Physics-of-failure-based method of reliability modeling for led switch driver with failure correlation

Now with the application of high power LED more and more widely, the reliability of LED has gradually attracted more and more attentions. As an important part of the LED lighting system, the LED driver has a significant impact on the reliability of the system. In this paper, Physics-of-Failure-based (POF) method of reliability modeling was developed for LED driver by considering the failure correlation. Firstly, the failure modes of LED driver are analyzed and the corresponding failure physical models are found. Secondly, the relationship between the failure modes is characterized by taking the advantage of Copula in describing correlation. Then, a uniform failure physical model is obtained, and a reliability model of LED driver is established. Finally, a case study is illustrated the effective of the proposed model. The final result shows that the proposed model which considered the failure correlation can be more accurate in predicting the reliability of LED drives relative to the conventional method of considering single dimension failure mode.