A Fully Integrated Dual-Phase Switched-Capacitor Rectifier for Piezoelectric Energy Harvesting With High Power Extraction Enhancement

This brief presents a fully integrated dual-phase switched-capacitor (DPSC) rectifier for piezoelectric energy harvesting (PEH). An on-chip reconfigurable switched-capacitor (SC) converter is implemented to eliminate the need for external inductors and capacitors, significantly reducing the overall system volume. The efficiency is enhanced by reusing the inherent capacitance (Cₚ) of the transducer as a flying capacitor of the SC converter through a dual-phase charge transfer technique. Furthermore, an all-digital flipping control scheme is employed to minimize system power consumption. The proposed circuit was fabricated in a 0.18μm BCD process. The measurement results show that a 76% flipping efficiency and a 6.7× energy extraction enhancement are achieved.