Effects of Interactions Between Filter Parasitics and Power Interconnects on EMI Filter Performance

This paper first analyzes the electrical parameters of differential-mode (DM) and common-mode (CM) propagation on power interconnects. The impedance-transformation effects of the power interconnects are then investigated. The interactions between the parasitic parameters in electromagnetic-interference (EMI) filters and the transformed impedances by the power interconnects are explored in detail. It is found that the interactions can degrade EMI-filter performance at high frequencies. Simulations and experiments are finally carried out to verify the analysis.