Controlling DC Motors with TB6612FNG and Arduino

Controlling DC motors with an Arduino Uno requires an intermediate power stage because the microcontroller's digital pins cannot supply the high current needed by motors. The TB6612FNG motor driver module bridges this gap using an internal H-bridge architecture, which allows you to independently control both the direction and speed of two separate DC motors, such as compact TT motors. Directional control is achieved by sending digital HIGH or LOW signals from the Arduino to the driver's input pins, configuring the internal switches of the H-bridge to route current forward or backward through the motor windings. Speed control is handled using Pulse Width Modulation (PWM) signals sent to the driver's PWM pins, which rapidly pulse the power on and off to vary the effective voltage delivered to the motors. An external 5V power supply connected to the motor voltage (VM) pin provides the heavy current required by the motors, keeping electrical noise and heavy loads isolated from the Arduino Uno. To ensure these separate power sources can communicate properly, a common ground wire must connect the external power supply's ground to the Arduino's ground pin, establishing a shared reference voltage for all control signals.