what are the characteristics of a light emitting diode?

Last Update Time: 2018-10-26 16:17:19

what are the characteristics of a light emitting diode?

Light emitting diodes have the same conductivity as ordinary diodes.When positive currents pass through PN junctions,

PN junction will glow.They are widely used in display,indication,remote control and communication fields.

Common light-emitting diodes are: plastic LED, metal shell LED, round LED, square LED, special shaped.

LED, discoloration LED and LED digital tube and so on.

what are the parameters of an ordinary light emitting diode?

the structure and performance of monochromatic light emitting diodes. Monochromatic light emitting diodes (LED) are electroluminescent devices.

The semiconductor device, shown in Figure 5-13,is the circuit symbol and internal structure of the monochromatic light emitting diode.It is similar to the ordinary diode in that it also has one way conduction characteristics.The LED can only turn on the light when it comes to the receiving circuit. The fundamental difference between light emitting diode and ordinary diode is that the former can convert electric energy into light energy,and the pressure drop of tube is larger than that of ordinary diode.

Monochromatic light emitting diodes have different materials and produce different colors of light.

characteristics and parameters of monochromatic light emitting diodes

The main parameters of LED are the maximum current Iem and the maximum reverse voltage UeM.

The two values will be damaged, otherwise the LED will be damaged.

The characteristics of the light emitting diodes are as follows.

It can work at low voltage and is suitable for low voltage miniaturized circuits. For example, the typical working voltage Vp of the common red LED is 2V; the typical value of the positive working voltage Vp of the green LED is 2. 3V.

with a small current,high brightness can be obtained,and the brightness will increase as the current increases.The luminance can be changed in a large range according to the size of the working current,but the luminous wavelength is almost unchanged.

The required drive display circuit is simple and can be directly driven by integrated circuits or transistors.

the response speed of the luminescence is fast, 10~7s or 10~8s.

Small size, high reliability, low power consumption, good vibration and shock resistance. What are the notices for the use of ordinary light emitting tubes?

First,we should prevent the use of over current, and damage the tube to prevent the overcurrent caused by the power supply voltage fluctuation.In use,the working current of the protective resistance R.light emitting diode should be connected in the circuit to determine its luminance.Generally,the luminance of the light is determined when Ip=1mA,with the increase of the luminance of the Ir,the limit of the luminous one pole is IFM in general.For 20~ 30mA,exceeding this value will cause the tube to burn down, so the working current I should be selected in 5~20mA mushroom.

It is more appropriate in the enclosure.The general selection is about 10mA.The current limiting resistance is selected as R= (Vcc-Vp /

The starting voltage of -Vp is 2V and Ir is the working current.10mA is generally selected; second,the welding speed is fast.