8-Bit Shift Registers With 3-State Output Registers

The SNx4HC595 devices contain an 8-bit, serial-in,

parallel-out shift register that feeds an 8-bit D-type storage register. The storage

register has parallel 3-state outputs. Separate clocks are provided for both the

shift and storage register. The shift register has a direct overriding clear

(SRCLR) input, serial (SER) input, and serial outputs for

cascading. When the output-enable (OE) input is high, the

outputs are in the high-impedance state.