Product process influnce on the life of white LED

Packaging Method

With a good LED chips, but also the package of scientific methods in order to obtain white LED light sources with longer life expectancy.

First, the white LED packaging materials used for analysis. Fixed LED chip die attach adhesive used with conductive adhesive and insulating plastic of the points, if the LED chip as the L-type electrodes, conductive adhesive must be used, this solid crystal gel can both thermal conductivity. If the LED chip is the V-type electrode, then use a good thermal insulation properties of rubber as a solid crystalline gel.

Second is the choice of pin-type package of support, the current stent made ​​from two materials: one is the iron frame, the appearance of silver; other is a copper stent, appearance is silver plated. Thermal conductivity of these two materials are different, the difference is relatively large. Usually made ​​of copper stand than LED LED made ​​of iron bracket more than doubled its long life.

pn junction temperature

Theory and practice have proved, LED and LED life is the pn junction temperature closely related. pn junction temperature is generally between 110 ~ 120 ℃, but the design should consider the case of long-term work, pn junction as far as possible kept at 100 ℃. When the LED chip junction temperature rise 10 ℃, the flux will decay 1%, LED chip, the main wavelength of light will shift 1 ~ 2nm.

For the white LED, white LED temperature on the life of great influence. Pn junction temperature rise on the one hand, to promote increased lumen; the other hand, the main emitting wavelength shift to promote, but also affects the effective excitation light on the phosphor, light failure not only increases the color temperature can make a difference. Because the dominant wavelength changes, changes have taken place excitation of the yellow, the result and the original mix of light to different color temperature of light.