ST STEVAL-TTM001V1 User manual

Introduction
The STEVAL-TTM001V1 evaluation kit is designed to demonstrate the highly efficient ST automotive-grade 100 V STripFET F7
series Power MOSFETs and BLDC motor driver IC operating in typical automotive low voltage (car battery up to 48 V), high
current motor control applications.
The kit includes a board to sense and condition currents, and a driver board with a programmable L9907 FET driver with full
diagnostics to manage all 36 STH315N10F7 Power MOSFETs on a power board also included in the kit.
The driver board also includes an ST motor control connector to interface with any compatible ST motor control board (not
included in the kit), and various other connectors and jumpers for monitoring and protection, motor position feedback
information, and auxiliary power.
Figure 1. STEVAL-TTM001V1 evaluation kit
5 kW low voltage high current inverter for automotive motor control applications
UM2673
User manual
UM2673 - Rev 1 - January 2020
For further information contact your local STMicroelectronics sales office.
www.st.com

1Evaluation kit features
1.1 Electrical and functional characteristics
The kit features the following main characteristics:
•Power board with insulated metal substrate (IMS) hosting 36 STH315N10F7 power MOSFETS in the
H²PAK-6 (6x switch) package for automotive applications.
•L9907 automotive gate drivers to drive the power MOSFETs providing full diagnostic and programmable
parameters (cross conduction, dead time, gate current, etc.) via SPI.
• Maximum power 5 kW at 48 V.
• Isolated current sensing, bus voltage and temperature monitoring.
1.2 Target applications
The STEVAL-TTM001V1 kit is designed for applications involving motor drives for electric traction, such as:
•urban electric cars
• small city buses
• other 48V electric vehicles
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Evaluation kit features
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2Safety and operating instructions
2.1 General terms
All operations involving transportation, installation and use, as well as maintenance, has to be carried out by
skilled technical personnel (national accident prevention rules must be observed). For the purpose of these basic
safety instructions, "skilled technical personnel" are considered as suitably qualified people who are familiar with
the installation, use, and maintenance of power electronic systems.
2.2 Intended use of evaluation kit
This evaluation kit is designed for demonstration purposes only and shall not be used for any commercial
purpose. The technical data, as well as information concerning power supply conditions, must be taken from the
relevant documentation and strictly observed.
2.3 Evaluation kit setup
• The evaluation kit must be set up in accordance with the specifications and the targeted application.
•The board contains electro-statically sensitive components that are prone to damage through improper use.
Electrical components must not be mechanically damaged or destroyed.
•Avoid any contact with other electronic components.
• During the motor driving, converters must be protected against excessive strain. Do not bend or alter the
isolating distances any components during transportation or handling.
2.4 Electronic connections
Applicable national accident prevention rules must be followed when working on the main power supply with a
motor drive. The electrical installation must be completed in accordance with the appropriate requirements. A
system architecture which supplies power to the evaluation board must be equipped with additional control and
protective devices in accordance with the applicable safety requirements (e.g., compliance with technical
equipment and accident prevention rules).
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Safety and operating instructions
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3Evaluation kit overview
The STEVAL-TTM001V1 evaluation kit is designed to let you evaluate STH315N10F7 power MOSFETs, which
are driven by the automotive grade L9907 three phase gate driver able to provide full diagnostic and
programmable parameters via SPI. The system includes a bulk capacitor board and a current sensing board.
The STEVAL-TTM001V1 can be interfaced with any ST MCU evaluation board with embedded ST motor control
connector and ST FOC firmware library support.
This kit has been tested with the STEVAL-TTM002V1 (not included in this kit) which features an SPC560P50L3
32-bit power architecture MCU for automotive applications.
Figure 2. STEVAL-TTM001V1 block diagram
DRIVING STAGEPOWER STAGE
SPI
Motor Control
ICS
Vin
5V DC/DC
3V3 DC/DC
DRV > PW
L9907
driver
ENC/HALL
PW->DRV PW->DRV PW>DRV
12x
STH315N10F7
in H2PAK-6
-
Phase_U Phase_V Phase_W
Shunt
resistor
Shunt
resistor
Shunt
resistor
12x
STH315N10F7
in H2PAK-6
12x
STH315N10F7
in H2PAK-6
connector on top
connector on bottom
NTC
LEGEND
12V DC/DC
DRV > PW DRV > PW
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Evaluation kit overview
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4STEVAL-CTM004V1 power board
The STEVAL-CTM004V1 power board of the evaluation kit has 36 STH31*N10F7 N-channel Power MOSFETS in
the H²PAK-6 package. A gate resistor is placed near each power MOSFET to eliminate parasitic oscillation. A
pull-down resistor between the gate and the source of each transistor helps to avoid capacitive coupling driving
the transistor and unwanted switch-on when gate is floating. A snubber RC circuit on each switch limits the rate of
voltage change during switching transitions to reduce electromagnetic interference (EMI) and losses.
two decoupling capacitors close to the switching power MOSFETs reduce ringing on the VDS and voltage stress
on the devices. The capacitors reduce voltage overshoot caused by abrupt current change in the parasitic
inductors in the circuit.
To monitor the temperature of the power board and provide over-temperature protection, three NTCs are placed
on the power board near the drain of one power MOSFET for each inverter leg.
The power section also has connectors for the driver board, with CON5 (phase_U), CON6 (phase_V) and CON7
(phase_W) for gate driving and NTC sensing, and J3 for bus voltage. The board also hosts six towers near the
bulk capacitor board connection and three towers near the motor connection.
Figure 3. Main blocks of the STEVAL-CTM004V1 power board
4.1 STH315N10F7 N-channel Power MOSFET characteristics
The N-channel Power MOSFETs use STripFET™ F7 technology with an enhanced trench gate structure for very
low on-state resistance and reduces internal capacitance and gate charge for faster and more efficient switching.
The STH315N10F7 N-channel Power MOSFET has the following features:
• Designed for automotive applications and AEC-Q101 qualified
•Among the lowest RDS(on) on the market
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STEVAL-CTM004V1 power board
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• Excellent figure of merit (FoM)
•Low Crss/Ciss ratio for EMI immunity
•High avalanche ruggedness
Figure 4. Package and internal schematic diagram
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STH315N10F7 N-channel Power MOSFET characteristics
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5STEVAL-CTM007V1 driver board
Figure 5. STEVAL-CTM007V1 driver board functional blocks
1. connections to power board
2. motor control connector
3. ENC/HALL connector
4. ICS connector compatible with STEVAL-CTM008V1
5. L9907 driver
6. 3V3 DC/DC regulation
7. 5V DC/DC regulation
8. 12V DC/DC regulation
11 1
5
4
37
86
2
5.1 Power supply section
The power supply section provides all the voltages necessary for the circuitry. The required input voltage is 8 to
25 V input, which is supplied through connector JP1.
The input voltage is then converted to the following voltage levels:
• +12V for gate driver section (via an A7986 which is a 3 A step-down switching regulator)
• +5V and +3.3V for the control board (via an A6902 which is a 1 A switch step-down regulator)
5.2 Bus voltage monitoring
Bus voltage monitoring is implemented across an input voltage range of 5 to 75 V.
The following table shows the measured input voltage and the corresponding voltage level sent to the ADC input
of the SPC5 microcontroller unit.
Table 1. Input voltage bus and input signal to SPC5 ADC channel
Input Voltage ADC input
48V 2.0V
75V (max value) 3.1V
5.3 Temperature monitor
Three NTCs are placed on the power section to provide temperature information, although only one NTC may be
chosen at a time. Close one of the three jumpers S1, S2 or S3 to read the temperature near the U, V or W phase,
respectively. The microcontroller monitors processed signals to determine the temperature of the driver board and
manage any overload or over-temperature conditions.
To protect the hardware from excess temperature, a safe threshold is set in SPC5-MCTK-LIB.
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STEVAL-CTM007V1 driver board
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Table 2. NTC electrical characteristics
Symbol Parameter Test Condition Min Typ Max Unit
R-40 Resistance T = -40°C - 105.7 - kΩ
R25 Resistance T = 25°C - 4.7 - kΩ
R100 Resistance T = 100°C - 0.426 - kΩ
B B- constant T = 25°C to 50°C - 3500 - -
T Operating temp range - -40 - 125 °C
5.4 L9907 gate driver characteristics
The main features of the L9907 gate driver are listed below:
•dV/dt immunity ±50 V/ns in full temperature range
• AEC-Q100 qualified
•Supply voltage from 6 V to 54 V for working battery applications
• The device can withstand -7 V to 90 V at the FET high-side Driver pins
• Low standby current consumption
• 3.3 V internal regulator supplied by VCC pin
• Boost regulator for full RDSON down to 6 V and over voltage protection
• 3 low-side plus 3 high-side drivers
• PWM operation up to 20 kHz
• Gate driver current adjustable via SPI in 4 steps.
– Range set via external resistor.
– Maximum gate controlled current 600 mA
• Source connection to each MOSFET
• Input pin for each gate driver
RELATED LINKS
For detailed information and pin-out details regarding the L9907 gate driver, see the device datasheet
5.5 L9907 supply voltage configuration for 48 V applications
The L9907 automotive 3 phase BLDC driver has a default typical overvoltage threshold of 36 V. if 48 V is applied
to the VB pin, an OV error is triggered in the start phase with (B11) = ‘1’ in the DIAG register and the FS_FLAG
pin set to low.
As the VB pin is supplied from 48 V, the overvoltage protection VBov (B9) has to be disabled setting ‘0’ in CMD1
register. The overvoltage protection set on the boost regulator BST_C pin also needs to be disabled (default is set
to '0') by setting bit DIS_BSTov (B12) in CMD3 register to ’1’.
Note: This bit is only acknowledged if AND (EN1, EN2) = '0'. Trying to write it without lowering AND (EN1, EN2) will not
generate an SPI error, but the command will be ignored for the specific bit.
While setting CMD3 B12 to 1 disables the overvoltage protection on the BST_C pin, this solution does not allow
use of the FS_FLAG pin (which would always be low) to trigger an error in the microcontroller. This is due to the
fact that only the fault effect is disabled when VBov (B9) is set to ‘0’, while the fault is still latched in the SPI
register DIAG. Continuous polling must therefore be performed to query the device to verify whether errors are
present.
RELATED LINKS
See application note AN5124 for more details
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L9907 gate driver characteristics
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6Bus link capacitor board and current sensing board
6.1 STEVAL-CTM005V1 bus link capacitor board
In EV inverter systems, bus link capacitors reduce ripple current and suppress voltage spikes caused by leakage
inductance and switching operations. These capacitors provide a low impedance path for the ripple currents
caused by output inductance load, the bus voltage and PWM frequency.
The bus link capacitors must sustain a ripple current given by the following formula:
ΔI0.5t= 0.25 × Vbus
f×L
Where:
• ΔI0.5t is the maximum ripple current when duty cycle is 50%
•Vbus is the bus voltage
• f is the switching frequency
• L is the load inductance.
For a very low inductance motor (worst case scenario), ΔI0.5t is about 48 ARMS (Vbus = 52 V, f = 8 kHz and
L = 12 μH). If we add 10% to ΔI0.5t and choose electrolytic capacitors with a ripple current of 2.4 A, 22 electrolytic
capacitors are required. The resulting capacitance is about 6 mF, leading to a negligible ripple voltage on the bus.
Figure 6. STEVAL-CTM005V1 bus link capacitor board
6.2 STEVAL-CTM008V1 current sensing board
The STEVAL-CTM008V1 current sensing board is a general purpose board for motor control that can read up to
three phase motor currents and DC bus currents if four ICS are on-board. The board included in the kit hosts two
ICS to read two phase currents.
This sensing feature determines motor currents for digital control based on FOC algorithms. The sensors provide
high accuracy, with 4 mV/A over a temperature range of -40 °C to +105 °C and a nominal current of 200 ARMS.
The internal reference voltage of the ICSs (according to their VCC) is generally used, but the reference voltage
can be overdriven by providing an external reference voltage through the J1 connector. A female to female flat
cable is used to connect CON2 on the driver board with J1 on the current sensing board.
The signals from the sensors center around 1.65 V (average value at zero current).
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Bus link capacitor board and current sensing board
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Figure 7. STEVAL-CTM008V1 current sensing board
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STEVAL-CTM008V1 current sensing board
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