IN74HC651A

The IN74HC651A is identical in pinout to the LS/ALS651. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs.

These devices of the IN74HC651A consist of bus transceiver circuits, D-type flip-flop, and control circuitry arranged for multiplex ransmission of data directly from the data bus or from the internal storage registers. Direction and Output Enable are provided to ct the read-time or stored data function. Data on the A or B Data bus, or both, can be stored in the internal D flip-flops w-to-high transitions at the appropriate clock pins (A-to-B Clock or B-to-A Clock) regardless of the select or enable or able control pins. When A-to-B Source and B-to-A Source are in the real-time transfer mode, it is also possible to store data t using the internal D-type flip-flops by simulta-neously enabling Direction and Output Enable. In this configuration each t reinforces its input. Thus, when all other data sources to the two sets of bus lines are at high impedance, each set of s lines will remain at its last state.

The IN74HC651A has inverted outputs.