Variable Voltage Regulator Using the LM317

Introduction: Variable Voltage Regulator Using the LM317


today I’m gonna show you how to make an adjustable voltage regulator with the LM317.

Step 1: Watch the Video

The video is in my youtube channel Chris' Project. LInk:

Step 2: The Schematic

Step 3: Buy All of the Components

The components for this project are:

1pc old credit card.

1pc LM 317

1pc heatsink

A screw

1pc 10k ohm potentiometer

1pc 1k ohm resistor

1pc switch

Red and black wires

And a couple alligator clips

Step 4: Put the Heatsink on the Mosfet

Put the heatsink on the LM317 with the screw so the LM317 will not get hot.

Step 5: Glue the Components to the Credit Card

Glue the LM317, the switch, and the potentiometer to the old credit card.

Step 6: The Connection

Solder the resistor to the adjust pin and the output pin. Then connect the adjust pin to the middle pin of the potentiometer, the output pin to the red wire, and the input pin to the other red wire.

Step 7: The Last Connection

Finally, connect the left pin of the potentiometer to the black wire, and the alligator clips to the output wires. And the switch to the red input wires. And we are done.

Step 8: Testing

Now I’m gonna connect the input wires to a 12V power supply and the output to my multimeter. If I turn the potentiometer the voltage will go up and go down.

Be the First to Share


    • Game Design: Student Design Challenge

      Game Design: Student Design Challenge
    • For the Home Contest

      For the Home Contest
    • Big and Small Contest

      Big and Small Contest



    6 years ago

    superrrrrr kid

    nice,and read what the say(ask)to make it more better,then it already is.

    greetings from a fan


    6 years ago

    hey, seems like you forgot to connect the switch?? Over all good effort for showing how the LM317 works. Keep posting more.


    6 years ago

    The circuit does work and is about 100 (give or take) years old.

    It is good for teaching people that are not familiar with the LM317 how to make it variable. I would strongly suggest, to make the schematic logically obvious, put the input on the left with the +ve on top, -ve (ground) on the bottom and the output on the right, +ve on top, referenced to ground. R1 simply goes from Adj. pin to ground in the middle. Much nicer on the eyes.