MC74ACT646DWR2G

Overview

The MC74ACT646DWR2G is an octal registered bus transceiver with three-state outputs in a 24-lead SOIC package. It operates on a 4.5 V to 5.5 V supply and features TTL-compatible inputs. The device provides multiplexed transmission of data directly from the input bus or internal storage registers via D-type flip-flops. Data loads on the LOW-to-HIGH clock transition. Propagation delay reaches 18.5 ns at 50 pF load. Outputs source and sink 24 mA.

Feature Summary

• Multiplexed real-time and stored data transfers between A and B buses
• Independent registers for A and B buses with D-type flip-flops
• TTL compatible inputs for direct interface with TTL logic systems

Applications

• Registered bus transceivers
• Memory register interfaces
• I/O adapters

Procurement Notes

Verify the specific ordering suffix 'DWR2G' confirms the SOIC-24 tape and reel packaging format containing 1000 units per reel. Confirm the ACT series designation ensures compatibility with 4.5 V to 5.5 V power supplies and TTL input thresholds. Ensure the component meets lead-free RoHS compliance standards as indicated by the G suffix.

Selection Notes

Select this component when designing systems requiring simultaneous registered and real-time data transfer across two independent 8-bit buses. The ACT series is appropriate for applications needing TTL-compatible inputs while maintaining CMOS output drive capabilities. Verify that the 24 mA output current capability meets the load requirements of the connected circuitry.

Part Context

This part belongs to the MC74AC/ACT646 family of octal bus transceivers manufactured by onsemi. It integrates eight D-type flip-flops with control circuitry to manage data flow between external buses and internal registers. The device supports both true and inverting data paths, providing flexibility in system architecture design.

Replacement Considerations

MC74ACT646DWG

FAQ

How does the device handle data loading?

Data on the A or B bus loads into the respective registers on the LOW-to-HIGH transition of the appropriate clock pin (CAB or CBA).

What are the input voltage threshold characteristics?

The ACT version features TTL-compatible inputs, allowing operation with standard TTL logic levels within the specified 4.5 V to 5.5 V supply range.