Wide Operating Voltage Range of 2 V to 6 V

High-Current 3-State Outputs Can Drive Up

To 15 LSTTL Loads

Low Power Consumption, 80-μA Max ICC

Typical tpd = 8 ns

±6-mA Output Drive at 5 V

Low Input Current of 1 μA Max

Lock Bus-Latch Capability

True Logic

description/ordering information

These octal bus transceivers are designed for

asynchronous two-way communication between

data buses. The control-function implementation

allows for maximum flexibility in timing.

The ’HC623 devices allow data transmission from

the A bus to the B bus or from the B bus to the A

bus, depending upon the logic levels at the

output-enable (OEAB and OEBA) inputs.

OEAB and OEBA disable the device so that the

buses are effectively isolated. The dual-enable

configuration gives the transceivers the capability

to store data by simultaneously enabling OEAB

and OEBA. Each output reinforces its input in this

transceiver configuration. When both OEAB and

OEBA are enabled and all other data sources to

the two sets of bus lines are in the high-impedance

state, both sets of bus lines (16 total) remain at

their last states. The 8-bit codes appearing on the

two sets of buses are identical.