SN74LS688DWR

Overview

The SN74LS688DWR is an 8-bit magnitude and identity comparator manufactured by Texas Instruments. It operates within a supply voltage range of 4.85V to 5.25V. The device features active low outputs that indicate equality when inputs A equal B. It utilizes a 20-SOIC surface-mount package. Maximum propagation delay is specified at 23ns under conditions of 5V supply and 45pF load capacitance. Output current capabilities include 400µA for high state and 24mA for low state. Operating temperature ranges from 0°C to 70°C.

Feature Summary

• Performs 8-bit magnitude comparison between two binary words
• Provides active low output signal indicating input equality
• Supports cascading for multi-word comparison applications

Applications

• Digital address decoding systems
• Data validation circuits requiring equality checks
• Control logic for comparing setpoints against measured values

Procurement Notes

Verify the specific suffix DWR indicates the SOIC-20 tape and reel packaging configuration. Confirm RoHS compliance status as per manufacturer documentation. Ensure the operating environment remains within the specified 0°C to 70°C temperature range. Validate that the 5V supply voltage aligns with system requirements before integration.

Selection Notes

Select this component for standard TTL-compatible logic levels requiring 8-bit comparison. Consider the 23ns propagation delay for timing constraints in the target circuit. Evaluate the 20-SOIC footprint against available PCB space. Compare performance against HC series alternatives if lower power consumption or wider voltage ranges are required.

Part Context

This part belongs to the SN74LS688 family of 8-bit comparators. It is designed for general-purpose digital logic applications. The LS technology offers moderate speed with standard power dissipation characteristics. It serves as a fundamental building block for arithmetic logic units and control systems.

Replacement Considerations

SN74LS688DWRE4 is an equivalent variant with identical electrical specifications. Verify pin compatibility and package dimensions when substituting. Ensure thermal management requirements remain consistent across replacements.