Reliability Analysis Of MOS At Different Temperatures

Solid State Power Controller(SSPC) is an electronic component which owns the switching function of relays and circuit protection function of circuit breakers. It’s the key device to control ON state and OFF state of loads. The core component of SSPC is VDMOS FET, which is a kind of high-reliability and long-lifetime products. This paper based on real test degradation data, selected an appropriate characteristic quantity which described the process of degradation and discussed the degradation of reliability of MOS.Life data analysis is one of the reliability measures. With the widespread use of high-reliability and long-life products, research on the analysis of life data and the corresponding improvement measures is becoming more and more important. Statistics analysis of life data is a method to make a quantitative understanding of lifetime characteristics. Through the analysis of life data, the paper presented the lifetime distribution type, parameter estimation and the reliability function.In order to analysis the reliability of MOS in the different temperatures, the paper’s main analysis is as follows:First of all, the research status at home and abroad on the reliability of MOS is introduced, and point out the significance of this kind of issue.Secondly, based on the degradation data at the temperature of 150 degree, the paper used the Least Square Estimation(LSE) and the Second-order Least Square Estimation(SLSE) to estimate the regression function of the degradation data of MOS. When the chosen characteristics value changes to 120% of the initial value, MOS will be regarded as broken. It’s easy to get the false lifetime of different MOSs. Besides this, based on the failure data of other temperatures of 180 degree, 200 degree and 230 degree, the parameter estimation can be given. And the reliability functions at different temperatures was presented.Thirdly, with the false lifetime data and failure data, the paper treated Weibull distribution as lifetime distribution. The paper gave the shape parameters and scale parameters of Weibull distribution at different temperatures. Lifetime distribution is verified reasonable by the hypothesis testing methods.Finally, the paper gave the characteristics of lifetime of the MOS at other temperatures, for example 35 degree, 45 degree,55 degree, 65 degree, 75 degree, 100 degree, 110 degree and 130 degree.