74HCT85D,652

Comparators Overview

The Nexperia 74HCT85D,652 is a 4-bit magnitude comparator in the HCT logic series. It compares two 4-bit binary or BCD codes and outputs results for A>B, A=B, and A<B conditions. The device operates within a supply voltage range of 4.5 V to 5.5 V. It features TTL-compatible input levels and includes clamp diodes on inputs for interface flexibility. The component is housed in a 14-pin SO package (SO14) with a maximum propagation delay of 21 ns. It supports operation from -40 °C to +125 °C and complies with JEDEC standards.

Comparators Feature Summary

• Performs 4-bit magnitude comparison between two binary or BCD inputs
• Provides three distinct output signals indicating greater than, equal to, or less than relationships
• Features TTL-compatible input levels for direct interfacing with TTL logic systems
• Includes input clamp diodes to allow current-limiting resistor usage for voltages exceeding VCC

Comparators Applications

• Process controllers requiring data comparison
• Servo-motor control systems
• Support applications involving digital code validation

Comparators Procurement Notes

Verify end-of-life status carefully as some sources indicate obsolescence. Confirm package type is SO14 rather than SOIC-16 which may be a listing error. Ensure compatibility with 4.5V to 5.5V supply rails. Check for specific ordering suffixes if available. Validate datasheet version against manufacturer records before integration.

Comparators Selection Notes

Select this component when TTL-level inputs are required for 4-bit comparisons. It is suitable for designs needing expansion capabilities via cascading outputs. Consider thermal limits up to 125°C for industrial environments. Verify that the 21 ns delay meets system timing requirements. Ensure power supply stability within the specified 4.5V to 5.5V range.

Comparators Part Context

This part belongs to the 74HCT family of high-speed CMOS logic devices. It is functionally similar to the 74HC85 but with TTL-compatible inputs. The device is designed for general-purpose digital comparison tasks. It allows expansion to longer word lengths by cascading multiple units. The SO14 package provides a compact surface-mount solution.

Comparators Replacement Considerations

Public confirmed substitute part numbers: None identified.