Piezo Electric energy harvester and its interface circuit: Opportunities and challenges

Piezo Electric (PE) harvesters have been of recent interest because they provide a clean and free source of energy. PE is suitable for many applications, especially in wearable healthcare applications where the healthcare device can harvest its needed power, and sense vital signs from the human body. A special interface circuit is needed to extract power from the PE, such as the AC-DC converter. In this paper, we will present a study of the PE harvester and its suitability for low-power applications. Furthermore, a survey of the common interface circuit topologies used in AC-DC converters for PE based systems will be presented. In addition, comparisons between these interface circuits in terms of efficiency, area overhead, and design complexity will be discussed.