I have recently purchased a HMC8364 VCO and a ADF41513 PLL as it is recommended from Analog Devices.
Additionally, for the PLL the required/suggested evaluation board EV-ADF41513SD1Z is used.I successfully connected the VCO with the PLL and using the evaluation board of the PLL, high quality tones in the operetional ferequency range can be generated.
However after capturing the produced tone with a high spectral resolution ESA we observe tha the signal/tone appears a frequency drift of order of 500-700Hz. The produced tones are not locked in a specific frequency but they drift up and down (in the range of: 500-700Hz)from a center frequency. This frequency drifts apears both when the PLL operates on intenger and on fractional mode.
I wanted to ask if this frequency drift is normal or not. Can I eliminate or reduce this drift?
Can this drift be related to the values we set in the EVALUATION BOARD SOFTWARE of the PLL? or in a specific register?
Thank you in advance,