SN74HC594DG4 datasheet by Texas Instruments

SN74HC594DG4 Frequently Asked Questions (FAQs)

• What is the maximum clock frequency that can be used with the SN74HC594DG4?
  The maximum clock frequency is typically limited by the rise and fall times of the clock signal, but Texas Instruments recommends a maximum clock frequency of 25 MHz for the SN74HC594DG4.
• Can I use the SN74HC594DG4 with a 5V power supply?
  Yes, the SN74HC594DG4 is compatible with 5V power supplies, but it can also operate with power supplies as low as 2V. However, the output voltage levels may not be as high with lower power supply voltages.
• How do I ensure that the shift register is properly reset after power-up?
  The SN74HC594DG4 has an asynchronous reset input (SRCLR) that can be used to reset the shift register. It's recommended to tie this input to the power supply voltage through a pull-up resistor and add a capacitor to ground to ensure a clean reset signal during power-up.
• Can I use the SN74HC594DG4 to drive LEDs or other high-current loads?
  No, the SN74HC594DG4 is not designed to drive high-current loads. The output current is limited to 25 mA per output pin, and the device is intended for use as a logic-level shift register. If you need to drive high-current loads, you should use an external driver or buffer.
• How do I handle the latency of the shift register when clocking in data?
  The SN74HC594DG4 has a latency of 1 clock cycle between the clock input and the output of the shift register. This means that the data will be delayed by 1 clock cycle before it appears at the output. You should take this latency into account when designing your system and ensure that the clock frequency is sufficient to accommodate the latency.