Supply original MC74AC646DWR2G, Logic - Buffers, Drivers, Receivers, Transceivers, by ON Semiconductor

Octal Transceiver/Register with 3-State Outputs (Non-inverting)
The MC74AC646/74ACT646 consist of registered bus transceiver circuits, with outputs, D−type flip−flops and control circuitry providing multiplexed transmission of data directly from the input bus or from the internal storage registers. Data on the A or B bus will be loaded into the respective registers on the LOW−to−HIGH transition of the appropriate clock pin (CAB or CBA).
The four fundamental data handling functions available are illustrated Figures 1 to 4.
Features
• Independent Registers for A and B Buses
• Multiplexed Real−Time and Stored Data Transfers
• Choice of True and Inverting Data Paths
• 3−State Outputs
• 300 mil Slim Dual In−Line Package
• Outputs Source/Sink 24 mA
• ′ACT646 Has TTL Compatible Inputs
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These are Pb−Free Devices