一种基于大容量数据记录仪的坏块管理设计

总结了目前基于FPGA的NAND Flash芯片数据记录仪常用的坏块处理方法,提出了一种基于FPGA的大容量数据记录仪的坏块管理方案.该方案利用FPGA内部RAM空间建立坏块地址信息存储区,通过坏块查询模块来查询存储区中的坏块信息,来确定当前存储块是否为坏块,若是坏块则跳过,从而避免对坏块的操作,实现了对Flash存储空间的有效管理.该方案只占用FPGA较少的内存资源,在大容量数据记录仪的坏块管理方面具有较大的优势.仿真分析表明,该方案可行,并取得了预期结果.     

大容量存储中NAND Flash坏块的管理方法

在当今数字时代,NAND Flash由于其非易失性和读写速度快等原因而在大容量存储中的应用越来越广。但由于Flash中不可避免的会出现坏块,对大容量存储的速度与精度都造成了影响,针对大容量存储中NAND Flash存在坏块对其造成的影响,我们主要研究了NAND Flash中坏块出现的原因,对坏块进行的分类,并提出了相应的管理方案。实践证明,经过对坏块的管理,Flash存储数据的安全性和存储速度都有了很大的提升,提高了系统的整体性能。     

基于FPGA和NAND Flash的嵌入式存储系统设计

为了有效解决恶劣工作环境下对体积有特殊要求的数据存储问题,设计了基于FPGA和NAND Flash的小尺寸嵌入式存储系统。系统选用FPGA为控制核心,以NAND Flash作为存储介质,采用LVDS接口存储和回放数据,通过以千兆网与计算机通信,以文件方式管理数据,并采用坏块管理和ECC技术保证数据完整性。实测表明,该系统具有高带宽、体积小等特点,同时具有实时存储、回放、加载、卸载和管理功能,并可在恶劣环境下稳定工作。     

一种使用Flash阵列存储数据的方法研究

在航空航天领域,随着飞行器性能的提升,研制过程中试验所需的数据存储量和数据存储速度也在不断提高。该文基于高速大容量数据存储的目的,利用FPGA的强大数据处理能力,进行Flash存储阵列及流水线管理的设计,并针对Flash阵列坏块检测和突发坏块提出了对应处理方法。通过对不同组合方式的存储阵列速度及存储容量进行研究对比,得到了一种使用Flash阵列进行高速数据存储的设计方法。相较单片存储,设计的存储阵列数据存储容量和速度成倍增加,且存储阵列的有效块利用率在99%以上。     

一种多通道NAND Flash阵列的坏块管理方案

针对多通道NAND Flash阵列对可靠性的要求,提出一种坏块管理方案,优化坏块信息的存储和查询方法,把坏块和替换块地址映射表存储在FRAM中。测试数据证明,方案可以实现多通道NAND Flash阵列的坏块管理,保证了存储的可靠性。优化的坏块表及查询方法缩短了坏块查询时间,FRAM节省了有效块地址映射时间, 同时FRAM的铁电效应,进一步提高了数据存储的可靠性。     

一种NAND Flash动态坏块管理算法的设计与实现

文章针对NAND Flash在大容量数据存储时对可靠性的要求,提出一种基于逻辑一物理块地址映射表的大容量NAND Flash动态坏块管理算法。该方法可彻底屏蔽对坏块的操作,实现对NAND Flash的有效存储,具有较高的实际应用价值。     

基于NAND Flash的海量存储器的设计

针对存储系统中对存储容量和存储带宽的要求不断提高,设计了一款高性能的超大容量数据存储器。该存储器采用NAND Flash作为存储介质,单板载有144片芯片,分为3组,每组48片,降低了单片的存储速度,实现了576 Gbyte的海量存储。设计采用FPGA进行多片NAND Flash芯片并行读写来提高读写带宽,使得大容量高带宽的存储器得以实现。针对NAND Flash存在坏块的缺点,提出了相应的管理方法,保证了数据的可靠性。     

基于闪存的高速大容量存储系统设计

介绍一种基于Flash和FPGA的高速大容量数据存储系统的组成机制和实现方法,并且给出了系统的硬件结构及软件设计流程.在分析了Flash结构和特点的基础上引用并行总线和多级流水技术实现了高速存储,采用ECC数据校验和自动屏蔽闪存坏块的方法提高了数据存储及回放的可靠性.实验结果表明,该存储系统工作稳定,存储速度高、容量大、可靠性好.     

高速数据同步存储系统设计

介绍了一种高数同步存储系统的设计方案。系统使用NAND Flash构建片内存储阵列、同步管理技术和流水线的设计方案提高其存储速度。在Flash的同步模式下的读、写技术基础上,引入了片内Flash阵列管理方法,使整个Flash的存储速度有了大幅度的提高。同时针对Flash的坏块检测问题,引入了片外存储坏块地址的方法,提高了系统的坏快检测效率,保证系统的稳定性的同时,最大程度上提升了系统的性能。测试结果表明,该系统存储速度快、存储容量大、可靠性高。     

基于单片机的Flash存储器坏块自动检测

在深入了解Flash存储器的基础上,采用单片机自动检测存储器无效块。主要通过读取每一块的第l、第2页内容,判断该块的好坏,并给出具体的实现过程,以及部分关键的电路原理图和C语言程序代码。该设计最终实现单片机自动检测Flash坏块的功能,并通过读取ID号检测Flash的性能,同时该设计能够存储和读取lGB数据。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.