Thermal design and experimental validation of a dual-CCT chip-on-board LED module

Efficient heat dissipation is essential for maintaining reliability and luminous stability in high-power light-emitting diodes (LEDs). This study presents the thermal design, numerical modeling, and experimental validation of a dual-correlated color temperature (CCT) Chip-on-Board (COB) LED module. The proposed configuration integrates two spectral branches (warm and white) on a single metal-core printed circuit board (MCPCB), enabling selectable color temperature without increasing package size. A finite-element model was developed in the Free software ELMER GUI to predict the temperature field within the LED substrate and to evaluate the impact of die arrangement on heat spreading. The simulations were validated through thermocouple measurements and infrared thermography, achieving strong agreement with a root mean square error of 2.7 °C and a mean absolute percentage error of 4.3%. The results showed maximum substrate temperatures of 70.6 °C and 70.2 °C for single-branch operation and 107 °C under combined operation. Photometric characterization confirmed stable CCT values around 3200 K (warm), 4000 K (white), and 4800 K (dual), with luminous efficacies between 50.8 and 69.2 lm/W. The findings demonstrate that integrating dual-CCT emission within a monolithic COB structure is thermally feasible and photometrically stable, providing a practical approach for energy-efficient, tunable solid-state lighting systems.