ULQ2003AN

Overview

The ULQ2003AN is a high-voltage, high-current Darlington transistor array manufactured by Texas Instruments. It integrates seven independent NPN Darlington pairs within a single package, each capable of sinking up to 500 mA of continuous current. The device features built-in clamping diodes across each input-output pair to suppress inductive voltage spikes when driving inductive loads such as relays or solenoids. Designed for operation with standard TTL or CMOS logic inputs, it provides direct interface capability without requiring external driver components. The unit operates from a supply voltage up to 50 V and is housed in a 16-pin dual in-line package.

Feature Summary

• Integrates seven independent high-voltage Darlington transistor pairs for multi-channel switching applications
• Includes internal flyback diodes connected between each input and collector to protect against inductive load transients
• Provides direct compatibility with TTL and CMOS logic families for simplified circuit design

Applications

• Driving stepper motors and relay coils
• Interface circuits for industrial control systems
• High-current switching for LED arrays and lamps

Procurement Notes

Verify the specific suffix 'AN' corresponds to the leaded plastic dual in-line package variant during sourcing. Confirm that the manufacturer designation matches Texas Instruments specifications to ensure correct pinout and electrical characteristics. Check for authenticity markers on the marking code to avoid counterfeit components.

Selection Notes

Select this component when multiple high-side or low-side switching channels are required in a compact form factor. Ensure the load current does not exceed the per-channel limit of 500 mA and consider thermal dissipation requirements for continuous operation. Verify that the logic family voltage levels match the input threshold requirements of the Darlington array.

Part Context

This part belongs to the ULQ200x series of Darlington arrays, which also includes variants like the ULN2003. The ULQ2003 differs primarily in its internal resistor configuration and diode placement compared to the ULN series. It is commonly used in legacy systems and industrial automation where robust inductive load handling is necessary.

Replacement Considerations

Direct substitutes include the ULN2003A for similar functionality with minor differences in internal resistance. Other compatible alternatives may include the TC4427 or SN75489 depending on specific voltage and current requirements. Always verify pin compatibility and thermal performance before substitution.