A probabilistic physics-of-failure reliability assessment approach for integrated LED lamps

This work studies the effect of randomness of LED's lumen depreciation on reliability of the entire LED lamp. An integrated LED light bulb is selected as carrier of the proposed method. A PoF based lumen depreciation model and electronic-thermal simulations are introduced for reliability prediction. The normal distribution is used to describe the statistical distribution of LEDs. The probabilities of the driver's catastrophic failures and lumen can then be obtained by Monte Carlo simulations by considering the increase of lamp's temperature. The effect of the lumen depreciation to the entire lamp is studied with two scenarios: constant light mode and constant current mode.