incol
Full Member level 2
Hi, everyone
I am simulating the noise of PFD/CP. I add the same phase and frequency(20MHz) inputs to the PFD, and do the PSS+Pnoise simulation, plot the noise on the CP's output.The result is OK, nosie at 10KHz is 8pA. But when increasing the input frequency to 200MHz, the nosie at 10KHz increases to about 80pA,most contribution is flick nosie from PFD. Why the noise is influenced by the input frequency? Isn't this nosie the device itself?
I am simulating the noise of PFD/CP. I add the same phase and frequency(20MHz) inputs to the PFD, and do the PSS+Pnoise simulation, plot the noise on the CP's output.The result is OK, nosie at 10KHz is 8pA. But when increasing the input frequency to 200MHz, the nosie at 10KHz increases to about 80pA,most contribution is flick nosie from PFD. Why the noise is influenced by the input frequency? Isn't this nosie the device itself?