A Self-Powered P-SSHI Active Rectifier With Energy-Efficient Adaptive Switch Control for Piezoelectric Energy Harvesting

This paper presents a self-powered parallel synchronized switch harvesting on inductor (P-SSHI) active rectifier with an energy-efficient adaptive switch control circuit. The energy-efficient adaptive switch control circuit reuses comparators within the active rectifier for both zero-crossing detection and voltage flipping detection, simplifying the switch control module. The proposed active rectifier incorporates an active diode and a MOSFET within each energy transfer path to mitigate the forward voltage drop across rectifying elements. The proposed P-SSHI circuit which includes a diode in each voltage flipping path shows high adaptability to different inductances. All the auxiliary circuits are powered by the storage capacitor. The proposed circuit is designed in 180 nm CMOS process, and the total occupied chip area is 0.18 mm(2). The power dissipation of the switch control module is only 0.15 mu W, owing to its simplicity. The simulation results show that the proposed design achieves a high voltage flipping efficiency of 85.4%. The maximum output power is 5.5 times greater than that of the ideal full-bridge rectifier.