LED lighting characteristics
1. The meaning of the limit parameters (1) Allowable power consumption Pm: The maximum value of the product of the forward DC voltage applied to the LED and the current flowing through it. Above this value, the LED is hot and damaged. (2) Maximum forward DC current IFm: The maximum forward DC current allowed to be applied. Exceeding this value can damage the diode. (3) Maximum reverse voltage VRm: The maximum reverse voltage allowed to be applied. Above this value, the LED may be damaged by breakdown. (4) Working environment topm: The ambient temperature range in which the LED can work normally. Below or above this temperature range, the LED will not work properly and the efficiency will be greatly reduced. Under the premise of not changing the material, in the limit range of the LED, the means to increase the brightness is to increase the current, and as the current increases, the amount of heat generated by the LED will increase sharply. Friends who have used LED light source portable projectors, or micro-projectors, must have a deep understanding, LED light source projectors, very hot, and generally there will be significant noise. These products, the small body is on the one hand, the key is still caused by its own heat. With the increase of power, the heat dissipation problem of LEDs becomes more and more prominent. A large number of practical applications show that the basic reason why LEDs can not increase the input power is because LEDs will release a lot of heat during the working process, making the junction temperature of the die quickly. Ascending, the thermal resistance becomes larger. The higher the input power, the greater the heating effect. The increase of temperature will lead to device performance change and attenuation, non-radiative compound increase, device leakage current increase, semiconductor material defects increase, metal electrode electromigration, encapsulation epoxy resin yellowing, etc., seriously affecting the photoelectric parameters of LED. Even the power LED is disabled. Therefore, for LED devices, it is increasingly important to reduce the thermal resistance and junction temperature and to study the thermal characteristics of LEDs. Industrial Vacuum Cleaners Series Industrial Vacuum Cleaners,Large Industrial Vacuum Cleaners,Industrial Wet Dry Vacuum Cleaner Bontai Diamond Tools Co., Ltd. , http://www.fjdiamondblades.com