General description
The 74ABT646A high-performance BiCMOS device combines low static and dynamic power dissipation with high speed and high output drive.
The 74ABT646A transceiver/register consists of bus transceiver circuits with 3-state outputs, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the input bus or the internal registers. Data on the A bus or B bus will be clocked into the registers as the appropriate clock pin (CPAB or CPBA) goes HIGH.
Output Enable (OE) and Direction (DIR) pins are provided to control the transceiver function. In the transceiver mode, data present at the high-impedance port may be stored in either the A or B register or both.

Features and benefits
■ Combines 74ABT245 and 74ABT373A type functions in one device
■ Independent registers for A and B buses
■ Multiplexed real-time and stored data
■ Live insertion and extraction permitted
■ Output capability: +64 mA to −32 mA
■ Power-up 3-state
■ Power-up reset
■ Latch-up protection exceeds 500 mA per JESD78B class II level A
■ ESD protection:
   ♦ HBM JESD22-A114F exceeds 2000 V
   ♦ MM JESD22-A115-A exceeds 200 V