A vibration-based electromagnetic energy harvester system with highly efficient interface electronics

This paper presents a vibration-based electromagnetic (EM) energy harvester system utilizing novel and highly efficient interface electronics. The energy harvesting module up-converts the environmental low frequency vibrations for increased AC power output. The interface circuit employs a boot-strap technique to reduce the threshold voltage of the rectifiers further increasing the power conversion efficiency of the overall system. The complete system, composed of an energy harvester module, and a compact 0.35 µm CMOS IC, was fully validated. It is capable of powering a 1.5V, 15µA load with 65% conversion efficiency, and 5% ripple, at an external vibration frequency of 10Hz. The recorded efficiency is the highest achieved value for vibration-based EM energy harvesters with passive rectification to the best of our knowledge.