Title :
A micropower energy harvesting circuit with piezoelectric transformer-based ultra-low voltage start-up
Author :
Aldo Romani;Antonio Camarda;Alessio Baldazzi;Marco Tartagni
Author_Institution :
Department of Electrical, Electronic, and Information Engineering “
fDate :
7/1/2015 12:00:00 AM
Abstract :
This paper introduces the use of piezoelectric transformers (PTs) as key elements for ultra-low voltage start-up circuits for battery-less energy harvesting applications. Firstly, a step-up oscillator topology based on a PT and a JFET is presented. The circuit is able to start from voltages as low as 16 mV, and to boost the output voltage up to 1.32 V in a no load condition. In order to validate the proposed approach, a surrounding power management and conversion circuit is developed. This circuit is able to automatically enable a boost DC/DC converter once the start-up circuit has generated a sufficient voltage. The whole circuit self-starts with an input voltage of 30 mV, and the maximum conversion efficiency referred to the maximum power point (MPP) is higher than 40%, with an intrinsic current consumption as low as 1.3 μA.
Keywords :
"Oscillators","Threshold voltage","JFETs","MOSFET","Inductors","Monitoring","Capacitance"
Conference_Titel :
Low Power Electronics and Design (ISLPED), 2015 IEEE/ACM International Symposium on
DOI :
10.1109/ISLPED.2015.7273527