Compact modeling of electrical, thermal and optical LED behavior

TLDR

A new nonlinear compact LED model for SPICE/ADS is presented to predict voltage‑current characteristics, optical power, and junction temperature under dc, small‑signal, and pulsed conditions. The model incorporates electrothermal and optical feedback, with a step‑by‑step parameter extraction that decouples electrical, thermal, and optical domains and robustly determines series resistance and junction‑to‑ambient thermal resistance. Validation shows the model accurately matches measured electrical and optical data.

Abstract

A new nonlinear compact LED model for circuit simulators like SPICE or ADS is presented. The model is useful to predict the LED's voltage-current characteristics, total optical power and pn-junction temperature under dc, small-signal and pulsed operating conditions. Electrothermal and optical feedback effects are considered. A step by step model parameter extraction procedure is presented by carefully decoupling the electrical, the thermal and the optical domain. New and robust methods to extract the LED's series resistance and the junction to ambient thermal resistance are presented. The model is validated through electrical and optical measurements compared to the simulations.