SN74ALS621A-1NS

Buffers, Drivers, Receivers, Transceivers Overview

The SN74ALS621A-1NS is an octal bus transceiver from the Texas Instruments ALS logic family, designed for asynchronous two-way communication between data buses. It features open-collector true outputs and a dual-enable configuration allowing flexible timing control. The -1 suffix indicates an increased recommended maximum low-level output current of 48 mA when VCC is between 4.75 V and 5.25 V. It operates within a supply voltage range of 4.5 V to 5.5 V and supports propagation delays up to 39 ns.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Provides asynchronous two-way communication capability between data buses with flexible timing control via dual-enable inputs.
• Features open-collector true outputs that reinforce input signals in a transceiver configuration.
• Includes local bus-latch capability by simultaneously enabling both OEAB and OEBA inputs to store data.

Buffers, Drivers, Receivers, Transceivers Applications

• Asynchronous two-way communication between data buses
• Local bus-latch applications requiring data storage capability
• Systems utilizing open-collector output configurations

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify the specific ordering suffix '-1' to confirm the device meets the requirement for the increased 48 mA low-level output current specification. Ensure the package type 'N' corresponds to the standard plastic DIP format required for the target application. Confirm RoHS compliance status and lead finish details against the latest manufacturer documentation before finalizing procurement.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when open-collector outputs are necessary for wired-AND configurations or interfacing with different voltage levels. The -1 version is specifically chosen over standard variants if the design requires higher low-level sink currents under specific supply voltage conditions. Consider the dual-enable feature for complex bus arbitration scenarios.

Buffers, Drivers, Receivers, Transceivers Part Context

This part belongs to the SN74ALS620A/621A/623A/AS623 series of octal bus transceivers. It shares the same functional architecture as the SN74ALS621AN but differs in electrical characteristics due to the -1 designation. The series is characterized for operation from 0°C to 70°C and is available in various package options including SOIC and PDIP.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

SN74ALS621AN serves as the standard equivalent without the enhanced current rating. SN74ALS620ADW offers similar functionality but with inverting 3-state outputs instead of open-collector true outputs.