Analysis of a Low-Pass Filter Employing a 4-Pin Capacitor

Abstract

Capacitors with two or three leads tend to make poor low-pass filters at high frequencies (e.g., >100 MHz) due to the mutual inductance between the input and output sides of the filter. This work proposes a four-lead low-pass filter capacitor design that minimizes the magnetic flux coupling between the input and output. Measurements of a prototype capacitor confirm that it performs significantly better than a typical two-lead capacitor at high frequencies.