ULN2003A – STMicroelectronics

The STMicroelectronics ULN2003A is a high-voltage, high-current Darlington transistor array designed for interfacing logic-level signals to higher-power loads. This device comprises seven NPN Darlington pairs, each capable of sinking up to 500mA of current at the output, making it ideal for driving relays, solenoids, and stepper motors. The output voltage rating is 50V. Internal suppression diodes protect against inductive load kickback, simplifying circuit design and enhancing reliability. Typically supplied in a 16-pin DIP through-hole package, the ULN2003A offers easy breadboarding and prototyping capabilities. Its operating temperature range spans from –20°C to 85°C. The ULN2003A’s inherent gain simplifies interfacing low-current logic (TTL, CMOS) directly to higher-power actuators, minimizing the need for discrete components and reducing board space.