A Study of Non-Isolated Resonant Step-Down Converter with Peak Charge Control for High Power Density

Non-isolated resonant converter with peak charge control for high power density is studied in this paper. Step-down converter is required for system on chip (SoC) operation. Buck converter is mainly used, and many studies have been conducted to improve power density by reducing the size of converter. Increasing the switching frequency of converter can contribute to the size reduction. Therefore, class D/E resonant converter suitable for high-frequency operation due to zero voltage switching (ZVS) is chosen as a step-down converter instead of conventional hard switching buck converter. Furthermore, the output capacitor ripple current-based peak charge control and adaptive voltage position (AVP) are simultaneously applied to the class D/E resonant converter. Based on this control method, the size of passive components can be further minimized. The operation of converter with peak charge control and AVP is shown by simulation. Finally, comparison of passive component values according to topology and control method is provided.