Power Management for Vibrational Energy Harvesters

As known, wireless sensing applications can be enabled by using ultra-low-power electronics for sensing, processing and transmitting information, in order to extend the battery lifetime. Battery size is also a limiting factor constrained by the application requirements. In this scenario, energy harvesting is a fascinating solution, which can attenuate the trade-off between battery size, power consumption of the load circuits and battery lifetime. In some particular applications, characterized by long times in which no energy is available in any form, the battery could completely deplete because of the standby current of the load circuits. For that reason, battery-less applications become more and more relevant. In this paper the available circuit techniques for interfacing vibrational energy harvesters are presented and compared.