Introduction: ATX Power Supply Recycled With Variable LM317

Picture of ATX Power Supply Recycled With Variable LM317

This project was started more than a year ago when it tried to reboot
floppy disk drives and CD / DVD drives, and the need to build a benchtop power supply. I think all hobbyist need to have a benchtop power supply as support for their jobs and experiences in their evolution and fun. This project is based on two conditions: the need for a benchtop power supply, and the recycling of electronic equipment (ATX supply). After searching through the dozens of projects on the internet, and after tens and tens of hours of watching videos and project diagrams, I worked out the layout of my setup with the idea of using multiple outputs at the same time, and still have an adjustable output.


Initially I was thinking of using a voltage regulator scheme, of the several I saw, but then I found this little circuit that uses the LM317 as a regulator and with positive references, and in this way I simplified a few steps and streamlined the process of building the bench source.

Some steps, such as opening the power supply and cutting wires and their identification can visit this link. This power supply has no 3.3V power.

Step 1: List of Materials:

- ATX supply (offered)

- voltage regulator

- digital voltimeter ammeter

- switch

- terminal connector

- potentiometer

- weld

- thermal sleeve

- bolts, nuts, washers

- hot glue

Step 2: Tools:

Picture of Tools:

- welding iron

- drill

- hot glue pistol

- saw

- fork wrench

- scissors

Step 3: Construction

Picture of Construction

Some doubts have arisen with some components:

- switch - I chose this switch for wanting to have a headlight on the device when it was switched on, and when I bought it I had no instructions, and I did not find any datasheets ... after the consultation of those who understood the subject, explained the operation of this switch.

- digital voltimeter ammeter - This component is a success and it was easy to find information about your assembly.

- potentiometer - this component has been a uneasiness to my mind, because the potentiometer does not have a linear division in the voltage regulation. As the circuit of the LM317 is already built, I did not dare to modify it, but it is something that I will solve.

Step 4: Testing

Picture of Testing

Step 5: Conclusion

Picture of Conclusion

Overall, I am satisfied with this project, which will be very useful in the projects and works of hobbyist, and not only. This construction can be used as is, or be able to be detach the front panel and add to a modular panel with other appliances.
My english is not the best.

I hope you enjoyed!!!

And vote for me !!! Thank you!


DIY Hacks and How Tos (author)2017-07-08

Nice design. So your current is limited by the LM317 right? Is there any easy way to get higher output currents?

My first question was to find the datasheet of the ATX power supply, which is so old that I could not find information ...
the currents are specified in the datasheet, and in an assembly of
these the current is limited by -12V (lower current), and by forcing the
fan to stop at 12V I had a register of 0.6A, but I did not want to force
the materials.
In the LM317 voltage regulator
information (link above), the output current is 1.5A minimum, 2.2A
(typical value), but I think it is limited to the current supplied by
the -12V.

Coutiluna (author)Coutiluna2017-07-10

With the
LM350 can have a current output up to 3A, I saw some assemblies with
this regulator, but with this power supply I want to have multiple
outputs, and I have only 200W, however with a newer power supply and
more watts can make an assembly With a potentiometer controlling the output.

russ_hensel (author)2017-07-09

Welcome to the club: Just a note to let you know I have added this instructable to the collection: Encyclopedia of ATX to Bench Power Supply Conversion


Take a look at about 70 different approaches to this project. This topic is one of the more popular of all instructables.

Coutiluna (author)russ_hensel2017-07-10

Thank you very much !!!
I will see your encyclopedia more carefully, and try to improve the project.

About This Instructable



Bio: Hello !! I am interested in several areas of knowledge, such as electronics, robotics, geology, chemistry, carpentry, arts, mechanics, among others, always mixing fun with knowledge ... More »
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