Stepper Motor (28BYJ-48 + ULN2003)
Rotates in precise steps; driven through its ULN2003 board.
How it works
A stepper motor moves in fixed increments instead of spinning freely, so you can rotate it to exact positions. The popular 28BYJ-48 is a cheap 5V geared stepper that ships with a small ULN2003 driver board.
Wire the driver's four inputs (IN1–IN4) to the Arduino and power the motor side from 5V. The Arduino energizes the coils in sequence — the built-in Stepper library handles the pattern for you.
Pins
- IN1–IN4
- Coil control — to four digital pins.
- + (5V)
- Motor power — use an external 5V supply.
- − (GND)
- To GND (shared with the Arduino).
Ratings
- Voltage
- 5 V
- Steps/rev
- ~2048 (geared)
Tips
- Power the motor from a separate 5V supply — it can brown out the Arduino.
- With the Stepper library, the pin order is IN1, IN3, IN2, IN4.