Sparkfun is selling an interesting RTC clock chip board. It draws 22 nA. It has a rather novel clock generator... a tuning fork crystal disciplines an RC oscillator every few minutes. They claim 3 minutes per year drift.
https://www.sparkfun.com/products/14642 _______________________________________________ time-nuts mailing list -- email@example.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.