ULQ2804A

Overview

The ULQ2804A is an octal Darlington transistor array manufactured by STMicroelectronics. It integrates eight NPN Darlington pairs with common emitters and includes integral suppression diodes designed for driving inductive loads. The device features a 10.5 kΩ input resistor, making it suitable for interfacing with 6-15 V CMOS logic families. Each channel supports a continuous collector current of 500 mA and can withstand up to 50 V in the off state. The component operates within an extended temperature range from -40 °C to +105 °C and is housed in an 18-lead plastic DIP package.

Feature Summary

• Integrates eight Darlington transistors with common emitters and built-in suppression diodes for inductive load protection
• Includes a 10.5 kΩ input resistor optimized for direct interface with 6-15 V CMOS logic families
• Features an input-opposite-output pinout configuration to simplify printed circuit board layout

Applications

• Driving inductive loads such as relays, solenoids, and motors
• Interfacing microcontrollers or logic circuits with high-current devices
• General-purpose switching applications requiring high gain and isolation

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official datasheet to ensure correct packaging and tape-and-reel specifications. Confirm RoHS compliance status through the latest product change notifications. Check for any recent pinout revisions or thermal derating requirements before finalizing procurement orders.

Selection Notes

Select the ULQ2804A when interfacing with 6-15 V CMOS logic due to its integrated 10.5 kΩ input resistors. Choose this part over other ULQ variants if the application requires compatibility with standard CMOS voltage levels rather than TTL or PMOS interfaces. Ensure the 500 mA per-channel current rating meets the load requirements.

Part Context

The ULQ2804A belongs to the ULQ2801A-ULQ2804A family of octal Darlington arrays. These components are designed to simplify the interface between low-power logic circuits and higher-power loads. The family offers various input resistor configurations to match different logic standards, with the ULQ2804A specifically tailored for 6-15 V CMOS applications.

Replacement Considerations

Check for ULQ2804 equivalents from other manufacturers that maintain the same 18-pin DIP footprint and 10.5 kΩ input resistance. Verify that substitute parts offer identical 500 mA continuous current ratings and 50 V blocking voltage capabilities.