A 50 mV Fully-Integrated Self-Startup Circuit for Thermal Energy Harvesting

摘要

A fully-integrated self-startup circuit with ultra-low voltage for thermal energy harvesting is presented in this paper. The converter is composed of an enhanced swing LC oscillator and a charge pump with decreased equivalent input capacitance. The LC oscillator has ultra-low input voltage and high output voltage swing, and the charge pump has a fast charging speed and small equivalent input capacitance. This circuit is designed with 0.18 mu m standard CMOS process. The simulation results show that the output voltage is in the range of 0.14V and 2.97V when the input voltage is changed from 50mV to 150 mV. The output voltage could reach 2.87V at the input voltage of 150mV and the load of 1M Omega. The maximum efficiency is in the range of 10.0% and 14.8% when the input voltage is changed from 0.2V to 0.4 V. The circuit is suitable for thermoelectric energy harvesting to start with ultra-low input voltage.