Characterization of Ground Bounce and Conducted Emissions of Integrated Isolated DC-DC Converter

Isolation is used in automotive industry for safety reasons to galvanically isolate different domains. Isolated DC-DC converters are used to provide power across the isolation boundary. Integrated isolated power converters provide simpler, smaller, and more robust solutions compared to discrete solutions such as push-pull converters. Integrated isolated DC-DC converters operate at switching frequencies in the range of tens of MHz which makes them potential sources of electromagnetic emissions. Ground bounce is the main cause of the electromagnetic emissions. A 5V-to-5V integrated isolated DC-DC converter based on ISOW774x with interlayer stitching capacitance is developed on a printed circuit board. The ground bounce is characterized by time-domain measurements. The conducted emissions of the converter are measured according to CISPR25 standard. EMI filtering design for the converter is discussed.