Computer P.S. schematics

Discussion in 'General Electronics Chat' started by seecumulus, Aug 25, 2011.

  1. seecumulus

    Thread Starter Member

    Jul 13, 2011
    Hello -

    I am familiar with the Upgrading and Repairing PC's book, however,
    I cannot locate mine and don't have one presently.

    Do you know where I can find a Type ATX Personal Computer Power
    Supply (+3.3 v, + 5v , +12v, -12v, +5v sb) Schematic - general reference - on the world wide web ?
    A general schematic would be fine - I don't think I need the actual one -
    well at least not yet !

    Thank You
  2. iONic

    AAC Fanatic!

    Nov 16, 2007

    Yes, I know where you can find one. On the World Wide Web! What would we do without search engines.

    "atx power supply schematic"
  3. tom66

    Senior Member

    May 9, 2009
  4. seecumulus

    Thread Starter Member

    Jul 13, 2011
    Yes - This is one that I have printed from my Google Search like
    previous gentleman suggested.
    This one that you linked looks similiar to what I am working on.
    I'll know more of the circuit board tomorrow, hopefully !
    Thank you:)
  5. SgtWookie


    Jul 17, 2007
    The best thing to do is to first determine what controller ICs are used in the supply, and then find their datasheets and application notes.

    Most of them use a fairly similar design. In the older ATX specification, many just had the +5v rail regulated; they needed a load of at least a couple of Amperes in order to regulate the other voltages correctly.

    You'll frequently find that those supplies that have a -5v and -12v simply used 7905 and 7912 fixed negative linear regulators, as the current requirements for those voltages is generally quite low, and only used for RS-232 communication ports.

    For general switching supply information, you might find this site to be a handy reference: