Power LED efficiency in relation to operating temperature

In this paper there are presented investigations regarding power IR LED efficiency in relation to operating temperature in order to define the reference values and conditions for using such devices for realizing long range proximity sensors, especially for applications in the automotive domain. The previous experiments done regarding the power LED used for infrared sources emphasize the optical power dependency to temperature. The new experiments were designed for measuring optical power and temperatures of LED heat sink and case, respectively of star and square type circuit boards (thermally conductive insulated metal substrate - IMS), at different points in the same time, for different values of LED driving current and various ambient temperatures, in order to make a correlation between LED efficiency and temperature. The results obtained and presented in this paper will be used further as references for designing an anticollision warning system with applications into automotive domain. Keywords: Power