EMI Reduction Techniques for Automotive Power Conversion Systems-Slides

Abstract:This presentation addresses the unique challenges of designing power converters to pass automotive EMI/EMC limits. CISPR 25 is the typical starting point for evaluating conducted and radiated emissions in automotive systems. This presentation provides background information on the CISPR 25 standard and explains common noise sources in power converters. Several popular techniques to reduce conducted and radiated emissions are introduced including input filter design, frequency selection, mode selection, snubber design, shielding and layout. Measured results from a 13.5 V input to a 3.3 V, 5 A output converter case study compares the relative effectiveness of several EMI mitigation techniques and present a path to passing CISPR 25 Class 5 conducted emissions. While this talk focuses on automotive applications, the general concepts and techniques are widely applicable.