2006-12-29 02:32:44 · 6 answers · asked by nicholastan_tlk 1 in Science & Mathematics ➔ Engineering
A light-emitting diode (LED) is a semiconductor device that emits incoherent narrow-spectrum light when electrically biased in the forward direction. This effect is a form of electroluminescence. The color of the emitted light depends on the composition and condition of the semiconducting material used, and can be infrared, visible or near-ultraviolet.
2006-12-29 02:35:32 · answer #1 · answered by sarabmw 5 · 0⤊ 0⤋
LEDs are pretty much similar to normal diodes when it comes to characteristics. Why don't you try it yourself.
Take a variable power supply, connect a current limitting resistor in series, and an LED. And then give it different voltages, Make sure it's less than 4 volts to prevent diode getting burned out.
Measure the voltage and current using a multi meter, and plot a graph...
A typical indicator LED has a forward voltage rating between 2 and 4 Volts of DC. You may see maximum ratings above that. A typical drive current for indicator LEDs, even high-brightness ones, is 20 milliamperes (mA).
2006-12-29 02:48:17 · answer #2 · answered by Niks 3 · 0⤊ 0⤋
Light emitting diodes, commonly called LEDs, are real unsung heroes in the electronics world. They do dozens of different jobs and are found in all kinds of devices. Among other things, they form the numbers on digital clocks, transmit information from remote controls, light up watches and tell you when your appliances are turned on. Collected together, they can form images on a jumbo television screen or illuminate a traffic light.
Basically, LEDs are just tiny light bulbs that fit easily into an electrical circuit. But unlike ordinary incandescent bulbs, they don't have a filament that will burn out, and they don't get especially hot. They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor.
Please see the web pages for more details on "How Light Emitting Diodes work".
2006-12-29 03:02:06 · answer #3 · answered by gangadharan nair 7 · 0⤊ 0⤋
There are a number of different characteristics:
The color (or wavelength) of the output.
The forward bias voltage drop.
Power
current
reverse bias breakdown voltage
physical size
type of lens
case style
and on and on.
2006-12-29 03:24:02 · answer #4 · answered by Deirdre H 7 · 0⤊ 0⤋
Longevity of it. LED lasts for years!
2006-12-29 02:34:48 · answer #5 · answered by Fantasy686 4 · 0⤊ 0⤋
linear(?)
2006-12-29 02:34:37 · answer #6 · answered by JAMES 4 · 0⤊ 0⤋