The analysis of the thermal resistance structure of LEDs by measuring its transient temperature variation

In order to establish a thermal resistance structure diagram for the light-emitting diode (LED), a thermostat state test platform with a T.E.C.-controlled LED board temperature was established. The Transient Thermal Resistance Structure Analysis (TTRS Analysis) software designed and developed for this study was used to analyze its internal structure in order to establish the overall thermal resistance structure of the LED. The study experimented on two different groups of 1W LEDs to measure their K_factor coefficients and transient temperature changes using the same thermal interface material but four different kinds of thickness when doing the total thermal resistance response tests. The experimental results show the error values were kept to within 10%, indicating extremely high repeatability of the measurement results. In this study, we used three different thermal interface materials to do the total thermal resistance response test. The three repeatability tests for TC-5121 showed the errors are less than 4%; and errors are less than 1% for both X-23-7783D and X-23-7762. During the three repetitive measurements found high repeatability of the measurement results to verify the reproducibility and stability of the measurement system.