Overvoltage Protection for the LM317


Posted on Sep 3, 2012

This is an add-on Over Voltage Circuit for the LM317 Regulator Circuit submitted by Matthew Hewson. It is a voltage regulator that allows a 6v portable supply to be derived from the 12v car battery. You can add a 6.2V zener diode and a LED to warn you when the input supply is overvoltage. If you could find a relay that would operate from 6.2v right up to 12v that you could connect in such a way that if over voltage occurred, then the relay would automatically switch off the output preventing damage to any connected equipment.


Overvoltage Protection for the LM317
Click here to download the full size of the above Circuit.

Such a relay would be quite difficult to find, so I designed this, it is a simple two transistor circuit which will switch off the output should the voltage raise above 6.2v (this can be changed by selecting a different value of zener diode ). Double c




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

SOLAR REVOLVER
Fm-mpx-sca-receiver
Electrolytic Capacitor Reforming Circuit
Bedini Motors
Joule Thief
TDA7275A DC motor speed controller circuit
Symmetrical power supply circuit electronic project
A Cmos Based Motorcycle Alarm circuit
Zener Diode Tester Test Gears Circuits Schematics
Polaris Jet Ski Model SLTX 1050
ESL amplifier circuit diagram
Ultrasonic drilling machine circuit
Using PLL Phase Locked Loop IC frequency N 1 to 10 of the multiplier circuit
Motor Speed and Speed protection circuit of small hydropower stations



Top