SNAU279A July 2022 – September 2022
Another option is to feed an external clock to the XO SMA port (J8) to drive the XO input. See Figure 3-9. This path can be connected to the XO input pins. Y1 should be powered down when using the external XO input path. To power down Y1 and use an external XO input, the jumper on JP4 must be removed. Suggested XO frequencies for best device performance are frequencies of 38.88 MHz and 48 MHz. When using an external XO input, TI recommends to remove the capacitor (C71) connecting the TCXO output to the XO input of the LMK5B33414. This will prevent any risk of backdriving the onboard TCXO.