CD74HCT85E

Overview

The CD74HCT85E is a high-speed CMOS logic device functioning as a 4-bit magnitude comparator. It operates within a supply voltage range of 2V to 6V, with specific HCT variants supporting 4.5V to 5.5V. The component features non-inverting, active-high outputs and utilizes a 16-pin PDIP package for through-hole mounting. Key electrical characteristics include a maximum propagation delay of 33ns at specified load conditions and output currents of ±5.2mA. It supports an operating temperature range from -55°C to +125°C.

Feature Summary

• Performs 4-bit magnitude comparison between two binary words
• Provides cascading capability for expanding bit width comparisons
• Features high-speed CMOS technology compatible with TTL logic levels

Applications

• Digital arithmetic logic units requiring data comparison
• Address decoding systems in microprocessor interfaces
• Error detection circuits in digital communication protocols

Procurement Notes

Verify the exact suffix against the manufacturer datasheet to confirm voltage compatibility (HC vs HCT). Ensure the packaging type matches the design requirements, as surface mount and through-hole variants exist. Confirm that the selected part number aligns with the required operating temperature range and pin configuration before finalizing procurement orders.

Selection Notes

Select this component when a 4-bit comparator is needed with high-speed performance and wide voltage flexibility. The HC series offers broader voltage operation compared to HCT, which is optimized for 5V TTL compatibility. Consider the package style and thermal requirements relative to the target application environment.

Part Context

This device belongs to Texas Instruments' 74HC/74HCT logic family, designed for general-purpose digital applications. It provides a cost-effective solution for basic arithmetic operations and data validation tasks within embedded systems and industrial control equipment.

Replacement Considerations

Compatible substitutes include the SN74HC85N and SN74HCT85N from Texas Instruments. Other manufacturers may offer equivalent parts such as the MC74HC85A or MM74HC85C, provided pinouts and electrical specifications match.