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Devantech MD03 20A H-Bridge Motor Driver


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The MD03 is a medium power motor driver, designed to supply power beyond that of any of the low power single chip H-Bridges that exist. Main features are ease of use and flexibility. The motor's power is controlled by Pulse Width Modulation (PWM) of the H-Bridge at a frequency of 7.8KHz.

The 15V MOSFET drive voltage is generated on board with a charge pump, so the module requires only two supply voltages;

  1. A standard 5V supply for the control logic, only 50mA maximum is required.
  2. Motor voltage, anything from 5VDC to 50VDC to suit your motors.
Control of the module can be any of:
  1. I²C bus, up to 8 MD03 modules, switch selectable addresses.
  2. 0V-2.5-5V analog input. 0V full reverse, 2.5V center stop, 5V full forward.
  3. 0V-5V analog input with separate direction control
  4. RC mode. Controlled directly from the RC receiver output.
  5. PWM. A simple onboard filter means you can use a 0%-100% 20KHz or greater instead of analog.

This item can be connected directly to a USB port on your computer using the optional USB to I2C Interface Module.

NOTE! The MD03 drives one motor. If you have two motors, you will need two MD03.

In Stock


Voltage: 5V for logic, 5V - 50V for motor
Current: 50 mA Max. for logic, up to 20A for motor
Control 1: 0V - 2.5V - 5V Analog for Reverse - Stop - Forward
Control 2: 0V - 5V (or PWM equiv.) with separate direction control
Control 3: RC Mode - Controlled by standard Radio Control system. Direct connection to RC receiver. (1mS - 2mS pulse with 1.5mS center off).
Control 4: I2C Interface, full control, acceleration and status reporting. Up to 8 modules on bus. SCL speed up to 1MHz
Current Limiter: Preset at 20A
Temperature Limiter: Reduces power gracefully if module overheats
Size: 4.45 x 2.05 x 1.18 in.
113 x 52 x 30 mm