SN74LS642-1N

Buffers, Drivers, Receivers, Transceivers Overview

The SN74LS642-1N is an octal bus transceiver from the Texas Instruments LS logic series, housed in a 20-pin PDIP package. It features open-collector outputs and operates with TTL input and output levels. The device supports bidirectional data transfer controlled by a direction signal. Electrical specifications include a minimum operating voltage of 4.75 V and a maximum of 5.25 V. Propagation delay is typically 25 ns at 5 V with a 45 pF load. Low-level output current is rated at 24 mA, while high-level output current is -15 mA.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Octal bus transceiver architecture providing eight independent bidirectional data channels
• Open-collector output configuration suitable for wired-OR applications
• Direction control pin manages data flow between port A and port B

Buffers, Drivers, Receivers, Transceivers Applications

• Bidirectional data bus interfacing between microprocessors and memory modules
• Wired-OR logic implementation on shared communication lines
• General-purpose digital data transmission in industrial control systems

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify that the specific ordering suffix '-1' corresponds to the required open-collector variant within the SN74LS642 family. Confirm package type matches the design requirements, as this part number specifies the PDIP through-hole option. Ensure compatibility with the system's power supply range of 4.75 V to 5.25 V before procurement.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when open-collector outputs are necessary for bus sharing or wired-OR functionality. The LS series offers standard propagation speeds suitable for general digital logic. Verify that the 20-pin PDIP package fits the available board space and assembly method constraints compared to surface-mount alternatives like the SOIC version.

Buffers, Drivers, Receivers, Transceivers Part Context

This device belongs to the SN74LS64x family of octal bus transceivers. It shares the same logical function as the SN74LS640 but differs in output stage design. While the SN74LS640 utilizes three-state outputs, the SN74LS642 employs open-collector outputs. This distinction dictates its suitability for specific bus topologies requiring active pull-down capabilities.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

SN74LS642N serves as the direct equivalent without the '-1' suffix designation.