Hi,
I am wanting to incorporate a battery monitor circuit into my project and after some considerable reading and research, this is the design I've ended up settling on.
Main Power is the Battery Power Source (8 - 12V) and the 3V3 is what powers the Atmega IC using a 3V3 regulator.
During my research, I looked at several battery monitor designs ranging from basic voltage dividers to circuits controlled by MOSFETS but out of them all, the circuit above seemed to be the best option for my needs - assuming it's correct and will work.
The main criteria for the design is that firstly, the circuit doesn't consume much power and drain the battery and secondly, the main power should not end up anywhere near the Atmega as was the case with some designs I looked at. The design above seems to use clamping diodes to prevent this.
Hopefully, someone can give the circuit the once over to see if there's any mistakes or issues before I commit the design to PCB.
Thanks!!!