Eight-bit shift registers with Schmitt-trigger inputs and with output registers

The SN74HCS594 device contains an 8-bit, serial-in, parallel-out shift

register that feeds an 8-bit D-type storage register. All inputs include Schmitt

triggers, eliminating any erroneous data outputs due to slow-edged or noisy input

signals. The storage register has parallel outputs. Separate clocks and direct

overriding clear (SRCLR, RCLR) inputs are

provided for both the shift and storage register. A serial output (QH’)

is provided for cascading.

Both the shift register (SRCLK) and storage register (RCLK) clocks are positive edge

triggered. If both clocks are connected together, the shift register is one count

pulse ahead of the storage register.