ULN2003AING4

Overview

The ULN2003AING4 is a high-voltage, high-current Darlington transistor array manufactured by Texas Instruments. It integrates seven NPN Darlington pairs within a single monolithic integrated circuit, designed for driving heavy loads directly from logic inputs. The device features a 16-lead Thin Shrink Small Outline Package (TSSOP) suitable for surface-mount applications. Each channel provides a continuous collector current of 500 mA and can withstand off-state voltages up to 50 V. Internal series input resistors allow direct interfacing with 5 V TTL or CMOS logic families without external components.

Feature Summary

• Integrates seven independent high-voltage Darlington transistor channels for multi-load control
• Includes internal clamp diodes on each output to suppress inductive kickback from reactive loads
• Features built-in series input resistors enabling direct connection to standard logic gates
• Provides open-collector outputs capable of sinking significant load currents

Applications

• Relay driver circuits for switching power loads
• Stepper motor coil drivers in positioning systems
• High-current LED display multiplexing arrays
• Logic buffer interfaces between low-power controllers and peripheral devices

Procurement Notes

Verify the specific suffix 'ING4' against the manufacturer's official documentation to confirm RoHS compliance status and exact package dimensions. Ensure the ordering part number matches the required TSSOP-16 variant rather than the standard PDIP version. Cross-reference the datasheet revision date to confirm pinout compatibility with existing board layouts before finalizing procurement orders.

Selection Notes

Select this component when surface-mount space constraints require a compact solution compared to traditional DIP packages. The ULN2003AING4 offers identical electrical performance to its through-hole counterparts but utilizes a smaller footprint. Consider thermal dissipation requirements carefully, as the TSSOP package has lower thermal capacity than larger packages. Verify that the 50V voltage rating meets the maximum load requirements of the specific application design.

Part Context

This component belongs to the ULN20xxA family of Darlington arrays produced by Texas Instruments. The 'I' designation indicates the Thin Shrink Small Outline Package (TSSOP), while 'NG4' typically denotes lead-free construction and environmental compliance. This series is widely used in industrial automation and consumer electronics where reliable switching of inductive loads is required.

Replacement Considerations

The ULN2003APWR is a compatible surface-mount alternative from Texas Instruments using a PowerPAD package. Other manufacturers such as STMicroelectronics offer the ULN2003ADTR in a similar TSSOP-16 form factor. Verify pin-to-pin compatibility and thermal characteristics before substituting these parts in existing designs.