0

Here's the problem: I carry around two devices, but at different power requirements - one at 20V/3.5A and the other at 12V/3.5A. I'd like to only carry around one power brick and just carry an adapter cord.

I've looked around everywhere for universal power supplies, but the only one I found that included both 12V and 20V was at 5A. I don't want to risk damaging my batttery at the higher amps.

So now I'm looking to an engineering solution. I have a basic understanding of electrical engineering, but I'm having a little trouble here figuring out what I'll need.

From my research, I believe I can use a 20V/3.5A power supply and a 12V step down voltage regulator. The problem is I can't find any voltage regulators at the correct amps - either too low at like 600 mA or way to high at 20A. Does anyone know where or how I can find the part I'll need?

I assume, using the pinout diagram, I can essentially just run the power from the 20V power supply thru the voltage regulator and come out with 12V. Am I missing anything?

And if anyone has a better solution, I'm all ears (or eyes).

JYelton
  • 32,302
  • 33
  • 134
  • 249
rphello101
  • 123
  • 5
  • 4
    Read [Choosing power supply, how to get the voltage and current ratings?](http://electronics.stackexchange.com/questions/34745/choosing-power-supply-how-to-get-the-voltage-and-current-ratings). If the device only draws 3.5 A, having a higher-rated power supply won't force it to draw more. – The Photon Aug 27 '14 at 18:38

1 Answers1

3

The 12 V 5 A, and 20 V 5 A supply will be fine. A higher current rating is OK. For more details see https://electronics.stackexchange.com/a/34746/4512

Community
  • 1
Olin Lathrop
  • 310,974
  • 36
  • 428
  • 915
  • Thanks for the response. This means I can buy one I found, tho I'd still be interested in how to build what I need. – rphello101 Aug 27 '14 at 22:41