LAUSR

Abstract Advantages of LEDs include high brightness, reliability, low power consumption and a long life. These advantages have made LEDs feasible in a wide range of automotive lamps applications. However, LEDs are semiconductor p-n junction devices and their electrical and optical properties are temperature dependent. Especially for automotive lamp applications, the increased temperature influences the luminous flux droops and thus the color of the light changes related to wavelength shifting. In this study, it is intended to conduct an experiment to control the junction temperature of automotive LED lamps. To control the junction temperature of LED, the current feed forward strategy was proposed. Furthermore, the change in luminous flux according to junction temperature control was investigated. For the experiment, LED chip (CH3535E-UY3501L-AM, from Everlight co.) was used. The thermocouple (Fluke-116) measures the temperature at the solder point to obtain the junction temperature using the heat transfer equation. For measuring the optical properties, it was performed using the T3Ster TeraLED system. The experimental results show, the temperature control based on the current feed forward method is stable with the performance in the overall control inputs/outputs.