LED lighting application trends and heat dissipation problems have continuously improved due to Solid State Lighting technology, which has improved the lighting efficiency of LEDs in recent years and has gradually replaced traditional light sources. At present, the lighting efficiency has continued to grow upward.

And some companies have developed LED components with an efficiency of 100LM/W, which has also made LED lighting applications wider and wider. Not only has it begun to be applied to indoor and outdoor lighting, mobile phone backlight modules and car direction lights, etc. In the application of strong light lighting, large -sized backlight modules, and car headlights such as high -wattage lights and street lights. Due to the advantages of power -saving, environmental protection and long life, the trend of LED light sources as its mainstream in the future is becoming more and more obvious.

In order to make the LED more brighter light, you need to enter higher power. However, at present, the photoelectric conversion efficiency value of high -power LED is still limited. Generally, only about 15 to 25% of the input power becomes light, and the rest will be converted to thermal energy to heat energy. Essence Because the area of the LED chip is small, the heat (thermal density) of the high -power LED unit area is very high, even more serious than the general IC component, which also increases the connector temperature of the LED chip. Essence Excessive chip connector temperature will reduce the light brightness of the LED, and the attenuation of red light is the most obvious. It will also cause the wavelength offset of LED to affect the color, and it will also reduce the reliability of LED. Therefore, heat dissipation technology has become the bottleneck of the current development of LED technology.

Therefore, the challenge of heat dissipation design must be large. It must be from the chip level, packaging level, PCB level to the system module level. All must attach great importance to the heat dissipation design and seek the best heat dissipation recipe. For LED lighting products, due to the large heat dissipation limit on the system, the heat dissipation demand at other levels is even more obvious.

For LED heat -passing problems, the most basic analysis method is to use thermal resistance network for analysis. That is, the main heat dissipation path from the chip thermal source to the ambient temperature to construct the thermal resistance network, and then analyze the characteristics and size of each thermal resistance value. This can calculate the chip temperature when the ideal situation is calculated, and for each part of the thermal resistance network, it can be calculated. Countermeasures to reduce thermal resistance. It should be noted that in actual analysis, it can form a more detailed thermal resistance network according to the system structure, such as considering the thermal resistance of DIE ATTACH materials and Solder and other interface materials, or the heat resistance value of the heat dissipation module structure.