54AC251WRQMLV

Overview

The 54AC251WRQMLV is a military-grade, single 8-input multiplexer manufactured by National Semiconductor. It utilizes AC-CMOS technology and features TRI-STATE outputs for bus-oriented applications. The device operates within a supply voltage range of 3.3 V to 5 V and supports a propagation delay of 17 ns at nominal supply. It is housed in a 20-pin ceramic chip carrier package (CQCC20) designed for high reliability. The component is qualified under MIL-PRF-38535 standards, ensuring performance across an extended temperature range from -55 °C to 125 °C.

Feature Summary

• Provides eight selectable data inputs routed to a single output with TRI-STATE capability
• Constructed using AC-CMOS process technology for high-speed switching
• Housed in a hermetically sealed ceramic chip carrier package suitable for harsh environments

Applications

• Military aerospace signal routing systems
• High-reliability industrial control data buses
• Radiation-hardened communication equipment

Procurement Notes

Verify the specific qualification suffix 'RQMLV' against the manufacturer's current MIL-PRF-38535 certified part list to confirm active status and radiation hardness levels. Ensure the ordering documentation explicitly references the ceramic package type and military temperature grade. Cross-reference the datasheet revision to confirm pinout compatibility with existing board layouts before procurement.

Selection Notes

Select this component when a single 8-to-1 multiplexing function is required in a space-constrained, high-reliability environment. The AC-CMOS technology offers a balance of speed and power consumption suitable for battery-operated or thermally sensitive military platforms. The TRI-STATE output allows multiple devices to share a common data bus without external isolation circuitry.

Part Context

This part belongs to the 54AC series of logic integrated circuits, which are the military-grade equivalents of the commercial 74AC family. The 54AC251 specifically functions as an 8-line to 1-line data selector. The 'WRQMLV' suffix indicates a specific wafer lot, lead finish, and quality level compliant with Department of Defense procurement requirements for space-qualified electronics.

Replacement Considerations

Direct replacements include the 54AC251LM or 54AC251J from National Semiconductor/TI. Other compatible parts include the 54F251ADM for faster switching speeds, though power consumption will differ. Verify that any substitute maintains the same ceramic package footprint and MIL-PRF-38535 qualification if environmental ruggedness is critical.