Electric and thermal transient effects in high power optical devices

In case of opto-electronic devices the power applied on the device leaves in a parallel heat and light transport. For this reason the interpretation of R_th is not obvious. By studying electrical and thermal transients in high power LEDs this paper proposes a multi-domain "compact" model suitable for correct simulation of single devices as well as LED arrays in a board-level simulation environment. The thermal part of the model has been identified from structure functions extracted from measured thermal transients. Several measurements were carried out in a combined photometric/thermal measurement setup, which is proposed for the characterization of power LEDs. Transient simulation results compared to measured transients are also presented.