Development of simple solar charge controller using 8-bit microcontroller attiny85 A.R. Wing Wira, Ananta Rezky, Andrew Bastian, Kresna Devara, Arief Udhiarto and Tomy Abuzairi E3S Web Conf., 67 (2018) 01018 Published online: 26 November 2018 DOI: 10.1051/e3sconf/20186701018