【摘要】 IGBT栅极电压的米勒平台时延与结温有着密切的关系,是IGBT失效的一种重要表征量,因此精确测量IGBT栅极电压米勒时延对于IGBT模块的失效监测有着重要的意义,基于此本文设计了完整的米勒时延测量系统。首先设计实现了栅极电压米勒平台的微分提取电路,将米勒平台转换为数字双脉冲,然后研究了利用FPGA内部特殊结构——进位连线组成时间内插延迟链,实现了高精度的时间内插测量。经实验验证,本文所设计的系统能够实现米勒时延亚纳秒级测量精度,为进一步定量探索IGBT模块失效与米勒时延的关系提供了保障。更多还原

【Abstract】 The Miller plateau of IGBT gate voltage,as an important precursor of failure monitoring,has a close relationship with junction temperature. As a result,the accurate measure of time delay of Miller plateau in gate voltage is vital to the online detecting of IGBT failure. A complete measurement system has been set up in this paper.Firstly,the Miller plateau was converted to double pulse by using a differential and comparator circuit based on the three-stage feature of gate voltage. Secondly,the time interval between the double pulse was measured accurately based on carry delay chain in FPGA. In this paper,a directly instantiated method of logic element( LE) was adopted to achieve a carry chain. The error caused by the metastable state problem and the key paths time delay problem were analyzed. The measurement system has achieved 500 ps precision which is verified by simulation and experiments.更多还原