SN74ALS243A

Supply voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, VI: All inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 V
I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5.5 V
Operating free-air temperature range, TA: SN54ALS243A . . . . . .55to 125
                                                                   SN74ALS243A . . . . . . . . . .0to 70
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 to 150

‡Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

These SN74ALS243A quadruple bus transceivers are designed for asynchronous two-way communication between data buses. The control-function implementation allows for maximum flexibility in timing. These SN74ALS243A 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 (OEBA and OEAB ) inputs. The output-enable inputs can be used to disable the device so that the buses are effectively isolated.

The dual-enable configuration gives the quadruple bus transceivers the capability to store data by simultaneously enabling OEBA and OEAB . Each output reinforces its input in this transceiver configuration. When both control inputs are enabled and all other data sources to the two sets of bus lines are at high impedance, both sets of bus lines (eight in all) retain their states. The 4-bit codes appearing on the two sets of buses are identical.The SN54ALS243A is characterized for operation over the full military temperature range of 55to 125. The SN74ALS243A is characterized for operation from 0to 70.