thermal conductivity is in between the superior performance of
the Aluminum Nitride (ALN) and the worse performing Aluminum oxide (Al2O3). Referring to the topology as shown in figure 5 the thermal
performance of each chip could be optimized for certain applications.
Hence, an anti-paralleled Di to Tr1 or Tr4 could be sized comparatively small for a motor drive application operating at high power factor
but they should be sized much bigger for a module placed in an active
frontend mainly operating in Power factor Correction (PFC) mode. Indeed the CM400ST-24S1 chip size ratio has been selected to satisfy
both applications.
Figure 4: 7th generation chip technology
In this 7th generation 650V chip substantial modifications of the fabrication technology have led to a significant performance improvement.
The manufacturing techniques applied to this novel 650V CSTBT™
allowed an about half-size shrinkage of the transistor unit cell through
a fine pattern process and a LPT (Light Punch Through) structure
utilizing an advanced thin wafer process technology.
For DC-link voltage
ranges up to about
850V a so called “Ttype” topology has
proven to be the
best choice considering the switching
frequency range of
the application. The
CM400ST-24S1 is
made for DC-link
voltages of up to
850V and is following this topology
indicated in figure 5
utilizing the aforementioned 6.1st
Figure 5: “T-type” topology
generation CSTBT™
1200V class IGBT
and anti-paralleled diodes for Tr1 and Tr4 and the novel 650V 7th
generation CSTBT™ chips with anti-paralleled diode for Tr2 and Tr3.
Paralleling capability
Paralleling capability is an essential feature of the CM400ST-24S1,
since it permits utilizing the same module for a modular design for
output power requirements of more than the mentioned 125kW. Providing paralleling as dedicated feature implies constructing the module in order to minimize the distance between DC-link terminals of the
paralleled modules and to provide a (simple) layout that utilizes the
heatsink area and blower construction efficiently. The module dimensions of 82mm x 115mm, whereas the shorter 82mm is the dimension
that advantageously decreases the distance between two adjacent
modules efficiently. The step terminal approach for the output terminal
simplifies the connection to parallel modules while this different height
level will refrain from disturbing the DC-link construction of terminals
“P”, “C” and “N”.
The CM400ST-24S1 has been designed to provide a high performing low inductive IGBT module solution for 3-level applications with a
maximum DC-link voltage of 850V. The innovative package construction realizes low inductance in all possible commutation loops and by
the step terminal it is dedicated for paralleling application for active
frontend (PFC) as well as for PV and UPS output application. The
low thermal resistance along with the loss performance of the latest
generation of utilized IGBT and diode chips provides unprecedented
output power performance of a 3-level IGBT module in this configuration. The first module that is available is a 400A class current rated
module. A further lineup of smaller current ratings is planned.
Stray inductance
The module’s internal stray inductance in conjunction with the
blocking voltage capability of the chosen chips their dynamic loss
performance and the desired performance of the module are key
optimization objectives. Referring to the complexity of potential current and commutation paths of a T-type 3-level IGBT module, e.g. at
least from terminal “P” to terminal “C” and from terminal “C” to “N” in
a typical 3L commutation loop the module design must minimize the
Bodo´s Power Systems®
February 2015
[email protected]
[email protected]
Angle Sensor Devices in On-Axis
and Off-Axis Applications
This article provides a basic under- standing of how Allegro’s precision Circular Vertical
Hall based angle sensor integrated circuits are used in on-axis and off-axis applications.
Allegro MicroSystems, LLC
Hall based angle position sensor ICs are increasingly preferred over
other Hall and non-Hall based sensor solutions for position monitoring
applications. They are particularly sought after in automotive and industrial markets. Specific automotive applications for precision angle
sensor ICs include, but are not limited to, wheel and motor position in
electronic power steering and braking systems, transmission systems
(PRNDL, clutch, inhibitor switch), windshield wipers, turbo charger
exhaust gate valves, accelerator and brake pedals, and fuel tank
level sensing. Similarly, in the industrial market, angle sensor ICs are
sought after for motor control, valve, lever and joystick applications.
There are a number of key factors on why the demand for Hall based
angle position sensor ICs has grown so rapidly in recent years. First,
the level of accuracy available with Hall based angle sensor ICs has
improved dramatically in recent years. Today’s Hall based angle sensor ICs can now measure angles from 0º to 360º, with an accuracy
of less than 1º, or <0.3%. Both linear position Hall sensor ICs and
some non-Hall based sensor ICs cannot match this level of accuracy
Second, the measurement of an angular position provides system
level cost savings over other sensor technologies. Instead of having
to measure a long stroke displacement using one or more traditional
linear position Hall sensor ICs and a complicated mechanical assembly, many applications today can instead use a single angle sensor
and cheaper mechanical assembly to accomplish the same task. And
again, with an angle sensor they can do so with better accuracy. In
many cases a simple puck magnet attached to the end of a rotating shaft and placed in close proximity to an angle sensor is all that
is required to obtain accurate position information of a mechanical
component in a system.
Lastly, Hall based angle sensor ICs can accurately measure magnets
rotating at very high rates of speed.
In this application note, I describe and demonstrate the use of Circular
Vertical Hall (CVH) technology based angle sensor ICs in several onaxis (end-of-shaft) and off-axis (side-shaft) applications.
Circular Vertical Hall Technology Overview
Unlike other angle sensor technologies that employ orthogonal Hall
plates (with or without concentrators) or magnetoresistive elements
to measure target magnetic field amplitudes, CVH technology utilizes
a circular Hall element with a ring of electrical contacts to measure
the target magnetic field and produce a single channel front-end
output. The front-end output’s phase relationship, after being digitally
processed, is then compared relative to an internal reference signal to
produce an angle measurement.
Bodo´s Power Systems®
The actual CVH ring structure is monolithically and inseparably integrated into the silicon along with the backend digital signal processing functions and interface circuitry. There are no unique processes
required to fabricate a CVH based sensor IC. It is constructed by
implanting X vertical contact elements (e.g. 64) in a ring shaped Nchannel well. Due to the vertical contact elements, CVH based angle
sensor ICs measure planar fields emanating out from an interface
Other competitive angle sensor technologies produce two front-end
outputs from two separate Hall element or magnetoresistive sensor element channels. These front end signals are then processed
through a CORDIC algorithm to produce an angular output. With this
type of approach, performance and accuracy issues arise when the
two channels are mismatched either in channel offset or sensitivity.
Additionally, if either of these channel output signals saturate, then the
output signal will exhibit large errors. Saturation can occur when there
is air gap variation between the target magnet and the angle sensor
CVH based angle sensor ICs on the other hand are much less affected by these types of channel mismatch issues. Since a single
front-end channel is produced by the CVH ring there are no mismatch
concerns. And since the CVH front-end channel’s phase, instead of
amplitude, is compared to an internal reference signal, field level saturation is not a concern. Moreover, since the CVH based angle sensor
doesn’t measure magnetic field amplitudes it provides high levels of
air gap independence.
Shown in Figure 1 is a representation of a target magnet placed over
a CVH ring structure. Again, it is important to note that the CVH ring is
actually part of the angle sensor silicon die.
With the magnet stationary over the CVH ring, the angle sensor
digitally switches between groups of CVH ring contact elements to
effectively create an array of miniature Hall plates.
Figure 1: Target Magnet Field Placed Over a CVH Ring Structure
February 2015
In total, 64Miniature Hall plates, in this
example, are dynamically constructed and
measured during one full electronic rotation
of the CVH ring. The result is a coarse sine
wave that constitutes output voltage from
each of the contact elements in the CVH
The coarse sine wave is then passed
through a series of filters to produce a
smooth sine wave. The smooth sine wave
is then processed through a zero crossing
comparator. The phase of the
IC. Its “zero crossing point” is then compared
to an internal reference signal’s “zero crossing” point. The phase difference between
the two zero crossing points represents the
angle measurement of the target magnet.
Due to the fact that the digital switching
between the 64 contact elements can be
performed at very high speeds, refresh rates
as fast as 25 µs can be achieved. As a result,
CVH based angle
sensor ICs can produce highly accurate angle measurements even on target magnets
rotating at very high RPM rates. The only issue with increasing target magnetic rotational
rates is an increasing lag factor relative to
where the target magnet is actually located
over the CVH ring, and when the angle last
measured is transmit- ted out of the device.
However, with a steady rotational velocity or
a rotational speed calculation algorithm in
the system micro- processor that interpolates
“zero crossing point” is proportional to the
phase or vector direction of the external
magnetic field sensed by the angle sensor
IGBT IPMs (Intelligent Power Modules)
n High Integration n High Flexibility n High-Efficiency
ROHM Semiconductor´s Intelligent Power Modules combine several components like
gate drivers, bootstrap diodes, IGBTs or Power MOSFETs (PrestoMOSTM), fly wheel
diodes as well as various protection functions within one compact package.
Figure 2: On-Axis Angle Sensing
Figure 3: Typical On-Axis EPS Application
Key Features
• Package includes: IGBT, FWD,
bootstrap diode and gate driver
• Full Protection Circuits (Short Circuit,
Under Voltage, Thermal Shutdown)
and Fault Signal Output
• Various range of currents available
(1.5A, 2.5A, 10A, 15A, 20A, 30A)
• Motor Drives for appliances and
consumer electronics
(e.g. AC Air compressors)
• Motor Drivers for VRMS,
AC =100V-240V
• Motor Control for White Goods
• Low Power Industrial Motor Control
Bodo´s Power Systems®
February 2015
Technology for you
Sense it
Light it
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between at least 2 angle data points from the angle sensor IC, this lag
factor can easily be accounted for at the system timing level.
Use of CVH based Angle Sensor ICs in an On-Axis Application
On-axis angle sensing is the most common type of angular position
measurement application. It involves measuring the displacement of
a rotationally moving magnet that is commonly placed on the end of a
shaft or underneath a gear (see Figure 2).
Compared to off-axis applications, on-axis angle measurements
yield higher accuracy results and require less digital post processIng
such as harmonic linearization. However, the attachment of button
magnets to a shaft (for example a motor shaft), typically used in onaxis applications, creates mechanical mounting and EPS Module cost
challenges. Mounting a magnet on the end of a shaft often involves
the use of non-ferromagnetic fixtures (i.e. brass) to hold the magnet
in place. Despite the cost of the brass fixture, on-axis sensing is common in most motor position applications.
Figure 3 shows a typical on-axis Electronic Power Steering (EPS)
application configuration. In the EPS sensing module, along with two
linear position sensor ICs for measuring handwheel torque, there
resides a Hall based angle sensor IC for measuring steering wheel
rotational position. The angle sensor IC is positioned underneath a
puck magnet that is fastened into the underside of a spur gear. The
top surface of the angle sensor IC and the puck magnet are separated by a small air gap with minimal tolerance variation. Typically the
airgap is in the range of 1 mm to 3 mm. The smaller the air gap the
stronger the magnetic field presented to the angle sensor IC, which
results in better angle measurement and improved accuracy over a
wider temperature range.
As Figure 4 illustrates, the smaller the air gap, the stronger the field
level presented to the surface of the angle sensor IC, and the more
accurate the angle measurement.
Figure 4: Changes in Peak Angle Error Over Air Gap Variations Relative to a 1.76 mm Air Gap with 900 G Field
Use of CVH based Angle Sensor ICs in an Off-Axis Application
Off-axis angle sensing is another common type of angular posi- tion
measurement application. It involves an angle sensor IC measuring
the angular position of a magnetic field generated by a ring magnet
that is attached around a shaft. As observed in Figure 5, the angle
sensor IC is located adjacent to the shaft and ring magnet. As the
shaft and ring magnet turn, the angle sensor IC measures the resulting angle position.
Figure 6: A1332 Harmonic Linearization Results
Figure 5: Location of Angle Sensor IC
Figure 7: A1332 Harmonic Linearization Results
Bodo´s Power Systems®
One major issue with off-axis angle sensing is that a wide variation in
magnetic field orientation and strength is observed by the angle sensor IC as the magnet and shaft rotate. As a result, the angle sensor
IC requires significantly more digital post processing of the raw angle
measurement to achieve an accurate final angle measurement output.
February 2015
The additional post processing adds cost and
complexity to the angle sensor integrated
circuit, and typically does not produce the
same level of angle accuracy measurement
as an on-axis angle measurement system.
This said, mounting a ring magnet around a
shaft is usually less complex and lower cost
to produce than an on-axis angle measurement system.
As shown in Figure 6, the raw angle
measurement (described in the figure as prelinearization or Pre Lin) observed by Allegro
MicroSystems’ A1332 angle sensor positioned in an off-axis orientation, is non-linear
and does not meet the required accuracy of
many target applications. In this particular
application the raw angle error measured is
≈ +10º to -14º. Post processing, however,
of the raw angle measurement with such
techniques as harmonic linearization can
dramatically reduce the angle error output
from the angle sensor IC.
As observed in Figure 7, the raw input angle
error measurement, similar to what is shown
in Figure 6 and indicated by the black line,
is dramatically reduced after performing
harmonic linearization on it. (see Post Lin
The raw angle error observed by the magnetic sensor IC in an
off-axis application can be reduced by
increasing the strength and uniformity of the
ring magnet. The field strength that the sensor IC sees can be further improved by positioning the angle sensor IC closer to the ring
magnet, however mechanical tolerances of
the system (e.g. run-out of the rotating shaft)
can limit how close the angle sensor IC can
be positioned next to the ring magnet.
Arc Magnets in Off-Axis Applications
Arc magnets can also be used in off-axis
angle measurements, as shown in Figure
8 below, for “Short Stroke” applications. In
short stroke applications the shaft does not
rotate a full 360º. As depicted in Figure 8,
the arc magnet is located on only one half of
a circular plate that is attached to a rotating
shaft. Since the application doesn’t require
a full rotation of the shaft, the cost of the
magnet and the overall sensor system can
be reduced.
Short stroke off-axis angular sensor systems,
however, usually require the same level
of additional post signal processing as full
stroke/ring magnet off-axis applications.
Figure 8: Arc Magnet in Off-Axis Application
Hall based sensor integrated circuits have
proven to be preferred sensing solutions
for harsh automotive and industrial environments. They are rugged, highly reliable,
contactless, and can effectively “see through”
non-ferrous materials. As such, they are
insensitive to dust, dirt and humidity often
found in harsh environments.
Allegro MicroSystems’ CVH based angle
sensor ICs offer all of the same benefits of
their Hall based predecessor devices, but
with improved accuracy and speed, and support for a wider array of harsh and demanding sensing applications. They also offer
unmatched precision and repeatability, and
are more immune to air gap variations that
can cause magnetic field saturation in other
Hall based ICs. Moreover, with integrated
features, such as linearization, extensive
on-chip diagnostics, and redundancy package options, Allegro’s MicroSystems’ angle
sensor ICs are ideal for automotive and
industrial safety critical applications.
Although CVH based angle sensor ICs are
designed as standard
off-the-shelf devices, magnetic sensor
subassemblies and systems are complex
and require careful magnetic and mechanical system design. This application note only
touches upon the various factors that need
to be considered when designing a magnetic
based sensor system.
For more information please contact:
Michael Doogue, Business Unit Director,
Advanced Sensor Technologies:
[email protected]
February 2015
Bodo´s Power Systems®
Integration and
Miniaturization Trends
Passive embedding for performance and reliability
Thanks to new materials and integration technologies the embedding and integration of
passive components is making great advances. New miniaturized components designed
specifically for embedding enable even more compact and reliable systems.
By Dave Connet, Director IC Reference Design, TDK
The dimensions of passive components and their ruggedness for further processing often determine whether they are suitable for specific
embedding and integration technologies. TDK has developed innovative capacitors and thermistors and employs state-of-the-art integration technologies that enable superior passive embedding solutions.
Embedding capacitors in IGBT modules
Traditionally, IGBT modules in the mid power range and based on Si
and SiC technologies employ external snubber capacitors. Until now,
it was not possible to embed these components and thus shorten the
long leads that are afflicted with parasitic inductances. Irrespective of
their dimensions, conventional capacitors are insufficiently resistant
to the heat involved in the direct assembly of the IGBT module. In
addition, some have only a low capacitance per volume and suffer
considerable loss of capacitance at high rated voltages.
at 150 °C. As a result, this prevents the feared uncontrolled thermal
runaway from occurring. Its parasitic effects are also very low: ESR is
only 50 mΩ at 100 kHz and drops to only 10 mΩ at 1 MHz, resulting
in very low losses. The ESR declines even further as the temperature
rises: at 85 °C it is already less than 20 percent of its original value at
25 °C. This results in charge and discharge times of between 25 ns
and 30 ns. The ESL of CeraLink capacitors is below 5 nH, making this
technology particularly suitable for fast-switching inverters.
All these advantages make CeraLink technology predestined to
be embedded in IGBT modules as snubber capacitors. Two SMD
types with rated voltages of 500 V DC are available for this purpose
(Figure 2). The low-profile 1 µF variant with dimensions of only
4.35 mm × 7.85 mm × 10.84 mm and the 5 µF type with dimensions
of 13.25 mm × 14.26 mm × 9.35 mm are particularly compact and
may be placed very close to the semiconductor with negligible ESL.
Now, with the EPCOS CeraLink™, a completely new kind of capacitor
has been developed that suffers none of these drawbacks. CeraLink
technology is based on the ceramic material PLZT (lead lanthanum
zirconate titanate). In contrast to conventional ceramic capacitors,
CeraLink has its maximum capacitance at the application voltage, and
this even increases proportionately to the share of the ripple voltage
(Figure 1).
Figure 2: EPCOS SMD CeraLink for integration in IGBT modules.
The CeraLink low-profile 1 µF variant (left) and the 5 µF type (right)
are designed for embedding in IGBT modules. They feature compact
dimensions and can withstand high temperatures of up to 150 °C.
Embedding temperature protection in IGBT modules
IGBT modules in inverters achieve the highest possible efficiency
when they are operated at their upper temperature limit. Thus, exact
monitoring of the operating temperature is required in order to prevent
damage to the semiconductors. The suitability of standard SMD NTC
thermistors used for this purpose up until now, however, is rather limited because they are not compatible with all semiconductor assembly
processes. In particular, these include high-temperature soldering and
silver sintering under pressure.
Figure 1: Capacitance of the EPCOS CeraLink as a function of
voltage. In contrast to other capacitor technologies, the effective capacitance of the EPCOS CeraLink rises with increasing voltage. The
impact of the ripple voltage amplifies this effect additionally.
Another advantage is its high insulation resistance. The RC time constant τ is 70 000 ΩF at 25 °C and this value drops only slightly even
Bodo´s Power Systems®
In order to solve this problem, a wafer-based manufacturing process
for EPCOS chip NTC thermistors was developed (Figure 3). The new
components are now able to withstand the thermal and mechanical
stresses encountered during assembly. Moreover, they save space
because they need no special pads for soldering to the semiconductor substrate.
February 2015
A key advantage of the NTC thermistors manufactured from wafers
is the configuration of their electrical contacts. In this case, they are
located on the top and bottom surfaces of the chip. This allows the
lower terminal to be contacted directly and with complete surface contact onto the semiconductor substrate using conventional semiconductor processes. The upper terminal is contacted via conventional
wire bonding, as is usual for IGBT modules. The contact surfaces are
optionally available in gold or silver plating in order to achieve the best
possible bonding results.
Figure 3: Wafer and EPCOS NTC thermistor with contacts on the
top and bottom surfaces. Complete EPCOS NTC wafer with carrier
(left) and an individual NTC chip (right). The flat contact areas are on
the top and bottom surfaces, rather than on the sides, which is more
Among the other advantages of these chip NTC thermistors are their
minimal electrical and thermal tolerances. This precision is achieved
by means of a special process technology: Before separating the
individual elements from the wafer, the total resistance of the wafer is
measured with respect to a rated temperature of
100 °C. The size of the thermistors to be separated is then determined based on this. This ensures that the tolerances of the separate
components is much smaller than those of standard NTC thermistors
rated at 25 °C, as is shown in Figure 4.
3D integration with LTCC and SESUB
As smartphones and other portable electronic devices are designed
to support more bands and offer greater functionality, a maximum
level of integration that goes beyond the miniaturization of the single
components is required in order to keep these devices compact.
LTCC technology (low temperature co-fired ceramic) is an established
technology that enables the functions of passive components such as
inductors, capacitors and resistors to be embedded within the thin ceramic layers. Depending on the level of integration, LTTC technology,
which is used mainly to manufacture RF modules for smartphones,
can save up 80 percent space compared with discrete solutions.
However, because the LTTC sintering process takes place at temperatures higher than 500 °C, heat-sensitive components such as
semiconductors must be mounted in piggyback mode on the upper
side of the modules after sintering. By actually embedding the ICs in
the substrate, TDK’s SESUB technology (semiconductor embedded in
substrate) represents a new approach to integration. Even including
the embedded ICs, the overall thickness of the SESUB substrate is
only 300 µm, (Figure 5).
Figure 5: Cross-section through a TDK SESUB substrate. The four
micro-structured substrate layers are only 300 µm thick – including of
all connections and vias. Even ICs with numerous fine-pitch I/Os can
be embedded into the TDK SESUB substrate. The discrete passive
components required can be placed on the surface of the substrate.
The discrete passive components required can be placed on the
surface of the substrate. In order to increase the integration density
even further, thin passive components will also be embedded in the
substrate in a next step. Because SESUB modules make use of the
third dimension, their area is 50 to 60 percent smaller than conventional discrete solutions, depending on the design.
Figure 4: Comparing the precision of NTC technologies. In the temperature range of around 120 °C, which is critical for semiconductors,
the chip NTC thermistor has a high measurement accuracy of ±1.5 K.
In contrast, the standard type rated at 25 °C exhibits a relatively large
tolerance of >±5 K.
Because EPCOS chip NTC thermistors have a narrow tolerance of
only ±1.5 K at 100 °C, IGBT modules can then be operated without
premature derating at temperatures very close to their maximum
permissible values and thus be utilized more efficiently. This solution
is also suitable for new power semiconductor generations such as
those based on SiC.
Bodo´s Power Systems®
The shorter line connections within the substrate layers of the
modules lead to improved parasitics and thus support better system
performance. EMC performance is also improved due to the shielding
effect of the metal layers inside the SESUB substrate. In addition,
SESUB delivers excellent thermal attributes due to the fact that the
IC is completely embedded. All surfaces of the chip are in full contact
with the laminate, which optimizes the heat transfer from the semiconductor into the substrate layers. These layers themselves contain
the copper micro-interconnection grids, which provide for a very
homogenous and efficient heat dissipation. In particular, their superior
thermal performance is important for applications in the area of power
management, transceivers, processors, and the power amplifier – or
all the main components of a smartphone. In addition to miniaturization, a key criteria for the use of both LTCC and SESUB technologies
are their high reliability and significantly reduced logistics outlay.
A typical example of a SESUB design is the extremely compact TDK
Bluetooth 4.0 low energy module, developed for the Bluetooth 4.0
low energy (LE) specification, which is being marketed as Bluetooth
February 2015
Smart (Figure 6 left). With a footprint of only 4.6 × 5.6 mm2 and a low
insertion height of 1 mm, the new SESUB-PAN-T2541 Bluetooth 4.0
LE module sets the industry benchmark for Bluetooth Smart modules. The module is also very well suited for use in wearable devices
thanks to its compact size.
Figure 6: Space-saving TDK SESUB module. Left: The TDK Bluetooth low energy module worldwide, developed for the Bluetooth 4.0
low-energy unit with dimensions of only 4.6 mm x 5.6 mm. The complete power management of a smartphone is integrated in the TDK
power management unit (right).
SESUB is also highly suitable for handling the power management
in smartphones. In the TDK power management unit (PMU) module
(Figure 6 right), the IC for managing the power supply was embedded
directly into the substrate for the first time. This innovative step allows
manufacturers of end equipment to reduce their development costs
and times still further. In combination with newly developed capacitors and power inductors in SMD versions, the module dimensions
are only 11.0 mm x 11.0 mm x 1.6 mm. They also contain a highly
efficient power supply for the buck converter in a 5-channel configuration with an output current of up to 2.6 A as well as low-noise, high
PSRR (power supply rejection ratio) low dropout regulators for up to
23 channels and an extremely efficient charge circuit for lithium-ion
rechargeable batteries.
Utilizing the integration potentials of PC boards
Multilayer PC boards have long ceased to be merely carriers of components. In order to utilize their integration potentials more efficiently,
TDK is working jointly with industry partners on the further development of technologies for embedding active and passive electronic
other things,
the integra<< Table 1: TDK
series for
in PCBs
tion technologies, which play a critical role in the implementation of
to be driven forward.
Type miniaturized modules, isCUA2
Especially the MLCCs that are needed in nearly every circuit for buffMax. capacitance [µF]
ering and noise suppression offer significant potential for integration
((BILD s.u.))
thus miniaturization. TDK has
the MLCC-CU series,
1.0 Unlike conventional MLCCs,
be embedded in PCBs.
Width [mm]
directly into the laminate layers of the PC boards. These MLCCs are
Max. insertion height [mm]
0.11 to 0.25
0.11 to 0.25
distinguished by their very low insertion heights, which, depending on
Terminal width [µm]
the type, are between 0.11 mm and 0.25 mm (Table 1).
Table 1: TDK MLCC-CU series for embedding in PCBs
Author  Epcos_Table 1.docx
PSU ICs use Innovative
Technology to Reduce 25W
Charger Cost and BOM Count
Using new Fluxlink safety-isolated communication technology, InnoSwitch ICs combine
primary- and secondary-switcher circuitry to reduce component count, eliminate slow and
unreliable optocouplers, outperform primary-side controllers and slash manufacturing
costs of power supply designs.
By Mike Matthews, VP Product Development, Power Integrations Inc
Manufacturers of smart mobile devices, set-top boxes, networking
equipment and computer peripherals are constantly challenged to develop low-cost, efficient adapters and chargers that meet increasinglydemanding energy consumption regulations. Flyback designs using
primary-side regulation (PSR) techniques are often used because of
their simplicity and cost. However, more accurate control is delivered
by secondary-side regulation (SSR); such designs are also less sensitive to production tolerances in the transformer and other external
The major issue with all PSR solutions is that it is only possible to
see what is happening on the output after switching the primary-side
transistor: effectively, every time the transistor switches you get a
glimpse of the power supply output load conditions. However, high
energy efficiency requirements demand that the switching frequency
is reduced at light loads, therefore these ‘glimpses’ become less
frequent, compromising the ability of the power supply to respond to
fast transient loads. The system is always playing catch up, inevitably
leading to system compromises.
A further disadvantage with PSR controllers is that they infer what is
happening on the power supply output from waveforms on the primary
bias winding of the transformer – rather than directly measuring output voltage and current. This means that transformer manufacturing
tolerances, along with primary clamp circuit design, become factors
that must be ‘allowed for’ during development and mass production.
Figure 1: Magnetic coupling between the primary and secondary side
is created without the need for high permeability magnetic cores. Full
internal galvanic isolation is achieved, meeting UL, TÜV and all other
global safety standards, while external pin-to-pin creepage of over
9.5mm is achieved with a custom surface-mount package
Bodo´s Power Systems®
Transformers are infamous for manufacturing variances, complicating the management of high-volume production with PSR solutions,
ultimately impacting cost effectiveness if yields suffer.
Let’s now look at secondary-side regulation, which requires an
isolated feedback mechanism –commonly an optocoupler - which
increases circuit complexity and cost. Reliability can also be compromised if low-cost optocouplers are used as these devices suffer from
aging, temperature drift and varying current gain. Another approach
is to use capacitive coupling techniques. Capacitors themselves
are inexpensive, but they are also difficult to integrate. High-voltage
capacitive coupling on a single die is expensive to build in, especially
when it is necessary to meet the typical 6kV high-potential isolation required during testing for AC/DC power supplies. But perhaps
the most serious challenge that is raised by the use of capacitive feedback is coping with system ESD pulses. In many modern
consumer electronic specifications, such pulses can exceed +/-15kV
and are applied directly at the output of the power supply, giving rise
to capacitive currents through the isolation barrier that can damage
control circuitry. Also, common-mode effects due to voltage fluctuations can cause problems that require extra circuitry – and associated
design and BOM costs. The third approach used to implement SSR
of a power supply is to use a pulse transformer. Magnetic coupling is
extensively used in high-end communications products, but has – until
now – been prohibitively expensive for low-cost charger/adapters.
Leading power IC company Power Integrations took a long, hard look
at the problem and with its new InnoSwitch family of highly integrated
switcher ICs has come up with a digital magnetic communications
function – termed FluxLink – within the IC package at virtually no
extra cost. Effectively, a magnetic coupling between the primary and
secondary side is created without the need for high permeability
magnetic cores, using only the standard bill of materials for the manufacture of the IC package (figure 1). Full internal galvanic isolation –
exceeding that used in most optocouplers – is achieved, meeting UL,
TÜV and all other global safety standards, while external pin-to-pin
creepage of over 9.5mm is achieved with a custom surface-mount
package, designed for this application. Furthermore, by occupying the
space on the PCB normally reserved for the primary to secondary isolation region, the InnoSwitch IC essentially takes no PCB area. In fact,
the package and pin-out are designed so that the most convenient
location in most layouts is directly underneath the power transformer,
making compact layout very simple for space saving and PCB cost
reduction. The design allows for simple resistor divider direct sensing
February 2015
The perfect place
to do business
See you at HUSUM Wind!
15 – 18 September 2015 in Husum, Germany
d now
in co-operation with
Partners of HUSUM Wind 2015
of the power supply output voltage while the power supply output current measurement is fully integrated inside the package, eliminating
external current sense circuitry altogether.
Secondary sensing brings several other benefits. As well as eliminating the often unreliable optocoupler, it enables a simple transformer to
be specified since the circuit will not be sensitive to the bias winding
location or transformer inductance tolerances. Switching frequency
jitter effectively spreads the EMI spectrum, enabling designs using only standard magnetic-wire primary and Triple Insulated Wire
(TIW) secondary windings without the need for copper shields. But
perhaps the most significant benefit of InnoSwitch ICs is the provision of simple and rugged synchronous rectification – resulting in high
efficiency – without the usually expected cost penalty. Synchronous
rectification (SR) improves efficiency by replacing lossy diodes with
power MOSFETs on the output of the power supply. The voltage drop
of a standard diode is typically between 0.7V and 1.7V, but even
high-efficiency Schottky diodes will typically exhibit a voltage drop of
0.4 – 0.5V, which in a 5V system, such as a USB charger, represents
a 10% loss in the output stage.
Figure 2: Switching frequency jitter effectively spreads the EMI spectrum, enabling designs using only standard magnetic-wire primary
and Triple Insulated Wire (TIW) secondary windings without the need
for copper shields
By contrast, MOSFETs can be specified with an on-resistance as low
as 10 mOhm. Therefore in a typical charger design, the voltage drop
might be 50mV, representing a loss of only 1% – ten times less than
with Schottkys. The latest SR power MOSFETs are even 20 – 40%
cheaper than Schottkys, so SR seems to be the obvious approach for
flyback topology power supplies. However, anyone who has designed
a flyback with SR will be aware that timing is key. Simultaneous
conduction of primary transistor and SR FET creates an effective
short-circuit condition across the primary transformer winding which
usually leads to primary transistor damage. On the other hand, a
delay in turning on the SR FET once the primary transistor has turned
off compromises efficiency. In traditional SR solutions, the need for
a separate secondary-side controller to drive the SR FET also adds
cost and complexity to the circuit, which is why SR has sometimes
had the reputation of being an expensive luxury.
This is all set to change. With InnoSwitch ICs, the FluxLink element
introduces precise cycle-by-cycle, digital communication controlling
both the primary transistor and secondary SR FET switch timing.
For the first time, users therefore have a truly fool-proof SR solution
where the complete operation is integrated in a single IC rather than
having to wrestle with the independent operation of separate primary
and secondary controllers normally required in SR solutions with optocoupled SSR or PSR power supplies. In addition, the instantaneous
communication afforded by FluxLink technology allows the secondary
controller to determine the optimum turn-on and turn-off times of the
Bodo´s Power Systems®
SR FET across the entire load range, whether the power supply is
operating in discontinuous mode, continuous mode, and even under
fault conditions. This optimized SR function allows Innoswitch ICs to
easily comply with even the most stringent future efficiency standards
such as the California Energy Commission, European Union Code of
Conduct Tier 2 and DoE6.
A further benefit of the instantaneous FluxLink communication is extremely fast-transient response. As can be seen in figure 2, if an event
happens on the output, the primary side will receive a signal to turn on
within a single switching cycle period (<10µsecs),virtually eliminating
output voltage undershoot, even for 0 - 100% load transients. This
allows output capacitor values to be reduced compared to PSR solutions where the slow response to transients typically requires large
capacitors to meet the transient energy requirements.
Figure 3: A typical 2.5A, 5V mobile device charger can be achieved
using just 30 components, roughly 33% fewer than equivalent performance solutions
InnoSwitch power-supply ICs include the high-voltage power MOSFET, primary- and secondary-side controllers, FluxLink feedback link
and an integrated synchronous rectifier (SR) controller within a single,
safety-rated, 16-pin eSOP surface-mount package. Devices feature
highly accurate CV and CC control (+/-3% and +/-5% respectively)
and low ripple. Operating efficiency is typically better than 84% in a
5V output 10 watt power supply at full load (as high as 88% in higher
output voltage designs) – even higher under medium-load conditions – and no-load consumption is below 10 mW. InnoSwitch ICs
start up using bias current drawn from a high-voltage current source
connected to the Drain pin, eliminating the need for external start-up
components; an external bias winding reduces no-load and increases
system efficiency during normal operation. The ICs also include comprehensive system-level safety features such as output over-voltage
protection, overload power limiting, hysteretic thermal protection and
frequency jitter to reduce EMI.
A typical 2.5A, 5V mobile device charger can be achieved using just
30 components, roughly 33% fewer than equivalent performance solutions. And as smart mobile devices become larger, they will require
higher currents for fast charging. Where previously the idea of 5V/4A
chargers would have raised eyebrows, now such devices are starting
to appear. InnoSwitch ICs facilitate highly efficient, cost-effective
charger designs up to 25W and are designed to be compatible with
emerging rapid charge technologies, easily justifying the claim to be
the most effective and efficient means of implementing flyback power
supply designs.
February 2015
3rd International Conference on
Electrical Systems for Aircraft,
Railway, Ship propulsion and
Road Vehicles
Aachen - Germany
march 3-5
A Low-Cost LED Driver
Module, 0.5 A/33 V
For general use, with efficiency
above 90%
This article describes a simple constant
current driver module with fast PWM input
that can be used for driving mid and high
power LEDs.
By Valentin Kulikov, FuturoLighting
This module operates from 8V to 33V and the output current can be
configured from 0.1 to 0.5A in several steps. Component selection is
presented for design implementation.
Topology: Buck
Regulation, Hysteretic
Input voltage: 8-33 VDC
Output current: 100-500 mA
Switching frequency: 1 MHz max
Current ratio: 0.13 Ohm / 1 A
Dimensions: 16 x 16 x 5.5 mm
(0.63 x 0.63 x 0.22 in)
Weight: 1.6 g
-Thermal shutdown
-Current protection
-PWM up to 20kHz
Hysteretic regulation, as outlined in [1] is summarized as: the internal
switch of the TS19376 driver connects the input voltage to the load
through inductor L1. Current through the inductor linearly increases
and is monitored as the voltage drop on (R1 II R2 II R3). Once
the voltage drop reaches 149.5 mV (130 mV + Vcsn_hys (15% =
19.5 mV)), the integrated switch turns off and current flowing through
inductor and D1 linearly decreases until it drops down to 110.5 mV
(130mV – Vcsn_hys (15% = 19.5 mV)), when the switch turns on
again. This process repeats in cycle as shown in Figure 2.
The switching frequency is given by output current (ILED), input voltage (Vcc), output voltage and L1 value.
Short description
The LED driver module (Figure 1) utilizes the buck driver IC, TS19376
in the SOT89-5 package, as produced by Taiwan Semiconductor. This
buck driver involves hysteretic regulation, thus it reach relatively high
efficiencies, above 90%, without need for compensation. Output current is set by a combination of parallel R1-R3 (Figure1) with the ratio
0.13 Ohm/1 A.
Figure 1: LED driver schematic
Bodo´s Power Systems®
Figure 2: Current and voltage waveform at switching node (oscilloscope GND connected to Vcc)
February 2015
PWM dimming
The average LED current can be controlled by the PWM signal. This
type is popular and easily implemented through the MCU or by other
techniques, such as a 555 timer. A PWM signal is connected to the
PWM input of the module and accepts logical values Lo <0.3 V, Hi >
2 V (CMOS). The TS19376 accepts relatively high PWM frequencies
and therefore it is not a problem to realize fast PWM dimming with
more than 8 bit resolution.
The PWM input has a pull-up resistor, therefore once the PWM input
of the module is unconnected, ILED reaches the maximum current
value. Recommended PWM frequency is above 100Hz, because of
visible flickering.
Figure 3 LED Driver module connection
Practical realization
The TS19376 requires
a cooling, such as is
formed by the cooper
layer on the back side
of the PCB, thermally
connected with top
side through vias. A
low ESR input capacitor is required to suppress current spikes
during driver switching.
The recommended
value for C1 is 4.7 to
100 uF and dielectric
material should be
chosen from X7R, X5R
or better. C1 must be
placed as close as
possible to the IO1
supply pads.
The optimal range of
the L1 inductance is
47 -120 uH, where lower inductance is more appropriate for higher
currents and higher inductances are more appropriate for lower currents, in order to eliminate switching delay. Placement of the components should follow normal design rules to obtain the lowest switching loop, in order to minimize EMI. The start of the inductor winding
should be connected to switching node (SW pad of IO1) as well.
D1 was selected to keep leakage current low at the highest expected
operational temperature, and a low trr. D1 Forward voltage influences
efficiency and a lower Vf results in higher efficiency and lower heat
It is recommended to use a 30% margin for maximum forward diode
current as compared to ILED. In this case, SS16 (1A / 60V), from
Taiwan Semiconductor, was selected.
C2 capacitor suppress output current ripple, where its higher capacity
results in lower ripple and lower PWM frequency. It should be noted
that the value of C2 influences maximum PWM frequency.
The TS19376 includes thermal shutdown. Once die temperature
reaches 150°C, the driver is disabled until temperature drops below
115°C. This protection is useful to prevent burning of the module
PCB. The driver module can be attached to a heat-sink by two-sided
thermo-conductive tape (e.g. Bergquist Bond Ply). It is possible to ex-
tend the driver module with an EMI filter and reverse protection (e.g.
a P-MOS switch), but this depends on specific application requirements. The Driver module is populated on double-sided FR4 PCB,
with 1 mm thickness and dimensions of 16x16 mm.
Dhis LED driver has numerous applications, from driving of mid and
high power LEDs, through battery charging and others where a constant current source is required. The number of LEDs in a serial string
is determined from minimum allowed input voltage (Vcc). As can be
seen from Fig.4, close VLED string to Vcc offers higher efficiency. For
example for Vcc=12V, 3xLED in series is a good choice (VLEDF~3V).
All measurements were acquired on an automatized measurement
equipment at room temperature.
This LED driver module, with selectable output current from 0.1 to
0.5 A, is available for purchase through the FuturoLighting store [2].
The TS19376 and diode SS16 can be purchased in MOQ from Microdis Electronics [3], authorized distributor of Taiwan Semiconductor.
At conclusion, I would like to thank Mr. Bilik from Wurth Elektronik and
Mr. Reguli from Microdis Electronics for their great support on this
TS19376,Taiwan semi
4u7/50V (X7R, SMD 1210)
1uF/50V (X7R, SMD1206)
SS16, Taiwan semi
Wurth 74404064101
0.39 Ohm (SMD 0805)
FuturoLighting 376, Rev.O
[3] http://www.microdis.net/
February 2015
Bodo´s Power Systems®
FPGAs Saves Power in Data Centers
The growing use of web services and the emerging trend to the Internet of Things (IoT)
creates big data which has to be handled in data centers. But huge server farms waste
a lot of power which again increases cost. A power saving solution is the combination of
CPU and FPGAs enabling cluster computing in which FPGAs are used for parallel
computing tasks and the CPU acts as the host. This leads to massive savings in power
and therefore cost.
By Wolfgang Patelay, Freelance Journalist, Bodo´s Power Systems
In over 30 years since its formation Altera developed itself to one of
the largest global leaders in programmable semiconductors providing leading FPGA (field programmable gate arrays), SoC (Systems
on Chip) and CPLD technologies. The company, headquartered in
Silicon Valley engages today approx. 3,000 employees in 20 countries
around the world and has revenue of $1.73 billion with 70% gross
margin in the fastest growing industry segment. The company generates 41% of its revenue in the telecomm and wireless market, 22%
in the industrial, automotive, military market, 19% in the networking,
computer, storage market, and 18% in other industries. By far the
largest market by region is Asia/Pacific with 40% share of revenue,
followed by EMEA with 26%, Japan 18%, and North America 16%.
These figures prove the importance of the European market for Altera.
Efforts focused on strategic markets
The global activities of the company are
well accepted: according to Forbes it is
“one of the world´s 100 most innovative
companies” and it ranks as one of the
“Silicon Valley Top 50 Companies”. Altera
concentrates its innovative efforts into six
strategic vertical markets namely Wireless Communication, Optical Transport
Networks (OTN), Compute & Storage,
Automotive, Industrial and Military. In
Figure 1: John Daane:
these markets the company enables the
„Modern high perforusers to cope with the general trends in
mance FPGAs are suited the semiconductor industry: increasing
for many various applica- development costs, greater need for diftions and show very good ferentiation, limitless need for bandwidth,
power efficiency”
and stringent system power requirements.
According to John Daane, President,
CEO & Chairman of Altera, is the success
of FPGAs based on the fact that this
technology combines the highly flexible software programmability of general
processors with the highly efficient and
power efficient hardware acceleration of
application specific devices. This “silicon
convergence” results in high performance
devices due to the hardware programmability of integrated virtual microprocessors,
DSPs, ASICs, and ASSPs. This yields in
Figure 2: Jeff Waters:
turn in great flexibility, what means that
“Data center applications just one of these SoCs is suited for many
are the fastest growing
various applications and has very good
market for Altera”
power efficiency.
Bodo´s Power Systems®
Compute & Storage is fastest growing market segment
According to Jeff Waters, Senior Vice President and General
Manager, Business Units, is Compute & Storage the fastest growing market segment for Altera. He claims that his company is the #1
FPGA supplier in this market and its growth is driven by the trends
to big data, software-defined data centers, and cloud computing. To
confirm these trends he presented a diagram of the global data center
IP traffic growth from Cisco Global Cloud Index which shows a 25%
GAGR between 2012 and 2017. In 2012 the global data center IP
traffic was 2.6 Zettabytes/year and is expected to reach 7.7 ZB/year
in 2017. To cope with this increased data traffic network acceleration
is paramount which includes minimizing memory bottlenecks and
lower latency. Furthermore power and cooling has to be managed and
CPUs has to be off-loaded to reduce power consumption. Accelerated
access to data is also necessary to enable fast data analytics and
data mining. Nowadays data centers are faced with the following challenges: CPU architectures are inefficient for most parallel computing
applications in data centers like big data and search functions which
leads to excessive power consumption. CPU bottlenecks are starving the CPU for data which results in slow performance due to high
latency. And there is also the bottleneck to the memory which makes
the situation even worst. The market reacts to these challenges with
customized hardware and architectures but this does not result in
desired standardized solutions.
To overcome the problems with traditional data center architectures a
new approach of software defined data centers is emerging in which
FPGAs plays a major role. First of all the combination of CPU and
FPGAs enables cluster computing in which the clusters are interconnected via fast interfaces. FPGAs are used for parallel computing
tasks and the CPU acts as the host. Due to virtualisation of computation storage, networking resource sharing is realised as well as accelerated access to data. Due to the hypervisor offload the network and
used algorithms are also accelerated. This leads to the situation that
the systems in the data center will be operated workload optimised in
an infrastructure which is software defined and in which analytics will
be pervasive.
FPGAs can greatly enhance CPU-based data center processing by
accelerating algorithms and minimizing bottlenecks. Waters highlights,
that the Altera Arria 10 FPGAs and SoCs achieve a more than tenfold
increase in performance per watt. This results from the massive parallel architecture of the device which has 10 to 100 times the number of
computations units compared to CPUs. Furthermore FPGAs enables
pipelined designs that perform multiple / different instructions in a
single clock cycle and the better localized memory avoid bottlenecks.
The programmability of FPGAs enables also application-specific ac-
February 2015
celerators. Altera performed an internal performance per watt benchmark which proved the advantages of FPGAs in typical data center
applications. In this benchmark an Altera FPGA accelerator was
compared against an Intel Xeon W3690 and an nVidia Tesla (C2075)
device. In the search application of unstructured data including analytics the FPGA accelerator achieved a 10 times better performance /
power in MT/sec/W (million terms per second and watt) compared to
the competing devices. In
the image scaling application it showed a 9 times
better performance/power
measured in frames/
sec/W. The greatest
improvement by 25 times
was made in the financial
modelling application
where the devices had
to perform option pricing,
Monte Carlo simulation and Heston models
measured in MSIM/sec
(Million simulations per
second). And Waters
could also announce
a first real application:
Microsoft uses Altera FPGAs in its Catapult board
to speed up web services.
Figure 3: Stratix V FPGA on the Microsoft The use of FPGAs delivers 2 times faster Bing
Catapult board
search results and therefore the deployment of FPGAs in Microsoft data centers will start in
2015. Microsoft is convinced that FPGAs can not only speed up Bing
searches but also change the way the company runs all sorts of other
online services.
International Conference and Exhibition
on Integration Issues of Miniaturized Systems
– MEMS, NEMS, ICs and Electronic Components
Copenhagen, Denmark,
11 – 12 March 2015
Knowledge exchange
Trends and innovations
Main conference topics:
Smart energy systems
Smart Medtech systems
Smart production
System integration and packaging
More inntfoegrram
OpenCL makes FPGAs “programmer-friendly”
Bringing performance and power efficiency of FPGAs to system
programmers Altera favours OpenCL, a programming language optimized for the use of FPGAs. Up to date most electronic systems consisting of hardware and software are developed in easy to implement
C-based code for software and HDL code for hardware which allows
for the best performance per watt. OpenCL combines both of these
advantages. Today OpenCL achieved a great impact on data centers
because 4 of the 6 largest server suppliers und 3 of the top 5 largest
investment banks are developing and evaluating Altera FPGAs and
OpenCL for their future applications. Therefore Waters is expecting
that about 50% of all Altera data center business opportunities will use
OpenCL by 2016. Today the FPGA supplier collaborates already with
Baidu, a Chinese web services company, on cloud search acceleration with FPGAs and OpenCL and meets the complex requirements of
the Chinese company regarding search, big data and deep learning.
Therefore Waters believes that OpenCL is a game changer and will
help FPGAs penetrate the mainstream heterogeneous computing
world in data centers. With its high-speed FPGAs and OpenCL Altera
is well positioned to meet software defined data center requirements
and therefore software defined data centers are an expanding market
and as already mentioned the fastest growing segment for the company.
Part of the activities of:
+49 711 61946-16
[email protected]
More Power for the Future
In October and November 2014 a variety of electronic exhibitions were organised in
Germany and therefore a multitude of new products were introduced as well. This article
features a short selection of new power related products introduced at theses exhibitions
which are available immediately to the market.
By Wolfgang Patelay, Freelance Journalist, Bodo´s Power
Low-Peak Upgrade Program for Circuit Protection
Eaton announced the introduction of the new Bussmann Low-Peak
Upgrade program. The program is a complimentary service and is
focused on generating customized inventory consolidation recommendations. Eaton’s team of experts first conducts a full audit of the
customer’s fuse inventory. This audit collects all necessary data to be
analyzed (part number, description, manufacturer, quantity on hand,
and bin location). Next, the company takes the data gathered during
this audit and conducts a thorough analysis, which generates an
inventory and consolidation summary report. The report includes SKU
reduction recommendations and estimated savings, a recommended
inventory list and a quote for the purchase of new Low-Peak fuses.
Eaton’s Bussmann series Low-Peak fuses include a current-limitation
feature, helping to ensure reduced arc flash hazards. They also offer
50 percent more protection than any other Underwriters Laboratories
(UL) listed fuse. Should customers wish to purchase Low-Peak fuses
recommended by the audit and analysis, Eaton provides environmentally-friendly disposal of old inventory and a training module so that
customers can implement a seamless transition of circuit protection
Bipolar power modules in solder bond technology
Infineon Technologies Bipolar launched bipolar power modules in
solder bond technology to address the specific requirements of
cost-effective applications. With these new PowerBlock modules the
company expands its already comprehensive power module portfolio
which, so far, was only using pressure contacts. With market prices
of approximately 25 percent (depending on module/application) less
than related pressure contact variants solder bond modules offer
significant cost advantages in modules with smaller packages sizes of
up to 50mm. The new PowerBlock modules are available in package
types with base plate widths of 20mm, 34mm or 50mm. For each
package five module types for easy rectifier designs (2 x Thyristor/
PowerBlock solder bond modules are available in package types with
base plate widths of 20mm, 34mm or 50mm
Bodo´s Power Systems®
Thyristor TT, 2 x Thyristor/Diode TD and 1 x Diode/Diode DD) are offered. Infineon is covering the main current ratings per package size;
all types are available with 1600V blocking voltage. The PowerBlock
modules with isolated copper base plate provide a lower transient
thermal resistance than modules using only a DCB substrate for heat
transfer to the heat sink. This leads to higher robustness in case of
overload. The optimized housing and cover construction of the PowerBlock solder modules provide a very low torsion during screwing
of the main terminals while the modules offer best in class soldering
quality. In addition the modules show lowest power dissipation which
leads to high system efficiency.
Prewired Rack for High-Power DC Applications
Keysight introduced
a rack system for
high-power DC
applications. The
prewired N8900
Series reduces
system complexity
and saves time for
engineers designing
and implementing
high-power systems
for challenging applications requiring
up to 90kW. When
engineers design
high-power racks,
they face system design, debugging and
safety challenges
associated with high
voltages. The N8900
Series rack system
helps engineers
easily overcome
these challenges
for voltages up to
1500V and currents
up to 3060A, allowing them to focus on
Rack system enables single-output power suptheir core business
ply that delivers up to 90kW
objectives. The new
rack system allows users to install up to six 15-kW N8900 Series
autoranging DC power supplies in a parallel configuration that can
deliver up to 90kW and up to 3060 amps.
February 2015
Autoranging capability allows users to get full-power output at a wide
range of voltages. The rack system’s internal communications wiring
allows users to treat the entire rack as a single power supply that delivers up to 90kW. Engineers can communicate with the rack through
one master power supply with communications to the individual power
supplies being handled within the rack. Users can communicate with
the N8900 Series rack system via LAN (LXI Core), USB or GPIB interfaces, all of which come standard with the system.
EMI field as well as a solution for the “power analysis” area. The test
system consists of special PC software, an oscilloscope, as well as a
current probe and a voltage probe for connection with the test object.
There are three areas of measurements implemented in the software:
Software for testing switching power supplies
Rigol has released a new PC Software, which enables users to perform standard measurements on switching power supplies. This software, in combination with Rigol oscilloscopes (series DS/MSO2000A,
DS4000 or DS6000) allows customers to set up small test systems,
which represent a reasonably priced alternative for measuring
switching power supply parameters during the development phase.
Switching power supplies are commonly used in both, the electronics
and consumer industry. For example, you will find switched power
supplies in TVs, computers, halogen illuminations and in many other
consumer devices. Various parameters of these power supplies have
to be measured and compared with limits during the development
and also during the production phase. All built-in switching power
supplies must be tested and have to be compliant with the European
standard IEC61000-3-2. Similar to the EMI testing (CISPR-Norm)
there is also a split between pre-compliance test (mostly during the
development phase) und compliance test (Certification). Rigol is now
able to offer a very competitive pre-compliance test solution for the
Ultra power-analyzer software implements three areas of measurements
1. Measurements at the input: power quality, harmonics (IEC61000-32), and In-rush current. 2. Measurements at the „switch“: switch loss,
save operating area, and modulation. 3. Measurements at the output:
output analysis of the switching power supply.
February 2015
Bodo´s Power Systems®
International Exhibition with Workshops
on Electromagnetic Compatibility (EMC)
Stuttgart, Germany, 24 – 26 March 2015
Take the chance to step into the European market!
Safe the date and come to Germany to be part
of Europe's marketplace for electromagnetic
Intelligent power modules for high-performance switching
Rohm Semiconductor unveiled its new IPM (Intelligent Power Module)
family for power-efficient motor driving and inverter applications.
Based on its experience with power devices the new module series
includes IGBT based modules optimized for low or high speed operation as well as MOSFET based IPMs which incorporates proprietary
Low Ron SuperJunction MOSFET (PrestoMOS).This offers developers of white goods and industry motors a multitude of cost-efficient
design options. The full line-up includes 10A, 15A and 20A versions
of 600V IGBT-IPM. Applications with built-in motor drives demand
compactness, high integration and reliability and have to operate in
rugged environments for a long time. In response to this ROHM has
developed this highly functional IPM series based which combine
several components like gate drivers, bootstrap diodes, IGBTs or
Power MOSFETs (PrestoMOS), fly wheel diodes as well as various
protection functions within one compact HSDIP25 package.
Devices feature proprietary isolation and advanced energy-saving
characteristics for embedded motor driving and inverters
It leverages a number of proprietary technologies and material
enhancements to facilitate current surveillance, heat dissipation and
reliable operation. It significantly reduces power loss at light and
heavy loads while increasing power capability. Featuring an innovative aluminium-based Silicon-on-isolator (SOI) technology, the module
provides enhanced high-voltage capacity, high heat conductivity and
low leak current and, at the same time, prevents latch-up. For excellent reliability, the IC additionally features a comprehensive range of
protection attributes such as a current limit for the bootstrap diode,
under voltage lock-out for floating supply, fault output, thermal shutdown and short circuit protection as well as a FWD (IGBT version) to
eliminate flyback. Designers can choose from different set-ups – with
integrated IGBT or MOSFET - in order to identify the ideal solution for
their application and save time and costs.
Further information:
web: e - emc.com
phone: + 49 711 61946 63
email: [email protected]
Ruggedized power inductors for automotive
TDK/Epcos has developed a new series of rugged power inductors
for use in automotive electronics. The CLF6045NI-D wirewound SMD
power inductors feature high efficiency and reliability over a very wide
temperature range extending from -55°C to +150°C and offer rated
inductance values from 1.0μH to 470μH (E6 series). Measuring in
at 6.3x6.0x4.5mm, the CLF6045NI-D types are available for rated
currents of 0.28A to 6.7A and offer DC resistance values ranging
from 1.1mΩ to 1.30Ω. Mass production will be launched in February
2015. The new products are qualified to AEC-Q200, and thus fulfil the
rigorous requirements of the automotive industry. Thanks to advanced
materials technology the new components feature outstanding
CWT Mini Ad Quarter Oct'14.1.3.qxp_Layout 1 16/10/2014 12:58 Page 1
30MHz screened Rogowski probes
measure faster rise-times
heat resistance. A new bonding process for the terminals enables
a solderless structural design that features improved mechanical
strength. The fully automated manufacturing process ensures the
high reliability and quality of these components. As a result, the new
inductors are suitable for use in applications in demanding automotive environments such as the power supply circuits of engine control
modules (ECM) and ECUs for airbags, ABS, and headlights. In addition to the 6 mm square form factor, TDK will subsequently introduce
5 mm, 7 mm, 10 mm and 12.5 mm square types, in order to offer a
broad lineup of power inductors that is suitable for a wide range of
The new CWT MiniHF is an AC current probe featuring:
• Novel electrostatic shielded Rogowski coil
provides excellent immunity to interference from fast local
dV/dt transients or large 50/60Hz voltages
• Extended (-3dB) high frequency bandwidth
30MHz for a 100mm coil
• Peak dl/dt capability up to 100kA/µs
• Wide operating temperature from -40 to +125°C
• Thin 4.5mm Rogowski coil with 5kV peak insulation
• Zero insertion impedance
Please contact us
to discuss your
Inductors in solderless structural design with improved mechanical
strength and high reliability
Integrated DrMOS power stages deliver high power density
Vishay introduced a new family of VRPower integrated DrMOS power
stage solutions in three PowerPAK package sizes to meet the various
design challenges in high-power and high-performance multiphase
POL applications. The Siliconix SiC789 and the SiC788 are offered
in the MLP66-40L with an Intel 4.0 DrMOS Standard (6mm by 6mm)
footprint, while the SiC620 and the SiC620R are offered in the new
5mm by 5mm MLP55-31L package and the SiC521 is available in
the 4.5mm by 3.5mm MLP4535-22L. The devices are optimized for
on-board DC/DC converters in computing and storage equipment,
telecom switches and routers, graphics cards, and bitcoin mining
hardware with high current requirements and limited board space.
[email protected]
Tel: +44 (0)115 946 9657
Power Electronic Measurements
The 6mm by 6mm package of the SiC789 and SiC788 offers an easy
upgrade path to higher output power in designs already using the
Intel standard DrMOS 4.0 footprint, while the new 5mm by 5mm and
3.5mm by 4.5mm footprints are ideal for new designs where board
space constraints require more compact voltage regulators. The
PowerPAK MLP55-31L and MLP4535-22L also feature several design
enhancements that bolster the dynamic performance of state-of-the
art Vishay Gen IV MOSFETs by improving package parasitics and
thermals. For example, the SiC620R in a dual side cooling MLP5531L delivers 70A and 95% efficiency in typical multiphase buck
converter designs. The ability to cool the device from both the top
and bottom of the package results in 20% lower losses compared
to the previous-generation package while shrinking the footprint by
33%. In notebook designs and for peripheral rails in servers, telecom
switches, and gaming motherboards, the compact 3.5mm by 4.5mm
SiC521 delivers continuous current up to 25A and peak current to
40A. The VRPower family gate driver IC is compatible with a wide
range of PWM controllers and supports tri-state PWM logic of 5V and
3.3V. In addition, the driver IC incorporates diode emulation mode
circuitry to improve light-load efficiency, while an adaptive dead time
control helps to further improve efficiency at all load points. Protection features for the devices include undervoltage lockout (UVLO),
shoot-through protection, and a thermal warning feature that alerts
the system in case of an excessive junction temperature.
DrMOS power stage solutions meet the various design challenges in
high-power and high-performance multiphase POL applications
February 2015
Bodo´s Power Systems®
Play Key Role in Testing Electric Bikes
Test instruments supplied by Yokogawa are playing a key role in the
final testing of motors for electric bikes manufactured by Heinzmann
in the village of Schönau in Germany’s Black Forest region.
Heinzmann has been developing and manufacturing electric drives for
over 30 years. The company’s drives are used in a range of industrial
applications as well as in various types of electric vehicles.
The first products for electric bikes were introduced by the company in
1994 and one of its great successes was the development of motors
for the cargo bikes used by the German mail carrier Deutsche Post
This particular application uses mainly DC hub motors with gearing to ensure a high torque during acceleration. However, in electric
bikes for leisure purposes, Heinzmann installs brushless synchronous
disk motors. These are not only maintenance-free, but distinguish
themselves compared to a conventional electric motor by being based
on a flat design which offers the benefits of small size and low weight.
In addition, these motors offer high efficiency and quiet running. They
can be used in both front- and rear-wheel drive systems, and can also
facilitate energy recovery during braking or downhill running.
A full Heinzmann electric bike drive system includes the electric motor, a controller, a battery pack, a torque sensor in the bottom bracket
and a display/control unit on the handlebars. Heinzmann delivers
the drive systems to various bicycle manufacturers, but they are also
available as a retrofit kit and can also be incorporated into customers’
own electric bikes.
Engine assembly and final test
In Schönau the disk motors are assembled and a functional test
is carried out. At the test stand the assembled motor is fixed into a
mount, the power and sensor cables are connected and the motor shaft is connected via an adapter coupling and torque shaft to a
brake motor. The operator then scans the identification label which is
fixed to the motor. On the basis of the type of motor, the test system
retrieves the appropriate motor data from a database and determines
the respective test parameters and limits for the individual tests.
For each motor a high-voltage test and power measurements are
performed in the idle state and under load conditions, allowing the
efficiency of the motor to be calculated from the measured values.
Short-circuit tests are also carried out at random. In the event of
failure, the test is immediately aborted and an error log is produced.
Following each faultless run, a test label is printed. All measured data,
along with the serial number of the motor, are stored in a database to
ensure traceability.
The test rig was completely designed and produced to Heinzmann’s
specifications by ETU. It includes, among other things, a Yokogawa
WT1800 power analyser, a programmable DC power supply for voltages up to 80 V and currents up to 60 A, a high-voltage tester and a
measuring range extension for the power analyser with three current
transformers. The interface of the test rig operates intuitively via a PC
with a touch screen, whereas for the total control of the system a PLC
is used. In order to provide realistic control of the motors, different
electric bike motor controllers can be integrated into the system.
“ETU chose the WT1800 power analyser largely based on previous
experience, but also because it could be upgraded to six channels
and combined with a torque sensor to measure the mechanical
performance of the drive units. This way, we are ready to meet future
challenges”, says Jürgen Bläsi, Managing Director of ETU GmbH.
The laboratory power supply device simulates the battery and feeds
a current of up to 50 A into the motor controller. The output current of
the power supply is measured by the fourth channel of the WT1800.
The motor controller generates a corresponding 3-phase signal to
drive the motor. The actual power delivered to the motor is measured
using the current transformer and power analyser, and the mechanical power on the torque transducer is detected by the WT1800. In this
way, the efficiencies of both the individual powertrain components as
well as the overall efficiency of the system can be determined.
1.2kV, 80mΩ, All-Silicon Carbide Six-Pack and Associated
Six-Channel Gate Driver
Richardson RFPD, Inc. announced the
availability from stock and full design support
capabilities for a new 1.2kV, 80mΩ all-SiC
six-pack (three-phase) module and associated six-channel gate driver from Cree, Inc.
The CCS020M12CM2 includes C2M™
MOSFETs and Z-Rec™ diodes and features
ultra-low loss, high-frequency operation, zero
reverse recovery current from the diodes,
zero turn-off tail current from the MOSFETs,
fail-safe operation, ease of paralleling, and
a copper baseplate and aluminum nitride
Bodo´s Power Systems®
February 2015
The module enables compact and lightweight
systems, offers high efficiency operation,
mitigates over-voltage protection, and
facilitates reduced thermal requirements and
system cost.
The CCS020M12CM2 is ideally suited for
a range of applications, including solar
inverters, three-phase power factor correction, regenerative drives, UPS and SMPS,
and motor drives. It is pin-compatible to the
industry-standard EconoPACKTM2 package
International Exhibition and Conference
for Power Electronics, Intelligent Motion,
Renewable Energy and Energy Management
Nuremberg, 19 – 21 May 2015
Power meets electronics –
Join the PCIM Europe!
Your market place for power electronics
More information at +49 711 61946-0
[email protected] or pcim-europe.com
40V 0.99mOhm MOSFET in a DFN5x6 Package
Alpha and Omega Semiconductor Limited, a designer, developer
and global supplier of a broad range of power semiconductors and
power ICs, announced the release of AON6590, the flagship device
in its new 40V medium voltage portfolio. The AON6590 is designed
to address a wide range of applications including primary-side and
secondary-side switching in telecom and industrial DC/DC converters, secondary-side synchronous rectification in DC/DC and AC/DC
converters, as well as POL modules for telecom systems.
The AON6590 is the lead product in what will be a new portfolio of
40V products that are optimized for switching power conversion.
Compared to previous generations, this new product improves onresistance by 30% which reduces conduction losses and allows lower
case temperatures during heavy load operation. AON6590 also offers
low output capacitance, reducing turn-off energy loss, thus enabling
higher efficiencies in hard-switched applications. In addition to the
performance benefits, this device has been designed with a robust
UIS capability to handle extreme conditions such as output short
circuits or start-up phases. The AON6590 is available in a compact
DFN5x6 power package.
“AON6590 marks a new generation of products designed to enable
rugged system solutions with higher power density. The new device
allows our customer to design power supplies that run cooler and
improve overall system reliability.” said Stephen Chang, Sr. Product
Marketing Director at AOS. AON6590 Technical Highlights
Buck Regulator added to Family of Automotive-Grade Regulator ICs
The A8590 buck regulator from Allegro MicroSystems Europe is the
latest addition to the company’s industry-leading family of automotivegrade AEC-Q100 qualified regulator ICs.
The device has been designed to provide the power-supply requirements of next-generation car audio and infotainment systems, and
provides all the control and protection circuitry for a 3 A regulator
which will withstand the rigours of a wide automotive battery input
voltage range. The A8590 can also be used in cluster and centre
stack applications and in advanced driving assistance systems.
The A8590 employs pulse frequency modulation to draw less than
50 μA from a 12 V input while supplying a 3.3 V/40 μA output. After
startup, the A8590 operates down to an input voltage (falling) of at
least 3.6 V, and maintains ±1% output voltage accuracy.
Other features of the A8590 include PWM/PFM mode control and the
ability to synchronise PWM frequency to an external clock. It also has
a “sleep” pin for an ultra-low current shutdown mode. The device has external compensation to accommodate a wide range
of frequencies and external components, and provides a power-on
reset signal validated by the output voltage.
Wireless Power Chips Used for State-of-the-Art ‘Cube’ Remote Control
Integrated Device Technology, Inc. announced that its wireless power chips are
enabling wireless charging in 4MOD Technology’s innovative new “Cube” remote
control. The French company chose IDT’s magnetic induction transmitter and
receiver solutions to develop its wireless charging system, compliant with the
Wireless Power Consortium (WPC) 1.1 Qi specification.
The Cube is a revolutionary remote that allows users to control all functions of
their entertainment center—TV, video, music and radio—with a few simple gestures. The sleek black box is charged wirelessly by placing it atop its base.
The Cube deploys the IDT P9038 single-chip WPC 1.1 5V wireless power transmitter in the base unit and the IDT P9025B single-chip ultra-compact wireless
power receiver in the remote control.
Bodo´s Power Systems®
February 2015
Power Factor Corrected Ac-Dc Drivers for LED Lighting
ON Semiconductor, driving energy efficient innovations, announces
two series of power factor corrected (PFC) offline Ac-Dc drivers for
high performance LED lighting applications. Extending the NCL3008x
family of products, the NCL30085, NCL30086 and NCL30088 address
single stage design implementations up to 60 watts (W) that require
high power factor. The NCL30030 broadens the existing solutions
which support higher power (up to 150 W) two stage topologies that
require low optical ripple and wide LED forward voltage variation.
The NCL30085, NCL30086 and NCL30088 utilise a power factor
corrected current control algorithm which makes them suitable for
flyback buck-boost, and SEPIC topologies. By operating in quasiresonant mode these devices are able to deliver optimum efficiency
across wide line and load levels. The innovative control methodology
they employ allows strict current regulation to be achieved (within 2
percent typically) solely from the primary side.
The non-dimmable NCL30088 is complemented by the NCL30086,
which is ‘smart-dimmable’, supporting analog and/or pulse-width
modulation (PWM) dimming with a single input that controls the
average LED current. Completing the series is the NCL30085 which
supports three levels of log step dimming (70 percent, 25 percent and
5 percent).
The NCL30030 is a two stage PFC controller plus quasi-resonant
flyback controller optimized for medium and high power LED lighting
applications up to 150 W. This device is best suited for commercial
lighting such as lowbay, highbay and streetlighting. The NCL30030
makes use of a proprietary multiplier architecture to achieve low harmonic distortion and near-unity power factor while operating in critical
conduction mode (CrM).
Magna-Power’s high frequency IGBT-based programmable DC power supply line spans 1.5 kW to 2000 kW+
with hundreds of models to target a variety of different applications.
Using a Magna-Power supply is as simple or sophisticated as the application demands with front panel control, 37-pin
isolated analog-digital I/O and a computer interface. Remote programming is supported through a variety of development
environments by a provided National Instruments LabVIEW™ driver, IVI driver and SCPI command set over RS232,
TCP/IP Ethernet, IEEE-488 GPIB and USB.
Designed and manufactured in the USA. Available worldwide.
SL Series
XR Series
TS Series
MS Series
MT Series
1.5 kW, 2.6 kW, 4 kW
2 kW, 4 kW, 6 kW, 8 kW, 10 kW
5 kW to 45 kW
30 kW, 45 kW, 60 kW, 75 kW
100 kW to 2,000 kW+
1U Rack-mount
2U Rack-mount
3U to 9U Rack-mount
Floor Standing
Floor Standing
No. of Models
Voltage Range
0-5 Vdc to 0-1,000 Vdc
0-5 Vdc to 0-10,000 Vdc
0-5 Vdc to 0-4,000 Vdc
0-5 Vdc to 0-4,000 Vdc
0-16 Vdc to 0-4,000 Vdc
Current Range
0-1.5 Adc to 0-250 Adc
0-0.2 Adc to 0-600 Adc
0-1.2 Adc to 0-2,700 Adc
0-7.2 Adc to 0-4,500 Adc
0-24 Adc to 0-24,000 Adc
Power Levels
February 2015
Bodo´s Power Systems®
SMT2015_KV_E_90x270 16.09.14 12:40 Seite 1
International Exhibition and Conference
for System Integration in Micro Electronics
Reference Design for
High-Power LED-Lighting
Power Integrations, the leader in high-efficiency, high-reliability LEDdriver ICs, announced a reference design for LED streetlights, highbay lights and other high-power LED-lighting applications. The new
design, RDR-382, describes a constant current, 43 V (nominal), 150
W reference power supply for 90-265 VAC solid-state lighting, utilizing
Power Integrations HiperPFS™-2 PFC controller ICs and HiperLCS™
integrated LLC power stage ICs.
Nuremberg, 5 – 7 May 2015
The place to be!
Traditional dual-stage drivers with separate PFC and LLC stages
produce a constant-voltage (CV) output requiring multiple DC-DC
converters to convert the output to constant current (CC). In contrast,
RDR-382 uses a novel feedback and control scheme which enables
the LLC to provide constant current directly at the output. As a result,
component count is cut by approximately one-third, efficiency is increased to > 93 %, and the elimination of the DC-DC converter stage
significantly reduces size. Additionally, the high nominal LLC switching
frequency (250 kHz) reduces the size of the required magnetics, while
the use of a continuous-conduction-mode, variable-frequency PFC
stage reduces EMI compared to fixed-frequency alternatives.
Comments Andrew Smith, senior product marketing manager for
Power Integrations: “Reliability is especially important for high-power
lighting applications above 75 W output. Because this design is high
efficiency, less heat is generated. In combination with a reduced
component count, this ensures a long lifetime.” Power Integrations
Launches New Reference Design for High-Power LED-Lighting Applications RDR-382 can be used to drive single or multiple LED strings
and allows analog dimming to be implemented with a 0-10 VDC input.
The reference design can be downloaded from:
Mesago Messe Frankfurt GmbH
Rotebuehlstr. 83 – 85
70178 Stuttgart, Germany
Tel. +49 711 61946-828
Fax +49 711 61946-93
[email protected]
125 °C Hybrid Polymer-Aluminum Electrolytic Capacitors
Cornell Dubilier Electronics, Inc. (CDE) announces the release of
type HZC Hybrid Polymer-Aluminum electrolytic capacitors. Rated for
125 °C, type HZC combines the advantages of aluminum electrolytic
and aluminum polymer technology. These hybrid capacitors have
the ultra-low ESR characteristics of conductive aluminum polymer
capacitors packaged in a V-chip, SMT case with high capacitance
and voltage ratings that were previously available only in aluminum
electrolytic technology. Applications for type 125 °C hybrid capacitors
include a variety of industrial power conversion, lighting control and
automotive applications.
Capacitance values for type HZC range from 10 to 330 µF at voltage ratings from 25 to 63 VDC and ripple current values exceeding
2000mA for some of the larger chip sizes. When operated at their
rated temperature of 125 °C and rated voltage at full ripple current rating, type HZC capacitors have a load life exceeding 4,000 hrs.
“The hybrid series gives the design engineer the best of both worlds”
says Bill Haddad, Product
Manager. “Hybrid capacitors utilize a combination of liquid electrolyte
and solid polymer giving them high ripple current capability at high capacitance and voltage ratings. They allow the design engineer to use
fewer capacitors to meet the capacitance and ripple current demands
for their power conversion application.” Haddad continued.
Universal PMIC Offers Up to 40V Input
Exar Corporation introduced the XR77129, a quad output programmable Universal PMIC with an input operating voltage range of 6V
to 40V. Its patented control architecture is well suited for 40V inputs
using a 17-bit wide PID voltage mode VIN feed forward architecture.
This controller offers a single input, quad output, step-down switching
regulator controller with integrated gate drivers and dual LDO outputs.
It can also monitor and dynamically control and configure the power
system through an I2C interface. Five configurable GPIOs allow for
fast system integration for fault reporting and status or for sequencing
The XR77129 is quickly configured to power nearly any FPGA, SOC
or DSP system through the use of Exar’s design tool, PowerArchitectTM and programmed through an I²C based SMBus compliant
serial interface. PowerArchitect 5.2 has been upgraded to support
the additional capabilities of the XR77129 including output voltage
ranges beyond the native 0.6V to 5.5V with the use of external feedback resistors. The XR77129 wide input voltage range, low quiescent
current of 450uA (standby) and 4mA (operating) make it an excellent
choice for a wide range of systems including 18V to 36VDC, 24VDC
or rectified AC systems used in the industrial automation and embedded applications.
Power Inductor family from
small and
filigree to
No “next generation” issues!
from stock
samples within 24 hrs
„„Design kits with free refills
„„Software tools for product selection
„„On-site Design-In consultations
„„IC reference designs
February 2015
embedded world Hall 2 Booth 420
Bodo´s Power Systems®
500 & 600W Quarter Brick Bus Converters with PMBus
Murata announced the DRQ series of single output digitally controlled
500 and 600 Watt DC-DC converters from Murata Power Solutions.
Incorporating a 32-bit ARM7 Processor, the 600W DRQ-12/50-L48
& 500W DRQ-12/42-D48 models are the second product families
offered by Murata Power Solutions to include a PMBusTM compatible
digital interface. The DRQ family is packaged in the industry standard
quarter-brick format incorporating the Advanced Bus Converter (ABC)
pinout for PMBus communications to an isolated DC-DC converter.
Both the DRQ-12/50-L48 (600 Watt) and the DRQ-12/42-D48 (500
Watt) units are packaged in an industry standard quarter-brick format
that will support the evolving Advanced Bus Converter (ABC) footprint
for isolated board mounted power modules. The –L48 module has a
12 VDC 50 Amp output, accommodates an input voltage range from
44 to 57 VDC and is ideal for Intermediate Bus Applications (IBA) with
a tightly controlled power source. The –D48 converter provides a 11.5
VDC 43.5 Amp output and supports the TNV 2:1 wide input voltage
range of 38 to 75 VDC. These highly efficient units, typically 95.5%,
run much cooler than less efficient units making them ideal for use in
modern space constrained telecoms and data networking equipment.
Typical applications include MicroTCA, servers, Storage, Networking
equipment, POE applications, wireless Networks along with industrial
applications and test equipment.
The PMBus interface facilitates power management features not previously available in an isolated power module rated at 500-600W in a
1/4tr brick format. By interfacing the DRQ module to the system’s I2C
bus a system engineer can monitor critical system level performance
requirements that include Vin, Iin, Vout, Iout and operating temperature. The PMBus can also be used to set warning flags for temperature, Vin, Vout, Iout and allows the user to customize parameters such
as Vout, Vin Turn on/off thresholds, output over voltage protection and
output current limit and ramp-up characteristics to name a few.
February 2015
Bodo´s Power Systems®
10 Watt Class Wireless Power Solution
Toshiba Electronics Europe (TEE) has
announced the launch of a wireless power
receiver IC, TC7765WBG, and a transmitter IC, TB6865AFG Enhanced Version, as
a 10-watt-class wireless power solution for
smartphones, tablets and mobile accessories using the Qi Standard Low Power
Specifications version 1.1, defined by the
Wireless Power Consortium (WPC).
With increasing awareness of the use of
wireless power supplies to charge portable
devices, such as smartphones, tablets and
their accessories, demand is growing for
higher-power wireless charging systems
that shorten charge times.
The receiver IC, TC7765WBG, increases
power by boosting the output voltage from
5V/1A to 7-12V/1A. The transmitter IC,
TB6865AFG Enhanced Version, realizes
a 10-watt- class wireless power solution
based on a revised peripheral circuit configuration and new software.
The TC7765WBG’s built-in protocol authentication logic circuit for power supply control eliminates the need
for set makers to develop software. The TB6865AFG Enhanced Version also supports the software necessary for the higher power supply
Important Author Dates
January 15th , 2015: Digest submitted via the website
May 1st, 2015: Notification of acceptance or rejection
July 1st, 2015: Final papers with IEEE copyright forms
Other Important Dates
February 16th, 2015 : Submission of Tutorial proposals
March 31, 2015: Submission of Special Session proposals
operation, allowing makers to easily incorporate 10-watt-class solutions into their products. This advance will reduce development times
for 10-watt-class wireless power supplies for manufacturers’ systems.
The Seventh Annual IEEE Energy Conversion Congress and
Exposition (ECCE 2015) will be held in Montreal, Canada, on
September 20 - 24, 2015. ECCE 2015 is the pivotal international conference and exposition event on electrical and electromechanical energy conversion. To be held for the first time outside
USA, ECCE 2015, in Montreal, Canada, will feature both industry-driven and application-oriented technical sessions, as well as
industry expositions and seminars. ECCE 2015 will bring together practicing engineers, researchers and other professionals for
interactive and multidisciplinary discussions on the latest
advances in various areas related to energy conversion.
Please visit http://2015.ecceconferences.org for more information or contact the ECCE 2015 Technical Program Chairs at
[email protected]
For exhibiting at ECCE 2015, please contact Exhibition Chair,
Steve Sprague at [email protected]
For more about Montreal and its surrounding areas, please visit
February 2015
Bodo´s Power Systems®
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400 W Ac-Dc Power Supplies Comes in Four Compact Chassis Mount Case Styles
CUI Inc announced a family of compact 400 W ac-dc power supplies
to its power portfolio. The PCM-400 series is housed in four optional
chassis mount case styles, including a compact U-frame measuring
6 x 4 x 1.5 inches (152.4 x 101.6 x 38.1 mm) and enclosed versions
with top or rear fan options. Featuring a wide range of available volt-
ages, multiple protections and peak power capabilities up to 700 W
within a 500 µs duty cycle, this series is ideally suited for numerous
ITE, telecommunications and industrial applications.
The PCM-400 power supplies meet EN60950-1 standards, carry UL/
cUL and TUV safety certifications, and provide EN55022 class B EMI
compliance. They feature 3000 Vac input-to-output isolation and an
output-to-ground isolation of 1500 Vac.
The series provides a universal 90~264 Vac input for global operation
and comes available in eight separate single output models ranging from 12 to 54 Vdc. Dual output versions are also available. The
power supplies are rated for operation at full load from 0° to 50°C
ambient, derating to 50% load at 70 °C. Additional features include
active PFC, remote on/off control and protections for over voltage,
over current, short circuit, and over temperature.
Reliable 48W & 60W Open Frame AC/DC Power Supplies
RECOM’s new RAC48/OF and RAC60/OF
Class II open frame power supplies offer
48W or 60W output power with excellent
performance, even at high ambient temperatures. With an operating temperature range
of -20°C to +50°C at 100% load and up to
70°C at derated load, there is typically no
need for active cooling.
These compact AC/DC modules are highly
efficient, have a long hold-up time (60ms)
and are also compliant with the European
ErP directive (<0.5W in standby). The PSUs
1 high quality components to
are also
built with
ensure a long, trouble-free life.
Both series are available with output voltages of 5VDC, 12VDC, 15VDC and 24VDC,
adjustable via the on-board preset. The
DC outputs are fully protected with OCP,
OVP and hiccup SCP. With their universal
input voltage range of 90V to 265VAC and
3kVAC/1 minute isolation, they are suitable
for worldwide use.
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February 2015
Bodo´s Power Systems®
The 1st Power Analyzer
... that lets you have it both ways.
Two paths.
One measurement.
In half the time.
Zero compromises.
The LMG670 with its unique DualPath architecture is the longawaited solution to a well known dilemma. When optimizing designs for power applications with high-frequency content, engineers
were forced to choose between analysis on the full power spectrum
or a specific portion only. Simultaneous measurements were impossible. To filter, or not to filter - that was the question.
Up to 7 channels · DC – 10 MHz · Accuracy 0.025 % · 500 µA to 32 A
DualPath is the answer.
3 mV to 1000 V · Touchscreen · Gbit-Ethernet · DVI / VGA interface
Experience the new LMG670 with DualPath live at:
ZES ZIMMER (Headquarter): +49 6171 628750 · [email protected]
Motor & Drive Systems 2015 January 21-22 (Orlando, FL, USA)
APEC 2015 March 15-19 (Charlotte, NC, USA)
EMV 2015 March 24-26 (Stuttgart, Germany)
ZES ZIMMER Inc. (US): +1 760 550 9371 · [email protected]
NexFET™ N-Channel Power MOSFETs Achieve
Industry’s Lowest Resistance
Texas Instruments introduced 11 N-channel power MOSFETs to its
NexFET™ product line, including the 25-V CSD16570Q5B and 30-V
CSD17570Q5B for hot swap and ORing applications with the industry’s lowest on-resistance (Rdson) in a QFN package. In addition,
TI’s new 12-V FemtoFET™ CSD13383F4 for low-voltage batterypowered applications achieves the lowest resistance at 84-percent
below competitive devices in a tiny 0.6 mm by 1 mm package. For
more information, samples or a reference design, visit www.ti.com/
The CSD16570Q5B and CSD17570Q5B NexFET MOSFETs deliver
higher power conversion efficiencies at higher currents, while ensuring safe operation in computer server and telecom applications. For
instance, the 25-V CSD16570Q5B supports a maximum of 0.59 milliohms of Rdson, while the 30-V CSD17570Q5B achieves a maximum
of 0.69 milliohms of Rdson. Read a blog, “Power MOSFET safe
operating area (SOA) curves for designing with hot-swap and ORing
FET controllers.” Download a 12-V, 60-A hot swap reference design
featuring TI’s CSD17570Q5B NexFET.
TI’s CSD17573Q5B and CSD17577Q5A can be paired with the
LM27403 for DC/DC controller applications to form a complete
synchronous buck converter solution. The CSD16570Q5B and
CSD17570Q5B NexFET power MOSFETs can be paired with a TI
hot swap controller such as the TPS24720. Download the application
note “Robust Hot Swap Designs” to understand how a transistor is
selected as a pass element and how to ensure safe operation under
all possible conditions.
Advertising Index
ABB Semiconductor
Bodos Power systems
Dr. Seibt
Bodo´s Power Systems®
Husum Wind
Magna Power
PCIM Europe
February 2015
Smart Systems Integration
Texas Instruments
Thermal Management
ZES Zimmer
Fast thyristor. When burning for induction heating
Melting systems, surface hardening or preheating – Induction heating applications
are manifold. ABB’s fast thyristors deliver the performance induction heating applications are asking for.
ABB’s family of fast switching thyristors are available with blocking voltages from
1,200 to 3,000 volt, average forward currents from 500 to 2,700 ampere and turn-off
times from 8 to 100 microseconds.
For more information please contact us or visit our website:
ABB Switzerland Ltd. / ABB s.r.o.
[email protected]
Tel.: +41 58 586 1419
StrongIRFET™ Rugged,
Reliable MOSFETs
PQFN 5x6
DirectFET Med.Can
D2-Pak 7pin
[email protected]
Vgs = 10V
• Ultra low RDS(on)
• DC Motors
• Inverters
RDS(on) max
@Vgs = 10V
Part Number
For more information call +49 (0) 6102 884 311
or visit us at www.irf.com
• High current capability
• Industrial qualified
• Broad portfolio offering
• Solar Inverter
• ORing or Hotswap
• Battery Packs