Tong, TaoZhang, XuanKim, WonyoungBrooks, DavidWei, Gu-Yeon2016-02-242016-02-24Tong, Tao, Xuan Zhang, Wonyoung Kim, Brooks, D., and Gu-Yeon Wei. 2013. "A fully integrated battery-connected switched-capacitor 4:1 voltage regulator with 70% peak efficiency using bottom-plate charge recycling," In the Proceedings of Custom Integrated Circuits Conference (CICC13), San Jose, CA, September 22-25, 2013. doi:10.1109/CICC.2013.6658485http://nrs.harvard.edu/urn-3:HUL.InstRepos:25607235This work presents a switched-capacitor (SC) DC-DC voltage regulator that converts a 3.7V battery voltage down to ~0.8V in order to power the `brain' SoC of a flapping-wing microrobotic bee. A cascade of two 2:1 SC converters offers high efficiency for a 4:1 conversion ratio. A charge recycling technique reduces the flying capacitor's bottom-plate parasitic loss by 50% and overall conversion efficiency reaches 70%. The output droop is less than 10% of the nominal output voltage for a worst-case 47mA load step.en-USConference Paper2016-02-2410.1109/CICC.2013.6658485