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Unread 24-01-2004, 18:46
KenWittlief KenWittlief is offline
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Re: Making a beacon indicator LED burn its brightest without burning out

hooking it up to the battery directly will only blow it out in seconds, and you wont learn anything (expect to not do that :c)

LEDs work on current - the series resistor is there to limit the current.

when you pulse an LED rapidly, say at a 1000 Hz, then the heat at the juction dissapates a little between the ON part of the cycle, so you can drive it a little harder

but if you pulse it at, lets say, 1 Hz - the junction temp rises fast enough that it will burn out

you really need to get a hold of the spec sheet for the LEDs - I dont know if FIRST listed the supplier and part number for those - if they did you should be able to goto the suppliers website and get the data sheet.

It will tell you the max (do not exceed) current - and most LED manuactures data sheets explain what you need to know (the levels) when pulsing them instead of driving them steady.

BTW, if all you want to do is make it appear brighter, I dont think pulsing it with more current will do that - driving it at its rated steady current level will be as bright as it can get.