Accelerated lifetime test for isolated components in linear drivers of high-voltage LED system

This paper proposes an isolated component accelerated lifetime testing of high-voltage SSL driver. In this method, the most critical component(s) will be isolated from the rest, and critical stress will be applied to these components to estimate the lifetime. Although circuit modification is unavoidable, this testing method can minimize failure interactions between components and testing duration for the system. Thus, compared to the conventional accelerated testing method, this method could achieve shorter test duration. In the configuration of high-voltage LED, the electrolytic capacitors have been selected from the linear driver configuration. As one of most significant failure mechanisms, the effects of high temperature degradation of electrolytic capacitors to the entire system were investigated in this test. To quantify these effects, the changes in luminous flux and power consumption over time were measured. By analysis of all these output data, the relationship between the system's outputs and temperature of electrolytic capacitor can be found. For the high-voltage LED system, this relationship is a required condition for the accurate system reliability prediction.