FST3253MTC

Overview

The FST3253MTC is a dual 4:1 high-speed CMOS TTL-compatible multiplexer/demultiplexer bus switch manufactured by onsemi. It operates within a supply voltage range of 4.0V to 5.5V and supports an operating temperature range from -40°C to +85°C. The device features a typical switch on resistance of 4Ω at VCC=4.5V and provides minimal propagation delay through the switch. It utilizes a 16-lead Thin Shrink Small Outline Package (TSSOP) with a width of 4.4mm.

Feature Summary

• Dual 4:1 multiplexer/demultiplexer architecture enabling flexible signal routing between ports.
• Low on-resistance switch connection allows inputs to connect to outputs without adding propagation delay or generating additional ground bounce noise.
• Control inputs are compatible with TTL levels, ensuring seamless integration with standard logic families.
• Zero bounce operation in flow-through mode ensures stable signal transmission.

Applications

• High-speed data bus switching applications requiring low latency.
• Signal routing in systems utilizing TTL-compatible logic interfaces.
• Multiplexing and demultiplexing tasks in digital communication circuits.

Procurement Notes

Verify the specific package type and ordering suffix when sourcing components, as nomenclature may vary due to manufacturer integrations. Confirm that the device meets the required operating voltage and temperature specifications for your application environment. Ensure unused control inputs are held HIGH or LOW to prevent floating states during operation.

Selection Notes

Select this component for applications requiring a dual 4:1 bus switch with TTL compatibility and low on-resistance characteristics. Consider the TSSOP-16 package constraints regarding board space and thermal management. Validate that the supply voltage remains within the 4.0V to 5.5V range to ensure proper functionality and avoid exceeding absolute maximum ratings.

Part Context

The FST3253MTC belongs to the Fairchild Switch family, which derives from proven switch technology previously used in products like the 74LVX3L384. This lineage ensures reliability and performance consistency. The device is now part of the onsemi portfolio following the integration of Fairchild Semiconductor, maintaining its original functional specifications while adhering to updated system requirements.

Replacement Considerations

The datasheet lists the FST3253M as a variant available in a 16-Lead SOIC package. Verify pinout compatibility and package dimensions before substituting with other variants or cross-referenced parts from different manufacturers.

FAQ

What happens to the switch state when the OE input is HIGH?

When the OE (Output Enable) input is HIGH, the switch is OPEN, resulting in a high-impedance state existing between the two ports.

How are the A Port and B Port connected based on S0 and S1 inputs?

When OE is LOW, S0 and S1 select which B Port output connects to the A Port. For example, S0=L and S1=L connects A to B1, while S0=H and S1=H connects A to B4.