In my project , i use ADF4159&ADF5901 to make the chirp signal for radar. if the chirp time is 100us,the Bandwidth is 250MHz, the PFD is 100MHz,and the frequecny step is 400Hz. i find that i can not cal the register of ADF4159. Because the clk1 & clk2 of ADF4159 can not be smalller than 1 . So if the step number is too large, the sweep time can not be satisfied.
So if i want to sweeep 100us in 250MHz span, the minimum frequency step is 5KHz.
Does is it correct?
Look forward for your reply.