A4988 Stepper Motor Driver Module

A4988 Stepper Motor Driver Module

The A4988 drives bipolar stepper motors with up to 1/16 microstepping — enabling smooth, precise motion control for CNC machines, 3D printers, robotic arms, and camera sliders. Up to 2A per coil, with a simple STEP/DIR interface that works with any microcontroller.

Key Specifications

• Microstepping: Full, 1/2, 1/4, 1/8, 1/16
• Max current: 2A per coil
• Motor voltage: 8–35V
• Logic voltage: 3.3–5V
• Interface: STEP + DIR (2 pins only)
• Includes: Heatsink

Current Adjustment — Critical Step

Before connecting a stepper motor, set the current limit by adjusting the onboard potentiometer. Formula: Vref = Current limit × 8 × Rs (where Rs = 0.1Ω on most boards). Exceeding the motor's rated current will cause overheating. Attach the included heatsink before use.