CNFET-Based 0.1- to 1.2-V DC/DC Boost Converter With Voltage Regulation for Energy Harvesting Applications

With the wide-scale adoption of various low-voltage power hungry wearable and portable electronic devices, researchers are compelled to focus on alternate sources of energy. This problem further demands attention as advancements in battery technology have failed to match the growth in power consumption of such devices. Energy harvesting has been widely debated and studied as an alternative of batteries in such devices. Adoption of such techniques requires an efficient dc/dc step-up conversion to boost ultralow-voltages scavenged from the environment. This paper presents a carbon nanotubes-FETs-based architecture for harvesting ambient energy from the surroundings (typical voltage ~100 mV) and boosting it to useful voltage levels (1.2 V). Such a converter is capable of sourcing sufficient current (120μA) to supply modern low-power CMOS devices and exhibits an efficiency of 27%. In addition, a voltage regulation circuit is also proposed to minimize the fluctuations in output due to unreliable supply of input voltage. The design is modeled using extensive simulations in experimentally verified Stanford CNFET model that has been calibrated for 90% accuracy. This paper concludes the discussion with a comparison between the proposed architecture and other CMOS-based designs.