Hello Andy,
Thanks for your replay.
I am playing around PLL average models, comparing results with time models. Using MODULATE won't give AC response but using BV with V=
sin(2*pi*(fc*time+df*idt(V(m)))) works for both, time and frequency analysis.?
My long term goal is to model the integer boundary spurs of a (fractional) PLL. Because of the frequency division I need square wave vco, which is not the problem. The problem is to have average model of a duty cycle for integer or fractional division. I am trying zero order hold laplace, COMB/MAF filters, etc, inserting them into averaged model here and there.
And again, because I am not sure how to do it, I do comparison with the time models. Something like this:
/g/LTspice/files/Temp/phase_mod2za.asc
Probably my approach is not the right one.
Cheers
