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AD9914  PLL not working

Question asked by puppy on Mar 25, 2017
Latest reply on Apr 9, 2017 by puppy

Hey,I'm a new user of AD9914. Recently,I encountered some problems with using PLL of AD9914..

My external clock is 100MHz,and I hope to dpuble it to 2450MHz as system clock.And the output is 25.0375MHz.

So I enable RDIV 4 to divided 100MHz to 25MHz,then I set N=49,So the system clock is 25 * 49 * 2 = 2450MHz.

But when I measured the the SYNC_CLK,there was no 102MHz singnal . When I measured the pin 59 ,it was 1.8v (default 2.05V ),also ,there was no output singal .So I think the PLL of my AD9914 not working well..Here is my configuration of register. 

Hope sb can help me,and find what's wrong with my DDS, thanks a lot!