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This question already has an answer here:

I'm trying to control my RGB LED strip with my arduino, using IRLZ34N MOSFETs according to this schematic

schematic

simulate this circuit – Schematic created using CircuitLab

I tried it out, everything worked. I soldered it to a circuit board just like that, except for that I used 4 copper wires on the Arduino connections. Everything worked, I unplugged the copper wire from the Arduino and checked back ~3 Days later, then this happened:

The strip was slightly glowing, even when the gates of the MOSFETs are directly connected to ground. Connecting a Gate to +5v made that color glow fully though. That's pretty much my problem, some deeper examining got me those Results:

I desoldered the mosfets and my multimeter reads a resistance of ~290;310;350Ω between Drain and Source. Another strange behaviour is that the conduction seems to go from 0-100% really fast. My LED strip goes from the constant "slightly on"-State to 100% brightness in a matter of some mV. Also strange is that this happens at ~4.7V on the Gate, while my fully functional IRLZ34N gives the strip 0-100% brightness at around 1.5-2V. I also tried to shorten Gate-Source and Gate-Drain, booth changed nothing. So my conclusion was that I probably destroyed the MOSFETs, but still the question is: How? Because I want to do the setup again (of course with new MOSFETs) but without killing the MOSFETs.

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marked as duplicate by winny, Passerby, Wesley Lee, RoyC, Finbarr Apr 23 '18 at 9:06

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Source an enhancement mode power mosfet. Because it seems like the one you are trying to use is a depletion mode type. (or at least behaves like one in your circuit)

Also you should have a resistor in series in the gate circuit so that there is no stray currents developing between the output of the micro-controller to the mosfet. 1K is typical there.

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There are a number of ways to destroy a MOSFET as you describe, one of which is allowing them to get too hot. If you can't hold your finger on the metal tab, it's too hot for comfort. If so, add a heatsink.

Another way is to expose the gate-source insulator to more than the rated +/-10V. This is conceivable with really horrible layout.

One way to protect them against the latter is to add some series resistance, say 1K, from the Arduino, increase your 10K resistors to 100K and put a 5.1V Zener eg. 1N751, from gate to source (reverse bias, of course). The series resistance helps protect the Arduino and also slows the transitions making the layout less sensitive to stray inductance and perhaps excessive load capacitance.

I presume your strip has appropriate series resistance to limit the current, if not, that is something that is required.

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