EMI noise reduction between planes due to a signal via with a ground via at various distances

Abstract

This study investigates the behavior of EMI noise reduction through a simple 2-layered printed circuit board cavity, as a ground (GND) via is placed in proximity of a signal (SIG) via. Provided that the maximum frequency of the signal's harmonic content is known, an algorithm which predicts the maximum distance at which the GND via placement will effectively provide noise reduction has been developed. This could be used as a design guideline for PCB designers.