Efficient DC and AC Impedance Calculation for Arbitrary-Shape and Multilayer PDN Using Boundary Integration

Abstract

This article presents an efficient methodology based on boundary integration to calculate the dc and ac impedance of power distribution networks (PDNs) for arbitrary-shape and multilayer printed circuit boards (PCBs). The proposed method adopts a boundary element method to extract inductances for the arbitrary parallel-plane shapes. Subsequently, the equivalent circuit formed by the via inductances and plane capacitances is solved using the node voltage method. By merging the parallel and serial inductances and simplifying the equivalent circuit, the computation time can be significantly reduced for a large number of vias and layers. This matrix manipulation strategy can be applied to various PCB structures without human intervention or commercial circuit solvers. Moreover, a contour integral method is employed to calculate the dc resistances for arbitrary shape and multilayer PDNs. Therefore, the wideband PDN impedance from dc to ac frequencies can be efficiently calculated through 1-D boundary integration, which can be performed more quickly than full-wave simulations. The proposed method can aid in the development of electronic design automation tools for PDN design.