ULN2004 7-Channel Darlington Sink Driver IC

The ULN2004 is a high-voltage, high-current Darlington array with seven open collector Darlington pairs and common emitters on each side. Each channel can handle peak currents of 600 mA and is rated at 500 mA. For increased current capability, the Darlington pairs can be paralleled. For inductive load driving, suppression diodes were used, and the inputs were pinned opposite the outputs to make board layout easier. ULN2001 (general-purpose, DTL, TTL, PMOS, CMOS); ULN2002 (14 – 25 V PMOS); ULN2003 (5 V TTL, CMOS); ULN2004 (general-purpose, DTL, TTL, PMOS, CMOS); ULN2005 (general-purpose, DTL, TTL, PMOS, CMOS); ULN2006 (general-purpose, DTL, TTL, PMOS, CMOS (6 – 15 V CMOS, PMOS).

These versatile devices may, among other things, power solenoids, relay DC motors, LED display filament lights, thermal printheads, and high-power buffers. The ULN2004A is housed in a 16-pin DIP package with a copper lead frame to reduce heat resistance. They’re also available in the compact outline packaging as ULN2004D1 (SO-16).

Darlington transistor arrays with high voltage and current are used in the ULx2004 devices. Each one is made up of seven NPN Darlington pairs with high-voltage outputs and inductive load-switching common-cathode clamp diodes. A 10.5-k series base resistor is included in the ULx2004A devices to allow direct operation from CMOS devices running at 6 V to 15 V supply voltages. The ULx2004A device has a lower input current need than the ULx2003A device, as well as a lower voltage requirement than the ULN2002A device.

Applications

• Relay Drivers
• Stepper and DC Brushed Motor Drivers
• Lamp Drivers
•  Display Drivers (LED and Gas Discharge)
• Line Drivers
•  Logic Buffers