Power-Bus Sensitivity Analysis

Design of modern printed circuit boards requires robust simulation techniques to model power-bus structures. A reliable method is the cavity model which assumes small spacing between power and ground planes. Designers often make the proper tradeoffs between conflicting design requirements using optimization techniques, to obtain the best possible performance. To this aim, sensitivity information with respect to power-bus parameters are required by optimizers which employ gradient-based techniques and need the knowledge of sensitivities of the output responses. In this paper, the sensitivity analysis of power-bus structures is presented. Relying on the cavity model, voltage sensitivity is computed in a rational function form or rational polynomial form leading to a time-domain macromodel which can be efficiently interfaced with linear and nonlinear terminations or Spice-like simulators. The simulation results show the accuracy of the proposed approach.