SN74HCT74DBR datasheet by Texas Instruments

SN74HCT74DBR Frequently Asked Questions (FAQs)

• What is the maximum clock frequency that the SN74HCT74DBR can handle?
  The maximum clock frequency of the SN74HCT74DBR is 30 MHz, but it can vary depending on the operating conditions and the quality of the clock signal.
• How do I ensure that the flip-flops are properly initialized on power-up?
  To ensure proper initialization, connect the preset (PRE) and clear (CLR) inputs to a valid logic level (either VCC or GND) through a pull-up or pull-down resistor. This will ensure that the flip-flops are set to a known state on power-up.
• What is the recommended operating voltage range for the SN74HCT74DBR?
  The recommended operating voltage range for the SN74HCT74DBR is 4.5V to 5.5V, with a typical operating voltage of 5V.
• Can I use the SN74HCT74DBR in a 3.3V system?
  While the SN74HCT74DBR is specified for 5V operation, it can be used in a 3.3V system with some limitations. However, the device's performance and noise immunity may be degraded at lower voltages. It's recommended to consult the datasheet and perform thorough testing to ensure reliable operation.
• How do I handle the asynchronous preset and clear inputs?
  The preset and clear inputs are asynchronous, meaning they can be asserted at any time, regardless of the clock signal. To avoid unintended behavior, ensure that these inputs are synchronized with the clock signal or use them only during power-up or reset conditions.