Voltage Inverter Needed

[GreyGnome]

Hello,
I would like to find a small voltage inverter. I have a 19V positive power supply from an old laptop, and I would like to use it to create positive and negative 12v outputs, at 300mA or less current.

I looked on eBay for a module that would do it. There's a lot of cheap modules that can reduce the voltage, but I am having a devil of a time finding an inverter to get the negative side. I could build it myself from something like an LT1945 but since things from China are so cheap I thought I'd be able to pick something up.

Have you heard of something like this? I'd like to budget under $15 for the thing.

Thanks.

 

[(*steve*)]

Here is the sort of thing you can use.

Note that this generates -5V from +5V, but a similar device should be available for 12V. Unfortunately I can't find one on eBay. This particular unit is a switched capacitor design. These are not really suited to high currents, but there are topologies using inductors that are.

It may be possible to build one for $15, but it depends on your skill level and how easy parts are to come by.

 

[GPG]

at 300mA or less current.

Why less?
http://www.linear.com/product/LT8471

 

[GreyGnome]

Here is the sort of thing you can use.

Note that this generates -5V from +5V, but a similar device should be available for 12V. Unfortunately I can't find one on eBay.

Awesome- I just wasn't using the proper magic term. "Converter" seems to be the one. I found this, which is exactly what I was looking for:

http://www.ebay.com/itm/voltage-adj...611372?hash=item3d0200caac:g:BSUAAOSwyQtV4pvb

All for only 10 bucks!

 

[GreyGnome]

Why less?
http://www.linear.com/product/LT8471

Only because I wanted at least 300mA but if that was too much to hope for I didn't want people to skip my post because one can only find those at 100mA, or 150mA, or what have you. I was trying to aim low, and hopefully cast a wider net.

Thanks for the link! ...Double thanks! I just took a glance at the datasheet and that is an awesome chip! It's compelling enough that I just may build my own supply using it. The features and power capabilities mean I'm thinking of building it for a DIY bench supply.