Three kinds of high-power LED packing methods based on the structure and the character of COB were presented,the first method was that the LED chip was directly boned to the aluminum radiators(COB—III),the 2nd and 3rd methods were that LED chips were bonded on aluminum pad and PCB board(COB—II,COB—I),respectively.The thermal characteristics of the three COB structures were simulated by FEM analysis and tested.The results show that when the ambient temperature is 30 ℃,the LED junction temperatures of COB—II ...