Modeling of irregular shaped power distribution planes using transmission matrix method

A major problem in power distribution networks is simultaneous switching noise (SSN), which causes several signal integrity issues. To understand the behavior of the power distribution system (PDS) and its contribution to SSN, noise prediction methods are necessary. This paper presents a method for analyzing arbitrary shaped power distribution networks both in the frequency and time domain. Using a two dimensional array of distributed RLCG circuits, the impedance of a power/ground plane pair is computed. For the efficient computation of the power distribution impedances at specific points in the network, a multi-input and multi-output transmission matrix method has been used. To verify the accuracy of this method, the simulation results have been compared with Spice which uses a circuit based approach and an analytical solution based on the cavity modes in the structure. The simulation results have also been compared with measurements for an L-shaped structure. The transmission matrix method has been applied to a split plane and an arbitrary shaped power plane to demonstrate the application of this technique to irregular geometries.