An Electromagnetic Energy Harvester and Power Management in 28-nm FDSOI for IoT

This paper presents the design and development of an integrated in-package electromagnetic energy harvester sensor node (EHS) and power management for bicycle applications. An integrated coil inside an IC-package delivers energy of 1-7.5 mJ per wheel rotation at a cycling speed of 8-40 kph with a total load resistance of 1k Ω. Unlike the traditional EHS the power delivery path is separated to provide 1.8 V for the transceiver and sensor modules, and 0.4 V for the on-chip microcontroller (MCU) to enable near/sub-threshold operation. A low-power control unit is designed for the proposed harvester to enable switching between states (sense, process, transmit) in cooperation with MCU. Simulation results and analysis of the proposed electromagnetic EHS in response to a time-varying energy source shows significant improvement in energy availability and scalability of our EHS compared to the state-of-the-art. Achieving higher efficiency at the system level design enables significant reduction of the size of the harvester and require energy store capacitors compared to the prior works.