Thermal analysis of high power LEDs

Abstract

Solid-state lighting is a technology which uses semiconductor materials to convert electricity into light. In the earlier discovery, the LEDs emitted low-intensity light with limited colour and were mainly used as signal components or indicators in electrical system. In order to increase the brightness, intensity and luminous flux of LEDs, improvements in materials and crystal-growth techniques were incorporated in the production of high power LEDs, which have improved reliability and efficiency of the devices. But due to the power increase, thermal related problems were encountered during the design and applications. So, the thermal analysis of high power LEDs became an essential factor for designing, reliable and efficient LEDs. In this paper, we used TRM software to study the heat dissipation across the various components of an LED circuit when mounted on different types of substrates. Different PCB materials were used for the simulations, FR4 and diamond. The use of a diamond PCB decreases the operating temperature of the components without requiring additional heatsinks. This results show the importance of PCB materials with high thermal conductivity in the case where the size and volume of the electronic boards is a constraint.