STEVAL-PTOOL4A BLDC Control Evaluation Board

STMicroelectronics STEVAL-PTOOL4A compact systems are designed to control a brushless DC (BLDC) or a permanent-magnet synchronous motor (PMSM) in applications such as a handheld battery-powered tools. It works on standard inputs such as throttle to control the motor torque/speed and to deliver power up to 250 W. The board can be connected to a suitable 21 V, 250 W power tool motor. More peak power can be delivered with a heatsink or with an arrangement for circulating air to achieve better power dissipation.

This reference design is ideal for high-performance motor control to realize power tools such as drill machines, grinders, disc cutters, circular saws, leaf blowers, handheld mowers, and more. The small form factor and ample computing power make it suitable even for applications such as drones, wheelchairs, home appliances, e-bicycles, and robotic platforms. The STEVAL-PTOOL4A includes a high-performance STM32G473CE MCU featuring integrated peripherals especially optimized for motor control applications controlling a 3-phase full-bridge converter consisting of six high current MOSFETs through triple half-bridge gate driver STDRIVE101.

The MCU features multiple ADC peripherals thereby enabling simultaneous sampling of motor phase currents and back EMF voltages. The board can leverage the ST MCSDK library to provide options of six-step or high-performance FOC algorithms with configurability.

Features

• Input voltage from 12 V_DC to 28 V_DC (Nominally 21 V)
• Output RMS current up to 20 A
• The board comprises the following key devices:
  • STM32G473CET6: A high-performance Arm®-based Cortex®-M4 32-bit MCU+FPU in LQFP48 (7 mm x 7 mm) package. The MCU embeds trigonometric and arithmetic math accelerators (CORDIC+FMAC), timers for motor control PWM and dead time generation
  • STDRIVE101: triple half-bridge gate driver in VFQFPN (4 mm x 4 mm) with inbuilt regulator
  • STL220N6F7: six N-channel 60 V, 0.0012 Ω typ., 120 A, STripFET™ F7 power MOSFET in a PowerFLAT™ 5x6 package
  • L6981NDR: 38 V, 1.5 A synchronous step-down converter in a PowerSO-8 package
  • LDL112: 1.2 A low quiescent current LDO with reverse current protection in an SO8-batwing package
  • TSV912IQ2T: dual rail-to-rail input/output 8 MHz op amp
  • BAT54KFILM: 40 V, 300 mA small signal Schottky diodes (single)
  • BAT54SWFILM: 40 V, 300 mA small signal Schottky diodes (series)
  • 2STR2160: low-voltage fast-switching PNP power transistor
  • 2STR1160: low-voltage fast-switching NPN power transistor
  • 2STR21STPS0560Z: 60 V, 0.25 A power Schottky rectifier
  • ESDALC6V1-1U2: single line low capacitance Transil™ for ESD protection is a precision 500 mA regulator
• Hardware features enabling efficient motor control options
  • Independent ADCs for 3-phase current sensing through shunts
  • 3 ADC channels for back EMF sensing
  • Bus voltage sensing
  • Hardware overcurrent protection through gate drive
  • Option for temperature sensing
  • Option for digital Hall sensors or encoder inputs
  • Option for mounting heatsink
• Empowered with a feature-rich STM32 motor control ecosystem for PMSM or BLDC
  • Wide configurability via motor control library (MCSDK), associated GUI, and profiler
  • Sensorless three-shunt or single-shunt vector field-oriented control (FOC) algorithm (default)
  • Suitable for high-performance STM32 ZeST (zero speed full torque) algorithm, available on request
  • Option for sensorless or sensored six-step algorithm
  • Tuning of drive dynamics
  • Selection of operating parameters such as switching frequency
  • Other parameter values for nominal and fault conditions, for example, over the current threshold
  • Torque or speed mode operation
  • Fully protected with overcurrent protection, undervoltage lockout, and thermal protection
  • Configuration examples with ST board designer, the JSON files are also provided
• Wide options for connectivity and user control
  • Serial wire debug (SWD) port for debugging/programming
  • Communication interfaces for SPI, UART, CAN/I²C pins
  • Connector for buttons and trimmer along with one onboard pushbutton switch
• Fault, status LEDs, and interface for external LED for illumination
• Options for enhancement with daughter cards
  • Connector for mounting daughterboard, for example, MEMS sensor board or memory
  • Connector for increasing input voltage range by replacement of DC/DC converter
• Test land areas on the board for monitoring important signals or DAC outputs for debugging