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Simulators >> RF Simulators >> Can pnoise capture component variation due to noise leading to AM-FM conversion
https://designers-guide.org/forum/YaBB.pl?num=1217107774

Message started by paidian on Jul 26^th, 2008, 2:29pm

Title: Can pnoise capture component variation due to noise leading to AM-FM conversion
Post by paidian on Jul 26^th, 2008, 2:29pm

In LC VCOs, small-signal noise from various noise generators (bias current ,gm pair etc.) reach the tank and modulate the tank components mainly varactors diodes etc. The noise sources also change the amplitude of the oscillating signal and result in changing tank capacitance slightly. This mechanism changes frequency of oscillation as a function of small-signal noise resulting in AM-FM conversion.

My question is: Does pnoise capture this effect correctly?

Based on what I read about PSS and PNOISE, at each large signal operating condition, simulator generates a linear circuit and computes the transfer function of the noise at that bias point to the output. It does not talk about capacitor variation (or component variation) due to noise.