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ADF4158 FMCW loop filter without ADIsimPLL

Question asked by kzalesak on Jul 23, 2017
Latest reply on Jul 23, 2017 by PeterW

Dear Community,


I am designing a PLL system to be used in FMCW radar. I need a sweep with the following parameters:


200-400 MHz (200 MHz BW)

1s sweep time

5kHz step



Reference TXCO 10MHz


I need to design a loop filter with as little phase noise as possible.

I have tried using ADIsimPLL to simulate my PLL, however my ramp requires 40 000 steps and at that amount ADIsimPLL is slow to the point of not usable and/or crashes. 


Is there any other way that I could design a loop filter? Is there a rule of thumb that I can use and then fidget around? Is there something that I am doing wrong within ADIsimPLL?

My configuration is posted as an attachment.


I have the ADF4159 on-board VCO eval board if that is of any help.


Thank you very much for your help!