HD74HC323 Datasheet, PDF (1/10 Pages) Hitachi Semiconductor – 8-bit Universal Shift/Storage Register (with 3-state Outputs)

HD74HC323
8-bit Universal Shift/Storage Register (with 3-state Outputs)
Description
This eight-bit universal register features multiplexed I/O ports to achieve full eight bit data handling in a
single 20-pin package. HD74HC323 applications are as stacked or push-down registers, buffer storage, and
accumulator registers.
Two function-select inputs and two output control inputs can be used to choose the modes of operation
listed in the function table.
Synchronous parallel loading is accomplished by taking both function-select lines S₀ and S₁ high. This
places the three-state outputs in a high-impedance state, which permits data that is applied on the I/O ports
to be clocked into the register. Reading out of this register can be accomplished while the outputs are
enabled in any mode. The clear function is synchronous, and a low level at the clear input clears the
register on the next low-to-high transition of the clock.
Features
• High Speed Operation: t_pd (Clock to Q) = 20 ns typ (C_L = 50 pF)
• High Output Current: Fanout of 15 LSTTL Loads
• Wide Operating Voltage: V_CC = 2 to 6 V
• Low Input Current: 1 µA max
• Low Quiescent Supply Current: I_CC (static) = 4 µA max (Ta = 25°C)