I've made and standalone Arduino uno to interface with a Nokia 5110 display. I'm powering the circuit with a lipo battery directly, I have 3,85v now, but if I charge it, I will have 4,2v +/-
The maximum voltage for the display it is 3.3v, so it will be risky having 4,2v.
which is the best way to regulate the power to 3.3v with a Lipo? I'm thinking in a zener diode, what do you think? (the lm 1117 for example needs an input of at least 4,5v)