基于供电网络传导耦合的FPGA电磁敏感特性分析

Electromagnetic susceptibility analysis of FPGA based on conducted coupling of power supply network

针对电磁干扰(EMI)导致电子系统关键功能单元行为失效或安全问题,研究基于供电网络传导耦合的核心可编程集成电路(IC)电磁敏感(EMS)特性。分析典型FPGA供电网络的拓扑结构及其EMI传导耦合机理,设计基于EMI直接功率注入法的敏感度测试平台,测试受试芯片供电网络EMI传导耦合时典型功能单元的EMS特性,获取输入输出端口(IO)、逻辑单元(LE)、内部锁相环电路(PLL)等功能单元的敏感度阈值,给出LE冗余设计对相应电路EMS特性的影响规律。结果表明,在10 MHz～1GHz干扰频率范围内,供电网络EMI敏感度由高到低依次为PLL,LE,IO,且IC地网络EMI敏感度高2～7dBmW,LE冗余设计能有效改善逻辑功能单元电磁敏感度。

Due to the problem of behavior failure or functional safety for electronic system caused by electromagnetic interference (EMI),the electromagnetic susceptibility characteristics of programmable integrated circuit (IC) based on the conducted coupling of power supply network are studied.The topology structure of power supply network and the EMI conducted coupling mechanism of typical FPGA are analyzed,and the immunity test platform based on EMI direct power injection method is designed.The electromagnetic susceptibility feature of typical functional units are measured when the EMI is conducted to the power supply network of the IC under test,then the susceptibility thresholds of internal phase-locked loop (PLL) circuit,logic element (LE) and input/output port is obtained and the influence law of LE redundancy design on EMS characteristic of corresponding circuits is given.The results show that,for interference frequencies in the range of 10 MHz-1 GHz,functional units with EMI susceptibility from high to low are PLL,LE and IO,and the EMI susceptibility of IC ground network is 2-7 dBmW higher.LE redundancy design can effectively improve the EMS of logical functional units.