| In today’s increasingly innovative technology,electronic systems are widely used in the fields of aerospace,military equipment,information and communication.As a very important electronic device in electronic systems,the electromagnetic stability of memory in harsh electromagnetic environment directly determines whether the electronic system can work normally.High temperature and high pressure,complex electromagnetic environment,particle irradiation can become important factors affecting the stable operation of memory.When the traditional CMOS process memory can not meet the needs of special application environment,new memories are born.Therefore,the research on the EMC characteristics of new memories is very important to improve the EMC and reliability of the whole electronic system.This paper investigates the electromagnetic sensitivity of a Magnetic Random-Access Memory(MRAM)chip memory module,and through theoretical analysis and experimental verification,the electromagnetic compatibility characteristics of the memory module when storing different contents and subject to different interference.Random-Access Memory(SRAM)chips and MRAM for comparison and analysis.Finally,a new circuit structure is proposed based on the theoretical analysis and test data,which has stronger anti-interference characteristics than the original structure.The specific work is as follows.Firstly,the background and significance of IC EMC research,as well as the storage principle and logic of MRAM memory chips are described,and the failure mechanism analysis of magnetic tunnel junction storage particles as well as MOSFETs is carried out.Secondly,the failure mechanism of electromagnetic sensitivity of MRAM memory module is studied.The electromagnetic characteristics of the magnetic tunnel junction as well as the peripheral circuits are analyzed according to the principle of the chip modular layout.Experiments on the electromagnetic susceptibility of the memory module are carried out according to IEC 62132 and IEC 61967 test standards,and electromagnetic susceptibility tests are completed,and two different SRAMs are selected to compare with MRAMs for susceptibility studies.The study shows that MRAM,a new type of memory,shows different patterns in the radiation emission results compared to SRAM.In terms of electromagnetic sensitivity,it possesses a higher immunity compared to SRAM.Finally,it is found through experimental results that the electromagnetic sensitivity of the readout circuit is one of the key factors affecting the electromagnetic compatibility of MRAM memory.Since the sensitive amplifier is the core structure of the readout circuit,enhancing the electromagnetic sensitivity of the sensitive amplifier can help improve the EMC characteristics of the chip.In this paper,a new circuit structure is proposed by analyzing the read logic of the sensitive amplifier and the potential bias when disturbed,which effectively reduces the electromagnetic sensitivity of the sensitive amplifier and verifies the correctness of the circuit logic by simulation.This structure is an important guideline for improving the immunity of MRAM. |
