Ultra high efficiency of 95% for DC/DC converter - considering theoretical limitation of efficiency

The authors have considered the theoretical limitations in the efficiency of DC/DC power converters used in telecommunication applications. The theoretical limitation of efficiency in a single-stage topology and a two-stage topology is compared. As a result, they have selected a two-stage converter consisting of a buck+half bridge topology. This topology is suitable for high output current and low output voltage DC/DC converters. The prototype using a buck+half bridge topology has been made (3.3 V 60 A). The efficiency of the overall converter was 92% at full load, and an ultra high efficiency of 95% at half load was successfully achieved.