Abstract:
Future wearable devices and other deployed sensor systems, including smart agriculture or environmental monitoring, will require new approaches for long-term powering and operation that avoid individual battery recharging. One approach is the use of thermoelectric energy harvesting, where energy is extracted from thermal gradients using a solid-state thermoelectric generator (TEG). Even centimeter-scale TEGs can provide microwatts of power from small temperature gradients, such as body heat, but they present a number of challenges in terms of low-voltage, highly-efficient energy conversion at the output.
In this talk, I will present recent work in low-voltage energy harvesting applied to wearable devices, including some of our own low-level improvements in DC-DC converters and complete thermoelectric energy harvesting solutions – including true battery-less, wearable bioelectronic sensors powered by body heat. I will also present a number of ultra-low-power (ULP) sensor readout interface circuit approaches that enable ULP (<10µW) read-out for resistive-, voltage-, and current-domain sensors, such as temperature, pH, and electrochemical reactions. Together, thermoelectric energy harvesting combined with ULP sensors and read-out ICs are a promising avenue for powering wearable devices using body-heat energy harvesting.
Bio:
Matthew Johnston received the B.S. degree in electrical engineering from the California Institute of Technology in 2005, and the M.S. and Ph.D. degrees in electrical engineering from Columbia University in 2006 and 2012. He was a Co-Founder and Manager of Research with Helixis, Carlsbad, CA, a Caltech-based spinout developing instrumentation for real-time PCR, from 2007 to its acquisition by Illumina in 2010. From 2012 to 2013, he was a postdoctoral scholar with the Bioelectronic Systems Lab at Columbia University. He also worked as an Associate at a life sciences venture capital firm in New York City.
Dr. Johnston joined Oregon State University in 2014, where he is currently an Associate Professor with the School of Electrical Engineering and Computer Science. His current research interests include the integration of sensors and transducers with silicon CMOS integrated circuits, lab-on-CMOS platforms, ultra-low-power sensor electronics, stretchable circuits and systems, bio-energy harvesting, and low-power distributed sensing.
Dr. Johnston was the recipient of the 2020 Semiconductor Research Corporation (SRC) Young Faculty Award, the 2021 Oregon State University College of Engineering Faculty Teaching Excellence Award, and the 2021 Oregon State University Provost Fellowship. He is currently an Associate Editor of the IEEE Transactions on Circuits and Systems II, and he has also served as an Associate Editor for the IEEE Open Journal of Circuits and Systems and the IEEE Transactions on Biomedical Circuits and Systems.
The webinar is free but registration is required. Zoom link will be sent after registration.
Virtual: https://events.vtools.ieee.org/m/448413