A Switched Capacitor Multiple Input Single Output Energy Harvester (Solar + Piezo) Achieving 74.6% Efficiency With Simultaneous MPPT. - Abhishekh Devaraj; Mohamed Megahed; Yutao Liu; Ashwin Ramachandran; Tejasvi Anand (IEEE Trans. Circuits Syst. I Regul. Pap., 2019)