# Simple Voltage boost circuit question.

#### Stewbacca

Joined Jun 30, 2015
2
I have a project that I've been working on for quite a while now. I'm using a scavenged laptop motherboard in a custom computer project, and I would like to provide power from a small form atx power supply which can suppy 12v at up to 17a so around 200w total power available. but it's not enough to power the laptop board. Any commercially available power booster that I've found can't provide the 3.5a required by the motherboard. I've found some variable voltage ones that are overkill, imo, for this. Can anyone help me design a small relatively inexpensive booster that can take the 12v to 19v? I have soldering, wiring, and moderate electronics skill, but I just don't have the maths or design skill to design it. Thanks in advance.

#### AnalogKid

Joined Aug 1, 2013
8,589
AC/DC 19 V power supplies ('laptop battery charger') are on ebay for $6, new, free shipping. How badly do you want to build one? Or, if you want to stay with DC/DC boost:$8 - http://www.ebay.com/itm/DC-DC-Step-Up-Converter-Boost-8-32V-to-9-46V-MAX-15A-150W-Voltage-Regulator-/251405726377?pt=LH_DefaultDomain_0&hash=item3a88f2f2a9
$11 - http://www.ebay.com/itm/12V-to-19V-24V-15V-power-supply-DC-Boost-Power-converter-volt-Voltage-Regulator-/361311825130?pt=LH_DefaultDomain_0&hash=item541fdcecea Designing one from scratch would not be difficult because you have a stable input, a known load, and a ton of chips and app notes to choose from. But is this to be a learning experience, or do you want to throw$6 at it and get on with your life?

ak

I always like to learn new skills, but I need to get going with this project. I think the $8 option will work for now. Mostly I was running into information overload, I kept finding promising info from google, but most of it I didn't understand how to apply my specific boost needs, lacking the knowledge of circuit design, so I thought I'd reach out. Thanks for the link. I was having a heck of a time finding a unit that would provide the amps I needed without costing$30+. Thanks again.