Thermal Design of GaN-based High-power LED Module

Thermal management is the key issue for LED module design because luminous efficiency and lifetime of high-power GaN-based white LEDs are limited by heat dissipation.Temperature distribution of LED module under natural convection was simulated using computational fluid dynamics,and structure of fin for 5 W LED module was brought forward and optimized.Then,other key issues impacting heat dissipation were analyzed.The results show that junction temperature can be dramatically decreased by increasing thermal conductivity of attaching materials,and temperature characteristics of multi-chip package are superior to that of single-chip package both in junction temperature and chip temperature uniformity.The junction temperature of chip of the optimized module is about 60 ℃ under 5 W injection power.