CD74HCT257M

Overview

The CD74HCT257M is a quad 2-input multiplexer from the HCT series, manufactured by Harris Corporation. It features buffered inputs and operates within a supply voltage range of 4.5V to 5.5V. The device utilizes CMOS technology and is housed in a 16-pin SOIC package. It supports synchronous operation with a typical propagation delay of 12ns at VCC = 5V and CL = 50 pF. The component is designed for high-speed digital signal routing applications.

Feature Summary

• Quad configuration providing four independent 2-to-1 data selection channels
• Buffered inputs ensure signal integrity and noise immunity
• Synchronous positive edge-triggered operation for precise timing control
• Compatible with standard TTL logic levels via HCT input structure

Applications

• Digital signal routing in microprocessor systems
• Data selection for analog-to-digital converter inputs
• Address decoding and bus switching circuits
• Logic function generation using data inputs as control signals

Procurement Notes

Verify RoHS compliance status as documentation indicates non-compliance. Confirm package variant matches project requirements (SOIC-16). Check lifecycle status for obsolescence risks. Ensure supply voltage aligns with system 5V rails. Validate operating temperature range against environmental specifications.

Selection Notes

Select this component when multiple independent 2:1 multiplexing functions are required in a single package. The HCT series ensures compatibility with 5V TTL logic families. Consider the 12ns propagation delay for timing-critical paths. Verify that the 16-pin SOIC footprint fits the PCB layout constraints.

Part Context

Part of the Harris 74HCT logic family, designed for high-speed CMOS applications with TTL-compatible inputs. The CD74HCT257M specifically addresses multi-channel data selection needs in digital systems. Harris Semiconductor was a key provider of logic ICs before industry consolidation.

Replacement Considerations

Check for direct pin-compatible equivalents from other manufacturers such as SN74HCT257. Verify electrical parameters match, especially propagation delay and supply voltage range. Ensure package dimensions are identical for board replacement.