An ultra-low-voltage-startup circuit for thermal energy harvesting application

An ultra-low voltage startup circuit for power management integrated circuits (PMICs) in thermal energy harvesting applications is presented in this paper. The proposed starter has two stages: LC-tank oscillator and charge pump. Charge pump is a combination of conventional Dickson architecture and charge transfer switches (CTS's). This combination enhances the performance of ultra-low voltage starter. The proposed startup circuit is designed using 0.18-um CMOS technology offering an output voltage of 639 mV from an ultra-low input voltage of 100 mV and a load current of 10 uA.