Thank you very much for your useful answer.
I have still a couple of questions:
1) Which is the best opamp you may suggest to keep the phase noise as low as possible?
2) I am missing the reason why the phase detector gain is set to 2 V/rad in the main window. This is my reasoning:
a) Each port of the phase detector balanced output (UN and UD) swings 2 Vpp for 2pi radians. The balanced signal should thus swing 4 Vpp for 2pi radians, thus approx. 0,64 V/rad. Where am I wrong?
Thanks again and best regards.
Forum admin note, this question was branched from:
Simulation models for HMC699 (PLL) with HMC583 (VCO)
1) ADA4084 is a good part which could keep a low phase noise performance.
2)Per the datasheet, the PFD gain here is 0.32V/rad. For synthesizers with PFD output, you could put 2 in the phase detector gain box. The software will take care of it. You could consider the box here s in unit Vpp/2pi.