附件是一款PCB阻抗匹配计算工具,点击CITS25.exe直接打开使用,无需安装。附件还带有PCB连板的一些计算方法,连板的排法和PCB联板的设计验验。 PCB设计的經驗建議: 1.一般連板長寬比率為1:1~2.5:1,同時注意For FuJi Machine:a.最大進板尺寸為:450*350mm, 2.針對有金手指的部分,板邊處需作掏空處理,建議不作為連板的部位. 3.連板方向以同一方向為優先,考量對稱防呆,特殊情況另作處理. 4.連板掏空長度超過板長度的1/2時,需加補強邊. 5.陰陽板的設計需作特殊考量. 6.工藝邊需根據實際需要作設計調整,軌道邊一般不少於6mm,實際中需考量板邊零件的排布,軌道設備正常卡壓距離為不少於3mm,及符合實際要求下的連板經濟性. 7.FIDUCIAL MARK或稱光學定位點,一般設計在對角處,為2個或4個,同時MARK點面需平整,無氧化,脫落現象;定位孔設計在板邊,為對稱設計,一般為4個,直徑為3mm,公差為±0.01inch. 8.V-cut深度需根據連板大小及基板板厚考量,角度建議為不少於45°. 9.連板設計的同時,需基於基板的分板方式考量<人工(治具)還是使用分板設備>. 10.使用針孔(郵票孔)聯接:需請考慮斷裂后的毛刺,及是否影響COB工序的Bonding机上的夾具穩定工作,還應考慮是否有無影響插件過軌道,及是否影響裝配組裝.
上传时间: 2013-10-15
上传用户:3294322651
怎样使用Nios II处理器来构建多处理器系统 Chapter 1. Creating Multiprocessor Nios II Systems Introduction to Nios II Multiprocessor Systems . . . . . . . . . . . . . . 1–1 Benefits of Hierarchical Multiprocessor Systems . . . . . . . . . . . . . . . 1–2 Nios II Multiprocessor Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2 Multiprocessor Tutorial Prerequisites . . . . . . . . . . . . . . . . . . . . . . . 1–3 Hardware Designs for Peripheral Sharing . . . . . . . . . . . .. . . . . . . . 1–3 Autonomous Multiprocessors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3 Multiprocessors that Share Peripherals . . . . . . . . . . . . . . . . . . . . . . 1–4 Sharing Peripherals in a Multiprocessor System . . . . . . . . . . . . . . . . . 1–4 Sharing Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–6 The Hardware Mutex Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–7 Sharing Peripherals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . 1–8 Overlapping Address Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–8 Software Design Considerations for Multiple Processors . . .. . . . . 1–9 Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–9 Boot Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1–13 Debugging Nios II Multiprocessor Designs . . . . . . . . . . . . . . . . 1–15 Design Example: The Dining Philosophers’ Problem . . . . .. . . 1–15 Hardware and Software Requirements . . . . . . . . . . . . . . . .. . . 1–16 Installation Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–17 Creating the Hardware System . . . . . . . . . . . . . . .. . . . . . 1–17 Getting Started with the multiprocessor_tutorial_start Design Example 1–17 Viewing a Philosopher System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–18 Philosopher System Pipeline Bridges . . . . . . . . . . . . . . . . . . . . . 1–19 Adding Philosopher Subsystems . . . . . . . . . . . . . . . . . . . . . . . . . . 1–21 Connecting the Philosopher Subsystems . . . . . . . . . . . . .. . . . . 1–22 Viewing the Complete System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–27 Generating and Compiling the System . . . . . . . . . . . . . . . . . .. 1–28
上传时间: 2013-11-21
上传用户:lo25643
现代的电子设计和芯片制造技术正在飞速发展,电子产品的复杂度、时钟和总线频率等等都呈快速上升趋势,但系统的电压却不断在减小,所有的这一切加上产品投放市场的时间要求给设计师带来了前所未有的巨大压力。要想保证产品的一次性成功就必须能预见设计中可能出现的各种问题,并及时给出合理的解决方案,对于高速的数字电路来说,最令人头大的莫过于如何确保瞬时跳变的数字信号通过较长的一段传输线,还能完整地被接收,并保证良好的电磁兼容性,这就是目前颇受关注的信号完整性(SI)问题。本章就是围绕信号完整性的问题,让大家对高速电路有个基本的认识,并介绍一些相关的基本概念。 第一章 高速数字电路概述.....................................................................................51.1 何为高速电路...............................................................................................51.2 高速带来的问题及设计流程剖析...............................................................61.3 相关的一些基本概念...................................................................................8第二章 传输线理论...............................................................................................122.1 分布式系统和集总电路.............................................................................122.2 传输线的RLCG 模型和电报方程...............................................................132.3 传输线的特征阻抗.....................................................................................142.3.1 特性阻抗的本质.................................................................................142.3.2 特征阻抗相关计算.............................................................................152.3.3 特性阻抗对信号完整性的影响.........................................................172.4 传输线电报方程及推导.............................................................................182.5 趋肤效应和集束效应.................................................................................232.6 信号的反射.................................................................................................252.6.1 反射机理和电报方程.........................................................................252.6.2 反射导致信号的失真问题.................................................................302.6.2.1 过冲和下冲.....................................................................................302.6.2.2 振荡:.............................................................................................312.6.3 反射的抑制和匹配.............................................................................342.6.3.1 串行匹配.........................................................................................352.6.3.1 并行匹配.........................................................................................362.6.3.3 差分线的匹配.................................................................................392.6.3.4 多负载的匹配.................................................................................41第三章 串扰的分析...............................................................................................423.1 串扰的基本概念.........................................................................................423.2 前向串扰和后向串扰.................................................................................433.3 后向串扰的反射.........................................................................................463.4 后向串扰的饱和.........................................................................................463.5 共模和差模电流对串扰的影响.................................................................483.6 连接器的串扰问题.....................................................................................513.7 串扰的具体计算.........................................................................................543.8 避免串扰的措施.........................................................................................57第四章 EMI 抑制....................................................................................................604.1 EMI/EMC 的基本概念..................................................................................604.2 EMI 的产生..................................................................................................614.2.1 电压瞬变.............................................................................................614.2.2 信号的回流.........................................................................................624.2.3 共模和差摸EMI ..................................................................................634.3 EMI 的控制..................................................................................................654.3.1 屏蔽.....................................................................................................654.3.1.1 电场屏蔽.........................................................................................654.3.1.2 磁场屏蔽.........................................................................................674.3.1.3 电磁场屏蔽.....................................................................................674.3.1.4 电磁屏蔽体和屏蔽效率.................................................................684.3.2 滤波.....................................................................................................714.3.2.1 去耦电容.........................................................................................714.3.2.3 磁性元件.........................................................................................734.3.3 接地.....................................................................................................744.4 PCB 设计中的EMI.......................................................................................754.4.1 传输线RLC 参数和EMI ........................................................................764.4.2 叠层设计抑制EMI ..............................................................................774.4.3 电容和接地过孔对回流的作用.........................................................784.4.4 布局和走线规则.................................................................................79第五章 电源完整性理论基础...............................................................................825.1 电源噪声的起因及危害.............................................................................825.2 电源阻抗设计.............................................................................................855.3 同步开关噪声分析.....................................................................................875.3.1 芯片内部开关噪声.............................................................................885.3.2 芯片外部开关噪声.............................................................................895.3.3 等效电感衡量SSN ..............................................................................905.4 旁路电容的特性和应用.............................................................................925.4.1 电容的频率特性.................................................................................935.4.3 电容的介质和封装影响.....................................................................955.4.3 电容并联特性及反谐振.....................................................................955.4.4 如何选择电容.....................................................................................975.4.5 电容的摆放及Layout ........................................................................99第六章 系统时序.................................................................................................1006.1 普通时序系统...........................................................................................1006.1.1 时序参数的确定...............................................................................1016.1.2 时序约束条件...................................................................................1066.2 源同步时序系统.......................................................................................1086.2.1 源同步系统的基本结构...................................................................1096.2.2 源同步时序要求...............................................................................110第七章 IBIS 模型................................................................................................1137.1 IBIS 模型的由来...................................................................................... 1137.2 IBIS 与SPICE 的比较.............................................................................. 1137.3 IBIS 模型的构成...................................................................................... 1157.4 建立IBIS 模型......................................................................................... 1187.4 使用IBIS 模型......................................................................................... 1197.5 IBIS 相关工具及链接..............................................................................120第八章 高速设计理论在实际中的运用.............................................................1228.1 叠层设计方案...........................................................................................1228.2 过孔对信号传输的影响...........................................................................1278.3 一般布局规则...........................................................................................1298.4 接地技术...................................................................................................1308.5 PCB 走线策略............................................................................................134
标签: 信号完整性
上传时间: 2013-11-01
上传用户:xitai
第一部分 信号完整性知识基础.................................................................................5第一章 高速数字电路概述.....................................................................................51.1 何为高速电路...............................................................................................51.2 高速带来的问题及设计流程剖析...............................................................61.3 相关的一些基本概念...................................................................................8第二章 传输线理论...............................................................................................122.1 分布式系统和集总电路.............................................................................122.2 传输线的RLCG 模型和电报方程...............................................................132.3 传输线的特征阻抗.....................................................................................142.3.1 特性阻抗的本质.................................................................................142.3.2 特征阻抗相关计算.............................................................................152.3.3 特性阻抗对信号完整性的影响.........................................................172.4 传输线电报方程及推导.............................................................................182.5 趋肤效应和集束效应.................................................................................232.6 信号的反射.................................................................................................252.6.1 反射机理和电报方程.........................................................................252.6.2 反射导致信号的失真问题.................................................................302.6.2.1 过冲和下冲.....................................................................................302.6.2.2 振荡:.............................................................................................312.6.3 反射的抑制和匹配.............................................................................342.6.3.1 串行匹配.........................................................................................352.6.3.1 并行匹配.........................................................................................362.6.3.3 差分线的匹配.................................................................................392.6.3.4 多负载的匹配.................................................................................41第三章 串扰的分析...............................................................................................423.1 串扰的基本概念.........................................................................................423.2 前向串扰和后向串扰.................................................................................433.3 后向串扰的反射.........................................................................................463.4 后向串扰的饱和.........................................................................................463.5 共模和差模电流对串扰的影响.................................................................483.6 连接器的串扰问题.....................................................................................513.7 串扰的具体计算.........................................................................................543.8 避免串扰的措施.........................................................................................57第四章 EMI 抑制....................................................................................................604.1 EMI/EMC 的基本概念..................................................................................604.2 EMI 的产生..................................................................................................614.2.1 电压瞬变.............................................................................................614.2.2 信号的回流.........................................................................................624.2.3 共模和差摸EMI ..................................................................................634.3 EMI 的控制..................................................................................................654.3.1 屏蔽.....................................................................................................654.3.1.1 电场屏蔽.........................................................................................654.3.1.2 磁场屏蔽.........................................................................................674.3.1.3 电磁场屏蔽.....................................................................................674.3.1.4 电磁屏蔽体和屏蔽效率.................................................................684.3.2 滤波.....................................................................................................714.3.2.1 去耦电容.........................................................................................714.3.2.3 磁性元件.........................................................................................734.3.3 接地.....................................................................................................744.4 PCB 设计中的EMI.......................................................................................754.4.1 传输线RLC 参数和EMI ........................................................................764.4.2 叠层设计抑制EMI ..............................................................................774.4.3 电容和接地过孔对回流的作用.........................................................784.4.4 布局和走线规则.................................................................................79第五章 电源完整性理论基础...............................................................................825.1 电源噪声的起因及危害.............................................................................825.2 电源阻抗设计.............................................................................................855.3 同步开关噪声分析.....................................................................................875.3.1 芯片内部开关噪声.............................................................................885.3.2 芯片外部开关噪声.............................................................................895.3.3 等效电感衡量SSN ..............................................................................905.4 旁路电容的特性和应用.............................................................................925.4.1 电容的频率特性.................................................................................935.4.3 电容的介质和封装影响.....................................................................955.4.3 电容并联特性及反谐振.....................................................................955.4.4 如何选择电容.....................................................................................975.4.5 电容的摆放及Layout ........................................................................99第六章 系统时序.................................................................................................1006.1 普通时序系统...........................................................................................1006.1.1 时序参数的确定...............................................................................1016.1.2 时序约束条件...................................................................................1063.2 高速设计的问题.......................................................................................2093.3 SPECCTRAQuest SI Expert 的组件.......................................................2103.3.1 SPECCTRAQuest Model Integrity .................................................2103.3.2 SPECCTRAQuest Floorplanner/Editor .........................................2153.3.3 Constraint Manager .......................................................................2163.3.4 SigXplorer Expert Topology Development Environment .......2233.3.5 SigNoise 仿真子系统......................................................................2253.3.6 EMControl .........................................................................................2303.3.7 SPECCTRA Expert 自动布线器.......................................................2303.4 高速设计的大致流程...............................................................................2303.4.1 拓扑结构的探索...............................................................................2313.4.2 空间解决方案的探索.......................................................................2313.4.3 使用拓扑模板驱动设计...................................................................2313.4.4 时序驱动布局...................................................................................2323.4.5 以约束条件驱动设计.......................................................................2323.4.6 设计后分析.......................................................................................233第四章 SPECCTRAQUEST SIGNAL EXPLORER 的进阶运用..........................................2344.1 SPECCTRAQuest Signal Explorer 的功能包括:................................2344.2 图形化的拓扑结构探索...........................................................................2344.3 全面的信号完整性(Signal Integrity)分析.......................................2344.4 完全兼容 IBIS 模型...............................................................................2344.5 PCB 设计前和设计的拓扑结构提取.......................................................2354.6 仿真设置顾问...........................................................................................2354.7 改变设计的管理.......................................................................................2354.8 关键技术特点...........................................................................................2364.8.1 拓扑结构探索...................................................................................2364.8.2 SigWave 波形显示器........................................................................2364.8.3 集成化的在线分析(Integration and In-process Analysis) .236第五章 部分特殊的运用...............................................................................2375.1 Script 指令的使用..................................................................................2375.2 差分信号的仿真.......................................................................................2435.3 眼图模式的使用.......................................................................................249第四部分:HYPERLYNX 仿真工具使用指南............................................................251第一章 使用LINESIM 进行前仿真.......................................................................2511.1 用LineSim 进行仿真工作的基本方法...................................................2511.2 处理信号完整性原理图的具体问题.......................................................2591.3 在LineSim 中如何对传输线进行设置...................................................2601.4 在LineSim 中模拟IC 元件.....................................................................2631.5 在LineSim 中进行串扰仿真...................................................................268第二章 使用BOARDSIM 进行后仿真......................................................................2732.1 用BOARDSIM 进行后仿真工作的基本方法...................................................2732.2 BoardSim 的进一步介绍..........................................................................2922.3 BoardSim 中的串扰仿真..........................................................................309
上传时间: 2013-11-07
上传用户:aa7821634
0RCAD全能混合电路仿真:第一部分 0rCAD环境与Capture第l章 OrCAD PSpice简介1—1 SPICE的起源1—2 OrCAD PSpice的特点1—3 评估版光盘的安装1—4 评估版的限制1—4—1 Capture CIS 9.0评估版的限制1—4—2 PSpiceA/D9.0评估版限制1—5 系统需求1—6 PSpice可执行的仿真分析1—6—1 基本分析1—6—2 高级分析1—7 Capture与PSpice名词解释1—7—1 文件与文件编辑程序1—7—2 对象、电气对象与属性1—7—3 元件、元件库与模型1—7—4 绘图页、标题区与边框1—7—5 绘图页文件夹、设计、设计快取内存1—7—6 项目与项目管理程序
上传时间: 2013-10-23
上传用户:wincoder
减小电磁干扰的印刷电路板设计原则 内 容 摘要……1 1 背景…1 1.1 射频源.1 1.2 表面贴装芯片和通孔元器件.1 1.3 静态引脚活动引脚和输入.1 1.4 基本回路……..2 1.4.1 回路和偶极子的对称性3 1.5 差模和共模…..3 2 电路板布局…4 2.1 电源和地…….4 2.1.1 感抗……4 2.1.2 两层板和四层板4 2.1.3 单层板和二层板设计中的微处理器地.4 2.1.4 信号返回地……5 2.1.5 模拟数字和高压…….5 2.1.6 模拟电源引脚和模拟参考电压.5 2.1.7 四层板中电源平面因该怎么做和不应该怎么做…….5 2.2 两层板中的电源分配.6 2.2.1 单点和多点分配.6 2.2.2 星型分配6 2.2.3 格栅化地.7 2.2.4 旁路和铁氧体磁珠……9 2.2.5 使噪声靠近磁珠……..10 2.3 电路板分区…11 2.4 信号线……...12 2.4.1 容性和感性串扰……...12 2.4.2 天线因素和长度规则...12 2.4.3 串联终端传输线…..13 2.4.4 输入阻抗匹配...13 2.5 电缆和接插件……...13 2.5.1 差模和共模噪声……...14 2.5.2 串扰模型……..14 2.5.3 返回线路数目..14 2.5.4 对板外信号I/O的建议14 2.5.5 隔离噪声和静电放电ESD .14 2.6 其他布局问题……...14 2.6.1 汽车和用户应用带键盘和显示器的前端面板印刷电路板...15 2.6.2 易感性布局…...15 3 屏蔽..16 3.1 工作原理…...16 3.2 屏蔽接地…...16 3.3 电缆和屏蔽旁路………………..16 4 总结…………………………………………17 5 参考文献………………………17
上传时间: 2013-10-22
上传用户:a6697238
ARM通讯 H-JTAG 是一款简单易用的的调试代理软件,功能和流行的MULTI-ICE 类似。H-JTAG 包括两个工具软件:H-JTAG SERVER 和H-FLASHER。其中,H-JTAG SERVER 实现调试代理的功能,而H-FLASHER则实现了FLASH 烧写的功能。H-JTAG 的基本结构如下图1-1所示。 H-JTAG支持所有基于ARM7 和ARM9的芯片的调试,并且支持大多数主流的ARM调试软件,如ADS、RVDS、IAR 和KEIL。通过灵活的接口配置,H-JTAG 可以支持WIGGLER,SDT-JTAG 和用户自定义的各种JTAG 调试小板。同时,附带的H-FLASHER 烧写软件还支持常用片内片外FLASH 的烧写。使用H-JTAG,用户能够方便的搭建一个简单易用的ARM 调试开发平台。H-JTAG 的功能和特定总结如下: 1. 支持 RDI 1.5.0 以及 1.5.1; 2. 支持所有ARM7 以及 ARM9 芯片; 3. 支持 THUMB 以及ARM 指令; 4. 支持 LITTLE-ENDIAN 以及 BIG-ENDIAN; 5. 支持 SEMIHOSTING; 6. 支持 WIGGLER, SDT-JTAG和用户自定义JTAG调试板; 7. 支持 WINDOWS 9.X/NT/2000/XP; 8.支持常用FLASH 芯片的编程烧写; 9. 支持LPC2000 和AT91SAM 片内FLASH 的自动下载;
上传时间: 2013-11-19
上传用户:水中浮云
打印“魔方阵”。所谓“魔方阵”是指这样的方阵,它的每一行、每一列和对角线之和均相等。例如,三阶魔方阵为: 8 1 6 3 5 7 4 9 2 要求打印出由1到n*n的自然数构成的魔方阵。
上传时间: 2013-12-17
上传用户:hustfanenze
暂时只支持jpeg2000支持的 cdf97 和spline53 可以这样来测试: x=imread( E:\study\jpeg2000\images\lena.tif ) % see the decomposition coefficients y=wavelift(x, 1, spl53 ) using spline 5/3 wavelet figure subplot(1,2,1) imshow(x) subplot(1,2,2) imshow(mat2gray(y)) % see the reconstruction precision yy=wavelift(x, 5) using cdf 9/7 wavelet ix=wavelift(yy,-5) inverse sum(sum((double(x)-ix).^2))
标签: 2000 imageslena studyjpeg imread
上传时间: 2014-01-14
上传用户:懒龙1988
zemax源码: This DLL models an anamorphic aspheric surface. This surface is essentially an even aspheric surface with different terms for the x and y directions. The sag is given by: Z = ((CX*x*x)+(CY*y*y)) / (1 + sqrt(1-((1+KX)*CX*CX*x*x)-((1+KY)*CY*CY*y*y))) + AR*( (1 - AP)*x*x + (1 + AP)*y*y )^2 + BR*( (1 - BP)*x*x + (1 + BP)*y*y )^3 + CR*( (1 - CP)*x*x + (1 + CP)*y*y )^4 + DR*( (1 - DP)*x*x + (1 + DP)*y*y )^5 Note the terms AR, BR, CR, and DR ... have units of length to the -3, -5, -7, and -9 power. The terms AP, BP, CP, and DP are dimensionless. The surface is rotationally symmetric only if AP = BP = CP = DP == 0 and CX = CY and KX = KY.
标签: surface This essentially anamorphic
上传时间: 2015-07-25
上传用户:lht618