Sub-30-mV-Supply, Fully Integrated Ring Oscillator Consisting of Recursive Stacking Body-Bias Inverters for Extremely Low-Voltage Energy Harvesting. - Hikaru Sebe; Tomohisa Okumura; Shintaro Sumi; Daisuke Kanemoto; Po-Hung Chen; Tetsuya Hirose (ESSCIRC, 2023)