How do LED (Light Emiting Diodes) work?

[chiwawa626]

How do LED (Light Emiting Diodes) work?
I need to do this in chemistry for a project, i need any research i can get on this...and also anyone have some LED's i can buy for cheap from them?

 

[Silverbullet28]

Go here for a little tutorial on them.

http://www.mcdelectronics.com/led101.html

Also, you can just go to radio shack and get a pack of three or so, for a buck and some change.

- Silver

 

[squirrel dog]

Radio Shack has them in all sizes for as little as $1.00.You will need a resistor connected to the long leg(+) or 12vlts dc will roast it.5vlts will too.Leds are neat.

 

[toph99]

i just hooked up an led to a 9V battery, didn't fry it

 

[rudds]

i want to replace the leds in my pc case with some prettier colors. anyone know where i can buy offbeat led colors like blue and purple? radio shack only has the standard red, green, and yellow variety (booooring).

 

[chiwawa626]

i found this electronics store that sells all this stuff they buy out from companys, im gonna go see if they got some led's, and buy a big ass battrey for a demonstration on my research project

 

[squirrel dog]

its the amperage that cooks them.A 9vlt battery has very little,The pwr supply on your pc will fry it,try it out.They burn white bright for about 3 seconds.

 

[Prodigy^]

hehe I've tried putting 220V through one of those LED's and it still works

 

[pac1085]

I have a whole bunch of em...they get really hot and burn up when connected to a 9v battery

 

[ArkAoss]

if you read the article unforutnatly colors are limited to red green yellow blue and white. .maybe you could put a lens over a white to get purple, or rig a red and blue to an optic channel and get purple, just ideas

 

[rudds]

hmm, radioshack.com seems to have purple LEDs, but i may have read it wrong

 

[chiwawa626]

howmany volt batrey should i get? and the amps? like a 4volt or a 6volt?
This place i found has battreys for stuff like exit signs, and they are pretty compact and not that expensive and u can get anything from 3-12v

 

[xaigi]

>> How do LED (Light Emiting Diodes) work?

Every LED has a tiny 80s rock concert inside. When current is applied, the micromunchkins (smaller than picomunchkins, but larger than minimunchkins) inside all click on their lighters simultaneously. You should give your LEDs fresh air and water weekly, or you risk micromunchkin decomposition.

 

[etech]

"howmany volt batrey should i get? and the amps? like a 4volt or a 6volt?"

It depends on the LED's you get. The LED's brightness is determined by the current flowing through it. A common amount is 20 mA. You will need to check the specs of the LED's you buy to confirm what current they are rated to run at.

Some LED's have a dropping resistor mounted internal to them. They will also have a voltage rating , ie 5V or 12V. All you have to do with them is match the power supply(battery) to that rating.

If you get the type that does not have a droping resistor then you will need to use one or there will be too much current going through the LEDs and they will burn out.
There will be a spec on the them such as 20mA @ 1.2V. That means with a 5 volt PS you need a resistor to drop 3.2V @ 20mA.
Subtract the voltage across the LED from the PS voltage. Divide that by the reccomended current through the LED and you will have the resistance you need. In this case 160 ohms. Don't worry about exact values, a 150 to 180 ohm resistor would work.

The amp rating of the battery is only important for how long it will last.

 

[chiwawa626]

ur scaring me, im a retard not that smart, howmany volts and amps does a motherboard usualy give to power LEDs?