Motion and power
ULN2003 stepper driver board
Switches the coil current of a small unipolar stepper.
What it does
The ULN2003 contains transistor drivers and clamp diodes. The controller sequences its inputs instead of powering coils directly.
Connections and compatibility
Connect IN1–IN4 to the four specified GPIO pins, the motor plug to its socket, and an external rated supply to the board. Join grounds.
Choosing one
Choose the board intended for your 28BYJ-48 plug. It is not a substitute for an A4988-style bipolar stepper driver.
Common mistakes
Input order in a software constructor can differ from physical IN1–IN4 order. Disconnect power before changing the motor connector.
Use it in a tutorial
- Stepper motors — Move a 5 V 28BYJ-48 with a ULN2003 driver, starting slowly and accounting for missed steps and backlash.