SN74ALS638A-1DWR

Buffers, Drivers, Receivers, Transceivers Overview

The SN74ALS638A-1DWR is an octal bus transceiver in the ALS logic series, housed in a 20-pin SOIC (DW) package. It facilitates asynchronous two-way communication between open-collector and 3-state buses. The A-bus outputs are open collector, while B-bus outputs are 3-state. Data transmission direction is controlled by the DIR input, allowing transfer from A to B or B to A. An OE input isolates the buses when disabled. This -1 version supports a maximum low-level output current of 48 mA at VCC between 4.75 V and 5.25 V. Operating voltage ranges from 4.5 V to 5.5 V, with an operating temperature range of 0°C to 70°C.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Bidirectional data transmission between open-collector A-bus and 3-state B-bus
• Direction control via DIR input for A-to-B or B-to-A flow
• Bus isolation capability through OE input
• -1 variant supports increased low-level output current

Buffers, Drivers, Receivers, Transceivers Applications

• Asynchronous communication interfaces between different bus types
• System architecture requiring bidirectional data routing
• Digital logic circuits utilizing mixed open-collector and 3-state signaling

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify the specific ordering suffix matches the required package type and tape/reel quantity. Confirm that the -1 designation aligns with design requirements for the specified 48 mA low-level output current limit. Ensure supply chain sources provide documentation confirming RoHS compliance and lead finish specifications as listed in the manufacturer's packaging addendum.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when interfacing between open-collector and 3-state buses within the ALS logic family. The -1 suffix indicates enhanced low-level drive capability compared to standard versions. Consider the SOIC package dimensions and thermal characteristics for PCB layout. Verify compatibility with system voltage levels and temperature constraints before integration.

Buffers, Drivers, Receivers, Transceivers Part Context

This device belongs to the Texas Instruments SN74ALS638A/639A octal bus transceiver family. It shares functional similarities with the SN74AS638A but offers distinct electrical characteristics suited for specific load conditions. The product line provides options for true or inverting logic configurations across various package styles including DIP and SOIC.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

SN74ALS638ADW is available in tube packaging instead of tape and reel.