I know the common recommendations about batteries. "Keep motors & chips seperate"... The project I'm working on needs reliable power on both, and I would prefer if I can use a single battery (bank possibly). I'm looking into giving microcontroller brains to my full sized boat. The engine has a battery charging circuit for a 12v battery. Since I have a nice source of charging power, I would like to use that for the microcontroller circuits.
I will be using a SLA battery for main power to start the engine, and steer the boat. Should I use a seperate small battery for the microcontroller, and have the main battery keep it charged? Or can I just use a voltage regulator for the small electronics?