9v 10 amp regulated output from atx supply

Discussion in 'General Electronics Chat' started by kschax, Oct 8, 2012.

  1. kschax

    Thread Starter New Member

    Oct 8, 2012
    Hi, I am familiar with hacking a 3.3, 5 and 12 v bench supply from an atx supply, but what is the simplest ( money is important, but ease, more so) way to get at least a 10 amp, 9v regulated output?
    Have searched this forum as well as the net, i did find one 3-15 v 18 amp hack, but that required modding the innards at ic level, which i am reluctant to do.
  2. Dodgydave

    Distinguished Member

    Jun 22, 2012
    I modified mine to variable, they are easy to do, its only altering a resistor to vary the feedback,
    look at my videos,

    open up the atx and look what IC markings are, ( ie KA7500, LM339, AT2005,) i will see if you can modify it.
    luvv and gerty like this.
  3. luvv


    May 26, 2011

    Nice mod,you should make a completed projects thread for this.

  4. damien83

    New Member

    Sep 17, 2015
    Hey there

    I joined this forum especially so I could get in contact with you as you seem to be familiar with the at2005b chip which is in my power supply

    I would like to perform the same mod as you guys to make my power supply variable.
    I have managed to track down a pinout for the at2005b which I will attach.
    Just wondering what I need to do please to make this one variable?
    Any help would be appreciated =)
  5. Dodgydave

    Distinguished Member

    Jun 22, 2012
    Hi there,you just hijacked an old thread!! yes i have modified the at2005 chip,

    Hi here is a diagram how i used to modify the atx to variable, you need to fool the ic to think the sense pins 3,4,5, are ok,
    also pin 6 is the over current sense pin, no more than 0.7V or it will shut down,

    the variable voltage is on pin 2 you need to isolate it and connect it to your variable pot, which is across the 12v yellows and blacks,
    connect the Green wire to any black to make the psu run

    IF it works ok,
    the output capacitors on the 12v and 5v supply will need to be increased to 35V working or higher as the output will go upto 28v dc on the 12v rail, and the 5 v rail will go upto 12v

    Note the videos on youtube no longer work...[​IMG]
    Last edited: Sep 17, 2015