KK74HC640A - Octal 3-State Inverting Bus Transceiver
TECHNICAL DATA KK74HC640A Octal 3-State Inverting Bus Transceiver High-Performance Silicon-Gate CMOS The KK74HC640A is identical in pinout to the LS/ALS640.
The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs.
The KK74HC640A is a 3-state transceiver that is used for 2-way asynchronous communication between data buses.
The device has an active-low Output Enable pin, which is used to place the I/O ports into high-impedanc