SN74HC688PWRE4

Overview

The SN74HC688PWRE4 is an 8-bit identity comparator manufactured by Texas Instruments, housed in a 20-pin TSSOP package. It performs comparisons of two 8-bit binary or BCD words to determine equality (A = B). The device features active-low outputs and includes an output-enable input. Operating parameters include a supply voltage range of 2 V to 6 V and an operating temperature range of -40°C to +85°C. Propagation delays are specified at 210 ns, 42 ns, and 36 ns.

Feature Summary

• Performs identity comparison of two 8-bit binary or BCD words
• Features active-low outputs for equality indication
• Includes an output-enable input for bus control

Applications

• Digital data validation circuits
• Address decoding systems
• Memory parity checking

Procurement Notes

Verify the specific suffix 'E4' indicates lead-free compliance and RoHS status as per manufacturer documentation. Confirm the TSSOP-20 package dimensions match PCB footprint requirements. Ensure supply voltage levels align with the 2 V to 6 V operational range. Check that propagation delay specifications meet system timing constraints. Validate temperature ratings against environmental conditions.

Selection Notes

Select this component when 8-bit equality detection is required within the HC logic family voltage range. The TSSOP-20 package suits surface-mount assembly processes. Consider the active-low output polarity for interface compatibility with downstream logic gates. Verify that the propagation delay characteristics satisfy the maximum clock frequency of the application design.

Part Context

This part belongs to the SN74HC688 series of 8-bit identity comparators from Texas Instruments. It is part of the broader SNx4HCxx high-speed CMOS logic product line. The device provides digital comparison functionality using standard CMOS technology compatible with various logic families.

Replacement Considerations

SN74HC688DWRG4 offers identical electrical performance in a SOIC-20 package. SN74HC688PWRT is available in a TSSOP-20 package without the E4 suffix variant.