As we all know, the development of the LED industry has become the most watched industry. LED products have the advantages of energy saving, power saving, high efficiency, fast response time, long life cycle, no mercury, and environmental protection. However, LEDs still have their shortcomings. Usually, about 20% of the input power of LED high-power products can be converted into light, and the remaining 80% of the energy is converted into heat.
We know that if the heat generated by LED illumination cannot be dissipated, it will directly lead to LED temperature being too high, which will affect the life cycle, luminous efficiency and stability of LED products, and the relationship between LED junction temperature, luminous efficiency and lifetime. .
Figure 1 is a graph of LED junction temperature and luminous efficiency. When the junction temperature rises from 25 °C to 100 °C, the luminous efficiency will decline by 20% to 75%, and the yellow light will decay by 75%. serious. In addition, when the operating temperature of the LED is higher, the production life is lower (as shown in Figure 2). When the operating temperature is raised from 63 °C to 74 °C, the average LED life will be reduced by 3/4. Therefore, to improve the luminous efficiency of LEDs, the heat dissipation management and design of LED systems has become an important issue. Before understanding the heat dissipation problem of LEDs , it is necessary to understand the heat dissipation path and improve the thermal bottleneck.
LED junction temperature and luminous efficiency (Figure 1)
The higher the LED temperature, the lower the life (Figure 2)
First, LED heat dissipation
According to different packaging technologies, the heat dissipation method is also different, and the various methods of heat dissipation of LEDs can be roughly illustrated in Figure 3 below:
LED various heat dissipation methods (Figure 3)
Description of the heat dissipation route:
Dissipate heat from the air
2. Thermal energy is directly exported by the System circuit board
3. Export thermal energy via gold wire
4. For eutectic and Flip chip processes, thermal energy will be routed through the vias to the system board.
Generally, the LED particles (Die) are connected to a substrate (Substrate of LED Die) by gold wire, eutectic or flip chip to form an LED chip , and then the LED chip is fixed to the circuit of the system. System circuit board. Therefore, the possible heat dissipation path of the LED is to directly dissipate heat from the air (as shown in Figure 3, Route 1), or through the LED particle substrate to the system board to the atmosphere. The rate at which heat is dissipated from the system board to the atmosphere depends on the design of the entire luminaire or system.
Bright White Candles/velas/bougies .make of paraffin wax ,and stearic acid .
snow white and pure white color ,very bright quality holy brand candles .happy candles .OEM brand .
usually yellow color box packing ,red color box packing this packing more popular aslo the box can add shrink paper pack ,and 35g/pc 8x30box/ctn 36g /pc /
if any inquire pls tell me exact weight ,then I will offer you best price .welcome to visit my factory
and shipment in the 30days after get the depsoit .
Bright Candle,Bright Different Colors Candle,Bright Birthday Candle,Ultra Bright Led Candle
Shijiazhuang Zhongya Candle Co,. Ltd. , http://www.zycandlefactory.com