Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Low voltage dual supply from old computer PSU
Low voltage dual supply from old computer PSU
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 6th December 2009, 05:34 PM   #1
chingyg is offline chingyg  South Africa
diyAudio Member
Join Date: Sep 2009
Location: South Africa
Default Low voltage dual supply from old computer PSU

Hey guys

I think the power supply must be the hardest part in building an amplifier, power transformers are expensive and hard to come by, however old computer psu are readily available.

The highest voltage we can obtain from a ATX PSU is +-12V, which translate to about 36W into a 8 ohm load with bridging. the +12V line can source at least 10A, however the -12V can't even sink more than 1A.

What I've doing is that, I'd open the power supply and trace the -12V all the way back to the power transformer, then I would connect a pair of high current ultrafast diode (cathode to the two transformer output, anode gets connected together) to the 2 output of the transformer. after that you'll need to connect an inductor to the common anode of the rectifiers (I use the inductor on the 5V line from another ATX PSU), then you can use it as your new -12V line, it should be able to sink as much current as your rectifiers can substain.

To go a step further, most ATX PSU have trimmers on them where u can adjust the output voltage to about 14V (after than the over voltage protection trips, it can be disabled however, but then you need to replace the capacitors on the output stage if you don't want them to blow up, I've seen people modified them to +-24V power supplies)

Okay, that's just a little bit of my experience that I would like to share with you guys, I thought it might help.
  Reply With Quote


Low voltage dual supply from old computer PSUHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Dual supply for LM1875 split supply dovganj Power Supplies 30 6th November 2009 04:19 AM
Dual soundcards or RCA to computer speakers rick57 Digital Source 0 29th December 2004 09:56 AM
Low voltage noise dual OP Holger Barske Parts 7 24th May 2004 07:57 AM
dual voltage SuperRegulator? hegestratos Solid State 22 17th May 2004 04:05 PM
high-voltage regulated dual power supply zzz Solid State 1 17th September 2002 02:15 AM

New To Site? Need Help?

All times are GMT. The time now is 01:05 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio