Energy Harvesting and Integrated Power Conversion for Micro-Scale Sensor Nodes

Sensor nodes are becoming an increasingly vital part of everything we do, and form an important aspect of Internet of Things (IoT), big-data research and, consequently, investment trends. As the number of sensors increases to the order of trillions, their energy consumption, running and maintenance costs will become critical to deploying this technology. The cost of powering these sensor nodes with batteries, or individually wiring them to the mains, greatly diminishes their benefits. Energy harvesting is an alternative that is gaining popularity both in research and industry. The design of energy-efficient integrated sensor systems for wireless sensor nodes has been a research area of immense interest and activity over the last decade. This project focuses on the design of integrated ultra-low power energy harvesting sensor systems, and aims to demonstrate an integrated cm-scale energy-neutral sensor.

As part of this project, a new technique for power management has been demonstrated, which can achieve over 30% additional compute cycles compared to prior reported works. The energy benefits of such systems are easily eroded by inefficient mixed-signal power management circuit blocks. Through novel circuit techniques demonstrated in silicon, this work also delivers best-in-class performance for oscillators and voltage monitors that enable energy-harvesting to be efficiently employed for sensor nodes.