In comparison to traditional life testing, even under accelerated conditions, the degradation modelling yields more useful data. For light emitting diode modules (LEDM), where failures are rare or take a long time to occur, this is the only effective approach. A bivariate constant stress accelerated degradation test model has been proposed to high power chip-on-board LEDM. In order to verify the theoretical considerations which are being made, a special measurement stand was prepared. Tests are accomplished for one stress factor (temperature or electrical current) as well as for two stress factors (temperature and electrical current). The purpose of experiment was to find how much the temperature activated degradation was related with current stress.

Full text: IJEIR_1215_Final.pdf