Study of Degradation in Switching Mode Power Supply Based on the Theory of PoF

Switching Mode Power Supply (SMPS) is the most important source for electronic or electrical equipments, therefore its reliability acts as a fatal factor impacting on these devices´ lifetime. Applications shows that aluminum electrolytic capacitors, and some power components like diodes and MOSFETs, all of which turn out to be key factors to SMPS´ lifetime, are of higher failure rates in SMPS. In fact, the failure of electronic products is a gradual course, which is usually resulted from the degradation of separate electronic components. In this paper, a specific SMPS system is regarded as the research object and the experimental study of its degradation is discussed. To study the SMPS system´s degradation owning to these critical components, such as power MOSFETs, diodes and aluminum electrolytic capacitors, the components´ performance parameters which can reflect their degradation need monitoring. In order the acquire remarkable effects, accelerated aging test is adopted in this paper. The study of SMPS´ degradation on basis of the theory of PoF (Physics of Failure) in this paper is meaningful to the reliability research of SMPS and provides an approach for the prognostics of its RUL (remaining useful life).