LED question

[bassmasta17]

I found a LED and when i put it to a 9V it was green. Then it turned red the amber. It stayed amber for a cupple of seconds before it started to smell. What is this?
saw this also. Is it the same thing?
http://www.diystompboxes.com/smfforum/index.php?topic=53152.0

[oskar]

You need a resistor in series whith the LED. You fried it good! 

Then it turned red the amber.

Should be green...

It stayed amber for a cupple of seconds before it started to smell.

-schience!

What is this?
saw this also. Is it the same thing?
http://www.diystompboxes.com/smfforum/index.php?topic=53152.0

Only without the smell...   
That's what were discussing in this thread...
http://www.diystompboxes.com/smfforum/index.php?topic=53152.msg594447

[lorddracula_me]

why it did so:
there is (on average) a 0.6-0.7 volt drop across a diode/led, it is also fixed, so the drop cannot change, so where do the extra 8.3 volts go? in the resistor you did not put in:) no worries, it happens, but your led is dead

[bassmasta17]

i did have a resistor in between. It did this multiple times. Checking the link out now. The LED still works also.

[oskar]

http://www.muzique.com/schem/led.htm
Hit this link instead. Here you can fill in a lot of numbers and find out what the resistance should have been.
The voltage drop over a green LED is more than 2v I think. Check a datasheet.
I don't know how green LED's generally are supposed to behave. Especially not the smell of them.
I however encourage you to do a full study of the subject...   
Is the smell voltage or current related?
How do I simulate it in LTspice?   

I have managed to melt holes in IC's and the circuit would still function. I wouldn't put it in something that that would end up with a customer though...
It either is a new LED that is normally green but sometimes goes red and gives off a scent... or it is a green LED that was fed too much current... Hmmm.       how big was the resistor?

[bassmasta17]

well i wired it with out a resistor at first because i didnt care about it. When it changed colors i cared. I dont remember what resistor i used. I just grabbed one. It was along time ago. I just read a thred here and remembered. I might play with it some more soon.

[GREEN FUZ]

Sounds like it was a bi or possibly tricolor LED. The smell is a fair sign that it`s now useless.