Advantages: Suitable for interfacing between low-level logic circuitry and multiple peripheral power loads. Disadvantages: None.
The ULN2003, ULN2004, ULN2023 and ULN2024 series are high‑voltage, high‑current Darlington arrays designed for interfacing low‑level logic with loads such as relays, solenoids, stepping motors, LED displays and heaters. They are offered in 16‑pin DIP (suffix “A”) and 16‑lead SOIC (suffix “L”) packages, with input resistors optimized for 5 V TTL/CMOS or 6‑15 V CMOS/PMOS logic.
Key electrical specifications include a continuous output current of 500 mA per driver, output voltage ratings of 50 V (ULN2003/2004) or 95 V (ULN2023/2024), operating temperature from –20 °C to +85 °C, and typical power dissipation up to 25 W (DIP) or 15 W (SOIC).
| Output Voltage Rating | 95 V |
|---|---|
| Input Voltage Compatibility | 5 V TTL or CMOS (ULN2003/2023) / 6‑15 V CMOS or PMOS (ULN2004/2024) |
| Package Types | 16‑pin DIP (A) and 16‑lead SOIC (L) |
ULN2003 and ULN2004 devices can withstand at least 50 V off‑state, while ULN2023 and ULN2024 can withstand up to 95 V.
Typical loads include relays, solenoids, stepping motors, magnetic print hammers, multiplexed LED and incandescent displays, and heaters.