Hello to the experts here in the forum. I want to build a portable altimeter with a Pro Mini Arduino, I already have a BMP280 module. Housing with battery compartment I have in prospect, in the compartment fit only 2 AA batteries (Eneloops) so max. 2.6V voltage available. Since this is a bit little, especially for a graphic display (3,3V) , I thought of a step-up converter. Does anyone have experience with this? There are supposed to be better and worse step-up converters.