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How to over- power an led with arduino ? Answered

Is there a way to draw max (or even more than max) current to a LED with arduino as the controller ? 

The LED is a high power LED that use a 12V source. I used a power MOSFET IRF620 as the driver. My application is that I flash the LED on and off in a very short amount of time (strobe light). (the on time for the LED estimate is about 20-50ms). So without modify anything, the light give out is quite dim. I want the LED to draw out much more current in that short amount of time to enhance the brightness. 
IS it possible to do that ?
Yes, I am aware that doing so might shorten the lifespan of the LED and I will add a transistor in between the arduino and the power MOSFET just for an extra layer of protection. 

EDIT: This is the spec sheet that they sent me. Most of them i think are pretty bs. 
https://drive.google.com/file/d/0BwYTLuvu7CiTS0RaTEZnRU9hQ3M/view?usp=sharing

Tags:LED

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iceng

Best Answer 2 years ago

Leave all your Arduino outputs wired together. Make sure at power-uP the Arduino sets all outputs to tri-state mode.

Then: clip the target LED to plus 5 volt and and all the outputs with NO_Series_Resistor.

Next: ready the program to set all the outputs low while still in tri-state mode.

Finally:
at a button depression load a word into the status register to make all
of the digital lines into outputs at one time, for the duration of the
button press...

Conclusion: The sum total current of all the Arduino digital lines added together will flow through the target LED !

This may do what you wish to the LED and risk the Arduino too.

So be ready to pull power if Arduino gets too hot to touch in 30 sec...

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steveastroukiceng

Answer 2 years ago

You are sometimes not a nice man :-)

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icengsteveastrouk

Answer 2 years ago

Yea, a bit of evil is refreshing now and then :-)

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-max-

2 years ago

I connected a 10W CREE XML T6 power led to a fully charged 12v 470uF (if I remember) capacitor and it blew it to smithereens. There was a huge black char where the yellow die used to be lol! Yes you can overdrive them for very brief periods. How much is basically dependant on how well it can dissipate the heat energy.

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-max-steveastrouk

Answer 2 years ago

The bond wires so happen to be the weakest point for overload, at least compared to the comparatively large surface area of the chip. It is still the same overheating type of failure as the bond wire vaporizes right? My single die CREE chip did not die from bond wires failing, the actual chip itself was blown. For smaller cheaper LEDs I totally agree the bond wires are what fail first. Most of my "dead" LEDs will light up in the presence of a very strong electric field produced by tesla coils.

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steveastrouk-max-

Answer 2 years ago

Yes, it depends a bit on the nature of the overload, but the bond wires will explode sometimes. If there is enough energy, you now have a plasma channel which allows even more current through the LED.

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steveastrouk

2 years ago

Yes, its possible, up to a limit which is usually in the datasheet. You reach a point when even the pulsed current will blow the wires on the LED die.

Most Mosfets will readily supply enough current to do that easily. Even the 620 will push 5A into a fast pulse.

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Jack Vusteveastrouk

Answer 2 years ago

So if it is possible, How do I do that ?

is that something has to do with the code or the hardware?

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verenceJack Vu

Answer 2 years ago

Use a higher voltage. For very short pulses, an LED can handle much more current than in static mode. To drive more current, you need a higher voltage. Good data sheets have some information about the pulse capabilities. Or just try it out. Of course, should the driver pin stay in the on state, the LED will be toast.

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Jack Vuverence

Answer 2 years ago

Yeah. this actually make sense. Ill try this out and see if they gonna blow up to my face. Because the spec for thoese LED are not really accurate (you know how floater electronic from china works), may be I will get lucky :D.

Thanks

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-max-Jack Vu

Answer 2 years ago

Push more current into it. More voltage will help you do that.

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seandogue

2 years ago

Presuming a the FET on time is fixed to 20-50ms and the voltage is fixed, no you can't magicially force more current through the LED. If you increase the on-time, yes.

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iceng

2 years ago

Early blue leds could be stimulated to put out UV for narrow overloads.

What did your yellow led show as before turning black Max ?