74F521DC

Overview

The National Semiconductor 74F521DC is an 8-bit identity comparator from the 74F series. It provides an active low output when input A equals input B. The device features a maximum propagation delay of 10ns at 5V with 50pF load. Output currents are specified as 1mA high and 20mA low. It operates within a temperature range of 0°C to 70°C and is supplied in bulk packaging.

Feature Summary

• Performs 8-bit magnitude comparison for identity detection
• Provides active low logic output for equality conditions
• High-speed operation with 10ns propagation delay

Applications

• Digital arithmetic circuits requiring data validation
• System address matching and decoding
• Data bus integrity verification

Procurement Notes

Verify the suffix DC indicates surface mount packaging and bulk supply. Confirm National Semiconductor origin, now part of Texas Instruments. Ensure compatibility with 74F series voltage levels. Check operating temperature range requirements against application specifications before ordering.

Selection Notes

Select this component for applications requiring fast 8-bit identity comparison. Consider the active low output polarity and current drive capabilities. Verify package type suitability for the intended mounting method. Compare propagation delay specifications against system timing constraints to ensure signal integrity.

Part Context

This part belongs to the 74F logic family, known for high-speed performance. It serves as a digital comparator within arithmetic and control circuits. The device complements other 74F series components for complex digital systems. It is functionally similar to the 74F521PC variant.