Accurate models for Frequency Synthesizers

An accurate Noise description in behavioral models for Fractional-N Frequency Synthesizers is presented. It is demonstrated that a noise-addition-like synthesizerpsilas model yields a better Phase-Noise prediction than a time-domain jitter model. This allows a more direct analysis of the noise contribution of every circuit in the Frequency Synthesizers and avoids simulation inaccuracies when very low Phase-Noise designs are held.