DIY, 3D Printed, Variable Power Supply

Hi in this instructable I will show you how to make your own variable power supply, which is capable of delivering up to 5A at 12V.

For this project, you will need mostly parts from eBay and local hardware shop. You will also need some basic tools like soldering iron, knife, solder, screwdriver. I put international purchase links below:

step-down
step-up
step-down 5A
potentiometer
screw terminal
male dc plugs
display
banana plug
ON OFF switch
power supply
Circuit board

Get all necessary components together and testing them out first to see if they are working correctly.

So I powered my display as shown on wiring diagram then I connected 12V motor to the terminals and started rotating potentiometer to see if display functions correctly. Next up was the step-down module and lastly step-up.

This step is optional but it will make your life a whole lot easier when you assemble power supply. Start with laying down some terminals and solder one-half of terminals to common GND and 12V.

I designed case in cad software Fusion360. You can download stl file.

First I inserted all potentiometers and banana plugs that I saw how everything fits together. Next up I desoldered all trimer potentiometers and soldered some UTP wires from old internet cable and soldered ends to potentiometers, I added some 0.75mm wire to ends of banana plugs and put them on ends of regulation modules.

Cut some wire and solder to the switch before power distribution and parallel to LED.

Here are some of the voltages.

This step is optional but is really cool to have some indicating light, color does not matter I even used a bicolor diode and trimmed one leg away. First I checked operating voltage of the diode (which was 3,3 V) and then added 2k ohm resistor in serial. And it worked fine and it looks awesome.

I made two pairs of plugs one for the perfboard and one with alligator clips. If you want to make some too just follow pictures. I used some fine needle so I can stick inside some female plugs of arduino.

This project was really fun and educating for me. I had some problems with 3D print but at the and everything turned out great. I even have to heat one side of the enclosure to fit all together.