用于双陀螺组合的DC/DC模块失效分析  

Failure Analysis of DC/DC Module for Double-Gyro Combination

作　　者：孔泽斌 廉鹏飞 张辉[1] 杨亮亮 姬青 Kong Zebin;Lian Pengfei;Zhang Hui;Yang Liangliang;Ji Qing(No.808 Institute,Shanghai Academy of Spaceflight Technology,Shanghai 201109,China)

机构地区：[1]上海航天技术研究院第808研究所

出　　处：《半导体技术》2018年第10期795-800,共6页Semiconductor Technology

基　　金：XXX领域预先研究项目(050401)

摘　　要：针对应用在双陀螺组合中的DC/DC模块输入级VDMOS内引线熔断、输出级整流二极管发生短路的问题进行了失效分析。通过分析可知,DC/DC模块失效是由于其输出端整流二极管击穿短路,导致输入端电流异常增大,致使VDMOS的源极内引线过流熔断。通过对故障树进行试验和排查,整流二极管击穿是由于DC/DC模块瞬时启动重载使模块内部功率调节时产生个别幅度较高的电压毛刺;并且两路陀螺组合同时启动时,电源母线负载较大致使输入端的电压波动较大;加之整流二极管能量耐受力不够,三方面的原因共同造成DC/DC模块整流二极管被电压击穿,从而引发DC/DC模块失效。此外,根据失效原因提出了在DC/DC模块输出整流二极管两端并联RC吸收网络的改进措施。Failure analysis of DC/DC module used in double-gyro combination was carried out to solve the problems of internal lead fusing in input stage of VDMOS and rectifier diode short circuit in output stage. Based on analysis,the reasons of the DC/DC module failure was the breakdown of the output rectifier diode,which lead to the abnormal increase of the input current and the over-current fuse of the source interconnection of the VDMOS. It was shown by fault tree and experiments that three reasons were responsible for the breakdown of the rectifier diode. Firstly,with the startup heavy load of the DC/DC module,there were some high-amplitude voltage burrs resulted from internal power regulation. Secondly,when the two gyros were combined to start at the same time,heavy loads of the power bus increased the fluctuation of the input voltage. Finally,the permissible power of the rectifier diode was not enough. The three reasons caused the breakdown of the rectifier diode,resulting in the failure of the DC/DC module.In addition,the improvement measure of RC absorption network that was added in parallel with the output rectifier diode of DC/DC module was presented according to the failure reason.

关 键 词：DC/DC模块 整流二极管 失效分析 启动重载 能量耐受力 

分 类 号：TN792[电子电信—电路与系统]