CD74HCT137E datasheet by Texas Instruments

CD74HCT137E Frequently Asked Questions (FAQs)

• What is the maximum clock frequency that can be used with CD74HCT137E?
  The maximum clock frequency for CD74HCT137E is 30 MHz, but it can vary depending on the operating voltage and load capacitance. It's recommended to check the timing characteristics in the datasheet and perform simulations to ensure the desired frequency can be achieved.
• How do I ensure that the CD74HCT137E outputs are not floating during power-up or power-down?
  To prevent floating outputs during power-up or power-down, it's recommended to add a pull-up or pull-down resistor to the output pins. This will ensure that the outputs are in a defined state even when the device is not powered or is in a power-down state.
• Can I use CD74HCT137E with a 5V power supply?
  The CD74HCT137E is a 4.5V to 5.5V device, so it can be used with a 5V power supply. However, it's essential to ensure that the input and output voltage levels are within the recommended operating conditions to prevent damage or malfunction.
• How do I handle the asynchronous reset input (MR) in CD74HCT137E?
  The asynchronous reset input (MR) should be tied to VCC through a pull-up resistor if it's not used. If it's used, ensure that the reset signal is synchronized with the clock signal to prevent metastability issues.
• What is the recommended termination for the CD74HCT137E outputs?
  The recommended termination for the CD74HCT137E outputs depends on the load and the desired signal integrity. In general, a series termination resistor (Rs) of 22-33 ohms is recommended, along with a parallel termination capacitor (Ct) of 10-20 pF.