Mini Variable Power Supply




About: Diy and gadgets

Check the video above for all the steps

List of material used:

- Dual meter Here or Here

- Module DC Here or Here

- 10 k Potentiometer Here


- 10k Precision Potentiometer Here or Here

Step 1: Prepare the Case

i used some aglomerate wood to do the case, you can use another tipe of wood or plastics

Step 2: Finishing the Case

Cut a piece of plastic(i used some dvd case) to fit on front part of the case, use 4 extra pieces of wood for extra support, when its dry sand it for a better look.

Step 3: The Module

Unsolder the blue potentiometer on the module and solder a 10k potentiometer , isolate all the conections with shrink tube.

Step 4: First Test

Using the schematic:

1º-Power the DC Step-Down module using a transformer from 4 to 30 volt, connect the amp meter to the source "in" 2º-The yellow wire is pluged to the "out" positive side of the buck converter 3º-The remaining bigger black wire is conected to the "out" negative side, the the red is the output negative

Step 5: Final Drills

Measure the meter and mark the holes for the potentiometer and the positive and negative power output, cut it and trimm it until it fits good, do the same for the power button.

Step 6: Back Cover

Measure and cut the back cover, mark the place for the power jack and cut the plastic to fit.

Step 7: Final Steps

Just solder everything just like the schematic, hot glue the module and close the case with small screws

Step 8: Lets Test It

it works ! Simple, cheap and easy, good for small led and motor tests



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7 Discussions


Question 6 months ago on Step 8

What is the power adapter rating required to operate this Power Supply?

2 answers

Answer 6 months ago

Hello,now i´m using a 19 volt 6 amp laptop charger, the max amount of amp for that module is 3 amp, when using don´t exced the 3 amp, normal use up to 2 amp load is ok for that module.


Reply 6 months ago

Thank you, well done project!


1 year ago

clean & easy power supply!! being an eletro hobbist, I m going to make one for my projects, wish I had seen urs sooner, I ordered already parts for make one from an old ATX... unfortunatly more complicated, your version would had been more that anough for me....

1 reply

Reply 1 year ago

Tank you, yes, its very simple and easy !