M74HCT652RM13TR

Overview

The M74HCT652RM13TR is an octal bus transceiver and register with 3-state outputs, manufactured by STMicroelectronics. It operates within a supply voltage range of 4.5V to 5.5V. The device features a maximum clock frequency (fMAX) of 55 MHz at VCC = 4.5V and a typical propagation delay of 30 ns for bus-to-bus transmission. Quiescent supply current (ICC) is typically 4 μA at 25°C. It utilizes a 24-pin SOIC package.

Feature Summary

• Octal Bus Transceiver/Register: Combines bus transceiver circuits with D-type flip-flops for multiplexed data transmission from input buses or internal storage registers.
• Independent Direction Control: Features separate enable pins (GAB, GBA) to independently control the direction of data flow between the A and B buses.
• Real-Time vs. Stored Data Selection: Includes select pins (SAB, SBA) that allow users to choose whether real-time bus data or previously stored register data is transferred.
• Edge-Triggered Storage: Internal D flip-flops capture data on low-to-high transitions of dedicated clock inputs (CAB, CBA), independent of select or enable states.

Applications

• Multiplexed data transmission systems requiring bidirectional bus interfacing
• Digital logic designs needing simultaneous real-time and registered data routing
• Memory interface circuits utilizing 3-state output buffering

Procurement Notes

Verify component authenticity through official STMicroelectronics channels or authorized distributors. Confirm the specific ordering suffix RM13TR corresponds to the SOIC-24 tape-and-reel packaging. Check datasheet revisions for any updates to electrical characteristics or mechanical dimensions before finalizing procurement specifications.

Selection Notes

Select this component when designing systems requiring an octal wide bus interface with integrated storage capabilities. Ensure the operating environment stays within the specified -55°C to 125°C temperature range. Verify that the 4.5V to 5.5V supply voltage aligns with the system's power architecture and that TTL-compatible input levels are sufficient for signal integrity.

Part Context

This part belongs to the 74HCT series of advanced high-speed CMOS logic devices. It is functionally compatible with the standard 74LS652 but offers improved speed and lower power consumption due to its silicon gate C2MOS fabrication technology. The device provides robust protection against static discharge and transient excess voltage on all inputs.

Replacement Considerations

Check for direct pin-compatible alternatives such as the M74HCT652B1R (DIP) or M74HCT652TTR (TSSOP) if package changes are acceptable. Verify that substitute components maintain the same 3-state output characteristics and HCT logic level compatibility.

FAQ

How does the device handle data storage during bus operations?

Data on the A or B bus can be stored in internal D flip-flops via low-to-high transitions on the respective clock pins (CAB or CBA), regardless of the state of the select or enable control pins.

What determines whether real-time or stored data appears on the outputs?

The Select AB (SAB) and Select BA (SBA) pins determine the data source. A low input level selects real-time data transfer, while a high input level selects data stored in the internal registers.