Q1.How should I design the LPF of ADF4106 when producing a range of equal spaced
output frequency? PD=250kHz?output frequency: 2000-4000MHz?using active loop
filter configuration, OP184. I tried to use ADISIMPLL to simulate, it can give
the result but I am not sure whether the Loop Filter's value need to be
modified when the output frequency is changed?
2.How about the min PD and channel spacing of ADF4106 ?
3.Can +24V power-supply voltage of OP184 make sure the output:OP184 VOH>=18V?
A1. This depends on the VCO's Kv. if Kv is changed from one frequency to
another, then you will see different loop bandwidth and phase margin result
(with the same loop filter value).
If VCO's Kv is vary a lot, it may cause the loop to become unstable at that
frequency, you can change the ICP to compensate for the Kv changes.
2. Detector phase is nominally input frequency divided by R.
3. When the power supply is single 5V, the signal range is GND+0.125 to
VDD-0.15V (as the figures),so it is OK for your requirement.