CDCE949PWG4 datasheet by Texas Instruments

CDCE949PWG4 Frequently Asked Questions (FAQs)

• What is the recommended power-up sequence for the CDCE949PWG4?
  The recommended power-up sequence is to power up the VCC pin first, followed by the VCCPLL pin, and then the input clock signal. This ensures proper initialization and prevents any potential latch-up conditions.
• How do I configure the CDCE949PWG4 for a specific output frequency?
  The CDCE949PWG4 can be configured for a specific output frequency by setting the appropriate values for the M, N, and R dividers using the SPI interface. The TI-provided software tool, CDCE949 Evaluation Module, can be used to calculate the divider values and program the device.
• What is the maximum input clock frequency that the CDCE949PWG4 can handle?
  The maximum input clock frequency that the CDCE949PWG4 can handle is 350 MHz. However, the device can also accept input frequencies up to 700 MHz with an external divider or attenuator.
• How do I ensure proper thermal management for the CDCE949PWG4?
  Proper thermal management for the CDCE949PWG4 can be ensured by providing a heat sink or a thermal pad on the exposed pad of the QFN package, and ensuring good airflow around the device. The device's junction temperature should be kept below 125°C to ensure reliable operation.
• What is the purpose of the internal PLL loop filter, and how do I optimize it?
  The internal PLL loop filter is used to filter the PLL control voltage and ensure stable operation. The loop filter can be optimized by adjusting the values of the external resistors and capacitors connected to the FILT pin, based on the specific application requirements and clock frequency.