We use AD9915 for LO synthesis in one of our products. It seems that occasionally, the DAC calibration fails to work properly. This results in a variety of behaviors, but the most common is an overall raising of the noise floor. It is possible that we are doing something wrong, so I am posting a query here. I have a couple of questions:
1. What is recommended (and detailed) procedure for performing DAC calibration on AD9915? For example, is it important to keep CFR4 high for a specific duration?
2. Are there any things to watch out for wrt to DAC calibration? Any errata?
REF Input clock is 2.5GHz differential LVPECL signal levels. This signal is derived from a GPSDO.