ADF4156 Phase Resync Operation

I am having a problem that the output phase can only keep its relation to

the ref phase for about one minute after phase resync operation. How can I

make sure the phase relation is matched all the time? I followed the

calculation on the datasheet. It seems to be it only talk about the shortest

time I can sync the phase. It is true that once I done phase resync during

startup the phase relation should always be kept? I

ok thanks for the block diagram - I think in this case if the Reference divider = 1, then you should get close to zero phase difference

between RFout and REfin. There is a finite propagation delay through the divider chain which will cause an offset, this is in the order

of a few hundred ps according to Ian Collin's article I pasted the link for above. This might be acceptable depending on the carrier frequency.

If R is not equal to 1, then I think the phase could appear at any +/- 360deg/R intervals depending on which edge of the reference the divider

starts counting. You should draw out the signal timing for the case where R=2 and N=3, you will see that there are two possible phases the

RF output will have relative to the reference.

What is the carrier frequency in this case ? There might be a more suitable part than the ADF4156 that would allow R=1.