An Always Dual-Path Hybrid DC-DC Converter with Multiphase Interleaving Switched-Capacitor Cell Obtaining 45% Output Ripple Reduction

Switched-capacitor-inductor dual-path hybrid DC-DC converter can achieve high power density and efficiency, with reduced inductor voltage and current stresses and thus reduced inductor conduction loss and volume. However, it suffers from a large output ripple due to the hard-charging of the switched-capacitor (SC). To take advantage of recent in-substrate or on-chip high-density capacitor technologies, this paper proposes a multiphase interleaving operation for the dual-path SC hybrid converter, increasing the equivalent switching frequency and reducing the amplitude of the current ripple. It achieves a significant output ripple reduction within negligible efficiency degradation. The analysis and simulation results prove that the proposed scheme is a better method for reducing output ripple than increasing operating frequency or reducing power transistor size in the hard-charging path.