AnsweredAssumed Answered

AD9524 PLL2 don't lock at low temperature

Question asked by des00 on Sep 11, 2012
Latest reply on Nov 16, 2012 by MFelmlee

Hi All !!!


I'm using AD9524 PLL2 to generate 5 clocks 64MHz from 32MHz cristal oscillator. All work fine at my table. But I have problem in heat chamber at low temperature.


When AD9524 is locked at -10 degrees, for example and cool up to -40 degrees all work fine, but when AD9524 is power on at -40 degrees PLL2 don't lock at all %(. And need to warm up AD9524 to -20 degrees to bring it work again.


PLL2 settings is


Loop BW 251kHz, Phase Margin 65.2deg, Zero Loc 63.7kHz, PoleLock 1.38MHz, Last Pole Lock 67MHz.


Cristal oscilator i using is Rakon TXO725E with specified working temperature is -40...+85. AD9524 specified working temperature is -40...+85 too, but it don't worked. What i do wrong ?


Thanks a lot!!!