ULN2003 Stepper Motor Driver IC

The ULN2003 is a 16-pin IC. It has seven Darlington Pairs inside, where each can drive loads up to 50V and 500mA. For these seven Darlington Pairs we have seven Input and Output Pins. Adding to that we can a ground and Common pin. The ground pin, as usual is grounded and the usage of Common pin is optional. It might be surprising to note that this IC does not have any Vcc (power) pin; this is because the power required for the transistors to work will be drawn from the input pin itself.

Pin Configuration

• Pin 1-7 (Input 1 to Input 7) : Seven Input pins of Darlington pair, each pin is connected to the base of the transistor and can be triggered by using +5V
• Pin 8 (Ground) : Ground Reference Voltage 0V
• Pin 9 (COM) : Used as test pin or Voltage suppresser pin (optional to use)
• Pin 10-16 (Output 1 to Output 7) : Respective outputs of seven input pins. Each output pin will be connected to ground only when its respective input pin is high(+5V)

Applications

• Used to drive high current loads using Digital Circuits
• Can be used to drive Stepper motors
• High current LED’s can be driven
• Relay Driver module (can drive 7 relays)
• Logic Buffers in digital electronics
• Used as Touch sensor for Arduino