A SCORE macromodel for PLL designs to analyze supply noise interaction issues at behavioral level

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 errors may exist in the simulation. In this paper, a simple SCORE macromodel is proposed for PLL designs. It can be integrated with a supply-noise-aware PLL behavioral model to analyze supply noise effects at high level. In addition to numerical results, the time-varying supply noise waveform and real-time PLL responses can be obtained simultaneously. As demonstrated in the experimental results, the proposed approach can provide more realistic simulation results with noise interaction effects but still keep fast simulation time.