Evaluation of junction temperature of LED package as a function of input current and ambient temperature

Thermal management of high-power (HP) light-emitting diodes (LEDs) is a crucial area of research and development. LED junction temperature (Tj) is a critical parameter that directly affects its entire performance. LED thermal, photometric, and electrical parameters depend on Tj. It is important to estimate Tj to improve the LED performance during the operation time. In this manuscript, the estimation of LED Tj at a given ambient temperature (Ta) and input current (If) is reported. The LED thermal resistance (Rth), forward voltage (Vf), and wall-plug efficiency (ηw) are considered in this estimation. Combination of TeraLED and T3Ster systems are used to obtain thermal and optical test reports for the LED at various If and Ta. Good agreements between the calculated and measured values confirm the proposed method.