Research On Single Event Flip Directional Fault Injection Technology For SRAM-type FPGA

Since its birth,compared with ASIC chips,the advantages of low cost and easy development of FPGA chips have made them rapidly applied in various engineering fields more and more widely.Among them,SRAM-based FPGA has become the mainstream of FPGA with its advantages of low cost,low power consumption and high performance,and has been widely used in the field of aerospace.However,due to the structural characteristics of SRAM-type FPGA,it is vulnerable to single event effects caused by space radiation environment,and then affect its functions.Therefore,in order to verify the sensitivity of the circuit system implemented on SRAM-based FPGA to the single event effect and evaluate its reliability,it is necessary to develop a special single event effect evaluation tool.This is the main content of this research.In this paper,Xilinx's SRAM-based FPGA Virtex 6 series development board is studied.According to its working principle and structure characteristics,the factors affecting the single event effect are analyzed.The types and characteristics of single event effect are discussed,and it is determined that single event overturn is the main cause of functional failure of the circuit system of FPGA.At the same time,the failure modes of each logic unit in the FPGA device after single event flip are analyzed,and the fault injection model of this subject is determined as a single event flip in the configuration memory of the device.In order to inject fault into SRAM-based FPGA,it is necessary to reconfigure the content of configuration memory.ICAP interface is chosen to implement this operation.After determining the fault injection model,a random fault injection platform composed of three modules,fault injection module,fault detection module and host computer,is established based on the reconfiguration operation of the content of the FPGA configuration memory by ICAP interface.Then,the fault injection platform is used to test the four reference combinational circuits,which verifies the validity of the fault injection platform.Direct reconfiguration of all bits of SRAM-based FPGA's configuration memory,on the one hand,due to the lack of pertinence of fault injection,it consumes more time;on the other hand,it may lead to errors in the whole fault injection platform and fail to work properly.Therefore,by using the essential bits technology of Xilinx Company,the configuration bits related to the user circuit are screened out to achieve more accurate and rapid fault location injection,so as to achieve more targeted single event effect evaluation of the user circuit.