Analysis and Design of a High-Frequency DC/DC Converter Based on a Resonant Rectifier

In high-frequency dc/dc converters, the resonant rectifier is an important stage that guarantees high efficiency and optimal operating characteristics. However, the existing design approaches are based on trial methods and cannot achieve optimal results. A systematic and effective design method for a current-driven class E circuit is proposed in this paper, which consists of the detailed theoretical analysis and numerical derivation. Furthermore, with the optimal design method, the input impedance of the resonant rectifier can maintain quasi-resistive characteristics. Demonstration of this approach is provided through the experimental results of a 20 MHz dc/dc prototype. The system efficiency can be as high as 81.5% based on the optimal design method of the rectifier.