Instructables

Convert an ATX Computer Power Supply into a Bench Top Power Supply

I have a few 12 V motors and other sensors/electronics that require anywhere from 3-12 Volts. I usually use a battery pack but did not want to continue to go through batteries. For prototyping, I decided to convert an old ATX power supply into table top power supply. This generally will allow you to have terminals for +12V, +5V, +3.3V and potentially a -5V and -12V. These voltages are pretty common for anyone who works with micro-controllers and sensors.

This project uses:
-Project Box
-x2 mounted LEDs
-ATX Power supply
-Various heat shrink sizes
-Toggle Switch
-x2 5 watt resistors
-x2 330 ohm resistors
 
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Step 1: Preparing an old ATX power supply

Picture of Preparing an old ATX power supply
There are a bunch of references for building them. First thing I did was find a supply laying around I could use. You can reference the diagram below for the color coding of the ATX supplies.

ATX supplies can put out a good amount of current. If the maximum amount of current were to be pulled I recommend using all the wires at  a given voltage to withstand max current draw. It may be 12 ground wires and 4 +3.3V wires etc...

**WARNING!!!! BEFORE CUTTING WIRES, USE A MULTIMETER TO CHECK THE CAPACITORS TO ENSURE THEY ARE NOT STORING ANY ENERGY. IT WOULD ALSO BE  A RECOMMENDATION TO LET THE SUPPLY SIT FOR SEVERAL DAYS FOR ANY CHARGE TO DISSIPATE"

Remove the cover and cut the adapters off of the wires coming from the supply. You should be left with a large amount of wires that will need to be stripped. 
billbillt8 months ago
Great Job!!... I am glad this was presented again... I have made dozens of these over the last ten years... There are still some people on earth that will not believe it is possible for this to work... These make a very powerful and trouble free power supply..
andrea biffi9 months ago
Nice blog! :-)
about power supply I always would warn about using a lethal power of 400 watt or more for hobby purpose...
Lethal power??.. WE are talking about maximum of 12 VDC here... Not lethal... The wattage has nothing to do with it being lethal... It is voltage at amps that kills..
davehartles699 months ago
Do you have entered any pictures of your actual wiring?
Grunambulax9 months ago
Good idea well executed.
petercd9 months ago
I dont know if you are aware of it, but in the first pic, the large comment box has obscured all the smaller inner ones, so all you can see is the "project box radioshack" comment. Perhaps you can edit it to be long and thin highlighting the top of the box so that it doesnt obscure the others.

Overall, nice one, good pics and covered all the details.
Yettimania (author)  petercd9 months ago
Yes!!! Thank you for pointing out