Influence of the Cooling System on Characteristics of Power LEDs in COB Packages

K. Górecki, P. Ptak, D. Płokarz (Gdynia Maritime Univ., Poland)

The paper presents the results of measurements of the characteristics of selected power LEDs mounted in COB packages. The operation of this class of semiconductor devices without any additional cooling system, with a classic aluminium heat-sink and with a liquid cooling system with a heat exchanger were considered. The structures of the tested diodes and the measured current-voltage characteristics of the tested devices operating in the forward and reverse modes, the dependence of the luminous flux and thermal resistance on the forward current and the waveforms of the illuminance of the emitted light were presented. The obtained measurements results were discussed. Particularly, an influence of self-heating phenomena on the obtained characteristics was considered.