Real time clock applications, real time clock power loss, online clock - tatanh1983/conchodom GitHub Wiki
ISL1208 Series 2.7 - 5.5 V 2 Byte Ram I2C® Real Time Clock/Calendar - SOIC-8
https://www.futureelectronics.com/p/semiconductors--real-time-clocks/isl1208ib8z-tk-renesas-5027802