M74HC623B1R

Overview

The M74HC623B1R is an octal bus transceiver with 3-state outputs, fabricated using silicon gate CMOS technology. It facilitates two-way asynchronous communication between data buses. The device operates within a supply voltage range of 2V to 6V and features symmetrical output impedance with a minimum drive capability of 6mA. Propagation delay is typically 10ns at 6V. Quiescent supply current is maximized at 8µA across the full operating temperature range of -55°C to +125°C.

Feature Summary

• Supports bidirectional data transmission between A and B buses
• Provides high-impedance state for effective bus isolation
• Capable of data storage when both direction controls are enabled simultaneously

Applications

• Two-way asynchronous communication between data buses
• Bus-oriented memory and signal buffering
• Data routing in microprocessor systems

Procurement Notes

Verify component authenticity through official STMicroelectronics channels or authorized distributors. Confirm package type matches design requirements, as DIP, SOP, and TSSOP variants exist. Check RoHS compliance status and ensure the obsolete product status does not conflict with long-term availability needs.

Selection Notes

Select this component for applications requiring flexible bidirectional data flow control. Ensure the system logic levels align with the specified input/output voltage ranges. Consider the wide operating temperature range if the environment exceeds standard commercial limits.

Part Context

This part belongs to the M74HC series of advanced high-speed CMOS logic devices. It is functionally compatible with the 74LS623 series but offers lower power consumption and wider voltage operation. The 'B1R' suffix indicates the specific tube packaging format for the DIP variant.

Replacement Considerations

CD74HC623E (Texas Instruments)

FAQ

How does the M74HC623B1R isolate the buses?

The buses are isolated by setting either GBA or GAB inputs to a high logic level, which places all outputs in a high-impedance state.

What is the maximum quiescent supply current?

The maximum quiescent supply current is 8µA at 6V across the full operating temperature range.