Thermal Simulation Research Of LED Power Based On COB Packaging Structure

With the continuous development and progress of science and technology,the development of the human in the lighting field is unprecedented prosperous.From the end of the last century, with the development of semiconductortechnology matures, LED lighting in environmental protection, energy saving,improving lighting quality and efficiency has shown great advantages, and itsapplication is more and more widely. LED device package as a middle link of thesemiconductor lighting industry chain, the function of packaging is to provideadequate protection to the chip, prevent the chip failure because of the long-termexposure or mechanical damage in the air, in order to improve the stability of thechip.Good packaging can let the LED have the better light emitting efficiencyand radiation environment, and improve the service life of the LED. In this paper,use the joint simulation by Pro/E and finite element analysis software ANSYSsimulation, we take the thermal simulation and thermal analysis for the powerLED SMD and COB which the two kinds of packaging structure in the themarket that is generally and more mature packing technology. The main work asfollows.First of all, this paper starts from the thermal characteristics of power LED,do the research deeply on the axial symmetric power type LED encapsulationstructure, discusses in detail the research purpose and significance of this thesisand the future development trend. The heat transfer, heat conduction and thermalmodel was discussed in theory. The power type LED highly integrated sealwithout affecting the package structure is put forward on the premise with largecurrent test junction temperature method, provide support to obtain accurateexperimental data.Secondly, with the unceasing development of new packaging technology of power LED, introduced SMD and COB which is two kinds of packagingstructure. This paper selects two kinds of structure of SMD and COB packagepower LED samples as examples. Using high current test temperature mothod onLED samples of two kinds of node package structure to do the test dataacquisition and analysis, and compared with the ANSYS simulation results, toverify the accuracy of ANSYS software to establish the model and analysis.Finally, this paper uses the joint by Pro/E and finite element analysissoftware ANSYS for COB packaging structure according to the differenttransmission path of three different forms of simulation analysis, and then makesa quantitative analysis of growth through the radiator.For power type LEDproducts, with the reducing of the heat conduction number through the verticaldirection, the fewer places for the conduction path through, then correspondingcooling effect is better, The radiator rise COB-A187.5%and COB-B32.5%respectively, can achieve the cooling effect is equivalent to COB-C, so we canchange the conduction path to change the cooling effect, not only low cost, morepractical.