Comparison of Top-Plate and Bottom-Plate Charge Reusing in Switched-Capacitor Power Converters

Charge reusing reduces the dynamic losses in switched-capacitor power converters by equalizing the voltages across parasitic capacitances during the dead times between the main charge-transfer phases. In this paper we propose a theoretical model to investigate different charge reusing methods. Boost converters in 65-nm CMOS technology without equalization, with top-plate equalization and with bottom-plate equalization are compared. The simulations highlight the benefits of charge reusing as well as verify the proposed model.