ULN2003 Darlington Transistor Array — DIP-16 High-Current Driver IC

The ULN2003 is a DIP-16 Darlington transistor array designed for reliable high-voltage, high-current switching. With seven open-collector BJT channels, integrated suppression (flyback) diodes, and broad logic compatibility, it’s ideal for driving relays, lamps, displays, and other inductive or resistive loads from popular microcontrollers such as Arduino and Raspberry Pi. This robust IC delivers dependable performance for both professional designs and hobbyist projects.

🧩 Key Features

• High-voltage, high-current Darlington transistor array
• Seven independent Darlington drivers (7-channel)
• 500 mA output current per channel (600 mA peak)
• Up to 50 V output capability
• Integrated suppression diodes for inductive loads (COM pin for clamp connection)
• Inputs compatible with a variety of logic families (typical TTL/CMOS)
• DIP-16 through-hole package for easy prototyping and integration

📐 Technical Specifications

• Package Type: DIP-16
• Transistor Type: BJT — Bipolar Junction Transistor (Darlington array)
• Operating Temperature: −20°C to +85°C
• Storage Temperature: −55°C to +150°C
• Power Dissipation: 1 W (package total)

💡 Typical Applications

• Relay drivers
• Hammer drivers (e.g., printer mechanisms)
• Lamp drivers (incandescent or LED with appropriate resistors)
• Display drivers (LED and gas discharge)
• Line drivers
• Logic buffers

🛡️ Design Notes & Best Practices

• Do not exceed 500 mA per channel (600 mA peak) or the total 1 W package dissipation; consider thermal management for continuous high-current loads.
• Keep the output voltage within 50 V and ensure proper load and supply connections.
• For inductive loads, always connect the COM pin to the supply to leverage the integrated suppression diodes.
• Observe the specified operating temperature range (−20°C to +85°C) for reliable performance.

Whether you’re building a prototype on a breadboard or integrating into a production design, the ULN2003 offers a compact, proven solution for high-current switching in Arduino, Raspberry Pi, and general electronics applications.