A Synchronized Multiple Bias-Flip Interface Circuit for Piezoelectric Energy Harvesting Using Optimized Switched-Capacitor Arrays

This paper introduces a new implementation of the synchronized multiple bias-flip (SMBF) interface circuit for piezoelectric energy harvesting systems. The proposed circuit uses an optimized and easy-to-drive capacitor array for multiple voltage bias-flip actions. The switched-capacitor array consists of five capacitors. It is able to carry out 27 continuous voltage bias-flip actions by re-organizing the multiple capacitors and properly reusing them in different phases. The proposed circuit topology extracts more power than the previously proposed harvesting circuit, which again validates the optimal SMBF theorem. It also explores the potential and reveals the limitations of piezoelectric energy harvesting improvement by using multiple bias-flip actions.