MC74ACT646N

Overview

The MC74ACT646N is an octal bus transceiver and register featuring 3-state outputs. It provides multiplexed transmission of data directly from the input bus or from internal storage registers. Data on the A or B bus loads into respective registers on the LOW-to-HIGH transition of the appropriate clock pin (CAB or CBA). The device operates at a supply voltage of 4.5 V to 5.5 V, with TTL compatible inputs for the ACT series.

Feature Summary

• Independent Registers for A and B Buses
• Multiplexed Real-Time and Stored Data Transfers
• Choice of True and Inverting Data Paths
• Outputs Source/Sink 24 mA

Applications

• Bus-oriented applications requiring registered data transfer
• Microprocessor interface systems
• Real-time and stored data handling circuits

Procurement Notes

Verify the specific package suffix 'N' against official ordering information. The datasheet lists SOIC-24 options (DW suffix) but does not explicitly confirm PDIP-20 availability in this document. Confirm RoHS compliance status and exact physical dimensions with the manufacturer before procurement.

Selection Notes

Select the MC74ACT646N when TTL-compatible inputs are required alongside high-speed octal bus transceiving capabilities. Ensure the application environment supports the specified 4.5 V to 5.5 V operating range and verify that the 24 mA output drive current meets the load requirements.

Part Context

This component belongs to the MC74AC/ACT646 family of registered bus transceivers. It integrates D-type flip-flops and control circuitry to allow flexible data routing between buses. The device supports both real-time transmission and data storage functions within a single integrated circuit package.

Replacement Considerations

MC74AC646 serves as a functional alternative without TTL-compatible inputs. Verify pinout compatibility and electrical specifications, particularly input voltage thresholds and propagation delays, before substituting.