74FCT521ASCX

Overview

The 74FCT521ASCX is an 8-bit identity comparator manufactured by National Semiconductor, housed in a 20-SOP package. It functions as a magnitude comparator with active low outputs indicating A=B equality. The device operates within a supply voltage range of 4.75V to 5.25V and supports surface mount installation. It features true TTL input and output compatibility, ensuring seamless integration with standard logic families while maintaining CMOS power consumption levels.

Feature Summary

• Provides 8-bit identity comparison functionality with active low output signaling for equality detection
• Ensures true TTL input and output compatibility for direct interface with standard logic systems
• Maintains low input and output leakage currents to support efficient CMOS power level operation

Applications

• Digital data path equality verification
• Address bus matching in microprocessor systems
• Data integrity checking in communication interfaces

Procurement Notes

Verify component authenticity through official manufacturer channels or authorized distributors. Confirm RoHS compliance status and moisture sensitivity level prior to procurement. Check for obsolescence notices or product change notifications that may affect long-term availability. Ensure packaging specifications match assembly requirements.

Selection Notes

Select this component when 8-bit parallel data comparison is required with TTL-compatible I/O levels. Consider the 20-SOP package for surface mount applications requiring compact footprint. Evaluate propagation delay characteristics against system timing constraints. Verify operating temperature range suitability for the intended environmental conditions.

Part Context

This part belongs to the 74FCT logic family, designed for high-speed CMOS applications with TTL compatibility. The 74FCT521 series specifically addresses identity comparison needs in digital systems. National Semiconductor's implementation provides reliable performance for data validation tasks in computing and communication hardware.

Replacement Considerations

IDT74FCT521 variants offer equivalent functionality from Integrated Device Technology. Cross-reference pinouts and electrical specifications before substitution. Verify package dimensions and thermal characteristics match existing board layout constraints.