EMC measurements
of components
Summary
1.
EMC problem examples
2.
EM disturbance sources
3.
EMC certification ?
4.
EMC measurement for electronic systems
5.
EMC measurement for integrated circuits
2
April 15
EMC problem examples
A typical electromagnetic environment…
3
April 15
EMC problem examples
Electromagnetic interference issues in medical devices

Medical device EMI problems reported
by FDA between 1979 and 1993
EMI types
Reported cases Devices
Conducted
interference
20 (1 death)
Cardiac monitor,
infusion device,
defibrilator…
Radiated
interference
55 (4 deaths)
Pacemaker,
ventilator, cardiac
monitor
LF magnetic
field
6 (1 death)
Respirator,
pacemaker
ESD
10
Respirator,
infusion pump

http://www.emcs.org/acstrial/newsletters
/fall04/63_67.pdf
405 suspected EMI problems reported by FDA between 1994 and 2005, with
6 deaths, 170 injuries and 167 malfunctions. 72 % of cases concern
implantable devices.
4
April 15
EMC problem examples
Electromagnetic interference issues in military systems
29th July 1967 : accident of the American aircraft
carrier USS Forrestal. The accidental launching of
a rocket blew gas tank and weapon stocks, killing
135 persons and causing damages which needed
7 month reparations. Investigations showed that a
radar induced on plane wiring a sufficient parasitic
voltage to trigger the launching of the rocket.
H.M.S. Sheffield catastrophe: “During the Falklands War, the
British Ship H.M.S Sheffield sank after being hit by an Exocet
missile. Despite the Sheffield having the most sophisticated
antimissile defense system available, the system created EMI to
radiocommunications to and among the contingent of Harrier jets
assigned to the ship. While the Harriers took off, the missile
defense was disengaged to allow communications with the jets
and provided a window of opportunity for the Exocet missile.”
5
April 15
EMC problem examples
Electromagnetic interference issues in automotive
Interference Technology –
October 2011
Mercedez-Benz case: “During the early years of ABS, Mercedez-Benz automobiles
equipped with ABS had severe braking problems along a certain stretch of the German
autobahn. The brakes were affected by a near-by-near radio transmitter as drivers applied
them on the curved section of highway. The near-term solution was to a erect a mesh
screen along the roadway to attenuate the EMI. This enabled the brakes to function
properly when drivers applied them…. Eventually, automobile ABS was qualified by EMI
testing prior to procurement.”
6
April 15
EMC problem examples
Electromagnetic interference issues in aviation
« Disturbances of flight instruments causing trajectory deviations
appear when one or several passengers switch on electronic
devices. » (Air et Cosmos, April 1993)
NASA publication 1374 (1986 – 1995)
FAA Aviation Safety Reporting System has reported 12 cases of interference in aircraft due to
personal electronic devices since 2002.
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April 15
EMC problem examples
Electromagnetic interference issues in space aircraft
Vacuum cleaner incident: “During a Spacelab mission in 1985, the crew
decided to use the middeck vacuum cleaner instead of the one in the lab.
Switching the middeck vacuum on caused the voltage to drop and the
Remote Acquisition Unit to shut off. In preflight EMI tests, the vacuum cleaner
had not been tested and should not have been used in the lab. This case
shows how careful and attentive one must when dealing with EMC.” [Nasa
Publication 1374]
8
April 15
EM disturbance sources
Various disturbance sources that can affect electronic system operation
Human activity
Natural sources
Intentional
emission
Non intentional
emission
Electrostatic discharge
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April 15
EM disturbance sources
Interferences from telecommunication systems
MF
0.3-3MHz
Liaison sous
marine
HF
3-30MHz
Radio FM
Radio OC
TV VHF
CB
Radionavigation
1M
10M
UHF
300-3000MHz
EHF
30-300GHz
SHF
3-30GHz
IEEE
802.11
ISM
RFID
Radio AM
100K
VHF
30-300MHz
GSM
TV UHF
GPS
ZigBee
DCS
Wimax
Liaison
satellite
UMTS
1G
100M
WiFi
Gigabit
Fréquence (Hz)
10G
100G
 Narrowband emission, modulated signals.
 Regulation and planification of radioelectric spectrum controlled by ITU-R at
international level, and by « Agence Nationale des Fréquences » (ANFR) at
French level.
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April 15
EM disturbance sources
Interferences from electronic systems
 Parasitic noise generated by the activity (switching) of any electrical or electronic
devices
 The noiise is usually impulse type  broadband noise.
 Example : Radiated emission from a 16 bit microcontroller
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April 15
EM disturbance sources
The EM environment according to ITU-R 372-8
 Ambient field levels defined from EM survey in 70’s.
 Recent surveys show a 20 – 40 dB increase in semi-enclosed environment.
 Example: Survey of the average level of electric field in Canada during the 90’s
in urban and suburban environment: between 1 and 20 V/m.
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April 15
EM disturbance sources
The EM environment
 Site Agence Nationale des Fréquences (www.anfr.fr) – outil Cartoradio.
Champ E
Distance antenne – point
de mesure = 60m
Etot = 4.35 V/m
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April 15
Summary
 EM disturbances can induce major failures in electronic systems.
 The parasitic emission and susceptibility to EM disturbances must
be tested to ensure electromagnetic compatibility of an electronic
systems within a nominal environment.
 But it is a tedious task because:
 Diversity in terms of electronic devices
 Numerous types of disturbances (LF, HF, pulsed, modulated),
numerous EM environment
 Various EM coupling possibilities (conducted, radiated, nearfield…)
How defining generic tests to guarantee EMC for
any electronic systems in any EM environment,
with an industrial realism ?
14
April 15
The EMC certification
EMC European Directive
 The European directive 89/336/EEC (1996) and then 2004/108/EC (2004)
requires that all « electrical apparatus » placed on the European market :
 Do not produce electromagnetic interferences able to disturb radio or
telecom equipments , and the normal operation of all equipments
 Have a sufficient immunity level to electromagnetic interferences to prevent
any degradation of the normal operation.
 All manufacturers of « electrical apparatus » must
certify that the directive is supposed respected by
delivering a declaration of conformity and placing a
CE mark on the product.
CE mark
 Using harmonized standards adapted to the product to verify the
supposition of conformity is recommended
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April 15
The EMC certification
R&TTE European Directive
 The European directive 99/5/EC (1999) Radio & Telecommunications Terminal
Equipment which is applied to all telecom and radio equipments emitting on the
band 9 KHz – 3000 GHz replace the EMC directive. .
 R&TTE requires that telecom and radio equipments placed on the European
market: :
 Comply to safety constraints given by the Low Voltage directive
(73/23/EEC) (e.g. the limit of EM exposure for persons) and the EMC
constraints given by the EMC directive 2004/108/EC.
 Radio equipments use spectral resources dedicated for terrestrial and
spatial communications without generating any interferences.
 R&TTE mark:
Warning signal for class
2 equipments (special
recommandations)
Required for all
equipments under the
R&TTE directive
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April 15
The EMC certification
EMC normative bodies: the importance of EMC standards !
International
European
International Electrotechnical
Commission(IEC)
TC77
European Commitee for
Electrotechnical
Standardization
European
Telecommunication
Standards Institute
(CENELEC)
(ETSI)
Comité International Spécial des
Perturbations
Radioélectriques(CISPR)
Harmonized standards
IEC 61000-X
EN 50XXX
EN 55XXX
EN 6XXXX
CISPR-XX
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April 15
EN 300XX
The EMC certification
Commercial harmonized standard (non exhaustive list !)
Basic standard
(general and
fundamental rules)
Generic standard
(for equipments in a
specific environment)
Product
standard
(for a specific product
family)
EN 61000-4-x
(IEC61000-4-x)
EMC – Testing and measurement techniques
EN 61000-6-3
(IEC61000-6-3)
Generic Emission Standard, for residential, commercial and
light industrial environment
EN 61000-6-1
(IEC61000-6-1)
Generic Immunity Standard, for residential, commercial and
industrial environment
EN 55022
(CISPR22)
Information technology equipment (ITE)
EN 55014
(CISPR14)
Household appliances, electric tools and similar apparatus
EN 55012
(CISPR12)
Vehicles, boats and internal combustion engines
EN 330220
(ETSI 330 220)
EN 330330
(ETSI 300330-1)
Electromagnetic compatibility and radio spectrum matters
(ERM); Short Range Devices (SRD); Radio equipment to be
used in the 25 MHz to 1 000 MHz frequency range with power
levels ranging up to 500 mW;
Electromagnetic compatibility and radio spectrum matters
(ERM); Short Range devices (SRD); Radio equipment to be
used in the frequency range 9 KHz to 25 MHz and inductive
loop systems in the frequency range 9 KHz to 30 MHz
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April 15
The EMC certification
Commercial harmonized standard (non exhaustive list !)
 Automotive, military, aerospace and railway industries have developed
their own EMC standards.
Applications
Standard references
Automotive
ISO 7637, ISO 11452, CISPR 25,
SAE J1113
Aerospace
DO-160, ED-14
Military
MIL-STD-461D, MIL-STD-462D, MILSTD-461E
Railway
EN 50121
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April 15
The EMC certification
Case study 1

You want to place on the European market a ventilator for domestic
installation. It is supplied by mains (220 V).

Which EMC standard(s) should you follow ? What tests should you
conduct for the EMC certification ?
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April 15
The EMC certification
Case study 1

Application of EN55014-1 and 2:
“Electromagnetic compatibility –
Requirements for household appliances,
electric tools and similar apparatus” –
Part 1 = Emission, Part 2 = Immunity :

Any domestic electric/electronic
equipments, toys, electric tool supplied
under 250 V (monophase) (motors, heat
elements, thermostats …)

Except light modules (EN55015), radio
receivers (EN55025), gaming machine
(EN55022).
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April 15
The EMC certification
Case study 2
 Suggested emission tests:
Conducted emission
150 KHz – 30 / 300 MHz
Harmonic and flicker
Radiated emission

30 MHz – 1 GHz
Suggested immunity tests:
ESD
EFT / burst
Conducted immunity
Radiated immunity
Surge
Voltage dips and
interruptions
4 KV contact / 8 KV air
5/50 ns, 1 KV, 5 KHz repetition
150 KHz – 230 MHz, 3 V rms
80 – 1000 MHz, 3 V/m, modulation
AM 1 KHz 80%
1 KV 1.2/50 µs pulse on power
40 % variations of the power
supply, repeated 5×
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April 15
The EMC certification
Case study 2

You want to place on the European market a radio emitter/receiver for
remote control application in residential environment. The radio emitter
use the ISM band around 434 MHz. Its maximum radiated power is
limited to 500 mW. The emitter/receiver is an handheld device.

Which EMC standard(s) should you follow ? What tests should you
conduct for the EMC certification ?
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April 15
The EMC certification
Case study 2

The harmonized standard EN 300220: “Electromagnetic compatibility
and radio spectrum matters (ERM); Short Range devices (SRD); Radio
equipment to be used in the 25 MHz to 1000 MHz frequency range with
power levels ranging up to 500 mW” is adapted to short range devices :

either with a Radio Frequency (RF) output connection and/or with an
integral antenna;

for alarms, identification, telecommand, telemetry, etc., applications;

with or without speech.

It covers fixed stations, mobile stations and portable stations, all types of
modulation.
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April 15
The EMC certification
Case study 2
 List of suggested tests:
Frequency error or drift
Does the carrier frequency remains stable?
Effective radiated power
The radiated power must not exceed a max. level (<
500 mW)
Transient power
Adjacent channel power
The power transmitted in adjacent band must be
limited.
Spurious emissions
Parasitic emissions from the emitter and receiver
between 9 KHz and ?? Must be limited.
Frequency stability under
low voltage conditions
Duty cycle
Blocking or desensitization

The switching of the transmitter produces interferences
in adjacent spectrum
The emission from the transmitter must remain stable
even in extreme low power conditions.
The manufacturer must indicate the duty cycle of the equipment
Capability of the receiver to receive a wanted signal in
presence of unwanted signal
Some ESD tests should be also done …
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April 15
The EMC certification
Case study 3

You are a semiconductor manufacturers and you want to sell your
integrated circuits in the European market. Your ICs are dedicated to
automotive applications.

Which EMC standard(s) should you follow ? What tests should you
conduct for the EMC certification ?
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April 15
The EMC certification
Case study 3

If your integrated circuits can not operate by themselves, you don’t
need EMC certification.

However, your customers will certainly push you to guarantee the low
emission and susceptibility of your devices, require measurements,
models, support….

Examples of standards providing EMC measurement for ICs:
•
IEC 61967: Integrated Circuits, Measurement of Electromagnetic
Emissions, 150 kHz to 1 GHz
•
IEC 62132: Integrated circuits - Measurement of electromagnetic immunity,
150 kHz to 1 GHz
•
ISO11452: Road vehicles - Electrical disturbances by narrowband
electromagnetic energy - Component test methods
•
ISO 7637 or IEC61000-4-2/4/5 for ESD, pulse, surge testing.
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April 15
EMC measurement for electronic systems
Why EMC standard measurement methods

Check EMC compliance of ICs, equipments and systems

Comparison of EMC performances between different products,
different technologies, designs, PCB routings

Improve interaction between customers and providers (same
protocols, same set-up)
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April 15
EMC measurement for electronic systems
Emission measurements – General measurement set-up
Control Acquisition
Radiated or
conducted coupling
Acquisition system
50Ω adapted
path
Equipment / Device
under test
Coupling device
 Coupling network
 Antennas
 EMI receiver
 Oscilloscope
 Wave guide
 Current clamp…
Emission requirements verified ?
29
 Spectrum
analyzer
April 15
EMC measurement for electronic systems
Emission measurements – Emission spectrum
Amplitude (dBµV)
Frequency (MHz)
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April 15
EMC measurement for electronic systems
Emblematic EMC equipment – Spectrum Analyzer (EMI receiver)
Frequency adjustment
: Start, stop , center
Y= power (dBm, dBµV)
RBW – frequency
resolution, noise
floor reduction
50 Ohm input
X= frequency
VBW – smooth
display
Emission measurement requires high sensitivity and resolution
Emission
measurement standards often recommend spectrum
analyzer adjustment
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April 15
Amplitude adjustment :
Level reference, dynamic.
EMC measurement for electronic systems
Emblematic EMC equipment – Spectrum Analyzer (EMI receiver)

Principle: based on super heterodyne receiver
IN
Input
signal
Output signal
OUT
IF filter
Mixer
f
Frf
Local oscillator
LO
Fif
Frf+Fl
f
o
Flo
f
OUT IF filter
A
RBW
No
Fif
cos rf t  cos lot 
1
1
cos rf  lo t  cos rf  lo t
2
2
ωif
Detected power:
P = ½.A²+No.RBW
f
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April 15
EMC measurement for electronic systems
Emblematic EMC equipment – Spectrum Analyzer (EMI receiver)
Building
blocks and adjustable elements:
Input Attenuation
signal Attenuator
DC blocking
RBW
Mixers
IF filter
Low
pass
filter
Gain
IF
Analog
filter
Local
oscillator
Frequency
sweep
Fstart / Fstop
Fcenter / Span
Point number
Detector
Gain
log
VBW
Video
filter
Display
Reference
oscillator
33
Envelope
detector
April 15
EMC measurement for electronic systems
Emblematic EMC equipment – Spectrum Analyzer (EMI receiver)
Example:
effect of RBW and VBW.
Measurement
of 100 MHz sinus.
Amplitude = 90 dBµV
Amplitude = 20 dBµV
Sweep time :
VBW = 30 KHz  100 ms
VBW = 1 KHz  980 ms
Sweep time :
RBW = 100 KHz  2.5 ms
RBW = 10 KHz  100 ms
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April 15
EMC measurement for electronic systems
Emblematic EMC equipment – Spectrum Analyzer (EMI receiver)
Example:
Influence of detector type (peak vs. quasi-peak vs. average).
Measurement
of radiated emission of a microcontroller.
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April 15
EMC measurement for electronic systems
Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz)
EN55022
(Siepel)
Absorbents
Wide band
(calibrated) antenna
Faraday cage (with
absorbents: semianechoic chamber)
Device under test
1m
1m
EMI receiver or
spectrum analyzer)
R = 3 ou 10 m
1m
Power supply,
DUT control
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April 15
EMC measurement for electronic systems
Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz)
If far field and free space conditions ensured:
Optional pre-amplifier
Low loss
50 Ω cable
E field
EMI receiver
Vemi
50 Ω
Bilog antenna
(or log-periodic,
biconical, dipole…)
Vemi dBµV   EdBµV / m  AF(dB / m)  GaindB  LossdB
AF = Antenna factor
(from calibration)
The E field varies in 1/r with the distance r (the radiated power in 1/r²)  possible
extrapolation of field intensity.
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April 15
EMC measurement for electronic systems
Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz)
Let’s consider a radio receiver (such as a mobile phone). We suppose that it operates at 900
MHz, its antenna has an antenna factor of 29 dB/m, and its receiving floor is -90 dBm. It is
placed at 1 m of a “noisy” electronic equipment with a CE Mark.
Could you have a risk of interferences ?
38
April 15
EMC measurement for electronic systems
Immunity measurements – General measurement set-up
Disturbance generation
50Ω adapted
path
 Harmonic signal
 Transients
 Burst
Failure detection
Injected level
Extraction
Radiated or
conducted coupling
Coupling device
 Coupling
network
Equipment / Device
under test
 Antennas
 Wave guide
 Clamp…
Immunity requirements verified ?
39
April 15
EMC measurement for electronic systems
Immunity measurements – General test procedure for harmonic
disturbance
Start
F = Fmin
P = Pmin
Increase P
Increase F
Without EMI
Wait dwell time
Detection mask
Failure or P
= Pmax ?
F = Fmax ?
Save F and P
With EMI
End
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April 15
Failure
EMC measurement for electronic systems
Radiated immunity in (semi-)Anechoic chamber (30 MHz – 1 GHz)
Typical max. RI level:
Commercial product: 3 – 10 V/m
Automotive (ISO-11452-2): 25 – 200 V/m
Military (MIL-STD461E): 20 – 200 V/m
Aeronautics (DO160-D): 8 – 800 V/m
(Siepel)
Field
monitoring
Absorbents
Signal synthesizer
Wide band
(calibrated) antenna
Device under test
1m
1m
Power amplifier
( > 100 W)
Faraday cage (with
absorbents: semianechoic chamber)
R = 3 ou 10 m
1m
Power supply,
DUT control
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April 15
EMC measurement for electronic systems
Immunity measurements – Bulk current injection (BCI)
Signal synthesizer
RF disturbance
Induced current
measurement
Power amplifier
Directional
coupler
Load
LISN
Failure ?
DUT
Bus, cable
Faraday cage

Induced RF
current
Injection
clamp
Measurement
clamp
Interface
Microcontroler
circuit
Usually, the max. current is between 50 mA and 300 mA.
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April 15
EMC measurement for electronic systems
Immunity measurements – Pulse, ESD, bursts, surge…
Pulse
waveforms and severity levels defined by standards such as
IEC61000-4-x or ISO7637
Ideal Fast transient / burst
(IEC61000-4-4) (level 2)
Ideal ESD waveform at 4 KV
(IEC61000-4-2) (level 2)
Ipeak = 15 A
Vpeak = 1 KV (on 50 Ω)
Td= 50 ns
Tr = 5 ns
I30 = 8 A
Repetition rate = 5 – 100 KHz
Vpeak = 1 KV (on 50 Ω)
I60 = 4 A
Tr = 0.8 ns
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April 15
EMC measurement for integrated circuits
Why testing EMC for ICs ?

Integrated circuits are often the main cause of disturbances in electronic
equipment.

In recent years, there has been a strong demand for simple, reliable and
standardized measurement methods focusing only on integrated circuits
that electronic system designers could use to:

Obtain quantitative measure of emission/immunity from ICs establishing a
uniform testing environment

Qualify the low emission and high immunity performance of circuit.

Optimize circuit placement, routing, filtering and decoupling components

Evaluate the impact of IC redesign, technology improvement or package
modification.
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April 15
EMC measurement for integrated circuits
Why testing EMC for ICs ?
 Based on pre existing standards, such as:


CISPR 25 – Radio disturbance characteristics for the protection of receivers used
on board vehicles, boats and on devices – Limits and methods of measurements

IEC 61000-4 – Electromagnetic Compatibility (EMC) – Part 4: Testing and
measurement techniques

ISO 11452 part 1 to 7, Road vehicles – Electrical disturbances by narrow band
radiated electromagnetic energy – Component test methods
Measurement methods for EMC of Ics proposed by IEC:

IEC 61967:Integrated circuits -Measurement of electromagnetic
emissions, 150 kHz to 1 GHz.

IEC 62132: Integrated circuits - Measurement of electromagnetic
immunity, 150 kHz to 1 GHz.

IEC 62215: Integrated circuits – Measurement of impulse immunity
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April 15
EMC measurement for integrated circuits
International standards for IC emission measurement methods
IEC 61967-2
(TEM : 1GHz)
IEC 61967-2
(GTEM 18 GHz)
IEC 61967-5
(WBFC, 1 GHz)
IEC 61967-8
(IC-Stripline, 3/6 GHz)
Radiated method
IEC 61967-3
(Near field scan, 1/5GHz)
TEM Cell improvemnt
IEC 61967-6
(Magnetic field probe,
1GHz)
IEC 61967-4
(1/150 ohm, 1 GHz)
Appareil de
Investigation method
mesureAppareil
50 de
Câble coaxial ohms
mesure 50Ω
Z0=50Ω
Conducted method
46
April 15
IEC 61967-7
(Mode stirred chamber,
1 GHz)
EMC measurement for integrated circuits
IC Conducted emission
VddCore
Integrated
circuit
Icore(t)
Digital Core
VE/S(t)
Iosc(t)
Oscillator
Vdd osc
I/O
Load
Driver
PCB line
Vdriver(t)

Two noise sources: internal activity (power supply noise) and I/O
switching (Simultaneous Switching Noise, I/O line excitation)

Characterization of transient current and voltage induced by ICs.
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April 15
Load
EMC measurement for integrated circuits
IC Conducted emission - IEC 61967-4 –1 ohm / 150 ohms method
Vdd
RF current
PCB

Conducted emission is produced
by RF current induced by IC
activity.

The current induced voltage
bounces along power distribution
network and radiated emission.
IC
Decoupling
« Local » ground
49 Ω
1Ω
Spectrum
analyzer
I RF
VA 
2
IRF
« Global » ground
The « 1 ohm » method aims at measuring the RF current
flowing from circuit Vss pin(s) to the ground reference.
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April 15
EMC measurement for integrated circuits
IC Conducted emission - IEC 61967-4 –1 ohm / 150 ohms method

I/O switching is a major contributor to conducted emission.

They induced voltage fluctuation along power supply and I/O
lines.
Vdd
RF
current
Decoupling
150 Ω matching
network
I/O buffer
120 Ω
External
VRF
load
PCB
RF current
6.8 nF
51 Ω
Spectrum
analyzer
VA
VA  0.17VRF
(above150 KHz)
The « 150 ohms » method aims at measuring the RF voltage
induced at one or several IC output.
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April 15
EMC measurement for integrated circuits
IC current extraction from 1 Ω probe measurement

dsPIC33F: measurement in time domain and frequency of the voltage
across the 1 Ω probe  proportional to the IC current.
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April 15
EMC measurement for integrated circuits
IC Radiated emission - IEC 61967-2 – TEM cell
IC under test
50 ohm
Spectrum analyzer
Test board
TEM cell
(SAE J1752/3)
Pre-ampli
20-30 dB
Emission spectrum
Relation between the voltage
measured by the spectrum
analyzer and the radiated
emission from the circuit
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April 15
EMC measurement for integrated circuits
TEM cell – EM field inside the waveguide
y
Tapered
Tapered
transition
Aperture
transition
for DUT
Port1
Port2
50 Ω
50 Ω
septum
z

Field repartition:
R.J. Spiegel, and al.,“A
Method for Calculating
Electric and Magnetic Fields
in TEM Cells at ELF”, IEEE
Trans. on EMC, Nov. 1987
y
W
E
T
H
O
Wsept
W = 15 cm, T = 9 cm, Wsept = 10 cm, V = 1 V, y = 8 cm
Quasi homogeneous
field
52
x
o
TEM propagation
mode up to 1 GHz
o
|E/H| = 377 Ω
EMC measurement for integrated circuits
TEM cell – Field coupling with a DUT

Example: coupling with a 50Ω microstrip line

Dimensions of the microstrip: W = 2.5 mm, L = 75 mm, h = 1.6 mm, epsr = 4.5
VNA
Port1

Port2
Near
end
Far
end
50 Ω
load
50 Ω
load
septum
Appearance of non
TEM propag. mode
The magnetic field coupling
depends of the orientation of
the line in the TEM cell.
+ 20 dB/dec.
53
EMC measurement for integrated circuits
International standards for IC susceptibility measurement methods
IEC 62132-3
(BCI, 1 GHz)
IEC 62132-4
(DPI : 1 GHz)
IEC 62132-2
(TEM - GTEM : 1 / 18GHz)
Conducted methods
IEC 62132-5
(WBFC, 1 GHz)
Radiated
methods
IEC 62132-6
(LIHA, 10GHz)
IEC 62132-9
(Near-field scan, 1/5 GHz)
Investigation method
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IEC 62132-8
(IC-Stripline, 3/6 GHz)
TEM cell improvement
IEC 62132-7
(Mode stirred chamber, 1
GHz)
EMC measurement for integrated circuits
Conducted immunity

Applying conducted disturbances directly to IC pin ?
Radiated
disturbances
Electronic equipment
Victim circuit
Cables
PCB
Induced conducted
disturbances
Equivalent Thevenin
generator of RF
disturbances
Zs
Vs
Cables, PCB lines
Zc, Td
55
55
ZL
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Input impedance
of victim circuit
EMC measurement for integrated circuits
Conducted immunity - IEC 62132-4 – Direct Power Injection (DPI)

Individual test of each sensitive IC pin.
Signal Synthesizer
Test on 1 pin
Decoupling
network
Pforw Prefl
Amplifier
Directional
coupler
Failure detection
> 400 Ω
DPI Capacitor
( 1 – 10 nF)
Chip under test
• Oscilloscope
• Acquisition card
Susceptibility
threshold
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EMC measurement for integrated circuits
Conducted immunity - IEC 62132-4 – Direct Power Injection (DPI)
Example : DPI test on the power supply of an RF device
35
Forward power limit
Forward power (dBm)
30
25
20
15
10
5
0
1

Simple, repeatable, low power measurement

IC prequalification test
10
100
Frequency (MHz)
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57
1000
EMC measurement for integrated circuits
Conducted immunity - IEC 62132-4 – Direct Power Injection (DPI)
Class
I/O type – protection level
Fwd Power
(dBm - RMS)
Voltage (V)
(across 50 Ω)
1
30 - 37
10 - 22
Low filtering, pin connected to long cable
harness (power circuit)
2
20 – 27
3–7
Short connections, low filtering (signal
conditioning, communication line driver)
3
10 - 17
1-2
No direct connection with the environment
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EMC measurement for integrated circuits
Case study – Starcore EMC testing


The Starcore is 16-bit micro-controller used in automotive industry:
•
16 bit MPU with 16 MHz external quartz, on-chip PLL providing internal 133 MHz
operating clock
•
128 Kb RAM, 3 general purpose ports (A, B, C, 8 bits), 4 analog inputs 12 bits,
CAN interface
Prepare an EMC test plan: conducted emission (1 /150 Ω) and susceptibility test (DPI)
SIGNAL
Description
VDD
Positive supply
VSS
Logic Ground
VDD_OSC
Oscillator supply
VSS_OSC
Oscillator ground
PA[0..7]
Data port A (programmable drive)
PB[0..7]
Data port B (programmable drive)
PC[0..7]
Data port C (programmable drive) external 66MHz data/address
ADC In[0..3]
4 analog inputs (12 bit resolution)
CAN Tx
CAN interface (high power, 1MHz)
CAN Rx
CAN interface (high power, 1MHz)
XTL_1, XTL_2
Quartz oscillator 16MHz
CAPA
PLL external capacitance
RESET
Reset microcontroller
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