8-Bit Bidirectional Universal Shift Register with Parallel I/O High-Speed Silicon-Gate CMOS

The IN74AC323 is identical in pinout to the LS/ALS323, HC/HCT323. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALS outputs.

The IN74AC323 features a multiplexed parallel input/output data port to achieve full 8-bit handling in a 20 pin package. Due to the large output drive capability and the 3-state feature, this device is ideally suited for interface with bus lines in a bus-oriented system.

Two Mode-Select inputs and two Output Enable inputs are used to choose the mode of operation as listed in the Function Table. Synchronous parallel loading is accomplished by taking both Mode Select lines, S1 and S2, high. This places the outputs in the high impedance state, which permits data applied to the data port to be clocked into the register. Reading out of the register can be accomplished when the outputs are enabled. The active-low synchronous Reset overrides all other inputs.

• Outputs Directly Interface to CMOS, NMOS, and TTL

• Operating Voltage Range: 2.0 to 6.0 V

• Low Input Current: 1.0 μA; 0.1 μA @ 25°C

• High Noise Immunity Characteristic of CMOS Devices

• Outputs Source/Sink 24 mA