LED lamp life problem 'hidden rules'

LED is a photoelectric device that uses compound materials to make pn junctions. It has the electrical characteristics of PN junction devices: I-V characteristic, C- V characteristics and optical characteristics: Spectral response characteristics, light intensity pointing characteristics, time characteristics and thermal characteristics. Now many companies are saying that the life of their LED lamps can exceed 5W hours. In fact, is this really the case? The life of LED itself can reach 3 W- About 5W hours, but if you make a lamp, the life will be very different. In the middle and upper class LED lamps, he uses a better power supply, and does not destroy the light (24 hours without turning off the lights) In the case of, the average service life of this lamp is 3-4 years (Every day at 8-15 hours) However, this requires you to use the LED and power requirements are very high. LED lamps, which are as cheap as they are now and have a life span of W hours, are mostly deceptive. Anyone can do such a lamp, it doesn't matter if you use a cheaper one and then repair it several times. What are the profits there. Therefore, the choice of LED lamps cannot only look at the price. In terms of certification, LED certification is now mostly done by domestic laboratories. No matter what kind of LED lamps you make, you can make them at the corresponding cost to the laboratory, so I can't believe that many companies say that we have any certification, and then how good the life is, the price is better than other lamps (Such as ceramic lamps, crystal lamps, etc)Cheaper. The cost of LED is transparent. It seems to reduce the cost if you change a small size chip. In fact, you are cheating consumers. In order to avoid being cheated by the vast number of consumers, the following will introduce the method of measuring the life of LED lamps: the time t experienced by reducing the brightness to Bt = 1/2BO is usually called the life of diode. It takes a long time to measure t, usually to calculate the life span. Measurement Method: Give LED a certain constant current source and ignite 103 ~ After 104 hours, BO, Bt = 1000 ~ 10000, substituted into Bt = BOe-T/find out; The lifetime t can be obtained by substituting Bt = 1/2BO. For a long time, it has always been considered that the LED life is 106 hours, which means that a single LED is under IF = 20mA. With the development and application of power LED, foreign scholars believe that the light attenuation percentage value of LED is used as the basis of life. For example, the light attenuation of LED is 35 and its service life is> 6000 h.