毕业设计（论文）-电梯自动控制模型设计.doc

毕业设计说明书(毕业实践任务书)43课题名称 电梯自动控制模型 课题需要完成的任务：1.根据技术指标进行可行性方案分析及方案论述。2.硬件的框图及电路设计。3.传感器、显示器件、各主要器件、单元电路等的选用方案，性能分析及功能介绍。4.设计硬件电路的电路图。5.软件部分流程图及相关程序设计。6.毕业设计小结。课题计划：2.273.10 查资料，进行初步方案设计。3.113.18 设计最佳方案；设计硬件电路，。3.194.10 编制程序，写毕业论文。4.114.20 修改、完善毕业论文，并做答辩准备。计划答辩时间：4.22电子信息技术系 （部、分院） 2007 年 4 月 18 日无锡职业技术学院毕业设计说明书(毕业实践调研报告)无锡职业技术学院毕业设计说明书(英文翻译)英文diode characteristic and applicationin all electronic circuit, all must use nearly to the semiconductor diode, it is playing the vital role in many electric circuits, it is born one of earliest semiconductor devices, its application extremely is also widespread.diode principle of workthe crystal diode is the p-n knot which forms by the p semiconductor and the n semiconductor, forms the space charge level in its contact surface place two side, and constructs from constructs the electric field. when does not have the external voltage, because p-n ties the diffusion current which two side loads currents concentration difference causes and from constructs the drifting electric current which the electric field causes to be equal but is at the electric equilibrium condition.when the outside has the forward voltage bias, the outside electric field and from constructed the electric field to damp mutually disappears the function to cause the current carrier the diffusion current increase to cause to the electric current.when the outside has the reverse voltage bias, the outside electric field and from constructs the electric field further to strengthen, forms in the certainly reverse voltage scope reverse saturation current i0 which has nothing to do with with the reverse bias voltage value.when sur- reverse voltage as high as certain degree, p-n ties in the space charge level the electric-field intensity to achieve the marginal value produces the current carrier to multiply the process, produces the massive electron-hole pairs, has produced the value very big reverse striking current, is called the diode to penetrate the phenomenon.diode typethe diode type has very much, according to semiconducting material which uses, may divide into the germanium diode (getube) and silicon diode (si tube). according to its different use, may divide into the detector diode, the rectification diode, the zener diode, the switch diode and so on. according to looks after the core structure, also may divide into the contact diode, the surface contact diode and the plane diode. the contact diode is presses with a very thin tinsel in the bright and clean semiconductor chip surface, passes by the pulse electric current, makes to touch a silk end and the chip reliably agglutinates in the same place, forms the pn knot. because is a contact, only allows through the small electric current (not to surpass several dozens milliamperes), is suitable in the high frequency undercurrent electric circuit, like radio detection and so on.surface contact diode pn knot area big, allows (several to arrive safely through the big electric current several dozens is peaceful), mainly uses in the alternating current transforming the direct current the rectification in the electric circuit.the plane diode is the silicon diode which one kind specially makes, it not only can through the big electric current, moreover the performance stable is reliable, uses in the switch, the pulse and the high-frequency circuit.diode electric conduction characteristicthe diode most important characteristic is the folk remedy guide electric properties. in the electric circuit, the electric current only can from the diode positive electrode inflow, the cathode flow out. under explains the diode through the simple experiment to the characteristic and the reverse characteristic.1、characteristic in the electronic circuit, meets the diode positive electrode in the high electric potential end, the cathode meets in the cold end, the diode can lead passes, this connection way, is called to the bias. must explain, when adds in the diode beginnings and ends forward voltage very hour, the diode still could not lead passes, flows the diode to be extremely weak to the electric current. only then when the forward voltage achieved some value (this value is called the threshold voltage, the germanium governs and restrains is0.2vthe silicon governs and restrains is0.6v) later, the diode will be able honest to lead passes. after leads passes the diode beginnings and ends voltage basically maintains (the germanium to govern and restrain invariablely is0.3vthe silicon governs and restrains is0.7v) is called the diode to the pressure drop.2、reverse characteristicin the electronic circuit, the diode positive electrode meets in the cold end, the cathode meets in the high electric potential end, this time in the diode nearly does not have the electric current to flow, this time the diode is at the closure condition, this connection way, is called the reverse bias. when the diode is in the reverse bias, still could have the weak reverse electrical current to flow the diode, was called leaks the electric current. when the diode beginnings and ends reverse voltage increases to some value, the reverse electricity inoperables for lack of a quorum increases suddenly, the diode will lose the folk remedy to the electric conduction characteristic, this kind of condition will be called the diode penetrating.diode main parameteruses for to express the diode performance quality and the applicable scope technical specification, is called the diode the parameter. the different type diode has the different characteristic parameter. speaking of the beginner, must understand following several main parameters:1、volume correction to operating currentmost taisho which is refers to when diode long-term continuous working allows to pass to the magnitude of current. because electric current through pipe time can cause the tube core to give off heat, the temperature rise, the temperature surpasses the tolerance range (the silicon tube is140about, the germanium tube is90when about), can cause the tube core heat but to damage. therefore, in the diode use do not have to surpass the diode volume correction to the work magnitude of current. for example, commonly used in4,0014,007the germanium diode volume correction to the operating current is 1a。2、highest reverse working voltageadds when the diode beginnings and ends reverse voltage as high as a definite value, can penetrate the pipe, loses the unilateral conduction ability. in order to guarantee the use security, has stipulated the highest reverse working voltage value. for example, the in4001 diode reverse pressure resistance is 50v, the in4007 reverse pressure resistance is 1000v.3、reverse electrical currentthe reverse electrical current is refers to the diode in the stipulation temperature and under the highest reverse voltage function, has flowed the diode reverse electrical current. reverse electrical current smaller, the pipe single direction electric conductivity is better. the worth noting is the reverse electrical current and the temperature has close relationship, probably the temperature every time elevates 10, the reverse electrical current increases a time. for example 2ap1 germanium diode, in 25 oclock reverse electrical currents if is 250uatemperature increment to 35, the reverse electrical current will rise to 500ua, infer from this, when 75, its reverse electrical current has reached 8manot only has lost the folk remedy to the electric conduction characteristic, but also can cause the pipe heat but to damage. also like, the 2cp10 silicon diode, 25 oclock reverse electrical currents are only 5uatemperature increment to 75 oclock, reverse electrical current also only 160ua. therefore the silicon diode has the good stability compared to the germanium diode under the high temperature.detecting diode qualitythe beginner may use the avonmeter detecting diode performance under the extra-curricular condition the quality. before the test allocates move set clock for the avonmeter change-over switch the ohm files the rx1k files position (attention not to have first to use the rx1 files, in order to avoid electric current oversized burns out diode), will be then red, the black two tables pen short-circuits, carries on the ohm to adjust the zero.1、characteristic test(in table positive electrode) builds the avonmeter black table pen touches the diode the positive electrode, the red table pen (in table cathode) builds touches the diode the cathode. if the table needle does not suspend to 0 values but is stops in dial among, the by now resistance number was the diode forward resistance, the general forward resistance smaller was better. if the forward resistance is 0 values, explained the tube core short-circuits the damage, if the forward resistance approaches the infinity value, explained the tube core shuts. short-circuits the pipe which and shuts all not to be able to use.2、reverse characteristic testbuilds wan qiebiao red table pen touches the diode the positive electrode, the black table pen builds touches the diode the cathode, if the table needlework or approaches the infinity value in the infinity value, the pipe is qualified.diode application1、rectification diodeusing the diode unilateral conductivity, may the alternating current which changes in turn the direction transform the sole direction the pulsating direct current.2、on-off elementthe diode the resistance is very small under the forward voltage function, is at leads passes the condition, is equal switch which puts through in; under the reverse voltage function, the resistance is very big, is at the closure condition, is similar to switch which separates. using the diode switch characteristic, may compose each logic circuit.3、restricts the partafter the diode guide passes, it is being invariable (the silicon tube to the pressure drop basic maintenance is0.7vthe germanium tube is0.3v) . using this characteristic, the achievement restricts the part in the electric circuit, may limit the signal scope in the certain scope.4、continues flows the diodecontinues in in the switching power supply inductance and the relay equisignal load flows the function.5、detector diodein radio detecting action.6、changes accommodates the diodeuse in television high frequency tuner.the triode sentences the fracture definitelythe triode casts and the base pin distinction is electronic technology beginners basic skills, in order to help the reader rapidly to grasp measured sentences the method, the author summarizes four mnemonics: three inversions, looks for the base extremely; the pn knot, decides casts; along the arrow, deflects in a big way; measured does not permit, to move the mouth. under lets us carry on the explanation by the sentence.一、 three inversions, looks for the base extremelyas everybody knows that, the triode includes the semiconductor device which two pn ties. ties the connection way according to two pn to be different, may divide into npn and the pnp two kind of different electric conduction types triode, chart 1 is their electric circuit mark and the equivalent circuit.tests the triode to have to use amp the ohm to keep off, and the choice r100 or r1k keeps off the position. chart 2 drew the equivalent circuit which the amp ohm kept off. by the chart obviously, is in the table which the red table pen connects the battery cathode, the black table pen then is connecting in the table the battery positive electrode.supposes us not to know was measured the triode is npn pnp, also cannot distinguish clearly various base pins is any electrode. which base pin the test first step is judges is the base extremely. by now, we no matter what took two electrodes (for example these two electrodes were 1, 2), inverted with the amp two tables pens surveys it, the back-resistance, the observation table needle deflection angle; then, again takes 1, 32 electrodes and 2, 32 electrodes, inverts separately surveys them, the back-resistance, the observation table needle deflection angle. in these three inversions survey, inevitably some two measurement result close: namely in the inversion survey the table needle time deflects in a big way, time deflects slightly; is left over time is inevitably inverts around the survey the needle deflection angle all very small, this had not measured that base pin is the base which we must seek (the senate map-read 1, chart 2 is not extremely difficult to understand its truth).二、 the pn knot, decides castsafter discovers the triode the base extremely, we may act according to the base the direction which pn ties with other two electrodes between to determine the pipe extremely the electric conduction type (chart 1). the avonmeter black table pen contact base extremely, the red table pen contacts in other two electrodes no matter what an electrode, if the table needle deflection angle is very big, then explained was measured the triode is the npn tube; if the table needle deflection angle is very small, then was measured the tube is pnp.三、is suitable the arrow, deflects in a big wayhas discovered base extremely b, moreover two electrodes which are collecting electrode c, which is emitter electrode e?by now we might use to measure penetration electric current iceo method determination collecting electrode c and emitter electrode e.(1) regarding the npn triode, penetration electric current metering circuit like chart 3 shows. according to this principle, with the amp black, the red table pen inverts between the survey two-pole, back-resistance rce and rec, although in two surveys avonmeter needle deflection angle all very small, but carefully observes, the general meeting has a time of deflection angle to be slightly big, this time the electric current flows to certainly is: black table pen - c - b extremely - the e extremely - red table pen, the electric current flows to extremely happen to is consistent with the triode mark in arrow direction (along arrow), therefore this time black table pen meets certainly is collecting electrode c, the red table pen meets certainly is emitter electrode e.(2) regarding the pnp triode, the truth also is similar to npn, its electric current flows to certainly is: black table pen - e - b extremely - the c extremely - red table pen, its electric current flows to extremely is also consistent with the triode mark in arrow direction, therefore this time black table pen meets certainly is emitter electrode e, the red table pen meets certainly is collecting electrode c (the senate map-read 1, chart 3 may know).四、could not measure, moves the mouthif in is suitable the arrow, deflects in a big way in survey process around, if when inverts two surveys needle deflection too small with difficulty differentiates, wants to move the mouth. the concrete method is: in was suitable the arrow, deflects in a big way in two surveys, presses firmly between the fingers two tables pens and the base pin intersection separately with two hands, contains with the mouth (or resists base electrode b with tongue), still used to be suitable the arrow, deflected in a big way the distinction method then differentiated open set electrode c and emitter electrode e. human body plays to the direct current bias resistance role, the goal is causes the effect to be more obvious.中文二极管的特性与应用几乎在所有的电子电路中，都要用到半导体二极管，它在许多的电路中起着重要的作用，它是诞生最早的半导体器件之一，其应用也非常广泛。二极管的工作原理 晶体二极管为一个由p型半导体和n型半导体形成的p-n结，在其界面处两侧形成空间电荷层，并建有自建电场。当不存在外加电压时，由于p-n 结两边载流子浓度差引起的扩散电流和自建电场引起的漂移电流相等而处于电平衡状态。 当外界有正向电压偏置时，外界电场和自建电场的互相抑消作用使载流子的扩散电流增加引起了正向电流。 当外界有反向电压偏置时，外界电场和自建电场进一步加强，形成在一定反向电压范围内与反向偏置电压值无关的反向饱和电流i0。 当外加的反向电压高到一定程度时，p-n结空间电荷层中的电场强度达到临界值产生载流子的倍增过程，产生大量电子空穴对，产生了数值很大的反向击穿电流，称为二极管的击穿现象。二极管的类型 二极管种类有很多，按照所用的半导体材料，可分为锗二极管（ge管）和硅二极管（si管）。根据其不同用途，可分为检波二极管、整流二极管、稳压二极管、开关二极管等。按照管芯结构，又可分为点接触型二极管、面接触型二极管及平面型二极管。点接触型二极管是用一根很细的金属丝压在光洁的半导体晶片表面，通以脉冲电流，使触丝一端与晶片牢固地烧结在一起，形成一个“pn结”。由于是点接触，只允许通过较小的电流（不超过几十毫安），适用于高频小电流电路，如收音机的检波等。 面接触型二极管的“pn结”面积较大，允许通过较大的电流（几安到几十安），主要用于把交流电变换成直流电的“整流”电路中。 平面型二极管是一种特制的硅二极管，它不仅能通过较大的电流，而且性能稳定可靠，多用于开关、脉冲及高频电路中。二极管的导电特性 二极管最重要的特性就是单方向导电性。在电路中，电流只能从二极管的正极流入，负极流出。下面通过简单的实验说明二极管的正向特性和反向特性。1、正向特性 在电子电路中，将二极管的正极接在高电位端，负极接在低电位端，二极管就会导通，这种连接方式，称为正向偏置。必须说明，当加在二极管两端的正向电压很小时，二极管仍然不能导通，流过二极管的正向电流十分微弱。只有当正向电压达到某一数值（这一数值称为“门槛电压”，锗管约为0.2v，硅管约为0.6v）以后，二极管才能直正导通。导通后二极管两端的电压基本上保持不变（锗管约为0.3v，硅管约为0.7v），称为二极管的“正向压降”。2、反向特性 在电子电路中，二极管的正极接在低电位端，负极接在高电位端，此时二极管中几乎没有电流流过，此时二极管处于截止状态，这种连接方式，称为反向偏置。二极管处于反向偏置时，仍然会有微弱的反向电流流过二极管，称为漏电流。当二极管两端的反向电压增大到某一数值，反向电流会急剧增大，二极管将失去单方向导电特性，这种状态称为二极管的击穿。二极管的主要参数 用来表示二极管的性能好坏和适用范围的技术指标，称为二极管的参数。不同类型的二极管有不同的特性参数。对初学者而言，必须了解以下几个主要参数：1、额定正向工作电流 是指二极管长期连续工作时允许通过的最大正向电流值。因为电流通过管子时会使管芯发热，温度上升，温度超过容许限度（硅管为140左右，锗管为90左右）时，就会使管芯过热而损坏。所以，二极管使用中不要超过二极管额定正向工作电流值。例如，常用的in40014007型锗二极管的额定正向工作电流为1a。2、最高反向工作电压 加在二极管两端的反向电压高到一定值时，会将管子击穿，失去单向导电能力。为了保证使用安全，规定了最高反向工作电压值。例如，in4001二极管反向耐压为50v，in4007反向耐压为1000v。3、反向电流 反向电流是指二极管在规定的温度和最高反向电压作用下，流过二极管的反向电流。反向电流越小，管子的单方向导电性能越好。值得注意的是反向电流与温度有着密切的关系，大约温度每升高10，反向电流增大一倍。例如2ap1型锗二极管，在25时反向电流若为250ua，温度升高到35，反向电流将上升到500ua，依此类推，在75时，它的反向电流已达8ma，不仅失去了单方向导电特性，还会使管子过热而损坏。又如，2cp10型硅二极管，25时反向电流仅为5ua，温度升高到75时，反向电流也不过160ua。故硅二极管比锗二极管在高温下具有较好的稳定性。测试二极管的好坏 初学者在业余条件下可以使用万用表测试二极管性能的好坏。测试前先把万用表的转换开关拨到欧姆档的rx1k档位（注意不要使用rx1档，以免电流过大烧坏二极管），再将红、黑两根表笔短路，进行欧姆调零。1、正向特性测试 把万用表的黑表笔（表内正极）搭触二极管的正极，红表笔（表内负极）搭触二极管的负极。若表针不摆到0值而是停在标度盘的中间，这时的阻值就是二极管的正向电阻，一般正向电阻越小越好。若正向电阻为0值，说明管芯短路损坏，若正向电阻接近无穷大值，说明管芯断路。短路和断路的管子都不能使用。2、反向特性测试 把万且表的红表笔搭触二极管的正极，黑表笔搭触二极管的负极，若表针指在无穷大值或接近无穷大值，管子就是合格的。二极管的应用1、整流二极管 利用二极管单向导电性，可以把方向交替变化的交流电变换成单一方向的脉动直流电。2、开关元件 二极管在正向电压作用下电阻很小，处于导通状态，相当于一只接通的开关；在反向电压作用下，电