SN74HC594 - 8-Bit Shift Registers With Output Registers

The SNx4HC594 devices contain an 8-bit serial-in, parallel-out shift register that feeds an 8-bit D-type storage register. Separate clocks and direct overriding clear (RCLR, SRCLR) inputs are provided on both the shift and storage registers. A serial (Q_H’) output is provided for cascading purposes.

Both the shift register (SRCLK) and storage register (RCLK) clocks are positive edge triggered. If both clocks are connected together, the shift register always is one count pulse ahead of the storage register.

The parallel (Q_A – Q_H) outputs have high-current capability. Q_H’ is a standard output.

• Wide Operating Voltage Range of 2 V to 6 V
• High-Current Outputs Can Drive up to
  15 LSTTL Loads
• Low Power Consumption, 80-µA Maximum I_CC
• Typical t_pd = 15 ns
• ±6-mA Output Drive at 5 V
• Low Input Current of 1 µA Maximum
• 8-Bit Serial-In, Parallel-Out Shift Registers With
  Storage
• Independent Direct Overriding Clears on Shift and
  Storage Registers
• Independent Clocks for Both Shift and
  Storage Registers