tea
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Dear Experts
i have a few questions on pll veriloga phase noise modeling.
i created voltage-domain VCODIV/PFDCP/OSC veriloga models based on Ken's paper: Predicting the Phase Noise and Jitter of PLL-Based Frequency Synthesizers. I bumped into some issues need your advice!!! Thank you!!
1) did i insert phase noise in the right way? if not, what is the right way?
i need to use noise transfer functions derived from Matlab based on design correlated phase noise-frequency pair. so my voltage outputs of OSC for example is like:
originally it was like this: vnoise = $rdist_normal(seed,0,1) * laplace_nd(V(in),{2.686e26,3.105e20}, {1.954e33, 9.858e27,1});
however, the full PLL PSS/Pnoise analysis can not take the hidden state 'seed' nor the 'state' variable in PFDCP model, Spectre RF errors out in PSS analysis I also tried to put the noise filter to a white_noise source, AC analysis can show the noise filter effect, not noise analysis
vnoise = laplace_nd(white_noise(1,"wpn")+V(in),{7.047e21,6.032e15 }, {6.646e28, 1.921e23,1});
V(out)<+ V(in)+vnoise;
so in short, i can only see the noise filter effect in AC analysis, i can not do PSS/Pnoise analysis on the full pll with voltage-domain models
2) it seems to me, i can only use AC analysis, not PSS/Pnoise analysis?
i am thinking i can try phase-domain models too, however, only AC analysis shows the noise filter effect; so i can only use AC analysis? i can not use PSS/Pnoise analysis for the full pll?
sorry if i asked silly questions, i kind of new to this pll noise analysis thing
thanks for your wisdom!
jasmine
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