I am using the LMX2572 in a wide temperature range. Starting the operation at room temperature the PLL frequently goes out of lock at temperatures below -35°C (no problems at high temperatures up to the datasheet limits). If I send nothing but a CAL command to register 0 PLL is back in lock again without any problems. To my suprise I observe that the relevant registers R16, R19 and R20 contain the same values before and after the event. Loosing PLL lock therefore seems not to be primarily a CAL issue.
Since lock loss and the following CAL command causes bit errors and sometimes even a frame loss in my data stream it would be good to know the mechanism behind to find some cure. Any idea someone?
Thank you
Holger
