毕业设计英文翻译资料

毕业设计英文翻译资料
题目：超声波测距仪的设计与制作
院（系）：
专业：计算机通信工程
学生姓名：张社强
班级：
学号：
指导教师：刘争红
年月日
Integrated circuit
In electronics, an integrated circuit (also known as IC, microcircuit, microchip, silicon chip, or chip) is a miniaturized electronic circuit (consisting mainly of semiconductor devices, as well as passive components) that has been manufactured in the surface of a thin substrate of semiconductor material. Integrated circuits are used in almost all electronic equipment in use today and have revolutionized the world of electronics.
Integrated circuits were made possible by experimental discoveries which showed that semiconductor devices could perform the functions of vacuum tubes, and by mid-20th-century technology advancements in semiconductor device fabrication. The integration of large numbers of tiny transistors into a small chip was an enormous improvement over the manual assembly of circuits using electronic components. The integrated circuit's mass production capability, reliability, and building-block approach to circuit design ensured the rapid adoption of standardized ICs in place of designs using discrete transistors.
There are two main advantages of ICs over discrete circuits: cost and performance. Cost is low because the chips, with all their components, are printed as a unit by photolithography and not constructed one transistor at a time. Furthermore, much less material is used to construct a circuit as a packaged IC die than as a discrete circuit. Performance is high since the components switch quickly and consume little power (compared to their discrete counterparts) because the components are small and close together. As of 2006, chip areas range from a few square millimeters to around 350 mm2, with up to 1 million transistors per mm2.
Among the most advanced integrated circuits are the microprocessors or "cores", which control everything from computers to cellular phones to digital microwave ovens. Digital memory chips and ASICs are examples of other families of integrated circuits that are important to the modern information society. While the cost of designing and developing a complex integrated circuit is quite high, when spread across typically millions of production units the individual IC cost is minimized. The performance of ICs is high because the small size allows short traces which in turn allows low power logic (such as CMOS) to be used at fast switching speeds.
ICs have consistently migrated to smaller feature sizes over the years, allowing more circuitry to be packed on each chip. This increased capacity per unit area can be used to decrease cost and/or increase functionality—see Moore's law which, in its modern interpretation, states that the number of transistors in an integrated circuit doubles every two years. In general, as the
feature size shrinks, almost everything improves—the cost per unit and the switching power consumption go down, and the speed goes up. However, ICs with nanometer-scale devices are not without their problems, principal among which is leakage current (see subthreshold leakage for a discussion of this), although these problems are not insurmountable and will likely be solved or at least ameliorated by the introduction of high-k dielectrics. Since these speed and power consumption gains are apparent to the end user, there is fierce competition among the manufacturers to use finer geometries. This process, and the expected progress over the next few years, is well described by the International Technology Roadmap for Semiconductors (ITRS).
Only a half century after their development was initiated, integrated circuits have become ubiquitous. Computers, cellular phones, and other digital appliances are now inextricable parts of the structure of modern societies. That is, modern computing, communications, manufacturing and transport systems, including the Internet, all depend on the existence of integrated circuits.
Integrated circuits can be classified into analog, digital and mixed signal (both analog and digital on the same chip).
Digital integrated circuits can contain anything from one to millions of logic gates, flip-flops, multiplexers, and other circuits in a few square millimeters. The small size of these circuits allows high speed, low power dissipation,
and reduced manufacturing cost compared with board-level integration. These digital ICs, typically microprocessors, DSPs, and micro controllers work using binary mathematics to process "one" and "zero" signals.
Analog ICs, such as sensors, power management circuits, and operational amplifiers, work by processing continuous signals. They perform functions like amplification, active filtering, demodulation, mixing, etc. ICs can also combine analog and digital circuits on a single chip to create functions such as A/D converters and D/A converters. Such circuits offer smaller size and lower cost, but must carefully account for signal interference.
The semiconductors of the periodic table of the chemical elements were identified as the most likely materials for a solid state vacuum tube by researchers like William Shockley at Bell Laboratories starting in the 1930s. Starting with copper oxide, proceeding to germanium, then silicon, the materials were systematically studied in the 1940s and 1950s. Today, silicon monocrystals are the main substrate used for integrated circuits (ICs) although some III-V compounds of the periodic table such as gallium arsenide are used for specialized applications like LEDs, lasers, solar cells and the highest-speed integrated circuits. It took decades to perfect methods of creating crystals without defects in the crystalline structure of the
semiconducting material.
Semiconductor ICs are fabricated in a layer process which includes these key process steps: Imaging
Deposition
Etching
The main process steps are supplemented by doping and cleaning.
Integrated circuits are composed of many overlapping layers, each defined by photolithography, and normally shown in different colors. Some layers mark where various dopants are diffused into the substrate (called diffusion layers), some define where additional ions are implanted (implant layers), some define the conductors (polysilicon or metal layers), and some define the connections between the conducting layers (via or contact layers). All components are constructed from a specific combination of these layers.
In a self-aligned CMOS process, a transistor is formed wherever the gate layer (polysilicon or metal) crosses a diffusion layer.
Since a CMOS device only draws current on the transition between logic states, CMOS devices consume much less current than bipolar devices.
A random access memory is the most regular type of integrated circuit; the highest density devices are thus memories; but even a microprocessor will have memory on the chip. Although the structures are intricate – with widths which have been shrinking for decades –the layers remain much thinner than the device widths. The layers of material are fabricated much like a photographic process, although light waves in the visible spectrum cannot be used to "expose" a layer of material, as they would be too large for the features. Thus photons of higher frequencies (typically ultraviolet) are used to create the patterns for each layer. Because each feature is so small, electron microscopes are essential tools for a process engineer who might be debugging a fabrication process.
The earliest integrated circuits were packaged in ceramic flat packs, which continued to be used by the military for their reliability and small size for many years. Commercial circuit packaging quickly moved to the dual in-line package (DIP), first in ceramic and later in plastic. In the 1980s pin counts of VLSI circuits exceeded the practical limit for DIP packaging, leading to pin grid array (PGA) and leadless chip carrier (LCC) packages. Surface mount packaging appeared in the early 1980s and became popular in the late 1980s, using finer lead pitch with leads formed as either gull-wing or J-lead, as exemplified by small-outline integrated circuit -- a carrier which occupies an area about 30 – 50% less than an equivalent DIP, with a typical thickness that is 70% less. This package has "gull wing" leads protruding from the two long sides and a lead spacing of 0.050 inches.
In the late 1990s, PQFP and TSOP packages became the most common for high pin count devices, though PGA packages are still often used for high-end microprocessors. Intel and AMD are currently transitioning from PGA packages on high-end microprocessors to land grid array (LGA) packages.
Ball grid array (BGA) packages have existed since the 1970s. Flip-chip Ball Grid Array packages, which allow for much higher pin count than other package types, were developed in the 1990s.
Most integrated circuits large enough to include identifying information include four common sections: the manufacturer's name or logo, the part number, a part production batch number and/or serial number, and a four-digit code that identifies when the chip was manufactured. Extremely small surface mount technology parts often bear only a number used in a manufacturer's lookup table to find the chip characteristics.
The manufacturing date is commonly represented as a two-digit year followed by a two-digit week code, such that a part bearing the code 8341 was manufactured in week 41 of 1983, or approximately in October 1983.
Structure and function of the MCS-51 series
Structure and function of the MCS-51 series one-chip computer is a name of a piece of one-chip computer series which Intel Company produces. This company introduced 8 top-grade one-chip computers of MCS-51 series in 1980 after introducing 8 one-chip computers of MCS-48 series in 1976. It belong to a lot of kinds this line of one-chip computer the chips have,such as 8051, 8031, 8751, 80C51BH, 80C31BH,etc., their basic composition, basic performance and instruction system are all the same. 8051 daily representatives- 51 serial one-chip computers .
An one-chip computer system is made up of several following parts: ( 1) One microprocessor of 8 (CPU). ( 2) At slice data memory RAM (128B/256B),it use not depositting not can reading /data that write, such as result not middle of operation, final result and data wanted to show, etc. ( 3) Procedure memory ROM/EPROM (4KB/8KB ), is used to preserve the procedure , some initial data and form in slice. But does not take ROM/EPROM within some one-chip computers, such as 8031 , 8032, 80C ,etc.. ( 4) Four 8 run side by side I/O interface P0 four P3, each mouth can use as introduction , may use as exporting too. ( 5) Two timer / counter, each timer / counter may set up and count in the way, used to count to the external incident, can set up into a timing way too, and can according to count or result of timing realize the control of the computer. ( 6) Five cut off cutting off the control system of the source . ( 7) One all duplexing serial I/O mouth of UART (universal asynchronous receiver/transmitter (UART) ), is it realize one-chip computer or one-chip computer and serial
communication of computer to use for. ( 8) Stretch oscillator and clock produce circuit, quartz crystal finely tune electric capacity need outer. Allow oscillation frequency as 12 megahertas now at most. Every the above-mentioned part was joined through the inside data bus .Among them, CPU is a core of the one-chip computer, it is the control of the computer and command centre, made up of such parts as arithmetic unit and controller , etc.. The arithmetic unit can carry on 8 persons of arithmetic operation and unit ALU of logic operation while including one, the 1 storing device temporarilies of 8, storing device 2 temporarily, 8's accumulation device ACC, register B and procedure state register PSW, etc. Person who accumulate ACC count by 2 input ends entered of checking etc. temporarily as one operation often, come from person who store 1 operation is it is it make operation to go on to count temporarily , operation result and loopback ACC with another one. In addition, ACC is often regarded as the transfer station of data transmission on 8051 inside . The same as general microprocessor, it is the busiest register. Help remembering that agreeing with A expresses in the order. The controller includes the procedure counter , the order is depositted, the order decipher, the oscillator and timing circuit, etc. The procedure counter is made up of counter of 8 for two, amounts to 16. It is a byte address counter of the procedure in fact, the content is the next IA that will carried out in PC. The content which changes it can change the direction that the procedure carries out . Shake the circuit in 8051 one-chip computers, only need outer quartz crystal and frequency to finely tune the electric capacity, its frequency range is its 12MHZ of 1.2MHZ. This pulse signal, as 8051 basic beats of working, namely the minimum unit of time. 8051 is the same as other computers, the work in harmony under the control of the basic beat, just like an orchestra according to the beat play that is commanded.
译文：
集成电路
在电子学中，集成电路（亦称为ＩＣ，微型电路，微型芯片等），是一种制造于半导体材料薄膜衬底表面的小型化电路（主要包括半导体设备和无源器件）。

集成电路普遍应用于当今的电子设备中，彻底改变了电子世界。

实验表明半导体器件可以实现真空管的功能。

20世纪中期半导体制造技术的进步，使得集成电路成为可能。

相对于手工组装电路使用分立的电子元器件，集成电路把大量的微晶体管集成到一个小芯片，是一个巨大的进步。

集成电路的大规模生产性，可靠性和模块化，使得应用标准化IC的电路设计迅速取代了使用离散晶体管的电路设计。

集成电路相对于离散晶体管有两个主要的优势：成本和性能。

成本低是由于芯片把所有的元件通过照相平版技术，作为一个单位印刷，而不是在一个时间只制作一个晶体管。

此外，实现同样的功能，集成电路使用的电子材料比分立式的要少得多。

性能高是由于元件快速开关，消耗更低能量（相对于分立式元器件），因为元件很小且彼此靠得很近。

2006年，芯片面积从几平方毫米到约350 mm²，每mm²可以集成达到一百万个晶体管。

最先进的集成电路是微处理器或称核,它用于控制大到电脑小到手机或数字微波炉等。

数字存储芯片和ASIC是其它系列集成电路家族的例子，它们对于现代信息社会非常重要。

虽然单独设计开发一个复杂的集成电路的成本非常高，但当分散到数以百万计的产品上，每个IC的成本就很小了。

IC的性能很高，因为微小元件带来很短的线路，使得低功率逻辑电路（如CMOS电路）可以应用于高速开关。

近些年来，IC的尺寸不断微型化，使得单个芯片可以封装更多的电路。

这样可以增加每单位面积上元器件得的数量，降低了成本和增加了功能。

由摩尔定律的现代释义可知，集成电路中的晶体管数量，每两年增加一倍。

总之，随着外形尺寸缩小，几乎所有的性能指标都得到了改善——单位成本和开关功耗下降了，运行速度提高了。

但是，纳米级的IC并非没有问题，其中最主要的问题是泄漏电流（参见亚阈值泄漏）。

虽然这个问题不能完全克服，但至少可以通过引入高阻抗的电导来改善其性能。

由于用户对IC 的运行速度和功率消耗非常敏感，各生产商在如何开发运用更好的技术上存在着激烈的竞争。

这个过程以及在未来几年可能取得的进步，在国际半导体技术蓝图（ITRS）中有很好的描述。

仅在其发明后的半个世纪，集成电路变得无处不在。

电脑，手机和其他数码产品成为现代社会不可缺少的一部分。

现代计算，通信，制造和交通系统，包括互联网，全都依赖于集成电路的存在。

IC可分为模拟IC，数字IC和数模混合IC（同一块IC上既有模拟电路也有数字电路）。

数字IC在几平方毫米上可以集成上百万个逻辑门，多谐振荡器，多路复用器和其它电路。

微型化的电路使得IC较板级电路运行速度更快，耗能更小，生产成本更低。

这些数字IC, 以微处理器，数字信号处理器（DSP）和微控制器为代表，工作中使用二进制，处理1和0信号。

模拟IC，例如传感器，电源控制电路和运放，用于处理连续的模拟信号，可以完成放大，滤波，解调，混频等功能。

IC中也可以集成模拟电路和数字电路，实现如数/模转换(D/A)或模/数转换(A/D)的功能。

这种电路的尺寸更小，成本更低，但必须注意信号干扰。

19世纪30年代始，研究者如贝尔实验室的William Shockley通过研究，认为在化学元素周期表中的半导体硅元素是构成固态真空管最可能的原料。

从氧化铜到锗，再到硅，原料在19世纪40年代到50年代被系统的研究。

今天，尽管元素周期表中的一些III-V价化合物如砷化镓有特殊用途，如应用于发光二极管，激光，太阳能电池和超高速集成电路，但单晶硅仍是集成电路的主流基层。

人们花了数十年的时间来完善在半导体材料的晶体结构中创造无缺陷晶体的方法。

半导体IC是逐层制造的，其构造工艺过程包括以下关键步骤：成像，沉积，蚀刻，在其构造过程辅以掺杂及清洁。

IC 由很多重叠的层组成，每层由影像技术定义，通常用不同的颜色表示。

有些层标记出不同的掺杂剂在基板上的分布（称为扩散层），有些层定义哪里有额外的离子注入（称为灌输层），有些层定义导体的特性（多晶硅层或金属层），有些层定义传导层之间的连接（过孔层或连接层）。

所有的IC元件皆由这些层的特定组合构成。

在制造一个自排列CMOS的过程中，门层（多晶硅或金属）穿过扩散层形成晶体管。

因为CMOS器件只引导电流在逻辑门之间转换，因而CMOS器件比双级元件消耗的电流少很多。

随机存取存储器（random access memory）是最常见的集成电路，所以密度最高的设备是存储器，即使是微处理器上也有集成存储器。

尽管存储器结构非常复杂——几十年来，芯片的宽度一直在减少，但芯片的层依然比其宽度薄得多。

其层的制作过程非常象照相过程，虽然可见光谱中的光波不能用来曝光元件层，因为他们太大了。

因而采用高频光子（通常是紫外线）来创造层的图案。

因为每个特征都非常小，所以对于一个正在调试制造过程的过程工程师来说，电子显微镜是必要的工具。

最早的集成电路使用陶瓷扁平封装，这种封装由于其可靠性高和尺寸小，军方多年来一直使用。

商用电路封装很快就发展到双列直插式封裝（dual in-line package DIP）,开始是陶瓷，之后是塑料。

20世纪80年代，VLSI电路的针脚超过了DIP封装的应用限制，导致插针网格阵列和leadless chip carrier（LCC）的出现。

贴片式的封装在20世纪80年代初期出现，在80年代后期开始流行。

贴片式使用更小的脚间距，引脚形状为海鸥翼型或J型。

以Small-Outline Integrated Circuit（SOIC）为例，贴片式占用面积比DIP少30－50％，厚度少70％。

这种封装在两个长边有海鸥翼型引脚突出，引脚间距为0.05英寸。

90年代后期，PQFP和TSOP封装成为高引脚数器件最普遍的封装形式，尽管PGA封装仍常用于高端微处理器。

英特尔和AMD目前正把高端微处理器从PGA封装过渡到（LGA）封装。

球栅阵列（BGA）封装出现于20世纪70年代。

倒装芯片球栅阵列封装（FCBGA）始发展于20世纪90年代，这种封装形式允许更高的引脚数。

大多数集成电路都足够大以包含识别信息，一般包括四个部分：制造商的名称或标志，零件编号，生产批号和/或序列号以及标识芯片制造日期的4位数字代码。

面积极小的贴片式封装芯片往往需要用该芯片上的一个数字到生产商的列表中查找该芯片的特点。

芯片制造日期通常表示为两位数的年份加两位数字的星期代码。

例如，芯片上的代码8341表示该芯片生产于1983年的第41周，或着说大约在1983年10月生产。

51系列单片机的功能和结构：
MCS - 51系列单片机具有一个单芯片电脑的结构和功能，它是英特尔公司生产的系列产品的名称。

这家公司在1976年推出8位的MCS - 48系列单芯片计算机后，于1980年推出的8位的MCS - 51系列单芯片计算机。

诸如此类的单芯片电脑有很多种，如8051，8031，8751，80C51BH，80C31BH等，其基本组成，基本性能和指令系统都是相同的。

8051是51系列单芯片电脑的代表。

一个单芯片的计算机系统由以下几个部分组成：（1）一个8位的微处理器（CPU）。

（2）片内数据存储器RAM（128B/256B），它只读/写数据，如结果不在操作过程中，最终结果要显示数据（3）程序存储器ROM/ EPROM（4KB/8KB），是用来保存程序，一些初步的数据和切片的形式。

但一些单芯片电脑没有考虑ROM / EPROM，如8031，8032，80C51等等。

（4）4个8路运行的I / O接口，P0，P1,P2,P3，每口可以用作入口，也可以用作出口。

（5）两个定时/计数器，每个定时/计数器可设置和计数的方式，用来计数外部事件，可以设置成定时方式也可以根据计算结果或定时控制实现计算机。

（6）5个中断（7）一个全双工串行的I / UART（通用异步接收器I口/发送器（UART）），它是实现单芯片电脑或单芯片计算机和计算机的串行通信使用。

（8）振荡器和时钟产生电路，需要考虑石英晶体微调能力。

允许振荡频率为12MHz，每一个上述的部分都是通过内部数据总线连接。

其中CPU是一个芯片计算机的核心，它是计算机的指挥中心，是由算术单元和控制器等部分组成。

算术单元可以进行8位算术运算和逻辑运算， ALU单元是其中一种运算器，1 8个存储设备，暂存设备的积累设备进行协调，程序状态寄存器PSW积累了2个输入端的计数等检查暂时作为一个操作往往由人来操作谁储存1输入的是它使操作去上暂时计数，另有一个操作的结果，回环协调。

此外，协调往往是作为对8051内的数据传输转运站考虑。

作为一般的微处理器，它是最繁忙的，帮助记住和同意与其的顺序表示。

该控制器包括程序计数器，解密的顺序。

振荡器和定时电路等的程序计数器是一个由8个计数器为2，总计 16位。

这是一个字节的地址，其实程序计数器，
是在个人电脑内进行。

从而改变它的内容也可以改变程序的进行方向。

在8051的单芯片电脑的电路中，只需要外部石英晶体和频率微调电容，其频率范围为1.2MHz到12MHz。

这种脉冲信号，作为8051的工作的单位时间的最低基本节奏。

8051是跟其他电脑一样，在节拍控制的控制下完成本工作，就像一个管弦乐队，根据节拍的指挥来演奏。