Modeling of Multilayered Power/Ground Planes Based on Resonant Cavity Algorithm

Based on the resonant cavity algorithm, a method is presented to model the multilayered power/ground planes with stitching vias at the high-speed packages and the printed circuit board. A multilayered structure can be seen as a combination of two basic units: adjacent planes with a different reference voltage and that with the same reference voltage. Then, the behaviors of the switching current in and the physics-based models for the multilayered power/ground planes with different basic units are presented. By analyzing the influence of stitching vias to the return path of the switching current in the multilayered structure, it is obtained that the remainder plane pairs act as a multiport load to the plane pair where the current load is located on. The algorithm for a plane pair with a multiport load is presented on the basis of the resonant cavity algorithm to efficient mode the multilayered power/ground planes. At the same time, this modeling method can be used in auto-decoupling design to consider the placements of decoupling capacitors. The modeling method is corroborated by the comparison with a 3-D electromagnetic commercial tool with wideband Z-parameter computation from dc to 10 GHz.