Predicting the conducted emissions of switched-mode power converters including component and printed circuit board parasitics

In this paper, a general approach to predicting the conducted emissions of switched-mode power converters is presented. The approach is based on a SPICE time-domain simulation. In order to generate the models used in the simulation and postprocessing, CAD printed circuit board layout data, datasheet information of discrete elements, measurement data of discrete elements and measurement data of the measurement setup are used. Since both discrete element parasitics and printed circuit board parasitics are included, the resulting models can be used to analyze the influence of these parasitics on voltage waveforms and emission spectra. Printed circuit board parasitics are extracted using partial element equivalent circuit method based simulations.