Dear technical support,
I'am debuging the ADF4356. But there are very strong spurs as high as -66dBc
It's my own board.
LoopFilter bandwidth is 40KHz,
f_ref = 140MHz, R_div = 2, f_pfd = 70MHz, Icp = 0.9mA
In this photo,f_vco = 4050MHz,10MHz away from f_pfd's integer boundary.
IBS is far away from the carrier frequency. When the carrier frequency is 30MHz away form f_pfd's integer boundary, it's about -78dBc. I can't tolerate it.
I have searched for the answer for a long time and tried many ways. I hope you can help me .
Thank you very much.