Effective Segmentation approach of Package-to-PCB modeling using Full-Wave EM field Solver

Today's design of high data rate (25 Gbps+) channel calls out modeling of the package to printed circuit board interface using full-wave electromagnetic field solvers. The interaction of the package ball grid array and printed circuit board pad along with via to trace routing leads to an impedance discontinuity, which needs to be modeled given sensitivity of channel performance to reflections at high data rates. There is a need to break the package-to-PCB full model into segments as the use of full-wave electromagnetic field solvers are limited by available computational resources & simulation time. This work explores the package to printed circuit board modeling using full-wave electromagnetic field solver through the segmentation approach. Presented are results on placement of reference planes at different locations in creating segments and then cascading using S-parameters. Results through insertion loss, return loss, crosstalk and time domain reflectometry are shown in comparing the results of the segmentation approach with that of the full model using electromagnetic field solver. This effort is an attempt at presenting a valid approach at placement of reference planes through the segmentation approach using full-wave electromagnetic field solver for high speed package-to-PCB modeling.