ST EVSPIN948 User manual

Introduction
The EVSPIN948 dual brushed DC motor driver expansion board is based on the STSPIN948.
It provides an affordable and easy-to-use solution for the implementation of brushed DC motor driving applications. Thanks to
the parallel operation, it can be easily converted to a single brushed DC motor driver with double current capability. In addition to
the internal current limiters, the integrated amplifiers allow it to be used in systems with external current control. The
EVSPIN948 is compatible with the Arduino UNO R3 connector and most STM32 Nucleo boards.
Figure 1. EVSPIN948 expansion board
Getting started with the EVSPIN948 dual brushed DC motor driver expansion
board based on the STSPIN948
UM3206
User manual
UM3206 - Rev 1 - July 2023
For further information contact your local STMicroelectronics sales office.
www.st.com

1 Safety precautions
Warning: Some of the components mounted on the board could reach hazardous temperatures
during operation.
While using the board, please follow the following precautions:
• Do not touch the components or the heatsink.
• Do not cover the board.
• Do not put the board in contact with flammable materials or with materials releasing smoke when heated.
• After operation, allow the board to cool down before touching it.
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Safety precautions
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2 Getting started
The main features of the EVSPIN948 expansion board are:
• Voltage range from 5 V to 58 V
• Phase current up to 5 A r.m.s for each motor
• Adjustable output slew rate
• Five different driving modes
• Two independent current limiters with adjustable OFF time
• Two integrated amplifiers with fixed gain
• Full protection set including: overcurrent, undervoltage lock out and thermal shutdown
• Compatibility with Arduino UNO R3 connector and STM32 Nucleo boards
The EVSPIN948 evaluation board is ready to be used in few steps. Follow this procedure to start your evaluation:
1. Check the setting of the jumpers based on your configuration as described in Section 3 Hardware
description and configuration
2. Connect the board with the STM32 Nucleo board through the Arduino UNO R3
3. Supply the board through the input 2 (VS) and 1 (ground) of the connector CN1
Further support material is available on the STSPIN948 product page www.st.com
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Getting started
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3 Hardware description and configuration
Figure 2. EVSPIN948 overview
The following tables provide the detailed pinout of the Arduino UNO R3 and ST Morpho connectors.
Table 1. Arduino UNO R3 connector table
Connector Pin(1) Signal Remarks
CN5
2 Offset enable (operational amplifier A)
3 Standby (active low)
4 Offset enable (operational amplifier B)
5 Enable bridge B
6 Operational amplifier A output
7 Ground
CN9
3 Voltage reference current limiter A
5 PWM1A input
6 PHA input
7 Enable bridge A
CN6
2 VDD
6 Ground
7 Ground
CN8
1 PHB input
2 PWM1B input
3 TOFFA signal Digital output in
PWM trimming mode
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Hardware description and configuration
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Connector Pin(1) Signal Remarks
CN8
4 Voltage reference current limiter B
5 TOFFB signal Digital output in
PWM trimming mode
6 Operational amplifier B output
1. All non-listed pins are not connected.
3.1 Driving mode selection
The EVSPIN948 can drive up to 2 DC motors at the same time.
The driving mode selection is done setting J5 and J6 jumpers (connected to MODE1 and MODE2 pins of the
device) on the top of the boards.
The table below briefly summarizes the possible configurations:
J5 J6 Driving mode Typical application
Max output
current (each
motor)
Output
RDS(ON)
Minimum
OCD
threshold
1-2 1-2 Reserved
1-2 2-3 Dual full bridge 2 x bidirectional brushed DC
(Figure 3)5 Arms 0.4 Ω 7 A
2-3 1-2 Dual half bridge
2 x high current unidirectional
brushed DC(1) (Figure 4)10 Arms
0.2 Ω
14 A
1 x high current bidirectional
brushed DC (Figure 5)0.4 Ω
2-3(2) 2-3(2) Dual full bridge with
mixed decay
2 x bidirectional brushed DC
or
Bipolar stepper
(Figure 3)
5 Arms 0.4 Ω 7 A
1. The motors can be connected between OUT and either VS (like in the figure) or GND. In the latter case, the current limiter
must be disabled. Motors can also be connected between OUT and LSS (without the need of disabling the current limiter),
soldering one of the motor cables directly to R12 or R13.
2. This configuration is only available with current limiter in Fixed OFF time mode (see Section 3.2)
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Driving mode selection
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Figure 3. Two bidirectional DC motors
B-
B+
A+
A-
M
M
VVS
GND
+
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Driving mode selection
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Figure 4. Two unidirectional DC motors – higher current
B+
B-
A-
A+
M
VVS
GND
M
+
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Driving mode selection
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Figure 5. One bidirectional DC motor - higher current
+
B+
B-
A-
A+
VVS
GND
M
3.2 Current limiter mode
The behavior of the current limiter can be changed by setting the J7 jumper (connected to MODE3 of the device)
as follows:
Table 2. Current limiter mode settings
J7 Current limiter mode J2 and J3 Decay time
1-2 Fixed OFF time Closed Depending on R6 and R7 resistors
(Figure 6)
2-3 PWM trimming Open Depending on PWM input signals
In Fixed OFF time mode, the current limiter A and current limiter B can be disabled by setting R6 and R7
to their minimum value respectively.
The current threshold can be set in two different ways:
• Trimming R41 and R46 resistors, leaving CN9.3 and CN8.4 floating
• Applying a square wave with variable duty cycle to CN9.3 and CN8.4, setting R41 and R46 to their
minimum value
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Current limiter mode
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Figure 6. tOFF versus ROFF
3.3 Output slew rate
The output slew rate can be increased moving the rotative switch SW1 clockwise. With the STSPIN948 device,
the slew rate value can be chosen from four different values, as shown in Table 3.
Table 3. Slew rate settings
SW1 RSR Slew rate (typ. at VS = 58 V)
C-1 closed 10 kΩ 0.3 V/ns
C-2 closed 5.6 kΩ 0.6 V/ns
C-3 closed 2.2 kΩ 1.2 V/ns
C-4 closed 1 kΩ 2 V/ns
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Output slew rate
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4 Thermal performance
An example of the thermal performances of the EVSPIN948 is provided in Figure 7 . The board is used in full-
bridge and parallel half-bridge configuration in a typical application to drive an inductive load with different output
currents ranging from 0.5 A to 3 A.
Set-up conditions:
•Planar orientation of the board and natural convection only
•Tambient = 25 °C
•PWM frequency = 20 KHz
•VS = 30 V
•Output slew rate setting = 2 V/ns
Figure 7. EVSPIN948 - thermal performances
0
20
40
60
80
100
120
140
0 1 2 3
Maximum
temperature [°C]
Output current
[ARMS]
Parallel half bridge
Full bridge
Figure 8. Thermal images (IOUT = 2ARMS)
Full-bridge configuration Parallel half-bridge configuration
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Thermal performance
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