Design Considerations of Common Mode and Differential Mode EMI Input Filter Based on Planar Ferrite Core

Abstract

The paper describes the design of PCB winding and planar ferrite core based common mode and differential mode EMI filters. The paper proposes idea how to integrate both inductors into single core thus potentially reducing the size of the filter. The inductance and impedance measurements have been shown in the paper. It is discussed possibility to integrate capacitance into PCB based inductor. It has been concluded that integration of input EMI filter has a good potential, especially if the converter works at higher switching frequencies and therefore low value inductances and capacitances are needed. Experimental designs of such passive components are shown in the paper.