STMicroelectronics ULN2804A Darlington Array 8 NPN, DIP18

The STMicroelectronics ULN2804A is a high-voltage, high-current Darlington transistor array supplied in an 18-pin Dual In-line Package (DIP). It integrates eight Darlington pairs with common emitters and built-in suppression diodes, making it an ideal interface between low-level logic and high-power loads such as relays, solenoids, stepper motors, and LED displays.

Each channel can handle a peak load current of 600mA and a continuous current of 500mA, with an output voltage rating of 50V in the off state. The inclusion of integral suppression diodes for inductive loads protects the device from voltage transients, enhancing reliability and simplifying circuit design. Inputs are pinned opposite the outputs to facilitate cleaner and more straightforward printed circuit board (PCB) layout.

For applications demanding higher current, the outputs can be paralleled to increase overall current capability. The array features a high DC current gain (hFE) of 1000 and includes input resistors compatible with 6V to 15V CMOS logic levels, allowing for direct interfacing with standard microcontrollers and logic families without the need for additional components.

With an operating ambient temperature range of -20°C to 85°C and a power dissipation rating of 2.25W, this robust component is suited for demanding environments. Its through-hole mounting provides a secure and reliable connection for prototyping and production applications across various sectors.