基于RRAM的DMA模式的测试系统设计

发布时间：2018-08-16 12:59

【摘要】：随着经济发展和技术的进步,非易失性存储器(NVM)的地位变得越来越重要。FLASH作为NVM的代表,广泛应用于各领域。但是受到最小工艺尺寸的限制,FLASH的发展前景不容乐观。由于具有相当可观的微缩化前景,密度高和速度快等特点,阻变存储器(RRAM)极有可能取代FLASH,成为下一代主流NVM。目前RRAM流片后,主要使用商用测试机对其作测试。但是,商用测试机存在操作复杂,费用昂贵,实用性差等问题,使得RRAM从设计到量产的周期大大延长。一般情况下,RRA。M有DMA(Direct Memory Access)模式和用户模式两种。DMA模式即直接存储器访问,是专用于测试RRAM的模式。用户模式,即用户实际使用RRAM进行数据读写。基于上述考虑,本课题开展RRAM的DMA模式的专用测试系统的设计工作,拟解决其测试问题。课题研制的测试系统具有实用性强,操作方便,价格低廉和性能可靠等特点,可以大大降低RRAM研究单位的测试成本,加快RRAM的研发。本文首先介绍了商用测试机的国内外研究现状,讨论了 RRAM测试面临的技术问题。其次介绍了 RRAM的基本原理,及其在DMA模式下的测试方法,在此基础上定义了 ATE通信协议与测试流程,然后设计了一款针对RRAM的DMA模式的测试系统。本测试系统有30个激励通道,1个接收通道,拥有直流参数测量模块,可以对RRAM单元进行forming,reset和set等基本测试。它主要由上位机,FPGA,四通道参数测量单元AD5522和高精度的模数转换器AD7685等组成。文章详细讲解了测试系统的核心部分——FPGA的设计,在ATE通信协议与测试流程的基础上,提出FPGA架构,并作详细的模块划分,然后对各模块(通信模块、发送模块、系统控制模块、AD5522控制模块和AD7685控制模块)进行详细设计。并利用ISE和Modelsim软件完成了各模块的verilog代码设计与仿真验证。接着,对测试系统的硬件进行调试,验证了其测量功能。最后,对全文进行了总结,并给出了未来进一步研究方向。
[Abstract]:With the development of economy and technology, the status of non-volatile memory (NVM) becomes more and more important. Flash, as the representative of NVM, is widely used in various fields. However, the development prospect of flash is not optimistic due to the limitation of minimum process size. Because of its considerable microshrinkage prospect, high density and high speed, resistive memory (RRAM) is likely to replace flash and become the mainstream of the next generation. At present, after RRAM streaming, commercial testing machine is mainly used to test it. However, the problems of complex operation, high cost and poor practicability of commercial test machine make the cycle of RRAM from design to mass production be extended greatly. In general, RRA.M has DMA (Direct Memory Access) mode and user mode. User mode, that is, the user actually uses RRAM to read and write data. Based on the above considerations, the design of a special test system for DMA mode of RRAM is carried out, and the test problem is solved. The test system developed in this paper has the advantages of strong practicability, convenient operation, low price and reliable performance. It can greatly reduce the testing cost of RRAM research units and speed up the research and development of RRAM. This paper first introduces the research status of commercial test machines at home and abroad, and discusses the technical problems of RRAM testing. Secondly, this paper introduces the basic principle of RRAM and its testing method in DMA mode, then defines the ATE communication protocol and test flow, and then designs a test system for DMA mode of RRAM. The system has 30 excitation channels and one receiving channel, and has DC parameter measurement module, which can be used for basic testing of RRAM unit such as formingreset and set. It is mainly composed of PC FPGA, four-channel parameter measurement unit (AD5522) and high precision A / D converter (AD7685). In this paper, the design of the core part of the test system is explained in detail. On the basis of ATE communication protocol and test flow, the FPGA architecture is put forward, and the detailed module partition is made, and then every module (communication module, sending module) is given. The system control module, AD5522 control module and AD7685 control module, are designed in detail. The verilog code design and simulation of each module are completed by using ISE and Modelsim software. Then, the hardware of the test system is debugged and its measuring function is verified. Finally, the paper summarizes the full text and gives the future research direction.
【学位授予单位】：安徽大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP333

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