A 93.2%-Efficiency Multi-Input Bipolar Energy Harvester With 17.9× MPPT Loss Reduction

The proposed multi-input bipolar energy harvester (MIBEH) can harvest different input sources by using the source battery rotating supply (SBRS) technique, and can achieve low-input source voltage ripple and bidirectional energy harvesting with the negative source enhanced supply (NSES) technology. Moreover, to improve harvesting efficiency, the proposed double transconductance reduction (DGR) comparator is designed with different bias currents according to different input powers. Furthermore, the proposed body-driven zero-current detector (ZCD) can achieve both high precision and low-power consumption. The end-to-end peak efficiency is 93.2%, and the output power ranges from
$1~\mu \text{W}$
to 80 mW.