NPN Darlington Transistor Array ULN2003

The NPN Darlington Transistor Array ULN2003 is a driver IC with seven NPN Darlington pairs in one 16-pin package. Each channel lets a microcontroller pin switch a load of up to 500 mA at up to 50 V, and built-in clamp diodes protect the chip when it drives relays, solenoids and motor coils. It is best known as the driver for the 28BYJ-48 stepper motor in Arduino projects.

NPN Darlington Transistor Array ULN2003 Specifications

• Channels: 7 Darlington pairs, open-collector outputs that sink current to GND
• Output rating: up to 50 V, 500 mA per channel (600 mA peak)
• Inputs: 2.7 kΩ series base resistor on each input for direct 5 V TTL/CMOS drive
• Protection: integrated clamp diodes from each output to the COM pin
• Pinout: inputs on pins 1–7, GND pin 8, COM pin 9, outputs on pins 16–10
• Package: 16-pin DIP

NPN Darlington Transistor Array ULN2003 Applications

• Driving 28BYJ-48 and other unipolar stepper motors
• Switching 5 V and 12 V relays from Arduino or ESP32 pins
• Solenoids, small DC motors and lamps
• Driving several LEDs or LED segments at higher current
• Robotics and automation labs

What's in the Box

• 1 × ULN2003 Darlington transistor array IC

Tip: The outputs sink current, so connect each load between the positive supply and an output pin, and join pin 8 to the microcontroller ground. When driving relays or motors, connect COM (pin 9) to the load supply so the clamp diodes work, and avoid running all seven channels at full current at once, because the package will overheat.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.