Modeling and Simulation of Ferrite and Varistor EMI Suppressors

Abstract

In this paper, modeling and simulation of electrical characteristics of EMI suppressors will be presented. Ferrite and varistor EMI suppressors consist of conductive layers embedded in ferrite or varistor monolithic structure, which make them very suitable for elimination of conducted EMI. In this paper software tool for calculation of electrical characteristics of ferrite and varistor EMI suppressor is given. A scalable analytical model of different EMI suppressor structures suitable for design and circuit simulations is presented. By using our algorithm, we are able to predict correctly all variations of electrical characteristics introduced by varying geometry parameters of EMI suppressor. These integrated passive devices were tested in the frequency range 1MHz-3GHz using an Agilent 4287A RF LCR meter. The measurements confirm the validity of the analytical model