FST3126M

Overview

The FST3126M is a 4-bit bus switch IC manufactured by onsemi, formerly Fairchild Semiconductor. It provides four high-speed CMOS TTL-compatible bus switches with low on-resistance to connect inputs to outputs without adding propagation delay or generating ground bounce noise. The device operates within a supply voltage range of 4.0V to 5.5V and supports an operating temperature range from -40°C to +85°C. It features minimal propagation delay, low quiescent supply current, and control inputs compatible with TTL levels.

Feature Summary

• Provides four independent 1-bit bus switches with separate output enable (OE) inputs for individual port control.
• Features low on-resistance switch connections that allow signal transmission without significant propagation delay or ground bounce noise generation.
• Control inputs are compatible with TTL logic levels, ensuring straightforward integration with standard digital systems.
• Operates in zero-bounce flow-through mode when enabled, maintaining signal integrity during data transfer.

Applications

• High-speed data bus switching in consumer electronics
• Signal routing in industrial control systems
• Interface bridging between different voltage domains in embedded systems

Procurement Notes

Verify the exact ordering code suffix against the official onsemi website, as part numbers may have been updated following the Fairchild Semiconductor integration. Ensure the selected package variant matches the required PCB footprint, such as SOIC-14 or TSSOP-14. Confirm compliance requirements including RoHS status and lead-free specifications before finalizing procurement orders.

Selection Notes

Select this component when designing circuits requiring low-latency signal routing between multiple ports. Consider the 4.0V to 5.5V operating voltage range and ensure compatibility with the system's logic levels. Evaluate the thermal performance within the specified -40°C to +85°C ambient temperature range for reliable operation in various environments.

Part Context

The FST3126M belongs to the FST series of bus switches, originally developed by Fairchild Semiconductor and now managed by onsemi. This series utilizes proven CMOS technology designed for high-speed applications. The device is part of a broader family of bus drivers and switches intended for efficient signal management in complex digital architectures.

Replacement Considerations

Check for equivalent parts within the FST3126 family, such as variants in QSOP or TSSOP packages, if pinout compatibility is required. Verify functional equivalence regarding on-resistance and propagation delay characteristics before substituting with other manufacturers' components.

FAQ

What is the maximum operating supply voltage for the FST3126M?

The recommended operating conditions specify a maximum supply voltage (VCC) of 5.5V.

How does the FST3126M handle unused control inputs?

Unused control inputs must be held either high or low; they may not float during operation.

Is the FST3126M suitable for use in life support devices?

No, ON Semiconductor products are not designed, intended, or authorized for use as critical components in life support systems without express written approval.