Need +12vdc to dual +/- 22vdc

Hi, everyone!

I'm an electronics hobbiest, but design is beyond my capabilities.

I've searched here, but I guess I'm not very good at using the search function, as I got so many hits for "dual output power supply" that I gave up reading!

I have a device that I want to install inside my computer case; it requires both a +22vdc @ 600ma and a -22vdc @ 600ma.

Since all computers have a molex connector with a handy +5vdc and +12vdc @ 5A+ is there a simple step up converter someone can point me at? The less componenets the better! lol

Thanks in advance for reading this post.

It's possible but it certainly isn't easy.

Does it really need to be 22V?

You can buy 12V to 24V converter modules pre-built.

National, Maxim Semiconductor and Linear Technology all sell ICs which will make building this easy - see their websites (use Google) for more information.

Just stick a mains power supply in the computer case, easiest way!.

Not being a wiz at electronics, I can't say for sure that it must only be 22vdc, but the circuit board is labeled as +12, +5v,GND,-12v,+3v,+22v,GND,-22v. Also, I'm told that the max output of the power supply is 600ma with a peak of 800ma.

The reason why I want to use a step-up circuit for either the 12v or 5v rail is because I'm using the ATX supply for the other 4 voltages (+12/-12/+5/+3).

I'm not sure what would happen if I used an ac to 22vdc adapter -- I'm so afraid that I may short something out.

From what I am able to determine from following the +/-22vdc line is that it powers an LED module (it's a scrolling 7 segment unit with 8 characters).

If it is safe to use an external ac adapter, where can I get one that outputs both -22vdc and +22vdc? Or is there a small circuit to build/purchase that will take a postive voltage and convert it to both -/+ output?

If it is not safe to use an external adapter based on my description, what would happen if I used a step-up +/-24vdc voltage?

Thanks, you guys are so knowledgable and kind to help out!

Additional research tells me the +/-22vdc is used for the flash memory, so I guess it has to be that value.

Digikey sells DC/DC converters easy to use too.

I couldn't see any at DigiKey that took 12vdc to 22vdc. But I admit that when it comes to searches, I'm inept.

Do you have a link to these modules at DigiKey?

Here's how to get a dual power supply from a transformer.

There need to be a couple of modifications: use a 24V transformer and >1500µF 50V capacitors.

This will give +/-33VDC, you'll need to add an LM317 and LM337 to get +/-22V.
**broken link removed**
For 22V:
R1 = 120R
R2 = 2k

Thanks, Hero999 !

You rock. But you need to change your name to HERO#1.