电子专业英语part1

1、English for Electronics & Information电子信息专业英语Part1 ElectronicsPart2 CommunicationsPart1 ElectronicsUnit 1 The Development of ElectronicsUnit 2 Resistor, Capacitor and InductorUnit 3 CircuitsUnit 4 AmplifierUnit 6 Pulse Digital CircuitEXERCISEUnit 1 The Development of Electronics电子学的发展电子学的发展电学电学经

2、典物理学经典物理学的一个分支的一个分支电子学电子学 基于电学中基于电学中的电磁学与电的电磁学与电工学发展起来工学发展起来electricityelectronics计算机计算机控制系统控制系统通信通信computercontrol systemcommunication应用领域应用领域 Electronics is a part of the larger field of electricity. The basic principles of electricity are also common to electronics. Modern advances in the fields

3、of computer, control system, communications have a close relationship with electronics.电子领域：电子管，晶体管，集成电路等发展对其起着重要作用。电子领域：电子管，晶体管，集成电路等发展对其起着重要作用。电子管电子管晶体管晶体管集成电路集成电路electron tubetransistorintegrated circuit The field of electronics includes the electron tube, transistor, integrated circuit and so on

4、.1883年：电子学始于年：电子学始于“爱迪生效应爱迪生效应”，爱迪生研究电灯材料，爱迪生研究电灯材料时发现了真空二极管。时发现了真空二极管。1905年：佛莱明发明第一个二极管年：佛莱明发明第一个二极管真空二极管真空二极管 Vacuum diode真空二极管的特点：真空二极管的特点： （1）非线性非线性 （2）单向导电单向导电 （3）不能）不能放大信号放大信号nonlinearunilateral electricalamplification of a signal Electronics began in 1883, when Thomas Edison discovered the va

5、cuum diode as part of his research on materials for a practical electric light. This first electronic device exhibited a nonlinear, unilateral electrical characteristic but was not capable of producing amplification of a signal. In 1905 Fleming produced the first diode.1906年，德年，德.福雷斯特研制第一个三极管福雷斯特研制第

6、一个三极管三极管二极管取代应用：通信工业如收音应用：通信工业如收音机、电视等机、电视等application : communication industry, radio, televisiondiodetriode In 1906 Deforest made the first triode in the United States. The widespread applications of vacuum tubes during that time period were in the communications industry, first in radio and later

7、 in television. The use of vacuum tubes declined rapidly when a semiconductor device was invented that could perform many of the functions previously associated with vacuum tubes.数字积分计算机数字积分计算机：第一个大型数字电子系统：第一个大型数字电子系统的的真空管真空管电路，电路，计算机工业计算机工业的先驱。的先驱。数字积分计算机：electronic numerical integrator and compute

8、r (ENIAC) The first large digital electronic system was a special-purpose vacuum tube circuit called the electronic numerical integrator and computer (ENIAC). The ENIAC was the forerunner of the computer industry.真 空 管 ： vacuum tube计算机工业： computer industry晶体管早期早期：锗材料材料近期近期：硅transistorgermaniumsilico

9、n应用：应用：袖珍调幅收音机Portable AM ( amplitude modulation) broadcast receivers1948年：晶体管问世，对电子学具有重大意义。年：晶体管问世，对电子学具有重大意义。 The transistor was invented in 1948 and made a significant contribution to electronics. The early transistors were made from germanium. The most visible application of these devices was in

10、 small, portable AM broadcast receivers. Silicon transistors began to replace germanium in the late 1950s.数字逻辑器件集成电路大型集成电路超大型集成电路digital logicintegrated circuitlarge-scale integration（LSI）Very large-scale integration（VLSI） The commercial success of the integrated circuit industry was based on standa

11、rd products representing digital logic families. The integrated circuit industry was moving from the era of small-scale circuits to large-scale integration (LSI). As the decade of the 1970s came to a close, a new era in integrated circuits was beginning. This era is characterized by the inclusion of

12、 larger and larger numbers of components in a single circuit, and it is called very large-scale integration (VLSI). Electronic technology is developing rapidly in the world. And electronics industry is equipped to make yet another giant step forward.Unit 2 Resistor, Capacitor and Inductor电阻器、电容器和电感器

13、电路元件：电阻、电感、电容等电路元件：电阻、电感、电容等电阻电阻电容电容电感电感resistorcapacitorinductor Although resistors, capacitors and inductors form important elements in electronic circuitry, it is essential to know something about resistance, capacitance and inductance.abUabIR电阻分类：1、固定电阻和可变电阻2、线性电阻和非线性电阻欧姆定律： UabIRUab：电压降I ：电流R ：

14、电阻，单位为欧姆电阻器：它是一个二端元件two-terminal elementOhms Lawvoltage dropcurrentohmfixed resistor, variable resistorlinear and nonlinear 一、电阻器及电阻一、电阻器及电阻resistor A resistor is a two-terminal element. Between its terminals it exhibits a voltage drop which is directly proportional to the current passing through it

15、. We specify the size of the resistor in ohms, which is the ratio of voltage to current. This relationship between voltage and current, called Ohms Law, can be stated in an equation V=IR. Resistors may be classified as fixed or variable in their type and also as linear and nonlinear.电阻的概念：对电流的阻力为电阻的

16、概念：对电流的阻力为电阻电阻。单位符号为。单位符号为。1的定义：当加在的定义：当加在导体导体上的电压为上的电压为1V时，将导体的电时，将导体的电 流限制为流限制为1A所需要的所需要的电抗电抗值。值。 Resistance is the opposition to the flow of current and is represented by the letter symbol R. The unit of resistance is the ohm, expressed by using (). One ohm is defined as that amount of resistance

17、 that will limit the current in a conductor to one ampere when the voltage applied to the conductor is one volt. Larger amount of resistance are commonly expressed in kilo-ohm (k) and in mega-ohm (M).resistanceconductorReactance二、电容器及电容二、电容器及电容电容器的概念：可以将电容器的概念：可以将电能电能存储在电场中的器件称为电存储在电场中的器件称为电容器。容器。电容

18、器按介质分类纸玻璃陶瓷capacitorpaperglassceramicdielectricelectrical energy Electrical energy can be stored in an electric field. The device capable of doing this is called a capacitor or a condenser. Capacitors are generally divided into classes according to their dielectric, e.g. paper, glass, ceramic, etc.a

19、bcet cetra(=and so on)for example电容器的特点：电容器的特点：1、电动势电动势越大，电容器存储的越大，电容器存储的电荷电荷就越多。就越多。2、电容器的、电容器的容量容量越大越大频率频率越高，越高，容抗容抗也就越小。也就越小。Electromotive forceelectricitycapacityfrequencycapacity reactance The larger is the electromotive force, the more electricity the capacitor stores. The greater is the capac

20、ity of the capacitor, and the higher is the frequency, the lower is the capacity reactance.The + 比较级，the比较级：表示“越越”电容的概念：电容器存储电容的能力叫电容的概念：电容器存储电容的能力叫电容。电容。电容的特点：电容的特点： 1、电容从来都不是、电容从来都不是常数常数，除非在，除非在固定的条件固定的条件下。下。 2、电容的单位为、电容的单位为法拉法拉（F）。一般用）。一般用微法微法，微微法微微法。constantfixed conditionfaradmicro farad1F=106M

21、F=1012MMf(PF) The ability of a capacitor to store electrical energy is termed capacitance. It is important to remember that capacitance is never constant, except under certain fixed conditions. It is measured in farads (F). However, farad is too large a unit to be used in radio calculation, so micro

22、farad and the micro microfarad are generally used.capacitancemicro microfaradpicofarad三、电感器及电感三、电感器及电感电感器：电感器是由电线绕着一个合适的模子而成的一个线圈。电感器的特点：电感器上的电压与电流的时间变化率成正比。 这个常数称为电感（L），单位为亨利（H）。moldcoilbe directly proportional toinductancehenry It is well known that inductors are one of building blocks in electron

23、ics. An inductor is formed by winding wire around a suitable mold to form a coil. In an inductor, the voltage is directly proportional to the time rate of change in the current. The constant of proportional is called inductance (L) and measured in Henries (H).inductorabL电感器与电容的异同：相同点：都能把供给它的能量储存起来。不

24、同点：电感储存磁场能，电容储存电场能。energymagnetic field energyelectric field energy An inductor, like a capacitor, stores the energy supplied to it, but it stores energy in the form of a magnetic rather than an electric fieldand not:而不是，而非电感：阻止流过线圈的电流发生变化的性质称为电感。电感的特点：同一频率下较小的电感对电流阻力较小。并不像电阻一样对所有电流都有阻力。opposeproper

25、tyinductance All coils have inductance. Inductance is the property of opposing any change if current flowing through a coil. A small inductance would provide less opposition at the same frequency. Inductance differs from resistance in that resistance offers an opposition to all current.becauseExerci

26、se Try to match the flowing columns:fixed resistorthe amount of resistanceelectric fieldcapacity reactancethe opposition to the currentnonlinear resistorthe constant of proportionalitya two-terminal element非线性电阻对电流的阻力一个二端元件比例常数电阻值固定电阻容抗电场Unit 3 Circuits电路 开 关 干 电 池 灯 泡 电源控制器件负载导线power supplywirecont

27、rol deviceload电路1、电源： 2、导体或导线3、控制器件： 4、负载source or power supplybatteryconductor, wirecontrol deviceswitchload如电池如开关组成如电灯、电阻器、电动机lampresistormotor An electric circuit often consists of four parts: a source of power supply such as battery, the conductors or wires, the control device such as a switch,

28、and the load. The load is a device or a machine. Within the load the actual energy conversion takes place. The lamp, the resistor and the motor are common examples of electric loads.电路的概念：有电子不断流动的导体和电动势源的组合 Any combination of a conductor and of a source of e. m. f. which permits electrons to travel

29、round in a continuous stream is called an electric circuit. electromotive forceelectric circuit干电池电灯dry cell负极： 正极： negative terminal positive terminal 再生的、反馈的： regenerative A lamp connected across a dry cell is an example of a simple electrical circuit. Current flows from the negative(-) terminal o

30、f the cell, through a lamp, to the positive(+) terminal; and the action of the cell is such that it provides a “regenerative” path for the flow of electrons to be maintained through the negative terminal once again.通路（闭合电路） 开路 （断路） closed circuitopen circuit As long as this electrical pathway remain

31、s unbroken at any point, it is a closed circuit; and current flows. But if the pathway be ever broken, it becomes at once an open circuit; and no current can flow.电路按连接方式不同，可分为串联电路和并联电路series circuitparallel circuit Series circuits and parallel circuits are two main types of circuit connection. 串联电路

32、： 当电器元件连接时，电流没有分流，这种连接称为串联。特 点：每一处电流都相等。 Series circuits and parallel circuits are two main types of circuit connection. When electrical devices are connected so that the current is not divided at any point, they are said to be connected in series. The current in every part of this kind of circuit i

33、s the same. As a matter of fact, in everyday electric work we very often deal with circuit where the current branches between two or more paths. In ordinary house lighting, for instance, lamps are connected in parallel, each lamp filament representing an independent path from the minus main wire to

34、the plus wire. In parallel circuits the total current is equal to the sum of all the currents that are passing through the branches of that of another.for example并联电路： 含有两个或两个以上支路的电路，这种连接称为并联。特 点：总电流量等于各支路电流总和许多实用电路是串并联的，这种电路能够把串联电路的不同电压与并联电路的不同电流特征结合在一个网路内。当负载对同一个电源要求有不同的电压和电流时，这种电路就特别有用。实用电路:Pract

35、ical circuit串并联电路:series-parallel circuit Many practical circuits are arranged in series-parallel. Such circuits make it possible to combine the different voltage characteristic of a series circuit with the different current characteristic of a parallel circuit within a single network. This conditio

36、n is particularly advantageous when it is necessary to operate loads that have different voltage and current requirements from the same source of energy.Exercise: Try to match the following columns:a closed circuitnegativebatteryan open circuitpositiveas a matter of factconsist of minuscellbe compos

37、ed ofa circuit which was brokenin facta circuit that the current can flow throughplusUnit 4 Amplifier放大器放大器amplifierAn amplifier increases the magnitude of ,or amplifiers, an electric signal. The signal may be derived, for example, from a TV antenna. Of all components, the amplifier is by far the mo

38、st widely used building block in electronics systems.放大器能够增强即放大电信号。例如，这种信号可以来自电视天线。在所有的电子元件中，放大器在电子系统中是使用最广泛的部件。电信号电视天线电子系统electric signalTV antennaelectronics system放大器可用框图表示（如图4-1）。图中参数如下：输入信号电压：Es输入信号电流：Is负载电阻： RL，跨接在输出两端输入信号输出信号负载电阻input signaloutput signalload resistorAn amplifier may be repres

39、ented by simple block diagram of Fig.4-1. The input signal voltage is denoted by Es, and the input signal current is denoted by Is. Across the output terminals is load resistor RL.figure框图block diagramResistance RL may represent, for example, the resistance of a loudspeaker coil, a motor winding, or

40、 the input of a connected amplifier stage. Voltage E0 is the output (load) voltage, and current I0 the output (load) current. Symbols PI and P0 are the input and output signal powers, respectively.输出电压：Eo输出电流：Io输入信号功率：PI输出信号功率： Po电阻RL：可以是扬声器线圈的电阻、电动机的线组或者所连接放大级的输入。扬声器电动机放大级输入信号功率loudspeakermotorampl

41、ifier stageinput signal power1、电压放大器： 2、电流放大器:3、功率放大器Voltage amplifier放大电压信号放大电流信号4、脉冲放大器 5、运算放大器 放大器current amplifierpower amplifierpulse amplifieroperational amplifierThere are different kinds of amplifiers such as voltage amplifier, current amplifier, pulse amplifier and operational amplifier, et

42、c. If the amplifier is optimized to amplify voltage signals ,it is called a voltage amplifier. For current signals, it is referred to as a current amplifier, If it is to develop output power of one watt or more, it is generally classified as a power amplifier. 信号类型放大器信号振幅1、小信号放大器： 2、大信号放大器:放大微伏级和毫伏级

43、信号；常用代数学方法分析放大较大信号；常用图解法分析Another method of classification is based on the amplitude of signals. For small signals, in the order typically of microvolts and millivolts, the amplifier may be classified as small-signal, and for larger signals as a large-signal amplifier. Simple algebra is all that is

44、required for calculating the performance of small-signal amplifiers. Graphical methods, however, are generally used in the analysis of large-signal amplifiers.amplitudesmall-signal amplifierlarge-signal amplifieralgebragraphical methodswhat放大器相移情况phase shift1、甲类放大：负载电流相移360 2、乙类放大：负载电流相移180 3、甲、乙类放大

45、：负载电流180但3604、丙类放大：负载电流180class A operationclass B operationclass AB operationclass C operation负载电流load current flow正弦波：sine wave Amplifiers are also classified in terms of load current flow. Fig.4-2 shows the classes of amplifier operation. Fig.4-2a shows one cycle (360) of a sine wave input signal

46、 to an amplifier. If the load current also flows for 360, as indicated in Fig.4-2b, the amplifier is operating as class A. Class B operation, illustrated in Fig.4-2c, exists when the load current flows for only 180. If the load current flows for more than 180but less than 360, class AB operation is

47、realized (Fig.4-2d). Class C operation is obtained if the load current flows for less than 180(Fig.4-2e).Class A operation is used for small-signal and single-transistor (referred to as single-ended) power amplifiers. And for class B or AB operation the amplifier contains two transistors, referred t

48、o as a push-pull amplifier. Class C operation is often used in the amplification of r-f signals in a circuit containing a tuned load.各类放大器的功能：1、甲类用于小信号和单管（或单端）功率放大；2、作乙类放大或甲乙类放大时，放大器有两个晶体管成为推挽放大；3、丙类放大常用在调谐负载的电路中放大射频信号；single-transistorsingle-endedpush-pull amplifiertuned loadr-f signalradio-frequen

49、cy signalAmplifiers are also classified according to their intended operation. Examples include audio, r-f, video, microwave, and pulse amplifiers.放大器也可按其工作类型来分类。 例如：音频放大器 射频放大器 视频放大器 微波放大器 脉冲放大器audio amplifierr-f amplifiervideo amplifiermicrowave amplifierpulse amplifierThe performance of amplifier

50、s is characterized by the following terms: voltage gain, current gain, power gain, input resistance, output resistance, bandwidth, distortion.放大器性能的术语有： 电压增益、 电流增益、 功率增益、 输入电阻、 输出电阻、 带宽、 失真。voltage gaincurrent gainpower gaininput resistanceoutput resistancebandwidthdistortionTranslate :1、调谐负载2、负载电阻3

51、、负载电流4、电压放大器5、推挽放大器6、脉冲放大器7、功率放大器8、电流放大器pulse amplifierload resistorload currentpush-pull amplifierVoltage amplifierpower amplifiera tuned loadcurrent amplifierUnit 6 Pulse Digital Circuit数字脉冲电路Nowadays all of us are familiar with the computer. The ability of a computer to solve a problem depends up

52、on its ability to make certain decision as it progresses through the various steps of the problem. For example, the computer must make decisions (called logical decisions) as to whether a number is positive, whether a certain number is larger or smaller than another, or whether a portion of the prob

53、lem is finished so that the computer may proceed to the next portion. 计算机解答问题的能力取决于它对问题的各个步骤进行判断的能力。例如：计算机必须判断一个数是不是正的，某个数比另一个数大还是小，或者问题的某一部分是否已经完成。取决于：depend upon 正的：positive 部分：portion The various circuits that enable the computer to make its decisions are called logic circuits, or digital circuit

54、s. 数字电路（逻辑电路）的概念：使计算机能进行判断的各种电路。digital circuits, or logic circuits The term digital circuit is used to describe those circuit systems which primarily operate with the use of only two different voltage levels or two other binary conditions or states. 数字电路这个术语被用来描述仅用两种不同电压电平，即两种不同二进制状态进行工作的电路系统。circu

55、it systemsbinaryThe two different states by which digital circuits operate may be of several forms. They can , in the most simple form, consist of the opening and closing of a switch. In this case, the closed-switch condition can be represented by 1 and the open-switch condition by 0. Likewise, the

56、lighted lamp can be considered as being in the 1 condition when the switch is closed, while the unlighted lamp can be considered as being in the 0 condition when the switch is open.开关打开开关闭合灯亮灯灭“1”“0”数字电路switchlampA very common method of digital operation is achieved by using voltage pulse. A pulse i

57、s defined as a rapid change from one voltage level to another and then a rapid return to the original level. The duration of time at the second level is usually quite short compared with the time at the first level. 数字电路工作的最普通的方法是采用电压脉冲进行的。 脉冲的定义：从一个电平迅速变化到另一个电平，然后又快速回到初始电平。脉冲： pulse电平： voltage leve

58、l The pulse is made up of a positive step and a negative step. (If the step is above the baseline, it is called a positive step, if it is below the baseline it is called negative.) 一个脉冲由一个正阶跃和一个负阶跃组成。（如果阶跃位于基线之上，那么它被称为正阶跃；如果在基线之下，则被称为负阶跃。）正阶跃：Positive step负阶跃：negative step基线：baselineIf the positive

59、step comes first it is a positive pulse and if the negative step is first it is a negative pulse. The presence of a positive pulse can be represented by 1 and the absence of a pulse by 0. 如果正阶跃首先出现，脉冲是正脉冲，相反，如果负阶跃首先出现，脉冲就是负脉冲。有正脉冲存在，用“1”表示，没有正脉冲存在用“0”表示。正脉冲：Positive pulse负脉冲：negative pulse 电子仪器中用到的脉

60、冲波形有：方波、锯齿形波、微分波形等。 若用方波信号，正脉冲可代表“1”，负脉冲代表“0”。脉冲波形：Pulse waveform方波形： rectangular waveform锯齿波形： sawtooth waveform微分波形： differentiated waveformPulses are various in forms. Pulse waveforms used in electronic devices are: rectangular waveform, sawtooth waveform, differentiated waveform and so on. With a sq