ULQ2004AD

Overview

The ULQ2004AD is a high-voltage, high-current Darlington transistor array manufactured by Texas Instruments. It integrates seven independent NPN Darlington pairs within a single package, providing a total collector current capability of 300 mA per channel and a maximum continuous collector current of 300 mA. The device supports a maximum collector-emitter voltage (Vceo) of 50 V and a maximum collector-base voltage (VCBO) of 50 V. It operates within a temperature range of -20°C to +70°C and is housed in a 16-pin SOIC-Narrow surface-mount package with a maximum power dissipation of 2 W.

Feature Summary

• Integrates seven independent NPN Darlington transistor pairs for multi-channel switching applications
• Features built-in clamping flyback diodes across each output to protect against inductive load back-EMF
• Designed for direct interface with TTL, CMOS, or MOS logic families without requiring external driver components

Applications

• Driving relays and solenoids in industrial control systems
• Actuating stepper motors and other inductive loads
• General-purpose high-voltage switching circuits

Procurement Notes

Verify the specific manufacturer source and authenticity before procurement, as component availability may vary. Confirm that the package type matches the required PCB footprint and soldering profile. Ensure compliance with relevant environmental standards such as RoHS directives applicable to the manufacturing region. Check for any end-of-life notifications or discontinuation notices from the supplier.

Selection Notes

Select this component when multiple independent high-side switches are required in a compact form factor. The integrated flyback diodes simplify circuit design for inductive loads. Consider the thermal management requirements due to the 2 W power dissipation limit. Verify that the 50 V voltage rating meets the system's maximum operating conditions.

Part Context

The ULQ2004AD belongs to the ULQ2004 series of Darlington arrays from Texas Instruments. This series is designed for robust switching applications requiring high voltage and current handling capabilities. It serves as a bridge between low-power logic controllers and high-power actuators, simplifying the interface design by integrating necessary protection components directly into the semiconductor package.

Replacement Considerations

The ULN2004AD is a functionally similar alternative from Texas Instruments. Verify pin compatibility and electrical specifications before substitution. Other compatible parts include the ULQ2004ADR and ULN2003A, depending on the number of channels required.