Convert 5VDC to 3.7VDC?
I'm currently working on a speaker project, and I want it to be powered by 4x 18650 3400mAh 3.7V batteries in parallel, but when they are recharged (with a separated 18650 wall charger), I want to be able to power my speaker from a wall power supply. The idea is to get the 5v power supply voltage down to something between 3.7v and 4.2v, in order to mimic the battery voltage. I already chose this one which is a 10amp-capable power supply in order to be sure to always give the speaker enough current (speaker current consumption is between 0,55 at medium volume and 3 amps a maximum volume). I first thought that i would use this board to convert 5v to 3,7v but it's only able to output 1.25 amps max so I need to figure out a way to convert 5v to 3.7-4.2v without loosing a lot of current. I've heard of low dropout regulator (LDO) but I cannot find one capable of delivering 4amps or more...
Any help is appreciated !