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  • pci e PCB设计规范

    This document provides practical, common guidelines for incorporating PCI Express interconnect layouts onto Printed Circuit Boards (PCB) ranging from 4-layer desktop baseboard designs to 10- layer or more server baseboard designs. Guidelines and constraints in this document are intended for use on both baseboard and add-in card PCB designs. This includes interconnects between PCI Express devices located on the same baseboard (chip-to-chip routing) and interconnects between a PCI Express device located “down” on the baseboard and a device located “up” on an add-in card attached through a connector. This document is intended to cover all major components of the physical interconnect including design guidelines for the PCB traces, vias and AC coupling capacitors, as well as add-in card edge-finger and connector considerations. The intent of the guidelines and examples is to help ensure that good high-speed signal design practices are used and that the timing/jitter and loss/attenuation budgets can also be met from end-to-end across the PCI Express interconnect. However, while general physical guidelines and suggestions are given, they may not necessarily guarantee adequate performance of the interconnect for all layouts and implementations. Therefore, designers should consider modeling and simulation of the interconnect in order to ensure compliance to all applicable specifications. The document is composed of two main sections. The first section provides an overview of general topology and interconnect guidelines. The second section concentrates on physical layout constraints where bulleted items at the beginning of a topic highlight important constraints, while the narrative that follows offers additional insight.  

    标签: pci PCB 设计规范

    上传时间: 2014-01-24

    上传用户:s363994250

  • Protel使用中的一些问题和解答

    Q01、如何使一条走线至两个不同位置零件的距离相同?  您可先在Design/Rule/High Speed/Matched Net Lengths的规则中来新增规则设定,最 后再用Tools/EqualizeNet Lengths 来等长化即可。   Q02、在SCHLIB中造一零件其PIN的属性,如何决定是Passive, Input, I/O, Hi- Z,Power,…..?在HELP中能找到说明吗?市面有关 SIM?PLD?的书吗?或贵公司有讲义?  你可在零件库自制零件时点选零件Pin脚,并在Electrical Type里,可以自行设定PIN的 属性,您可参考台科大的Protel sch 99se 里 面有介绍关于SIM的内容。   Q03、请问各位业界前辈,如何能顺利读取pcad8.6版的线路图,烦请告知  Protel 99SE只能读取P-CAD 2000的ASCII档案格式,所以你必须先将P-CAD8.6版的格式 转为P-CAD 2000的档案格式,才能让Protel读取。

    标签: Protel

    上传时间: 2013-11-07

    上传用户:tangsiyun

  • multisim10.0仿真软件破解版下载

    multisim10.0仿真软件破解版下载:【软件介绍】 Multisim本是加拿大图像交互技术公司(Interactive Image Technoligics简称IIT公司)推出的以Windows为基础的仿真工具,被美国NI公司收购后,更名为NI Multisim ,而V10.0是其(即NI,National Instruments)最新推出的Multisim最新版本。 目前美国NI公司的EWB的包含有电路仿真设计的模块Multisim、PCB设计软件Ultiboard、布线引擎Ultiroute及通信电路分析与设计模块Commsim 4个部分,能完成从电路的仿真设计到电路版图生成的全过程。Multisim、Ultiboard、Ultiroute及Commsim 4个部分相互独立,可以分别使用。Multisim、Ultiboard、Ultiroute及Commsim 4个部分有增强专业版(Power Professional)、专业版(Professional)、个人版(Personal)、教育版(Education)、学生版(Student)和演示版(Demo)等多个版本,各版本的功能和价格有着明显的差异。 NI Multisim 10用软件的方法虚拟电子与电工元器件,虚拟电子与电工仪器和仪表,实现了“软件即元器件”、“软件即仪器”。NI Multisim 10是一个原理电路设计、电路功能测试的虚拟仿真软件。 NI Multisim 10的元器件库提供数千种电路元器件供实验选用,同时也可以新建或扩充已有的元器件库,而且建库所需的元器件参数可以从生产厂商的产品使用手册中查到,因此也很方便的在工程设计中使用。 NI Multisim 10的虚拟测试仪器仪表种类齐全,有一般实验用的通用仪器,如万用表、函数信号发生器、双踪示波器、直流电源;而且还有一般实验室少有或没有的仪器,如波特图仪、字信号发生器、逻辑分析仪、逻辑转换器、失真仪、频谱分析仪和网络分析仪等。 NI Multisim 10具有较为详细的电路分析功能,可以完成电路的瞬态分析和稳态分析、 时域和频域分析、器件的线性和非线性分析、电路的噪声分析和失真分析、离散傅里叶分析、电路零极点分析、交直流灵敏度分析等电路分析方法,以帮助设计人员分析电路的性能。 NI Multisim 10可以设计、测试和演示各种电子电路,包括电工学、模拟电路、数字电路、射频电路及微控制器和接口电路等。可以对被仿真的电路中的元器件设置各种故障,如开路、短路和不同程度的漏电等,从而观察不同故障情况下的电路工作状况。在进行仿真的同时,软件还可以存储测试点的所有数据,列出被仿真电路的所有元器件清单,以及存储测试仪器的工作状态、显示波形和具体数据等。 NI Multisim 10有丰富的Help功能,其Help系统不仅包括软件本身的操作指南,更要的是包含有元器件的功能解说,Help中这种元器件功能解说有利于使用EWB进行CAI教学。另外,NI Multisim10还提供了与国内外流行的印刷电路板设计自动化软件Protel及电路仿真软件PSpice之间的文件接口,也能通过Windows的剪贴板把电路图送往文字处理系统中进行编辑排版。支持VHDL和Verilog HDL语言的电路仿真与设计。 利用NI Multisim 10可以实现计算机仿真设计与虚拟实验,与传统的电子电路设计与实验方法相比,具有如下特点:设计与实验可以同步进行,可以边设计边实验,修改调试方便;设计和实验用的元器件及测试仪器仪表齐全,可以完成各种类型的电路设计与实验;可方便地对电路参数进行测试和分析;可直接打印输出实验数据、测试参数、曲线和电路原理图;实验中不消耗实际的元器件,实验所需元器件的种类和数量不受限制,实验成本低,实验速度快,效率高;设计和实验成功的电路可以直接在产品中使用。 NI Multisim 10易学易用,便于电子信息、通信工程、自动化、电气控制类专业学生自学、便于开展综合性的设计和实验,有利于培养综合分析能力、开发和创新的能力。 multisim10.0激活码及破解序列号

    标签: multisim 10.0 仿真软件

    上传时间: 2015-01-03

    上传用户:daoyue

  • ADO.NET in a Nutshell is the most complete and concise source of ADO.NET information available. Besi

    ADO.NET in a Nutshell is the most complete and concise source of ADO.NET information available. Besides being a valuable reference, this book covers a variety of issues that programmers face when developing web applications or web services that rely on database access. Most examples use Microsoft s C# language. The book s CD includes an add-in to integrate the reference with Visual Studio .NET help files.

    标签: information ADO NET available

    上传时间: 2015-01-11

    上传用户:nanfeicui

  • MemCheck Driver Memory Tool The MemCheck code is designed to provide Windows NT/2K/XP driver develop

    MemCheck Driver Memory Tool The MemCheck code is designed to provide Windows NT/2K/XP driver developers with a tool to help in the detection of the following memory handling issues: Buffer overrun Buffer corruption Buffer use after buffer release Double buffer releases

    标签: MemCheck designed Windows develop

    上传时间: 2014-12-05

    上传用户:weiwolkt

  • Demo程序经Keil701编译后

    Demo程序经Keil701编译后,代码量为7-8K,可直接在KeilC51上仿真运行。 使用方法:解压后双击yy项目,点调试即可在串口仿真看到结果。 Demo程序创建了3个任务A、B、C优先级分别为2、3、4,A每秒显示一次,B每3秒显示一次,C每6秒显示一次。从显示结果看,显示3个A后显示1个B,显示6个A和2个B后显示1个C,结果显然正确。用户可以仿照范例运用更多系统API函数写出自己的程序。只要程序中有显示语句就可以用软件仿真器看结果。注意:系统提供的显示函数是并发的,他不是直接显示到串口,而是先输出到显存,用户不必担心IO慢速操作影响程序运行。串口输入也采用了同样的技术,他使得用户在CPU忙于处理其他任务时照样可以盲打输入命令。 将EXL2-shell目录下的文件覆盖yy目录下的同名文件,将word.c、yyshell.c、yyshellsub.c、mystring.c加入项目,删除yy1.c,编译后调试即可。输入help可得到在线帮助,具体命令用法见文章说明。 yangye网友推荐http://www.sics.se/~adam/lwip/网站学习TCPIP,该网站开放源代码的lwip是专为8bit和16bitMCU设计的TCPIP协议栈,已在多种CPU上移植成功,推荐大家下载。

    标签: Demo Keil 701 程序

    上传时间: 2014-11-01

    上传用户:hopy

  • A simple utility to split a concatenated vCard format file into separate files (IETF RFC 2426 - vCar

    A simple utility to split a concatenated vCard format file into separate files (IETF RFC 2426 - vCard MIME Directory Profile). It splits on the BEGIN:VCARD and END:VCARD tags. It was created to help import a Lotus Organizer export file into Palm Desktop

    标签: concatenated separate utility simple

    上传时间: 2013-12-20

    上传用户:gxf2016

  • ATmega8 taillight circuitA more complex C program that implements different flashing patterns under

    ATmega8 taillight circuitA more complex C program that implements different flashing patterns under the control of both the push buttons and potentiometer. Use your imagination to come up with some novel ideas here. Remember however that more marks are to be awarded for the quality of the code than for the novelness of the patterns.

    标签: implements taillight different circuitA

    上传时间: 2013-11-27

    上传用户:zhuimenghuadie

  • Overview In this chapter I introduce Borland C++Builder (BCB) and explain what it is about. I also d

    Overview In this chapter I introduce Borland C++Builder (BCB) and explain what it is about. I also devote considerable time to explaining the purpose of this book and the philosophy behind my approach to technical writing. Technical subjects covered in this chapter include Creating a simple Multimedia RAD program that plays movies, WAV files, and MIDI files. Shutting down the BCB RAD programming tools and writing raw Windows API code instead. Creating components dynamically on the heap at runtime. Setting up event handlers (closures) dynamically at runtime. A brief introduction to using exceptions. This topic is covered in more depth in Chapter 5, "Exceptions." A brief introduction to ANSI strings. This subject is covered in more depth in Chapter 3, "C++Builder and the VCL." Using the online help. Greping through the include and source files that come with the product and with this book.

    标签: introduce Overview Borland Builder

    上传时间: 2014-01-04

    上传用户:小鹏

  • 微型操作系统

    微型操作系统,想知道操作系统秘密的初学者可以在这起步。 文件列表: 1 micro-os.img 已编好的软盘映象。 2 micro-os_kernel.bin 命令核心二进制代码 3 micro-os_loader.boot 启动二进制代码 4 micro-os_loader.asm micro-os_kernel.asm 源文件 用法:1 编译源文件 2 将loader.boot 用工具写入软盘0道0头1扇区 kernel.bin写入0.0.2-0.0.n (n<10) 在 0.0.1的最后两个字节写入55h ,aah 3 启动 有几个可用命令 help cls quit exit reboot

    标签: 操作系统

    上传时间: 2013-12-11

    上传用户:zwei41