SN74LS644DW

Buffers, Drivers, Receivers, Transceivers Overview

The SN74LS644DW is an octal bus transceiver from Texas Instruments' LS logic series, housed in a 20-pin SOIC package. It features open collector outputs with TTL input and output levels. Key electrical parameters include a propagation delay of 25 ns, low-level output current of 24 mA, and high-level output current of -15 mA. The device operates within a supply voltage range of 4.75 V to 5.25 V and supports temperatures from 0°C to +70°C.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Octal bus transceiver architecture providing eight independent data channels
• Open collector output configuration suitable for wired-OR applications
• TTL-compatible input and output voltage levels

Buffers, Drivers, Receivers, Transceivers Applications

• Bidirectional data transmission between buses
• Memory interface circuits
• I/O port expansion systems

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify the specific suffix 'DW' corresponds to the SOIC-20 surface mount package variant. Confirm RoHS compliance status through official documentation as indicated in supplier listings. Ensure the application environment remains within the specified 0°C to +70°C operating temperature range to maintain performance specifications.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when an octal bidirectional buffer with open collector outputs is required. The LS logic family offers standard speed characteristics suitable for general-purpose digital interfaces. Consider the 20-pin SOIC footprint for PCB layout compatibility. Verify that the load capacitance requirements align with the specified 25 ns propagation delay at 5V.

Buffers, Drivers, Receivers, Transceivers Part Context

This part belongs to the SN74LS642/644 family of octal bus transceivers. While functionally similar to the SN74LS642, the SN74LS644 specifically utilizes open collector outputs rather than standard three-state outputs. Both share the same SOIC-20 packaging and LS logic electrical characteristics.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

The SN74LS642DW serves as a functional substitute but provides three-state outputs instead of open collector. Direct replacement requires verifying if the circuit design accommodates the change from open collector to three-state logic behavior.