Embedded Tutorial


Tiny Light-Harvesting Photovoltaic Charger–Supplies

Gabriel A. Rincón-Mora
Georgia Tech

Wednesday, July 26, 12:30~15:30


A fundamental challenge wireless microsystems face is size, and in consequence, lifetime because tiny batteries exhaust quickly. Although small fuel cells and atomic sources store more energy than lithium-ion batteries and super capacitors, they source less power, so they cannot power as many functions. Small batteries and capacitors, however, cannot sustain life for long. Thankfully, the environment holds vast amounts of energy. And of typical sources like light, motion, temperature, and radiation, sunlight produces the highest power density, but only when available. Combining photovoltaic (PV) cells with tiny batteries or capacitors can therefore be more compact, reliable, and longer lasting than any one of these technologies alone. Managing a hybrid system of this sort to supply a milliwatt application, however, requires an intelligent, low-loss charger–supply system. This talk surveys and describes how smart PV-sourced microsystems can draw power from tiny PV cells and supplementary power from small batteries to supply a load and replenish the battery with excess PV power. To that end, the material reviews and discusses miniaturized PV cells, power-efficient charger–supply circuits, and reliable feedback controllers. The presentation ends with measurement results from a prototyped example.


Gabriel A. Rincón-Mora worked for Texas Instruments in 1994-2003, was an Adjunct Professor at Georgia Tech in 1999-2001, and has been a Professor at Georgia Tech since 2001 and a Visiting Professor at National Cheng Kung University in Taiwan since 2011. He is a Fellow of the IEEE and a Fellow of the IET, and his scholarly products include 9 books, 4 book chapters, 38 patents issued, over 170 publications, over 26 commercial power-chip designs, and over 110 invited talks. Awards include the National Hispanic in Technology Award from the Society of Professional Hispanic Engineers, the Charles E. Perry Visionary Award from Florida International University, a Commendation Certificate from the Lieutenant Governor of California, the IEEE Service Award from IEEE CASS, the Orgullo Hispano and the Hispanic Heritage awards from Robins Air Force Base, and two "Thank a Teacher" certificates from Georgia Tech. Georgia Tech inducted him into the Council of Outstanding Young Engineering Alumni in 2000 and Hispanic Business magazine named him one of "The 100 Most Influential Hispanics" in 2000. He has served as Distinguished Lecturer, General Chair, Technical Program Chair, Associate Editor, Guest Editor and Co-Editor, and Chapter Chair and Vice-Chair on multiple occasions for IEEE, several international conferences, and several journal publications.