Research On Self-repairing Design Of FPGA System Based On Cell Array Structure

Commercial SRAM-based FPGAs have the characteristics of strong performance,re-programmability,high flexibility and low power consumption,which have great application value in the field of aerospace.In this paper,the research background is that commercial SRAM-based FPGAs are susceptible to single event effects,which produce various kinds of faults under the strong radiation environment of space.Aiming at improving the reliability and utilization of hardware resources of commercial SRAM-based FPGAs,a self-repairing design method of FPGA systems based on cell array structure is studied.The design of function module and self-repairing control module are improved baesd on the existing self-repairing structure of FPGA application systems.The main research work of the paper is as follows:(1)Based on the current research status of self-repairing structure of FPGA application systems,aiming at the problem of low utilization of hardware resources of function modules due to the cold backup self-repairing methods of replacement between reconfigurable areas,a cold backup self-repairing methods of replacement in reconfigurable areas is studied,which reconstructs and repairs the different areas of function cells by using configuration information of the same function;(2)In order to improve the reliability of the self-repairing control module,in view of the current situation,where the fault-tolerant methods of the self-repairing control module are mainly using the Triple Modular Redundancy of processors,a self-repairing control module based on the distributed self-control cellular array structure is studied.Control cells in the self-repairing control module can make autonomous decisions on the fault reapiring of the function module,and control cells can repair themselves by removing the faults in them;(3)Aiming at the self-repairing circuit structure of the FPGA system in this paper,the working principles of the self-repairing strategies are studied.The function module adopts a self-repairing strategy of classification with soft and hard faults to improve the system reliability in the space environment with different proportions of soft faults.A control cell based on the self-repairing strategy of classification with soft and hard faults is designed.The self-repairing control module uses a self-repairing strategy of removal and replacement with control cells to improve the system reliability under the same conditions of hardware resource consumption.An auxiliary rewiring module based on the self-repairing strategy of removal and replacement with control cells is designed;(4)According to the structure and self-repairing strategies of the function module and self-repairing control module,the system is designed,implemented and verified.The System is designed with an eight-bits pipeline adder as the verification object to verify the correctness of the self-repairing function,and compared with the commonly used system self-repairing design methods to prove that self-repairing design method of the system in this paper can effectively improve the reliability of the system of SRAM-based FPGAs.Finally,the performance analysis of the self-repairing structure in this paper is performed from three aspects with hardware resource consumption,amounts of configuration information and time consumption,which illustrates the feasibility and efficiency of the self-repairing design method of FPGA system based on cell array structure.