Thermal Analysis of LED Packages based on Heat Pipe Heat Sink

The junction temperature of high-power light emitting diode(LED) has directly influence upon the life time and reliability of high power LED,so keeping the junction temperature of LED in the given range is a key issue being dealt with during device packing and application of high power LED.A new type structure flattened heat pipe cooling device for high power LED is brought forward.The thermal conductivity including junction temperature and thermal resistance of LED is studied in different heat dissipation modes under the same test condition.The obtained results indicate that the junction temperature of LED is about 52 ℃ and 83 ℃ for using the heat sink of flattened heat pipe and copper plate respectively, when the input power is 3 W,and correspondingly the total thermal resistance of LED system is 8.8 K/W and 19 K/W respectively.The heat dissipation property of flattened heat pipe is more excellent than the cooper plate’s in the condition of high input power.