Fast and accurate analysis of supply noise effects in PLL with noise interactions

Using behavioral models to perform fast simulation is currently a popular solution to verify SOC designs. Previous analog behavior modeling approaches often treat the noisy V_DD waveform as a given input and focus on reflecting such stimuli on circuit performance. However, because the interaction of noise aggressors and victims is not considered, some error may exist while compared with real simulation results. In this paper, a simple SCORE macromodel is proposed for PLL designs to help noiseaware behavioral models handle supply noise interaction effects. The time-varying supply noise waveform and real-time PLL responses can be obtained simultaneously with accurate noise estimations in this recursive approach. As demonstrated in the experimental results, the proposed approach can provide more realistic results with noise interaction effects but still keep fast simulation time.