Ultra low power self-adaptive Solar Energy Harvesting System for WSN Nodes

In this paper, we have proposed an ultralow power self-adaptive solar energy harvesting system to power WSN nodes. An ultralow power non overlapping clock generator has been designed using dynamic threshold MOSFET technique for efficient maximum power point tracking. A power efficient regulation circuit has been designed using strong arm latch to self-regulate the load voltage at a desired value. Regulation circuit eliminates the need of linear regulator for regulation of load supply in final stage of power management unit. This increases the overall system efficiency significantly. The total number of components has also been reduced significantly and hence reducing the overall area. The circuit has been simulated with LTSpice in $0.18 \mu \mathrm{m}$ CMOS technology using TSMC model.