Heterogeneous CMOS-MEMS based Boost Converter for 2.4 GHz RF energy Harvester

Abstract

Internet of Things (IoT) has experienced a significant growth in last few years. Billions of battery-powered wireless sensors are expected to be employed as the IoT becomes an integral part of our daily lives. Therefore, ambient energy resources such as light, RF source, EM radiation, thermal energy can be utilized to prolong the lifetime of batteries for sensors. In this work, ambient RF energy source is used for energy harvesting to power up the wireless sensors and low power electronic devices. For the first time, we experimentally demonstrated RF energy harvester to scavenge 2.45 GHz from Wi-Fi sources using commercially available CMOS-MEMS (micro electromechanical switch) hybrid switches. The use of MEMS switches in the boost converter instead of conventional NMOS switches reduces the leakage current, stabilize the ON-state resistance, and improves the overall efficiency. Our experimental result indicates that the use of MEMS switches increases the efficiency of the energy harvester more than 15% as compared to its NMOS counterpart.