FSTU3125MTCX

Overview

The FSTU3125MTCX is a high-speed CMOS TTL-compatible bus switch manufactured by Fairchild Semiconductor. It provides four independent 1-bit switches with separate output enable inputs, packaged in a TSSOP-20 form factor. The device allows inputs to connect to outputs without adding propagation delay or generating additional ground bounce noise. It features integrated undershoot hardened circuitry that protects against voltage differentials and prevents unintended switching during undershoot events.

Feature Summary

• Integrated undershoot protection for A and B ports
• Low on-resistance for minimal signal degradation
• Separate output enable control for each switch

Applications

• High-speed data bus interfacing
• Signal routing in digital systems
• Ground bounce reduction in parallel buses

Procurement Notes

Verify the specific suffix MTCX corresponds to the TSSOP-20 package configuration. Confirm lead-free status and RoHS compliance through official documentation. Ensure the ordering code matches the required operating temperature range of -40°C to +85°C.

Selection Notes

Select this component when low propagation delay and minimal ground bounce are critical requirements. The separate OE inputs allow precise control over individual bit paths. Verify compatibility with system voltage levels and ensure the TSSOP-20 package fits the PCB layout constraints.

Part Context

This part belongs to the FST3125 family of 4-bit bus switches. It shares functional similarities with other variants like FSTU3125 but utilizes a specific surface-mount package. The technology derives from Fairchild's proven switch design used in previous generations.

Replacement Considerations

Direct substitutes include FSTU3125M (SOIC-14) and FST3125MTC (TSSOP-20). Verify pinout compatibility and package dimensions before substitution.