Overview

The IDT74FCT521T is an 8-bit identity comparator that compares two words of up to eight bits each and provides a low output when the two words match bit for bit. The expansion input IA = B also serves as an active low enable input. The 74FCT521T operates at -40 °C to +85 °C.

74FCT521T - Block Diagram
74FCT521T - Block Diagram
  • A and C speeds
  • Low input and output leakage ≤1µA (max.)
  • CMOS power levels
  • True TTL input and output compatibility
  • VOH = 3.3V (typ.)
  • VOL = 0.3V (typ.)
  • High drive outputs (-15mA IOH, 48mA IOL)
  • Meets or exceeds JEDEC standard 18 specifications
  • Power off disable outputs permit "live insertion"
  • Available in 20-pin SOIC and QSOP packages

Documentation

Design & Development

ECAD Models

Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on products in the Product Options table. If a symbol or model isn't available, it can be requested directly from the website.

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Diagram of ECAD Models

Product Options

    Processing table
    Pkg. Type
    Lead Count (#)
    Temp. Grade
    Pb (Lead) Free
    Carrier Type
    Moisture Sensitivity Level (MSL)
    Price (USD) | 1ku
    Buy / Sample
    Part Number
    74FCT521ATQG
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    Samples Available
    		 QSOP 20 C Yes Tube 1 1.614 Get Samples,
    74FCT521ATQG8
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    		QSOP 20 C Yes Reel 1 1.547
    74FCT521ATSOG
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    Samples Available
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    		SOIC 20 C Yes Tube 1 Get Samples,
    74FCT521ATSOG8
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    		SOIC 20 C Yes Reel 1 1.547
    74FCT521CTQG
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    Samples Available
    		 QSOP 20 C Yes Tube 1 1.614 Get Samples,
    74FCT521CTSOG8
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    		SOIC 20 C Yes Reel 1 1.547
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