Abstract

UCC33xxx-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 CISPR32, class B for UCC33xxx-Q1 family. Guidelines for proper setup, EMI filter component selection and PCB layout to meet the CISPR 32 standard and achieve low emissions for both Conducted Emissions (CE) and Radiated Emissions (RE) are presented. Passing the limits of CISPR32 are required for industrial applications such as PLC I/O modules, medical equipment, energy storage systems, industrial and telecom power distribution boards. The target audience is field applications, systems and application engineers as well as any engineer interested in EMI for DC/DC converters.