05-02-2016, 12:18 PM
(05-02-2016, 11:47 AM)rahlquist Wrote: What you may want to do is find a stabilized supply that outputs more than 5v (say 9v) stable and the use a normal adjustable DC-DC converter for the final tweak
But that's what a stabilized step-down converter is for. And the additional 3.7V battery is for situations when the PMU decides that 5V DC-IN is insufficient (need not be that large since it's only about buffering temporary voltage drops).
That's the nice thing when you use a SoC that is accompanied by a PMU with battery support. The PMU switches between different power sources on demand. That's why something like a Banana Pi or a Pine64 is superiour as car computer compared to something like a Raspberry or an Orange Pi since the former come with AXP209 or AXP803 and battery support. And that's all that's needed.