Reliability and lifetime prediction of LED drivers

LED drivers are critical components in LED luminaires, which power and control LEDs to deliver light as desired. They are also the weakest links inside LED luminaires so that their lifetime can greatly affect the useful life of the whole system. Therefore, the study on the reliability and lifetime of LED drivers is of great theoretical significance and practical value. This paper presented two methods to predict the reliability and lifetime of LED drivers. One method is an improved part stress analysis method based on MIL-HDBK-217F without the need of conducting reliability testing, the other is an experiment-based method using accelerated life testing. The paper also applied both of the methods to predict the lifetime of the same quasi-flyback LED driver. The temperature-dependent lifetime results are demonstrated in the paper, and a good match between the two sets of results was observed. This indicates the improved part stress analysis method presented in this work is an effective way to predict the reliability and lifetime of LED drivers. Also, the method is especially suitable for the reliability and lifetime research in the course of designing and developing LED luminaires because it does not require reliability testing which is typical expensive and time-consuming.