Investigation on thermal characterization of low power SMD LED mounted on different substrate packages

Low power surface-mounted device light emitting diode (SMD LED) is of high interest in research and development due to its portability and miniature size. However, high thermal resistance of low power SMD LED is a major concern due to lack of metal heat spreader. The evaluation of junction temperature and thermal resistance is important in understanding the thermal management and thermal reliability of low power SMD LEDs. In this paper, thermal parameters of low power SMD LED are determined. LED is mounted on different substrate packages which are FR4, 2W and 5W aluminum packages. Thermal parameters of LED are measured using Thermal Transient Tester (T3ster) at 50 and 100 mA. It is found that 5W aluminum package shows lower thermal resistance and junction temperature compared to the other two substrate packages. To validate the experiment, modeling and simulation using FloEFD is developed by considering geometrical model of the substrate packages.