A DC motor converts electrical energy to rotational motion. Speed is proportional to applied voltage; direction is set by reversing polarity via an H-bridge driver (L298N, L293D, or DRV8833). PWM controls effective voltage by rapidly switching the supply on and off.
| Operating voltage | 5 – 12V |
| No-load current | ~70 mA |
| Stall current | ~500 mA |
| Control | PWM + direction |
| Driver | L298N / L293D |
| Speed range | 0 – ~300 RPM |
Two control pins (IN1, IN2) set direction via the H-bridge. A PWM signal on the Enable pin controls duty cycle — a higher duty cycle increases average voltage and thus speed. The H-bridge prevents shoot-through by ensuring only one side of each bridge arm is on at a time.
No position feedback without encoder. Speed varies with load. Back-EMF spikes can damage the MCU — use flyback diodes. Stall current is high and can damage driver at low PWM.