M5Stack H-bridge Unit(STM32F030)

M5Stack DC Motor H-Bridge Unit for I2C Control

The m5stack dc motor H-Bridge Unit combines an STM32F030 controller with the RZ7899 bidirectional motor driver to add controlled forward, reverse, braking, and PWM speed adjustment to embedded projects. The host communicates through I2C, so motor-control commands can be integrated without dedicating multiple host GPIO pins to direction and PWM signals.

The default I2C address is 0x20 and can be changed through the onboard DIP switch. This is useful when a system needs more than one motor driver on the same bus or when 0x20 conflicts with another peripheral. Confirm the complete I2C address plan before assembly, especially in systems with displays, sensors, and multiple motion modules.

Drive Bidirectional DC Motors up to the Stated Limits

The external DC input supports up to 12V and the stated maximum allowable current is 3A. A built-in power-switching circuit supports 6–12V and 5V power domains for different motor and system arrangements. Select the motor and supply so startup current, stall current, wiring, connector rating, and thermal conditions remain within the actual system limits.

PWM Speed, Direction, and Braking

Firmware can command forward rotation, reverse rotation, braking, and PWM-based speed control through the I2C interface. This makes the unit suitable for mobile robots, small mechanisms, doors, feeders, conveyors, smart-home actuators, and test rigs that need reversible DC motor motion.

Integrated Protection for Safer Prototyping

Overcurrent, overvoltage, and overtemperature protection are integrated into the module design. These protections improve robustness, but they do not replace correct motor selection, fusing, power-supply sizing, cable sizing, mechanical limit handling, or emergency-stop design. Test stall and jam conditions under the intended load before field deployment.

Integration Workflow

Connect the motor and external supply to the specified terminal interface, connect Grove I2C to the M5Stack host, confirm the DIP-switch address, then start with low PWM duty cycles while verifying direction. Add application-level ramping when sudden acceleration would stress gears, wheels, or the power supply. For mechanisms with hard travel limits, add end-stop sensors and stop logic rather than relying only on timed motion.

Technical setup details are available in the M5Stack H-Bridge Unit documentation.