Explanation: LED lamp life three often misunderstood parameters

Review: the concept of the current LED indicators, in general publicity, the most likely to cause misunderstanding of the three indicators, namely power, life and efficiency. In this issue, we continue to discuss the parameters - life.

Life expectancy is similar to power, and the concept of life expectancy is also 3:

1, the lamp life of monomer;

2, the practical application of the lamp life;

3, driven life.

The 3 concepts of life constitute the life of the lamp, and the shortest part of life determines the life of the lamp.

Here, I want to make a common mistake, is 50 thousand hour, this statement from Cree, a special note on its website, the idea is: Cree for an independent third party laboratory, in accordance with the LM-80 standard to measure their results, in the "lamps;" under normal use conditions, measured after 6000 hours, the lamp life is 50000 hours results. Cree also notes that any change in initial conditions or parameters will affect the life of the LED in varying degrees. Please take note of this: first, Cree is not the name given independent third party laboratory, so the original record is not open; second, Cree did not give the so-called "normal conditions" meaning, please note that this condition can "and daily use conditions are not consistent; finally, Cree noted. The change of parameters or initial conditions will affect the life of lamps LED. From the above description, this experiment is for reference only, is not very tight, so the 50 thousand hours of life, and can not be regarded as a reliable basis for propaganda.

In general, in the case of fully cooling (here refers to the junction temperature, English writing Tj, 850C work under LED), single lamp life can reach 35 thousand hours. This single life and LED can be compared with the actual work of the lamp. Of course, due to the current market a lot of lamps to do the so-called "full heat", that is to say, often junction temperature LED beads in 950C or 1000C, even more high, so the practical application of the lamp life is shorter. So in general, the practical application of the lamp life than LED monomer beads of short life, especially in the lamp radiating structure is not reasonable and not fully guarantee the case.

Finally, when it comes to LED chronicproblem, is currently on the market mainstream driven life is far lower than the LED lamp life. Of course, the problem is due to the nature of technology driven structure unreasonable, resulting in efficiency is not high, so that the temperature rise is high; because the temperature distribution is not uniform in structure, and LED driven life greatly reduced.

To sum up, these three concepts constitute the life of LED lamps, which is currently the main constraint is LED driven life.