How to Make Adjustable Bench Power Supply Out of an Old Pc Power Supply




Introduction: How to Make Adjustable Bench Power Supply Out of an Old Pc Power Supply

About: HI,I am Emon.I am 17 years old boy from south Asia.I love science.I like to make random project.

I have an old PC Power Supply laying around.So I have decided to make an adjustable Bench power supply out of it.

We need a different range of voltages to power or check different electric circuit or projects.So it always great to have an adjustable power supply.So I am building an adjustable Bench power supply out of an old PC power supply.


1. LM317 Voltage Regulator

2.10k Ohms Resistor

3.470 Ohms Resistor

4.50k Variable Resistor

5.Heat Sink

6.Mini Volt Meter

7.Dc Connector



10.And a Power Supply Unit

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Step 1: Preparing the Power Supply.

Open the power supply unit.In this project, you don't need all the wire of the power supply.You need the green color wire for turning the power supply unit on because it makes the power supply unit on when it connects with the ground wire.You need yellow color wire as they provide 12 volts and Orange wire for the indicator led and of course the black wire.You should cut off any extra wire for keeping the project neat and clean.

Step 2: Making the Enclousere.

Marks the outline of the compartments with a pencil and cut it.I have used drill and hacksaw to cut it off.Always be careful when cutting stuff.

Step 3: Adding the Switch and Indicator Led.

Solder a switch between the green and black wire and seal the bond tightly with the heat sink.Add 470ohms resistor with the positive terminals of the led and connect it with the orange wire.Also, connect another pin of the led with the black wire.

Step 4: Now It's Time to Make the Adjustable Voltage Regulation Circuit.

Solder all the compartments in the Vero board according to the diagram.Now connects the circuits with the yellow wire which will provide 12 volts to the circuit.

Step 5: Assembling the Power Supply.

Now connects all the part.Also add a dc jack directly to the 12 yellow wire it will provide unregulated 12 volts output.Seal all the connections with the heat sink.Check everything again before closing the enclosure..And you are all done.

Step 6: Checking the Power Supply.

Connect the power supply to the power source.Turn on the switch.Adjust the output voltages by turning the knob..Enjoy it! Please rate this guide if you liked it!

Youtube link to the project

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    4 Discussions


    2 years ago

    Thanks for sharing :)


    Reply 2 years ago

    Welcome :)


    2 years ago

    That's pretty cool looking. Does it just get it's power from a 12v battery or do you have to plug it into an outlet?


    Reply 2 years ago

    The power supply unit converts 12 volts from 120 volts AC.