An Efficient Piezoelectric Energy Harvesting Interface Circuit Using A Bias-Flip Rectifier And Shared Inductor

A bias-flip rectifier that can improve the power extraction capability from piezoelectric harvesters over conventional full-bridge rectifiers by 4.2× is implemented in a 0.35µm CMOS process. An efficient control circuit to regulate the output voltage of the rectifier and recharge a storage capacitor is presented. The inductor used within the bias-flip rectifier is shared efficiently with switching DC-DC converters reducing the overall component count.