@inbook{50a783560bd749f18867d8cbe96c45e4,
title = "Reliability Prediction of Integrated LED Lamps with Electrolytic Capacitor-Less LED Drivers",
abstract = "This chapter investigates the reliability of the integrated LED lamps with electrolytic capacitor-less LED drivers. Firstly, the impact of the interaction between the degradations of the LED light source and the driver on the lumen depreciation is studied. The electronic-thermal simulation was carried out to obtain the history of temperatures of LED and driver, the driver{\textquoteright}s output current, and the luminous flux considering the variations of temperature and current throughout the operation life. It is found that the ultimate lamp{\textquoteright}s lifetime is significantly less than the individual lifetimes of the preselected LED and driver. It is concluded that it is necessary to apply the electronic-thermal simulations to predict the lifetime of LED lamps when driver{\textquoteright}s lifetime is comparable to the LED{\textquoteright}s lifetime. Secondly, this chapter focuses on predicting the catastrophic failure of an electrolytic capacitor-free LED driver during the lumen depreciation process. Electronic-thermal simulations are utilized to obtain the lamp{\textquoteright}s dynamic history of temperature and electrical current for two distinct modes: constant current mode (CCM) and the constant optical output (CLO) mode, respectively. A fault tree method is applied to calculate the system{\textquoteright}s MTTF, and the LED{\textquoteright}s lifetime also is calculated. The CLO mode increases the LED{\textquoteright}s current exponentially to maintain the constant light output. As a result, junction temperatures of LEDs, MOSFET, and diode rise significantly, leading a shorter lifetime and MTTF. Compare with the current of the MOSFET, the increased junction temperature has larger effects on the failure rate. The MOSFET contributes more to the driver{\textquoteright}s failure rate than the diode. For the CCM mode, junction temperatures increase slightly and have a little shorter lifetime and MTTF.",
keywords = "Lifetime prediction, Mean Time To Failure (MTTF) , Maximum likelihood estimation, LED driver, Reliability , Electronic-thermal simulation",
author = "B Sun and Xuejun Fan and {van Driel}, {Willem Dirk} and Zhang, {Guo Qi}",
year = "2018",
doi = "10.1007/978-3-319-58175-0_16",
language = "English",
isbn = "978-3-319-58174-3",
series = "Solid State Lighting Technology and Application Series",
publisher = "Springer",
pages = "455--486",
editor = "{van Driel}, {Willem Dirk } and Fan, {Xuejun } and { Zhang}, {Guo Qi }",
booktitle = "Solid State Lighting Reliability Part 2",
edition = "1",
}