Coupling Analysis of PCB-Chassis Systems with Signal Lines and Via Structures using SPICE

This paper describes the SPICE modeling of printed circuit boards (PCBs) with signal lines and via structures electrically connected to a metal chassis. First, a PCB model is proposed considering the coupling between signal lines and the power bus due to via structures. Next, the model is expanded to include the chassis and grounding posts. The calculated results using SPICE are shown to be consistent with experimental data. Furthermore, positioning of the grounding posts near the edges of the PCB is shown experimentally and numerically to reduce radiated emissions.