Serial Controlled Motor Driver (SparkFun)

The SparkFun Serial Controlled Motor Driver (SCMD) is a DC motor driver that’s been designed to drive small DC motors with ease. The SCMD is designed to emulate a typical register-based device in operation. It can be commanded by UART, I²C or SPI communication, and it can drive a constant 1.2A load per motor (peak 1.5A) at 11V. Need more than two motors? Chain multiple SCMDs together and command them through the same serial interface. Need more current? Each board’s output can be bridged to allow double current.

This driver board was designed to be affordable, compact and have more features than previous versions of serial-controlled motor drivers. Its main advantage is the variability of drive levels, making fine control adjustments a possibility. The SCMD is a 3.3V logic device! If you need to interface to 5V, you’ll need to use a logic level converter — or modify the SCMDs from stock to operate at 5V and supply your own regulated 5V.

Features:

• 1.5A peak drive per channel, 1.2A steady state
• Operates from 3 to 11 volts with 12V absolute max
• 3.3V default VCC and logic
• Max VCC in of 5.5V
• 127 levels of DC drive strength.
• Controllable by I²C, SPI or TTL UART signals
• Direction inversion on a per motor basis
• Global Drive enable
• Expansion port utilizing I²C, allows 16 additional drivers
• Exposed TO-220 heat sink shape
• Several I²C addresses, default UART bauds available
• Bridgeable outputs
• Optional fail-safe and diagnostics available.
• Configurable expansion bus bit rate to 50, 100 or 400kHz.
• Configurable expansion bus update rate from 1ms to 255ms, or by command only

Documents:

• Schematic
• Eagle Files
• Hookup Guide
• Datasheet
• GitHub