Abstract

UCC33xx0-Q1 is a family of integrated isolated bias (IIB), DC/DC modules operating at 64MHz, switching frequency. Due to its high frequency, aiming low EMI can be a challenge if the appropriate layout and EMI components are not utilized. This app note is intended to explain how to pass CISPR25, class 5 for UCC33xx0-Q1 family. Guidelines for proper setup, EMI filter component selection and PCB layout to meet the CISPR 25 standard and achieve low emissions for both Conducted Emissions (CE) and Radiated Emissions (RE) are presented. Passing the limits of CISPR25 are required for automotive applications such as traction inverters, HEV/EV charging, Battery Management Systems (BMS) and on-board chargers (OBC). The target audience is field applications, systems and application engineers as well as any engineer interested in EMI for DC/DC converters.