ULN2064B

Overview

The ULN2064B is a quad Darlington transistor array manufactured by STMicroelectronics, designed to interface logic circuits with high-current and high-voltage loads. It contains four NPN Darlington switches delivering up to 1.5 A per channel, with a specified minimum breakdown voltage of 50 V and a sustaining voltage of 35 V measured at 100 mA. The device features integral suppression diodes for inductive load protection and common emitters. Inputs are compatible with popular 5 V logic families. It is housed in a Power DIP-16 package for through-hole installation, with a maximum continuous collector current of 1.75 A, a maximum collector-emitter saturation voltage of 1.4 V, and a maximum power dissipation of 4.3 W.

Feature Summary

• Contains four NPN Darlington switches for driving high-current loads
• Includes integral suppression diodes suitable for inductive loads
• Input compatibility with standard 5 V logic families
• Common emitter configuration across all channels

Applications

• Interface between logic circuits and high-current loads
• Driving inductive loads such as relays or solenoids
• High-voltage switching applications requiring isolation from control logic

Procurement Notes

Verify the specific manufacturer part number against official STMicroelectronics documentation to ensure authenticity. Confirm that the component matches the required Power DIP-16 package and through-hole mounting specifications. Check for any ordering suffixes that may indicate variations in packaging or temperature range, ensuring they align with project requirements without altering functional characteristics.

Selection Notes

Select this component when interfacing 5 V logic with loads requiring up to 1.5 A at voltages up to 50 V. Ensure thermal management capabilities accommodate the 4.3 W power dissipation rating. Verify that the common emitter topology and integral flyback diodes meet the circuit design needs for inductive load handling.

Part Context

The ULN2064B belongs to the ULN206x series of quad Darlington switches from STMicroelectronics. This family includes variants like the ULN2066B and ULN2068B, which differ in input voltage compatibility and pre-driver stages. The ULN2064B specifically targets 5 V logic interfaces, distinguishing it from CMOS/PMOS compatible versions within the same product line.

Replacement Considerations

Direct substitutes within the same STMicroelectronics family include the ULN2066B and ULN2068B, though input voltage compatibility differs. Cross-manufacturer equivalents should be verified for pinout compatibility, current ratings, and voltage breakdown specifications.