ULN2002D

Overview

The ULN2002D is a monolithic integrated high-voltage, high-current Darlington array IC manufactured by UMW. It contains five independent Darlington drive channels within a single package. Each channel features an internal freewheeling diode designed to handle inductive loads such as relays and stepping motors. The device supports a collector output current of 500 mA per channel, with multiple channels capable of parallel connection for higher current capacity. It operates with a collector-emitter voltage rating of 50 V and withstands input voltages up to 30 V. The circuit includes built-in series base resistors and pull-down resistances to ground, ensuring compatibility with TTL/CMOS logic signals under 5V operation.

Feature Summary

• Integrates five independent Darlington drive channels with common emitter configuration
• Includes internal freewheeling diodes for safe driving of inductive loads
• Features built-in series base resistors and 4K pull-down resistances to ground
• Directly interfaces with TTL and CMOS logic circuits without additional buffering

Applications

• Relay drive circuits
• Stepping motor drive systems
• LED display screen drivers
• Logic buffer applications

Procurement Notes

Verify the specific manufacturer source when sourcing this component, as datasheet details may vary between suppliers. Confirm that the SOP-14 package matches your PCB footprint requirements. Ensure the ordering suffix corresponds to the tape and reel delivery mode if required for automated assembly processes. Cross-reference electrical parameters against your system's maximum operating conditions.

Selection Notes

Select the ULN2002D when five-channel switching capability is required for moderate current loads. This component is suitable for designs needing direct interface with standard logic families like TTL or CMOS at 5V. Consider the thermal dissipation characteristics if multiple channels are driven simultaneously at high currents. Verify that the 50V voltage rating meets the requirements of the connected inductive loads.

Part Context

The ULN2002D belongs to the ULN20xx series of high-voltage Darlington arrays produced by UMW. Unlike other variants in the family that may offer different channel counts or voltage ratings, this specific model provides exactly five channels. It shares functional similarities with other industry-standard Darlington arrays but is distinct in its pinout and internal resistance configurations tailored for specific logic interfacing needs.

Replacement Considerations

Check for electrically equivalent Darlington arrays with five channels and similar voltage/current ratings. Verify pin-to-pin compatibility in SOP-14 packages before substitution. Ensure replacement parts maintain the same internal resistor values and clamp diode specifications to preserve circuit functionality.