An Efficient CMOS Dual Switch Rectifier for Piezoelectric Energy-Harvesting Circuits

In this research work, we investigated a dual switch (DS) active rectifier for the piezoelectric (PE) energy scavenging system. In the proposed DS active rectifier configuration, two extra switches are shunted across the PE transducer which helps the PE transducer's capacitor in charging and discharging which results in maximum power extraction from the PE transducer. Moreover, in the proposed rectifier configuration comparator controlled active diodes are used instead of conventional/passive diodes to minimize the threshold voltage <mml:semantics>VTH</mml:semantics> drop. The proposed DS active rectifier design is fabricated in a 1-poly 6-metal 180-nm standard CMOS process. The simulation and measured results of the proposed DS active rectifier design have the better power conversion efficiency (PCE) of 91.5 %, which definitely helps in extracting more power than the conventional full bridge rectifier (FBR).