28BYJ-48 Stepper Motor with ULN2003 Driver

Motor TypeUnipolar stepper motorConnection Type5 Wire Connection (to the motor controller)Voltage5 Volts DCFrequency100 HzStep modeHalf-step mode recommended (8 step control signal sequence)Step angleHalf-step mode: 8 step control signal sequence (recommended)5.625 degrees per step / 64 steps per one revolution of the internal motor shaft.Full Step mode: 4 step control signal sequence11.25 degrees per step / 32 steps per one revolution of the internal motor shaftGear ratioManufacturer specifies64:1. Some patient and diligent people on theArduino forumshave disassembled the gear train of these little motors and determined that the exact gear ratio is in fact63.68395:1. These means that in the recommended half-step mode we will have:64 steps per motor rotation x 63.684 gear ratio = 4076 steps per full revolution (approximately).Wiring to the ULN2003 controllerA (Blue), B (Pink), C (Yellow), D (Orange), E (Red, Mid-Point)Weight30gThe motor has 4 coils of wire that are powered in a sequence to make the magnetic motor shaft spin. When using the full-step method, 2 of the 4 coils are powered at each step. The default stepper library that comes pre-installed with the Arduino IDE uses this method. The 28BYJ-48 datasheet specifies that the preferred method for driving this stepper is using the half-step method, where we first power coil 1 only, then coil 1 and 2 together, then coil 2 only and so onWith 4 coils, this means 8 different signalsULN2003 Stepper Motor Driver Board uses ULN2003 DARLINGTON ARRAYS to drive a 4-phase 5-wire UNIPOLAR stepper motor.Arduino has a built-inStepper Librarywith information regarding UNIPOLAR and BIPOLAR Stepper Motors.Documents:DatasheetSchematicsHere is atutorialfor connecting the 28BYJ-48 Stepper Motor to theULN2003 Stepper Motor Driver Board.Good notes regarding Steppers.