A package analysis tool based on a method of moments surface formulation

A package analysis tool that is based on a method of moments analysis and surface formulation is described. The surface formulation replaces ideal conductors by electric currents on their surfaces, while electric and magnetic currents are used for lossy conductors. These currents are then discretized using triangular linear current approximations, with the primary advantage of being able to represent arbitrary shapes. Frequency-dependent inductance and resistance are computed. The capacitance is also computed using piecewise-constant charge distributions on each triangle. The current and charge distributions are compatible, and therefore transmission line modeling can be done accurately. The algorithm allows use of the tool for both transmission line and discontinuity modeling, as well as analysis of simultaneous switching noise. The tool has a graphical pre- and postprocessor, which allows analysis of highly irregular structures, are found in most practical packaging configurations. An analysis of simultaneous switching noise for a 304-lead, six-layer single-chip module is presented as an example