High Conversion Ratio Multiphase Boost Converter With Dynamic Charge Equilibration for Bipolar Outputs

This article proposes a multiphase bipolar-output hybrid (BOH) converter designed to achieve a high conversion ratio, minimal output ripple, and enhanced efficiency. By incorporating a dynamic charge equilibration (DCE) mechanism, the proposed converter reduces parasitic switching losses by 26%. The DCE driver employs LC resonant charge-recycling, effectively reusing stored charge and minimizing switch delay. Furthermore, the DCE replica technique ensures balanced charge distribution, even under challenging load transients. Experimental results demonstrate the superior performance of the multiphase BOH converter, achieving a peak efficiency of 95.7% at V_IN = 4.5 V and 93.2% at V_IN = 3.3 V, while supporting load currents up to 1.5 A. Additionally, the converter exhibits low output ripple, with less than 2 mV for the positive output and 3 mV for the negative output.