74FST3345QSR

Overview

The onsemi 74FST3345QSR is an 8-bit high-performance bus switch designed for CMOS and TTL compatibility within a 4.0 V to 5.5 V supply voltage range. It features extremely low on-resistance (RON) of typically 4 Ω at 4.5 V, ensuring nearly zero propagation delay with a maximum of 0.25 ns. The device incorporates two output enable pins (OE1 and OE2) for flexible control. It operates across a temperature range of -40°C to +85°C and offers negligible standby current and no circuit bounce.

Feature Summary

• Provides 8-bit bidirectional switching capability with minimal signal distortion
• Features dual independent output enable inputs for precise channel control
• Maintains CMOS and TTL logic compatibility across the operating voltage range
• Delivers ultra-low propagation delay and near-zero quiescent power consumption

Applications

• High-speed data bus switching in telecommunications equipment
• Signal routing in consumer electronics and mobile devices
• Data distribution networks requiring low latency and isolation
• Peripheral interface management in industrial automation systems

Procurement Notes

Verify that the specific suffix 'QS' corresponds to the QSOP-20 package variant when sourcing. Confirm RoHS compliance status as standard packages may vary by manufacturing lot. Ensure the ordering number matches the required tape and reel or rail quantity specifications provided in the official documentation. Cross-reference the datasheet revision date to confirm technical parameters align with current production standards.

Selection Notes

Select this component for applications requiring fast switching speeds and low insertion loss. The dual enable pins allow for complex bus arbitration topologies. Verify that the load capacitance and drive strength requirements fall within the specified electrical characteristics. Consider the available package options based on board space constraints and thermal management needs for the target environment.

Part Context

This device belongs to the FST (Fast Switching Technology) logic family from onsemi. It serves as a direct replacement for similar 8-bit bus switches like the FST3345 and QS3345. The technology focuses on minimizing signal integrity issues such as ground bounce and crosstalk in high-density digital circuits.

Replacement Considerations

Pin-for-pin compatible substitutes include the FST3345, QS3345, and CBT3345. Verify that alternative parts meet the same 4.0V to 5.5V operating voltage and -40°C to +85°C temperature range specifications before implementation.