An efficient boost converter control for thermoelectric energy harvesting

This paper presents an ultra-low power control circuit for a DC-DC boost converter targeting implantable thermoelectric energy harvesting applications. Efficiency of the input converter is enhanced by utilizing zero-current switching technique. Adaptive delay between ON states of switches assures zero-voltage switching of synchronous rectifier and reduces switching losses. The control circuit employing both techniques consumes an average power of 620nW. This allows the converter to operate from harvested power below 5μW. For voltage conversion ratios above 20, the proposed circuits and techniques demonstrate efficiency improvement compared to the state-of-the-art solutions.