The 28BYJ-48 is a small and inexpensive 5V stepper motor commonly used in automation, robotics, and DIY electronics projects. It is designed to work seamlessly with the ULN2003 driver board, which allows easy control through an Arduino or other microcontrollers.

Key Features:

Motor Type: Unipolar Stepper Motor

Operating Voltage: 5V DC

Rated Current: ~240 mA

Step Angle: 5.625°/64 (gear reduction ratio 1:64)

Torque: Approximately 34.3 mN·m

Speed: Controlled via input pulses (RPM depends on pulse rate)

Number of Phases: 4

Gear Reduction Ratio: 1/64 – provides high torque and precision

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ULN2003 Driver Board Features:

Driver IC: ULN2003 (Darlington transistor array)

Input Voltage: 5V–12V

Interface Pins: IN1, IN2, IN3, IN4 (connect to Arduino digital pins)

LED Indicators: Show step sequence activity for easy debugging

Connector: 5-pin socket for 28BYJ-48 motor

Onboard Power Supply Jumper: Choose between external or internal power source

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Working Principle:

The ULN2003 driver receives digital control signals from the Arduino and powers the motor coils in sequence to rotate the motor shaft step-by-step.
By controlling the timing and sequence of these signals, you can achieve:

Clockwise (CW) or Counterclockwise (CCW) rotation

Precise position control

Variable speed movement

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Applications:

Robotics and automation projects

Camera sliders and pan-tilt systems

3D printers and CNC machines

Smart curtain or door openers

Educational electronics experiments

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Arduino Example Pins Connection:

ULN2003 Board Arduino

IN1 D8
IN2 D9
IN3 D10
IN4 D11
VCC 5V
GND GND