Mixed-simulation Of Single Event Effect For Multi-chip Structure System

With the popularization of system in package(SiP)technology in the aerospace field,more and more on-board computers and other aerospace equipment are equipped with multichip structure systems encapsulated by SiP technology.However,due to the increase of the single event effect caused by the reduction of the characteristic size of the transistor,the reliability of aerospace electronic equipment has become the most important research in the aerospace field.Benefiting from the advantages of low cost,high efficiency,and strong flexibility,computer simulation technology can simulate the process of high-energy particles incident on the chip with higher accuracy.It is a powerful method to verify the reliability of chip radiation which compared with the space radiation experiments and ground radiation experiments with more restricted factors.It is of great significance for the chip’s antiradiation hardening design and radiation resistance performance evaluation.This paper focuses on the single event effect in the radiation effects.Based on the evaluation of the single event effect resistance ability of aerospace equipment,the research of the single event effect simulation method for the multi-chip structure system packaged by SiP technology is carried out.It aims to improve the shortcomings of the existing circuitlevel simulation by using mixed-simulation method.At the same time,this paper completes the evaluation of the single event effect ability of the target circuit.The main research contents and research results of this paper are as follows:(1)A mixed-circuit model of the SiP system with the Leon2 processor as the core is built.According to the SiP technology package cavity of the on-board computer provided by a cooperative unit,retaining its core part,and establishing the SPICE circuit model.The circuit model is composed of a Leon2 processor and three SRAM chips.Then remodeling the circuit model by the mixed-simulation method provided in the Fine Sim user manual.The mixed-circuit model of the SiP system with the Leon2 processor as the core is obtained,which is as the example in this paper.(2)The related research on the mixed-simulation method of VCS combined with Fine Sim is completed.Among them,the single event transient current source model is obtained in the form of PWL,the model is written into the circuit in the form of Perl script,and the research of the fault injection method is completed.At the same time,the data measurement and result comparison in the simulation are realized through Perl and Shell script.And a fast division method for the mixed-circuit modules is proposed for the mixedsimulation,which effectively improves the simulation efficiency.(3)The sensitivity analysis of the module-level single event effect of the SiP system is completed.Based on the built-up mixed-circuit model and the proposed mixed-simulation method,a simulation scheme of the SiP system module-level single event sensitivity is proposed.The simulation uses the program instructions of the third-order matrix multiplication.The simulation analysis is carried out for the integer processing unit,register file,cache,AMBA bus controller,storage controller,instruction SRAM and data SRAM in the target SiP system.It is found that the system soft error rate of data SRAM is 5.57%,which is much higher than the rest of the system.It needs to be considered in the design of single event effect resistance reinforcement.At the same time,relevant targeted simulations are carried out on the chip stacking in the SiP package.It is found,in general,the stacking of chips aggravate the probability of system errors,thereby increasing the system soft error rate.(4)The sensitivity analysis of the whole circuit single event effect of the SiP system is completed.Based on the module-level simulation scheme,an area equivalent analysis method is proposed to further realize the mixed-simulation of the whole circuit.The soft error rate of the target SiP system is 6.03%.At the same time,the same simulation settings are used to complete the SPICE simulation of the target SiP system.It is found that the mixed-simulation obtains the characterization results of the single event effect almost consistent with the SPICE simulation.In terms of time cost,the mixed-simulation is nearly5 times faster than SPICE simulation,which greatly saves simulation time.Finally,according to the simulation results,aiming to data SRAM,which is the most sensitive module in the system,a three-mode redundancy reinforcement method is proposed.It provides a theoretical basis for the design of the single event effect resistance reinforcement in target SiP system.