Ultralow Voltage Nanoelectronics Powered Directly, and Solely, From a Tree

Abstract

Complex patterns of electrical potential differences exist across the structure of a tree. We have characterized these voltages, and measured values ranging from a few millivolts to a few hundred millivolts for Bigleaf maple trees. These potential differences provide a unique opportunity to power nanoelectronic circuits directly from a tree. We have designed, constructed, and successfully tested two ICs, powered solely through a connection to Bigleaf maple trees. The first circuit, built in a 130-nm technology, creates a stable 1.1 V supply from input voltages as low as 20 mV, and can be deployed to generate a usable voltage level for standard circuits. The second circuit, fabricated in 90-nm technology is a timer, operating at 0.045 Hz and can be used for time keeping in stand-alone sensor network nodes. The boost circuit and timer consume 10 and 2.5 nW of power during operation, respectively.