ADF4157 problem


I used ADF4157(fractional mode) with OP27 to control the VCO(DCMO190410)

I found that some noise were running on the Fout(desired frequency) its like modulated signal.

my design rule  as below

loop bandwidth=40KHz

phase margin =45 degree

filter type is active filter(inverting input for OP)


Vbias =2.5V ( Non-inverting port)