## Introduction: LM317 Adjustable Voltage Regulator

What you need

LM317 voltage regulator

100 om resistor

potentiometer

1uf 50v electrolytic capacitor

.01 uf ceramic disk capacitor

Also this is my my first how to make something thing so dont expect it to be good

## Step 1: The LM317 Voltage Regulater

**(The pinout is in a different order then the circuit diagram) The LM317 id adjustable voltage regulater that can regulate voltages from 0v- 33v, but you have to have 33v coming in and if you are going to have 33v coming in you should put a heat sink on the regulater. Here is the formula to figure out how much voltage is coming out. Vout=1.25*(1+R2/R1)+ 50u*R2**

## Step 2: Final Product

The final product

## Discussions

Good first attempt at an instructable! A couple of questions:

1 - Which resistor is R2 and which is R1?

2 - I know that the equation for output voltage came from one of the usual datasheets for the LM317 but I have a pet peeve with this equation appearing in datasheets. That is, that nearly no one that is building such a circuit needs to calculate the output voltage given the resistors. Usually when one builds it he/she needs to calculate the resistor values given the desired output voltage. Perhaps you could explain how that is done.

3 - The necessity of a heatsink is determined by the amount of power the LM317 is likely to dissipate. How do you know if it is needed and how would you choose one since there are thousands to choose from?

Otherwise good going.