SN74ALS645ANSR

Buffers, Drivers, Receivers, Transceivers Overview

The SN74ALS645ANSR is an octal bus transceiver from the Texas Instruments ALS logic family, housed in a 20-pin Small Outline (NS) package. It supports bidirectional asynchronous data communication between two buses with three-state outputs. The device operates on a supply voltage ranging from 4.5 V to 5.5 V and functions within a temperature range of 0°C to 70°C. Propagation delays are specified between 1 ns and 19 ns depending on signal direction and control states.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Bidirectional data transmission capability controlled by a dedicated direction input
• Three-state outputs allowing effective isolation of buses when disabled
• Octal configuration providing eight independent data paths per device

Buffers, Drivers, Receivers, Transceivers Applications

• Asynchronous two-way communication between data buses
• Bus-oriented memory and logic transfers
• High-density system designs requiring bidirectional data routing

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify that the specific ordering suffix matches the required package type and lead finish. Confirm RoHS compliance status for environmental regulations. Ensure the operating temperature range aligns with the intended application environment. Check for any specific material or packaging requirements mandated by the design specifications.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component for applications requiring high-density octal bus interfacing. The ALS series offers a balance of speed and power consumption suitable for standard digital systems. Consider the 20-pin SOIC footprint for board space constraints. Verify that the 3-state output characteristics meet the bus loading requirements of the connected components.

Buffers, Drivers, Receivers, Transceivers Part Context

This part belongs to the SN54/74ALS645A family of octal bus transceivers. It shares functional similarities with other ALS series devices but is distinct in its bidirectional octal architecture. The 'ANSR' suffix indicates a specific surface-mount plastic small-outline package variant produced for high-volume manufacturing.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

SN74ALS645ADWR

Buffers, Drivers, Receivers, Transceivers FAQ

How is the data flow direction determined?

Data flow is controlled by the DIR input; a low level directs data from the A bus to the B bus, while a high level directs data from the B bus to the A bus.

What happens when the OE input is high?

When the Output Enable (OE) input is high, the device enters an isolation state, effectively disconnecting the outputs from the buses regardless of the direction setting.