An Ultra-low Power Thermo-Electric Harvester in 45nm CMOS Process

An ultra-low power thermoelectric harvester implemented in 45nm CMOS (Complementary Metal Oxide Semiconductor) process is presented in this paper. With the increasing demand of using low voltage portable devices and wireless systems, energy harvesting has become an attractive approach to overcome the problems correlated with battery life and power source and TEG (Thermoelectric Generator) is the most commonly used among different types of energy scavengers. The input of the system will be coming from a TEG with a minimum input voltage of 100mV and will have an output of 1V (unregulated). The architecture for boosting such extremely low voltages is based on a modified Dickson charge pump using ring oscillator as clock signals. The ring oscillator is designed to operate in the subthreshold region employing a forward body bias design technique.