Apr 072016

Well, I’ve been researching the problem. I have a battery that could be floating anywhere from 10V to 14.6V, depending on the input from the charger.

I have a computer PSU, that is not happy with voltages outside of 10.5V—13.5V.

What are my options?

  • Linear regulator: the standard ones have a 1.5V drop across them, which at the full rated input current of the PSU, 8A is 12W. Per node.
  • Low drop-out regulators get a little lower, but I’d still lose a few watts per node.
  • Buck converters can do better, but a lot still need at least 1V difference.

So I really need to boost it first, then regulate down. One thing I was not looking forward to, was designing then winding the transformer/inductor needed. An off-the-shelf solution therefore seems attractive, even if I miss out on kudos points for a DIY solution.

Redarc make a couple, and this unit looks like it’ll do exactly what is needed. Not cheap, but it seems comparable to what I’ve seen elsewhere. I’ll have a look and see what else there is, but this might be the most time-economical way to solve the problem and the efficiency is pretty good.