FST3257QSC

Overview

The FST3257QSC is a single-channel high-speed CMOS multiplexer/demultiplexer bus switch manufactured by Fairchild Semiconductor. It operates within the FST series and features a true output configuration housed in a 6-lead SC-70 package (specifically TSSOP/TSSOP6). The device functions as a 1-line to 1-line switch, providing TTL-compatible control inputs and low on-resistance characteristics suitable for signal routing applications.

Feature Summary

• Provides a single-channel multiplexer/demultiplexer function with true output logic
• Features low on-resistance for minimal propagation delay and reduced ground bounce noise
• Control inputs are compatible with TTL voltage levels
• Operates in flow-through mode with zero bounce characteristics

Applications

• Logic replacement in digital circuits
• Video, audio, and graphics signal switching
• Hot-swapping and hot-docking interface protection
• Voltage translation between different logic families
• Bus funneling and data routing

Procurement Notes

Verify the specific manufacturer source, as Fairchild Semiconductor's logic products have been transitioned to ON Semiconductor. Confirm that the QSC suffix corresponds to the required SC-70/TSSOP6 package variant and ensure compliance with current RoHS standards before procurement. Cross-reference datasheets from both entities to confirm pinout and electrical specifications match the design requirements.

Selection Notes

Select this component when a single-channel, high-speed analog or digital switch is required with minimal signal distortion. The FST3257QSC is appropriate for applications demanding low on-resistance and TTL-compatible control signals. Ensure the operating temperature range and supply voltage requirements align with the system specifications, considering the compact SC-70 footprint for space-constrained designs.

Part Context

The FST3257QSC belongs to the FST (Fast Switch Technology) family of bus switches. This series is characterized by high-speed operation and low power consumption, derived from Fairchild's proven switch technology. It serves as a specialized logic component designed for efficient signal routing and isolation in complex digital systems, distinct from standard logic gates or memory circuits.

Replacement Considerations

Equivalent parts include the FST3257M and FST3257MX from Fairchild/ON Semiconductor. Verify package compatibility, as the QSC suffix denotes a specific SC-70/TSSOP6 form factor. Ensure functional equivalence regarding channel count and control logic compatibility when substituting.