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Topic: Can my Arduino burn up if my voltage regulator overheats? (Read 1 time) previous topic - next topic

Chagrin

An LM78XXCT (and most other linear regulators -- check your datasheet) has thermal overload protection. Not that that is something you should rely on; it's still very easy to vaporize them if you overload them quickly.

Your LM7809 regulating 12V down to 9V at (e.g.) 1A will burn off (12 - 9) * 1 = 3W of heat. That's just how linear regulators work. 3W might not seem like much but it is.

Switching regulator modules based on the LM2596 can be purchased on eBay for under $2 each. They are much more efficient (~90% or more) than linear regulators and should be used for projects that are driving more than ~500ma consistently or when you're on a battery.

mattrloper

So should I order the LM2596?  Just to make sure.  I have 4 cameras, a DVR and about 5 sensors, also a key pad (that takes up seven of my pins) and I will eventually hook up some burglar alarms when I have this thing fully constructed plus an LCD screen.  Every one of the pins on my uno will be in use.  How much current would that be pulling?  And if I order this voltage regulator what voltage would you suggest I keep it on?  Is 9V too high?  I will have to go out and buy a new arduino because I must have burnt something up.  It is acting funny and I didn't change any of my code or hardware other than hooking that regulator to it.  Thanks for all your help.


cjdelphi


Yes. There was a post today where the user actually vaporized one of the regulator pins.
Use an external regulator (such as LM317) and bring the input voltage down to 7.5V.


While yes, any arduino clone, anything over 9v will usually fry the regulator, the official one supports 12v just fine, the cheap ones (cloned with cheap parts) don't they get so hot and let the current through that in turn gives 9v+ to the poor microprocessor.

however.

Can my Arduino burn up if my voltage regulator overheats?

depends what the voltage regulator it is..... that should answer the question properly, i can't imagine a lm317 doing anything but reducing the current if there's a short or overload.




fungus


I have 4 cameras, a DVR and about 5 sensors, also a key pad


...but you can't afford a proper 5V regulated power supply, you're relying on the Arduino's tiny onboard regulator?

No, I don't answer questions sent in private messages (but I do accept thank-you notes...)

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