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Welcome back!
Next session will show you our latest solutions in
Power Management
Innovations in:
Low Voltage Motor Driver
Battery Supplied Applications
Milos Hofman
Technical Marketing EMEA
Agenda
• Innovations in Low Voltage Motor Driver
• Market position
• Key applications
• Product families overview
• Motion control engine
• Voltage Mode control
• Automatic current recirculation control
• Non-dissipative current sensing
• Innovations in Battery supplied applications
• Introduction to gas gauge
• How to estimate battery State-of-Charge
• Strengths of the gas gauge monitoring circuit - STC3115
• Positioning in ST portfolio and vs. competition
• Key advantages
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Low Voltage Motor Driver
PAST & NOW: Our Leadership
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Pioneer in BCD technology, sold today in Millions pcs
in many different application segments, including Industrial and automotive
Skills in mixing of power, analog and digital structures in a single IC
Strong expertise in systems and application requirements
Strong skills on “design for robustness” thanks to the continuous
improvement over 20 years of experience in the field
Mpcs
powerSPINTM
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ST Industrial Motor Control – the brand
Continuous New Products Introduction: 3 New products in the Y2012
• Advanced Micro-Stepping & Multi-Motor Drivers (new
easySPIN dSPIN, FlexSPIN) Accurate and smooth motion with
excellent position resolution; advanced multi-motor driving
• Monolithic Motor Drivers (Power Spin QFN)
Aggressive price, Compact, simple to use platform including a wide
range of devices to fit different design architecture
What’s more than competition
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Wide Portfolio (More than 60 PN) & Well recognized Brand
Innovative Patented techniques
Strong Application support (CTM support, design-in, trainings)
Excellent Evaluation Tools:
• More than 40 Evaluation Boards & demos
• Software for Design and Simulation and easy evaluation (GUI)
• Over 30 Application Notes
• Design Guides, Data Briefs, Articles, e-Presentations …
Have you seen the difference?
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Key applications addressed
Industrial
Medical
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• Diagnostic Equipment
• Breath support equipment
• Pumps
Stage lighting
Textile industry (sewing, knitting)
PCB assembly / analysis
Robotics, NC machines
Point Of Sale
Gaming
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• Casino machine
• Gambling machines
• Coin / banknotes management
Ticket machines
Bill counters
ATM systems
Vending machines
d
dSPIN
Intelligent buildings
Press equipment
• Security systems
• Camera positioning / focusing
• Antenna / satellite positioning
• Industrial Printers
• Paper folding, cutting machines
• Shredders
Wherever Stepper, DC & BLDC motors are used!
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xSPIN product family overview
Advanced
controller
Fully integrated drivers with embedded power stages
d
c
L6460
New
L6474
L6474
L62xx, L62xxQ
Microstepping
driver
DC and
Microstepping
driver
DC, BLDC and
stepper motor
driver
Adaptive decay
4 configurable full
bridge drivers
Full set of
protections
SPI-programmable,
diagnostics
DC-DC, GPIO, OPAmp, DAC, ADC
cSPIN
New
dSPIN
New
L6470 /
8
L6480/82
L6472
Digital core
for
motion control
Digital core
for
motion control
Microstepping
driver
Microstepping
controller for 8x
external MOSFETs,
85V
SPI-programmable,
diagnostics
SPI-programmable,
diagnostics
Performance and integration
New micro-stepping drivers
c
d
cSPIN
dSPIN
dSPIN & cSPIN: Motion Control engine
SPI
Power
µC sends dSPIN high level commands
• Free-run  run at constant speed
• Positioning  reach the desired position
…and dSPIN generates the movement
autonomously!
Not available at any competition IC!
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Example : Pick and Place machine
Task of the machine: Move a component from its initial position to the final one
Δ
Y
Δ
X
To do the job with conventional motor drivers require a
lot of interactions with the control unit, calculations and
processing performance
Using a dSPIN/cSPIN with motion control engine
simplifies the effort rapidly.
 Only one command (per driver) is needed
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Motion Control engine:
system architecture advantages
Without dSPIN (or cSPIN)
• Speed and position profiles
required complex MCU
routines
With dSPIN (or cSPIN)
• dSPIN (or cSPIN) does the tricky
part, following simple high-level
SPI commands
Fully digital motion management with simple commands
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Current vs. Voltage control modes
Current control mode
• System tries to impose phase current
applying a switching voltage
• It is a closed-loop approach
Current control (conventional)
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Easy to control
Robust against motor resonances
Higher vibrations
Higher noise
Needs precise current sensing
Voltage control mode
• System applies a sinusoidal voltage
to motor and phase
• It is an open-loop approach
Voltage control
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Need to compensate drifts
More sensitive to resonances
More Smooth operation
Less vibrations  more silent
Extremely high resolution possible
ST advanced implementation benefits from principal
advantages, minimizing the negative points
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L6470 & L6480: Voltage Control mode
• “Voltage Mode” brings Outstanding Performance, such as:
• Reduced resonances, mechanical noise and vibrations at low speed
• Reduced torque & speed ripple at low speeds
• Sine-Wave profile is achieved much more accurately than in current mode
• 128 µsteps beats 16 µsteps of competition
• Higher position resolution  more precise
• Smoother operation
• Fully compensated solution against
• Voltage generated by a motor (BEMF)
• Supply Voltage fluctuation thanks
to the integrated ADC
• Motor phase winding resistance
fluctuations with temperature
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BEMF compensation
Current (torque) decreasing
Current (torque) constant!
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What does the “decay” mean?
On Time
 Current rises
VS
Slow decay
 Current declines slowly
VS
Fast decay
 Current declines fast
IPH
IPH
IPH
M
M
M
RSHUNT
RSHUNT
VS
IPH
RSHUNT
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What does the “decay” mean?
(also called recirculation)
It is a way how to decline a current flow in the motor winding
( As motor winding has an inductive character which tends to keep a current flow )
Slow decay
 Slower current decline
Fast decay
 Faster current decline
Current flows only in the power bridge
Current flows also through the power supply
Lower current ripple and therefore
smoother & silent drive
Higher regulation error (or fail) in case
of fast change is required
Lower regulation error in case that
fast change is required
Higher current ripple and therefore
more noisy drive
ST Implementation combines advantages of both methods!
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Advanced Current control
Features
c
d
cSPIN
dSPIN
Chip regulates average
current vs. the conventional
peak current control
Adaptive decay
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Torque ripple reduction
Less vibrations
Soft and silent Motion
Precise positioning
Predictive current control
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Best smoothness
Most accurate positioning
c
Chip automatically performs the best
decay during the motor driving
Slow, fast or combination of both
 mixed decay
ST Patented principles: No competition IC
implements comparable algorithms
d
cSPIN
dSPIN
Performance
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Advantage of embedded current sensing (1)
d
d SPIN
core
NON Dissipative Current Sensing
Less Components
Smaller Solution
Cost Effective
Better
System Efficiency
Lower
Power Dissipation
No external high
dissipative shunt resistors
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Advantage of embedded current sensing (2)
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Solution used by competition
Current control reference programmed by analog
signal level on pins
ST easySpin / dSPIN
Programmed in a register of the L6474 via SPI 
Simple, fast design, Flexible!
Address
[Hex]
Register name
Register function
h09
TVAL
Reference current
d
Reference current = Vref / (8 * Risense)
Need extra Resistors  space consuming,
higher assembly cost, logistic issues,
lower reliability,…
ST Advantages
• No need of external components
• Can be modified and optimized
according to a load to save power
Available Tools
Communication board (same for all):
STEVAL-PCC009V2
Evaluation
Boards
Graphical User
Interface for PC
Firmware
Libraries
(for STM32)
EVAL6470H / PD
EVAL6472H / PD
EVAL6474H / PD
EVAL6480H, EVAL6482H
Available for all the listed products
on st.com
Available on st.com product pages for:
dSPIN - L6470,
easySPIN – L6474
(in development for dSPIN – L6472)
L647xH
L647xPD
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...a step ahead competition,
unique differentiation
Motion control engine with programmable speed profile & positioning
Innovative predictive current control
Adaptive decay implementation
Fully compensated Voltage mode control with outstanding resolution
Fully embedded current sensing
SPI interface supporting multiple devices (daisy chaining)
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What is next ?
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Gas gauge monitoring circuit
STC3115
Introduction to Gas Gauge monitors
For systems with batteries, a challenge is to
precisely predict the remaining time before
recharge or battery change.
• State of charge can be estimated with MCU
accuracy is low and consumption higher
• A battery monitoring device :
• measures voltage, current and temperature
of the battery even when MCU is in standby.
Low Consumption (<100 µA)
• keeps track of the battery charge &
discharge with High accuracy (<1%)
Battery indicator
Poor battery indicator without dedicated
gas gauge support.
Battery data
Current
Battery State-of-Charge
Remaining Percentage
0.32 A
80 %
Voltage
3.71 V
Remaining Time
2:06
Temperature
27 °C
Reliable and accurate battery state-of-charge
measurement preserves battery life time!
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How to estimate State-of-Charge
1.
Voltage Mode: Integration of Battery voltage variations over time
Voltage Measurement + Model Curve
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
= State of Charge (%)
Batteries Model Curves
• No need for resistor
• Low power / Low accuracy
Voltage mode is best:
• for initial estimation
• during system standby
2.
OCV : Open Cell Voltage (V)
SOC : State of Charge (%)
Coulomb Counter: Current flowing into the battery is accumulated (calculation) over time.
Current measurement through resistor: High accuracy but higher consumption.
Coulomb Counter is best:
• for high accuracy estimation during system run
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4 strengths of STC3115
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Embedded adaptive algorithm:
dynamically adjusts the initial battery
model curve.
• Temperature compensation
• Aging compensation
Power
management
Micro
Controller
Main Reset ctrl
IRQ
Charger
RSTIO
Alarm
Control
I2C
Thermal
protection
STC3115
+
-
Battery
pack
2
3
New battery detect: to reset the battery
monitoring.
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Automatic mode selection:
Voltage Mode or Coulomb Counter
according to system status.
Charge inhibit during voltage
measurement for better accuracy.
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STC3115 in our portfolio
New
Accuracy
0.25%
STC3115
Adaptive gas gauge
25µA
0.25% accuracy
NRND
STC3105
0.5%
Basic gas gauge
No T°C sensor
No clock input
STC3100
Full Feature
gas gauge
STW4102
Dual path
linear charger
+ gas gauge
1%
25µA
50µA
(NRND = Not Recommended for New Designs)
100µA
Current
Consumption
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• Innovative features :
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Why to use STC3115?
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Adaptive Gas Gauge
Voltage mode + Coulomb counter
Running in parallel
Initial State-of-Charge @ power-up
Direct State-of-Charge reading by MCU
Charger inhibition during Voltage measure
0.25% max battery voltage accuracy
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Battery insertion detection
Under Voltage Lockout filtering
Aging & Temperature compensation
Highest
Robustness
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Adaptable to all types of batteries
Custom battery model in SW driver
Model self-adjustement in Application
Voltage mode only is also possible
Highest
Flexibility
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45 µA power saving operating mode
2 µA (max) in standby mode
Highest
Accuracy
& Stability
Lowest power
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STC3115 versus competition
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Architecture / Partitioning / Positioning
Basic Gas Gauge
DFN8 3 x 8 package
Coulomb counter
No temperature sense
Higher consumption
(NRND)
STC3105
Voltage
Reg
Coulomb
counter
Reg
µC
Driver
SOC
Algo
Param
Adaptive Gas Gauge
CSP 1.4 x 2.0 package
(DFN10 2 x 2.5 TBC)
Full feature, highest accuracy,
lowest consumpt. with Coulomb
Counter
MAXIM
Coulomb
counter
µC
Reg
Driver
Reg
Temp Comp
Aging
Max17040/43
Algo
Voltage
µC
Param
SOC
Driver
Temp Comp
bq27425
No resistor (Internal)
CSP 2.69x1.75 package
Higher Consumption
Not specified accuracy
Not self- adaptive
Integrates dedicated MCU
temperature
Temperature
Param
SOC
STC3115
option
CSP 0.9 x 1.7 package
Lower Consumption
No resistor (No Coulomb
Counter)
Not specified accuracy
No temperature sense
Not adaptive
Algo
Voltage
TI
Voltage
temperature
Coulomb
counter
µP
Firmware
Algo
Temperature
Param
SOC
Driver
µC
STC3115 Tools
• Datasheet
• Design Note : STC3115 Flip-Chip Package Footprint guidelines
• Design Note : STC3115 Application integration Schematic and Layout
• Customer support to develop optimized software drivers, taking into account :
• Microcontroller / processor platform
• Battery specification
• Evaluation Board STEVAL-ISB014V2
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Experience with us the smoothest and most precise
Solutions for Motor Control
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