Safal,
Some of the default configuration has the CDCE62005 in buffer mode, and require external clock.
There are some settings configuring the CDCE62005 in synthesizer mode and utilizes the on-board 19.2MHz crystal oscillator as reference. The example settings can be found in the DAC348x GUI
C:\Program Files (x86)\Texas Instruments\DAC348x\EVM Configuration File Released\DAC3484\Example CDCE62005 PLL Configuration
-Kang