SN74HC164PWRE4 datasheet by Texas Instruments

SN74HC164PWRE4 Frequently Asked Questions (FAQs)

• What is the maximum clock frequency that can be used with this shift register?
  The maximum clock frequency for the SN74HC164PWRE4 is 100 MHz, but this can vary depending on the specific application and operating conditions. It's recommended to consult the datasheet and perform thorough testing to determine the maximum clock frequency for your specific use case.
• How do I ensure that the shift register is properly initialized on power-up?
  To ensure proper initialization, it's recommended to tie the CLR (clear) input low during power-up, and then release it after the power supply has stabilized. This will ensure that the shift register is reset to a known state. Additionally, you can use an external reset circuit or a power-on reset (POR) circuit to ensure a clean power-up sequence.
• Can I use this shift register with a 5V power supply?
  The SN74HC164PWRE4 is a 2V to 6V device, so it can operate with a 5V power supply. However, it's essential to ensure that the input signals are within the recommended voltage range (VCC - 0.5V to VCC + 0.5V) to prevent damage to the device.
• How do I handle the serial output (QH) when the shift register is not being clocked?
  When the shift register is not being clocked, the serial output (QH) will be in a high-impedance state. To prevent unwanted signals from being propagated, it's recommended to use a pull-down resistor or a bus holder circuit to keep the output low during idle periods.
• Can I use this shift register in a noisy environment?
  The SN74HC164PWRE4 has a relatively high noise immunity due to its CMOS design. However, it's still essential to follow proper PCB design and layout practices to minimize noise and ensure reliable operation. Additionally, you can use noise-reducing techniques such as shielding, filtering, and decoupling to further improve the device's noise immunity.