Simple Variable Voltage Regulator Circuit with LM317 circuit

Here is a simple variablevoltage regulatorusing ic LM317 circuit. Thevoltage regulatoris an  LM317T,  and should accept up to about 14 volts without problems. It can handle up to 1 amp, but you WILL need a heatsink on thevoltage regulator. If you only plan to use items that run on one voltage, this is a very useful feature and will save plugging in and damaging your valuable (or not so valuable) equipment. You can even add a relay to switch off the power if the over voltage LED turns on, but bear in mind it will have to work from the voltage of the zener diode right up to the input voltage. The over voltage LED uses a zener diode to switch on the LED at a certain preset voltage, this can be varied depending on the voltage of the zener diode, I used a 6.2v zener diode.

Here is a schematic variable voltage regulator:

part of list variable voltage regulator circuit:

R1: 270R
R2: 2K Cermet or carbon preset potentiometer
C1: 100nF
C2: 1uF tantalum
LM317T Voltage regulator
Heatsink
PCB board

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