MD04 - 20A H-Bridge

The MD04 is a medium power motor driver and is an upgraded replacement for the MD03, the main features are ease of use and flexibility. The motor's power is controlled by on-board Pulse Width Modulation (PWM) generators driving the H-Bridge Transistors.

Voltage - 5v - 24v 
Current - up to 20A 
Control 1 - 0v - 2.5v - 5v Analogue 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 
Control 5 - Serial at 5v levels and up to 115.2k baud rate
Current limiter - Preset at 20A 
Temperature limiter - Reduces power gracefully if module overheats 
Size - 113mm x 52mm x 30mm

Full MD04 Documentation 

Examples
I2C bus tutor - general I2C guide
Arduino - control using an I2C interface and display using the LCD05
ATMEGA32 - Simple communication example
PIC18F4410 - driving the motor and displaying variables on the LCD03
PIC24FJ16GA002 - reading the result and displaying on a LCD03/LCD05
Picaxe18x - I2C communication example