半導體的產品很多,應用的場合非常廣泛,圖一是常見的幾種半導體元件外型。半導體元件一般是以接腳形式或外型來劃分類別,圖一中不同類別的英文縮寫名稱原文為 PDID:Plastic Dual Inline Package SOP:Small Outline Package SOJ:Small Outline J-Lead Package PLCC:Plastic Leaded Chip Carrier QFP:Quad Flat Package PGA:Pin Grid Array BGA:Ball Grid Array 雖然半導體元件的外型種類很多,在電路板上常用的組裝方式有二種,一種是插入電路板的銲孔或腳座,如PDIP、PGA,另一種是貼附在電路板表面的銲墊上,如SOP、SOJ、PLCC、QFP、BGA。 從半導體元件的外觀,只看到從包覆的膠體或陶瓷中伸出的接腳,而半導體元件真正的的核心,是包覆在膠體或陶瓷內一片非常小的晶片,透過伸出的接腳與外部做資訊傳輸。圖二是一片EPROM元件,從上方的玻璃窗可看到內部的晶片,圖三是以顯微鏡將內部的晶片放大,可以看到晶片以多條銲線連接四周的接腳,這些接腳向外延伸並穿出膠體,成為晶片與外界通訊的道路。請注意圖三中有一條銲線從中斷裂,那是使用不當引發過電流而燒毀,致使晶片失去功能,這也是一般晶片遭到損毀而失效的原因之一。 圖四是常見的LED,也就是發光二極體,其內部也是一顆晶片,圖五是以顯微鏡正視LED的頂端,可從透明的膠體中隱約的看到一片方型的晶片及一條金色的銲線,若以LED二支接腳的極性來做分別,晶片是貼附在負極的腳上,經由銲線連接正極的腳。當LED通過正向電流時,晶片會發光而使LED發亮,如圖六所示。 半導體元件的製作分成兩段的製造程序,前一段是先製造元件的核心─晶片,稱為晶圓製造;後一段是將晶中片加以封裝成最後產品,稱為IC封裝製程,又可細分成晶圓切割、黏晶、銲線、封膠、印字、剪切成型等加工步驟,在本章節中將簡介這兩段的製造程序。
上传时间: 2013-11-04
上传用户:372825274
工程技术上所谓的制冷,就是使某一系统(即空间或物体)的温度低于周围环境介质的温度,并维持这个低温的过程,这里所说的环境介质是指自然界的空气和水。制冷与空调设备以流体(气体与液体的总称)作为载能物质,实现热能与其它形式能量(主要为机械能)之间的转换或热能的转移。本章介绍流体的性质、热能与机械能之间的转换规律和热量的传递规律,这些知识是空调技术必不可少的理论基础。
标签: 制冷技术
上传时间: 2013-11-08
上传用户:huyiming139
可编程控制器(PLC)是在传统的继电器基础上结合计算机技术的一种数字运算操作的控制装置,应用非常广泛。 本书是为初学继电器顺序控制、可编程控制器以及传感器使用方法的读者而编写的实用入门书。本书基本按照“问题一电路设计一接线一实施”步骤,利用丰富实例、通俗易懂地讲解相关内容,内容涉及顺序控制的基本知识、继电器顺序控制的基础与应用、可编程控制器的基础知识、可编程控制器的指令与基本电路及可编程控制器的应用电路等,并且每章后均给出实践题,在最后给出相应的答案。 本书适合作为刚刚参加工作的技术人员的入门书,以及工科学生的实践用书。
上传时间: 2015-01-02
上传用户:mh_zhaohy
本书系统地介绍了机器人技术相关的基本知识,主要包括:绪论;机器人结构设计基础;机器人操作手运动学;机器人操作手动力学;操作机器人关节伺服驱动技术;机器人控制;机器人传感器。本书注重将机器人基础理论与应用技术相结合,力求反映国内外机器人研究领域的新进展。
上传时间: 2013-10-28
上传用户:JasonC
Abstract: How can an interface change a happy face to a sad face? Engineers have happy faces when an interface works properly.Sad faces indicate failure somewhere. Because interfaces between microprocessors and ICs are simple—even easy—they are oftenignored until interface failure causes sad faces all around. In this article, we discuss a common SPI error that can be almostimpossible to find in a large system. Links to interface tutorial information are provided for complete information. Noise as a systemissue and ICs to minimize its effects are also described.
上传时间: 2013-11-18
上传用户:zgz317
SnackAmp is a powerful multi-platform audio music (mp3, ogg ,wav, streams ...) player and organizer for large music collections. Manage your entire collection, including ID3 tagging and auto-playlisting. Integrated web server for remote control/streaming
标签: multi-platform organizer SnackAmp powerful
上传时间: 2013-12-22
上传用户:3到15
本程序是用c++实现的多功能文本编辑器,它除了可以实现一般文本的编辑功能,还增加了保存文档a(save), 转为大写m(large),改为小写k(small),复制段j(copy),中英文转换t(language)等功能
上传时间: 2013-12-23
上传用户:wuyuying
The Art of Assembly Language Amazing! You’re actually reading this. That puts you into one of three categories: a student who is being forced to read this stuff for a class, someone who picked up this book by accident (probably because you have yet to be indoctrinated by the world at large), or one of the few who actually have an interest in learning assembly language.
标签: Assembly Language actually Amazing
上传时间: 2015-04-30
上传用户:asddsd
In most software-development organizations, the testing program functions as the final "quality gate" for an application, allowing or preventing the move from the comfort of the software-engineering environment into the real world. With this role comes a large responsibility: The success of an application, and possibly of theorganization, can rest on the quality of the software product.
标签: software-development organizations functions the
上传时间: 2015-05-03
上传用户:s363994250
In this book, we aim to give you an introduction to a wide variety of topics important to you as a developer using UNIX. The word Beginning in the title refers more to the content than to your skill level. We ve structured the book to help you learn more about what UNIX has to offer, however much experience you have already. UNIX programming is a large field and we aim to cover enough about a wide range of topics to give you a good beginning in each subject.
标签: introduction important you to
上传时间: 2013-12-22
上传用户:youmo81