I am new to power supply issues and need some advice. I have dealt with a linear regulator and that is fine, but wastes a lot of power. I am looking into a switching power circuit as they are way more efficient. To step it up another notch I also want to be able to use two different levels of input voltage.
I need a 3.3V power supply and would like to run the system on some 3.6 lithium cells I have and a 9V batter when we get in a pinch. Turns out there is a ton of information out there and having trouble narrowing it down. Anyone have a schematic laying around?