Fast thermal resistance measurement of high brightness LED

The measurement of device thermal resistance is a common approach to junction temperature determination given a set of environmental conditions and the device power dissipation. This paper introduces a novel instrument that can measure the thermal resistance of high brightness LED quickly using electrical test method (ETM). According to the international JEDEC standard, the instrument uses the LED itself as a temperature sensor. DAQ6221mx PCI data acquiring card was used to build the system and the related software is Labview. Various measurements are carried out by choosing different samples, and the result shows it takes about 10 seconds to get the thermal resistance of the LED under the condition the K factor is known.