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short circuit protection for power supply

erfan

Aug 11, 2014
1
Joined
Aug 11, 2014
Messages
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I built a power supply with lm338.
But if a short circuit occurs at the output.
lm338 burned
I want a circuit if a short circuit occurs, stop the line and turn on a buzzer.
Allowable current: 5 A
Input voltage: 12 V
thanks.
 

KrisBlueNZ

Sadly passed away in 2015
Nov 28, 2011
8,393
Joined
Nov 28, 2011
Messages
8,393
No, don't Google crowbar circuits. A crowbar detects overvoltage at the output of a regulator, not overcurrent.

You really want a circuit in series with the input to the regulator that monitors the current using a shunt resistor and latches into a state where it activates the buzzer and removes the supply from the regulator.

I'll have a think about it and draw up something if you answer all of these questions.

What is providing the input voltage to the regulator?
What is the voltage range of this unregulated supply?
What is the regulator's output voltage?
 
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