A 1452-% power extraction improvement energy harvesting circuit with simultaneous energy extraction from a piezoelectric transducer and a thermoelectric generator

This paper presents a dual-source energy harvesting circuit that efficiently and simultaneously extracts the energy from a piezoelectric transducer (PZT) and a thermoelectric generator (TEG). The harvester operates in a dual-source pile-up mode (DPM) to efficiently extract the energy from both sources with an increment of the damping force, resulting in a 1452% improvement of power extraction even without a TEG, which is the best among the-state-of-the-art works. Also, the harvester operates in a boost converter mode (BCM) without an additional power switch, achieving 75 % conversion efficiency at 450 μW output power. With a single-shared inductor, a simple control scheme enables the harvester to operate in both DPM and BCM by a time-multiplexing method, consuming low quiescent current of 240 nA.