簡(jiǎn)易模擬集成萬(wàn)用表

20132014

學(xué)年

第2

學(xué)期《

模擬電子技術(shù)課程計(jì)報(bào)告題專(zhuān)

目業(yè)

簡(jiǎn)模集萬(wàn)表電工及自化班

級(jí)12電工及自化1）班word檔可自由復(fù)制編輯

課題名指導(dǎo)教（職稱(chēng)）

任務(wù)書(shū)簡(jiǎn)易模集成萬(wàn)用表江春紅執(zhí)行時(shí)

2013~2014學(xué)年

第

學(xué)期

第14

周學(xué)生姓張羽晨徐晶晶何永康

學(xué)號(hào)120914107112091410601209141018

承擔(dān)任設(shè)計(jì)直電壓表并進(jìn)仿真設(shè)計(jì)直電流表并進(jìn)仿真設(shè)計(jì)交電壓表并進(jìn)仿真丁

偉

1209141008

設(shè)計(jì)交電流表并進(jìn)仿真孫學(xué)峰鄧忠建

12091410421209141007

設(shè)計(jì)歐表并進(jìn)行仿整理測(cè)數(shù)據(jù)、整理完成課設(shè)計(jì)報(bào)告設(shè)計(jì)目

1、通過(guò)對(duì)集成萬(wàn)表的的計(jì)了解由成運(yùn)組成的電壓、電等電路，學(xué)在實(shí)際路中應(yīng)用；2、一步熟集成運(yùn)放的性應(yīng)用1、流電壓量范圍0~25V）±5%；2、流電流量范圍0~20mA）±5%3交流電測(cè)量范圍及率范圍有效值0~10V）±5%，50Hz~1000Hz設(shè)計(jì)要4、流電流量范圍及頻范圍：效值（0~20mA）±5%；5、姆表測(cè)（Ω；6、用模擬成電路，器自選。word檔可自由復(fù)制編輯

緒論萬(wàn)用電表簡(jiǎn)稱(chēng)萬(wàn)用表或三用表在國(guó)家標(biāo)準(zhǔn)中稱(chēng)作復(fù)用表萬(wàn)用電表實(shí)際上是一種可以進(jìn)行多種項(xiàng)目測(cè)量的便攜式儀器主要用于測(cè)量電壓電流、電阻另外可粗略判斷電容器、晶體三極管及二極管、集成電路等元器件的性能好壞。在測(cè)量中萬(wàn)用電表的接入因不影響被測(cè)電路原來(lái)的工作狀態(tài)這就要求電壓表應(yīng)具有無(wú)窮大的輸入電阻電流表的內(nèi)阻應(yīng)為零但實(shí)際上萬(wàn)用電表表頭的可動(dòng)線(xiàn)圈總有一定的電阻，例如100uA的表，其內(nèi)阻約為1K，用它進(jìn)行測(cè)量時(shí)將會(huì)影響被測(cè)量，會(huì)引起誤差此外交流電表中整流二極管的壓降和非線(xiàn)性特性也會(huì)產(chǎn)生誤差如果在萬(wàn)用電表中使用運(yùn)算放大器就能大大降低這些誤差提高測(cè)量精度在歐姆表中采用運(yùn)算放大器，不僅能得到線(xiàn)性刻度，還能實(shí)現(xiàn)自動(dòng)調(diào)零。運(yùn)算放大器電路性能的優(yōu)劣直接影響到萬(wàn)用表的性能。本文從運(yùn)算放大器電路的結(jié)構(gòu)、原理出發(fā)，在闡述運(yùn)算放大器電路結(jié)構(gòu)、原理的基礎(chǔ)上用運(yùn)算放大器設(shè)計(jì)電路實(shí)現(xiàn)萬(wàn)用表的電路設(shè)計(jì)。通過(guò)仿真與實(shí)際電路性能指標(biāo)的測(cè)試、分析、比較,總結(jié)出各種電路方案的特點(diǎn),為電路設(shè)計(jì)初學(xué)者提供一定的參考借鑒。word檔可自由復(fù)制編輯

目錄任務(wù)書(shū)·························································································································緒論····························································································································3第一章題目要求與方案論證··························································································51.1簡(jiǎn)模擬集成萬(wàn)用表···························································································1.1.1目要求···································································································1.1.2方論證·································································································1.2課設(shè)計(jì)目的·····································································································第二章電子線(xiàn)路設(shè)計(jì)····································································································62.1萬(wàn)表工作原理·································································································62.1.1直流電壓原理··························································································2.1.2直流電流原理··························································································2.1.3交流電壓原理··························································································2.1.4交流電流原理··························································································2.1.5電阻原理································································································92.2運(yùn)制萬(wàn)用表的電路設(shè)·················································································102.2.1圖：·····································································································102.2.2流電壓的電路圖：···················································································122.2.3流電流的電路圖：···················································································122.2.4流電壓的電路圖：···················································································132.2.5流電流的電路圖：···················································································132.2.6姆表電路圖：·························································································14第三章結(jié)果與分析······································································································153.1用用測(cè)量各種電流、電壓和電·····································································153.1.1直電流的測(cè)量······················································································153.1.2交電流的測(cè)量·······················································································153.1.3流電壓的測(cè)量·························································································163.1.4交電壓的測(cè)量·······················································································173.2測(cè)結(jié)及分析·································································································173.2.1流電壓的測(cè)量結(jié)果及分析：·······································································173.2.2流電流的測(cè)量結(jié)果及分析：·······································································173.2.3流電壓的測(cè)量結(jié)果及分析：·······································································183.2.4流電流的測(cè)量結(jié)果及分析：·······································································183.2.5姆表測(cè)量結(jié)果及分析：·············································································18總結(jié)···························································································································19參考文獻(xiàn)·····················································································································19附錄···························································································································19word檔可自由復(fù)制編輯

第一章

題目要求與案論證1.1易模擬成萬(wàn)用表1.1.1題目要求1、直流電壓測(cè)量范圍0~25V）±5%；2、直流電流測(cè)量范圍）±5%；3、交流電壓測(cè)量范圍及頻率范圍：有效值（）±5%，50Hz~1000Hz4、交流電流測(cè)量范圍及頻率范圍：有效值（）±5%；5、歐姆表測(cè)程0~1KΩ5%；6、采用模擬集成電路，器件自選。1.1.2方案論證在測(cè)量中電表的接入應(yīng)不影響被測(cè)電路的原工作狀態(tài)這就要求電壓表應(yīng)具有無(wú)窮大的輸入電阻流表的內(nèi)阻應(yīng)為零實(shí)際上用表表頭的可動(dòng)線(xiàn)圈總有一定的電阻。例如100μA的表頭，其內(nèi)阻約為1KΩ，用它進(jìn)行測(cè)量時(shí)將影響被測(cè)量量，引起誤差。此外交流電表中的整流二極管和非線(xiàn)性特性也會(huì)產(chǎn)生誤差如果在萬(wàn)用表中使用運(yùn)算放器，就能大大降低這些誤差高測(cè)量精度在歐姆表中采用運(yùn)算放大器不僅能得到線(xiàn)性刻度，還能實(shí)現(xiàn)自動(dòng)調(diào)零。1.2程設(shè)計(jì)的1、通過(guò)對(duì)集成萬(wàn)用表的的設(shè)計(jì)、了解由集成運(yùn)放組成的測(cè)電壓、電流等電路，學(xué)會(huì)在實(shí)際電路中應(yīng)用；2、進(jìn)一步熟悉集成運(yùn)放的線(xiàn)性應(yīng)用。word檔可自由復(fù)制編輯

第二章

電子線(xiàn)路設(shè)2.1用表工原理萬(wàn)用表的基本原理是利用一只靈敏的磁電式直流電流（微安表做表頭當(dāng)微小電流通過(guò)表頭，就會(huì)有電流指示表頭不能通過(guò)大電流，所以，必須在表頭上并聯(lián)與串聯(lián)一些電阻進(jìn)行分流或降壓，從而測(cè)出電路中的電流、電壓和電阻。下面分別介紹。2.1.1測(cè)直流電壓原理圖2-1為同相端輸入高進(jìn)度直流電壓表電原理圖為了減小表頭參數(shù)對(duì)測(cè)量精度的影響，將表頭至于運(yùn)算放大器的反饋回路中，這時(shí)，流經(jīng)表頭的電流與表頭的參數(shù)無(wú)關(guān)，只要改變R1一個(gè)電阻，就可以進(jìn)行量程的切換。圖表頭電流I與被測(cè)電壓Ui的關(guān)系為：I=Ui/R1應(yīng)當(dāng)指出圖1適用于測(cè)量電路與運(yùn)算放大器共地的有關(guān)電路此外當(dāng)被測(cè)電壓較高時(shí)，在運(yùn)放的輸入端應(yīng)設(shè)置衰減器。word檔可自由復(fù)制編輯

2.1.2測(cè)直流電流原理圖2-2是浮地直流電流表的電原理圖電流測(cè)量中地電流的測(cè)量是普遍存在的。例如若被測(cè)電流無(wú)接地點(diǎn)屬于這種情況為此應(yīng)把運(yùn)算放大器的電源也對(duì)地浮動(dòng)。按此種方式構(gòu)成的電流表就可像常規(guī)電流表那樣，串聯(lián)在任何電流通路中測(cè)量電流。圖表頭電流I與被測(cè)電流I1間關(guān)系為：I=(1+R1/R3)I

1可見(jiàn)改變電阻比可調(diào)節(jié)流過(guò)電流表的電流以提高靈敏度該圖被測(cè)電流回路無(wú)接地點(diǎn)，即所謂浮地電流時(shí)，則把運(yùn)算放大器的電源也對(duì)地浮起來(lái)。word檔可自由復(fù)制編輯

2.1.3測(cè)交流電壓原理由運(yùn)算放大器二極管整流橋和直流毫安表組成的交流電壓表如圖2-3所示被測(cè)交流電壓Ui加到運(yùn)算放大器的同相端，故有很高的輸入阻抗，又因?yàn)樨?fù)反饋能減小反饋回路中的非線(xiàn)性影響故把二極管橋路和表頭至于運(yùn)算放大器的反饋回路中減小二極管本身非線(xiàn)性的影響。圖表頭電流I與被測(cè)電壓ui的關(guān)系為：I=Ui/R1word檔可自由復(fù)制編輯

RR2.1.4測(cè)交流電流原理圖4圖2-4為浮地交流電流表頭讀數(shù)由被測(cè)交流電流的全波整流平均值決定，即RI)I22.1.5測(cè)電阻原理圖2-5在此電路中，運(yùn)算放大器改用單電源供電，北側(cè)電阻跨在運(yùn)算放大器的反饋回路中，同相端加基準(zhǔn)電壓U。REFword檔可自由復(fù)制編輯

可見(jiàn)，電流I于被測(cè)電阻成正比，而且表頭具有線(xiàn)性刻度，改變值，可改變歐姆表的量程。這種歐姆表能自動(dòng)調(diào)零Rx=0是電路改成電壓跟隨器U＝U,故表頭電OREF流為零，從而實(shí)現(xiàn)了自動(dòng)調(diào)零。二極管D起保護(hù)作用，如果沒(méi)有D，當(dāng)Rx超量程時(shí)，特別是當(dāng)→∞，運(yùn)算放大器的輸出電壓將接近電源電壓使表頭過(guò)載有了D就可使輸出鉗位，防止表頭過(guò)載。調(diào)整R2，可實(shí)現(xiàn)滿(mǎn)量程調(diào)節(jié)。2.2運(yùn)放制萬(wàn)用表的電設(shè)計(jì)2.2.1總圖：如圖，為設(shè)計(jì)的總電路圖。word檔可自由復(fù)制編輯

電路說(shuō)明黑框以外部位是萬(wàn)用表的內(nèi)部結(jié)構(gòu)黑框以?xún)?nèi)是四種可能的待測(cè)元件四種功能的切換是以開(kāi)關(guān)、S3、的控制完成的，其中在圖示初始狀態(tài)下，開(kāi)關(guān)S1賦予控制鍵A，其余三個(gè)的控制鍵是B，這就能有四種組合方式，從而達(dá)到四種電表的測(cè)量功能。A1010

B0110

電表類(lèi)型直流電流交流電壓直流電壓交流電流其中1示對(duì)應(yīng)鍵在初始態(tài)下按下，0表示初態(tài)。黑框中以類(lèi)似的方式快速切換，便于仿真的進(jìn)行。word檔可自由復(fù)制編輯

2.2.2直流電壓的電路圖：說(shuō)明：5v為測(cè)直流電壓2.2.3直流電流的電路圖：說(shuō)明：為待測(cè)直流電流word檔可自由復(fù)制編輯

2.2.4交流電壓的電路圖：說(shuō)明：5V為測(cè)流電壓有效值2.2.5交流電流的電路圖：說(shuō)明：為待測(cè)交流電流峰值word檔可自由復(fù)制編輯

2.2.6歐姆表電路圖：說(shuō)明：R6為測(cè)電阻，可制程word檔可自由復(fù)制編輯

第三章3.1用萬(wàn)用測(cè)量各種電、電壓電阻對(duì)所設(shè)計(jì)的各個(gè)電表進(jìn)行仿真。3.1.1直流電流的測(cè)量

結(jié)果與分析3.1.2交流電流的測(cè)量word檔可自由復(fù)制編輯

3.1.3直流電壓的測(cè)量word檔可自由復(fù)制編輯

3.1.4交流電壓的測(cè)量3.2測(cè)量結(jié)及分析3.2.1直流電壓的測(cè)量結(jié)果及分析：測(cè)量電壓

絕對(duì)誤差

相對(duì)誤差輸入電壓

10.003V15.003V20.004V

0.040%0.030%0.020%0.020%3.2.2直流電流的測(cè)量結(jié)果及分析：測(cè)量電流

絕對(duì)誤差

相對(duì)誤差5mA

0.0600%輸入電流

10mA15mA

0.0200%0.0067%word檔可自由復(fù)制編輯

3.2.3交流電壓的測(cè)量結(jié)果及分析：輸入電壓

tcos100cos100cos100

測(cè)量電壓1.0400V4.0100V9.0200V

絕對(duì)誤差0.0400V0.0100V0.0200V

相對(duì)誤差4.00%2.50%2.20%3.2.4交流電流的測(cè)量結(jié)果及分析：

測(cè)量電流5.002mA

絕對(duì)誤差0.002mA

相對(duì)誤差0.040%輸入電流

0.003mA

0.030%

0.003mA

0.020%3.2.5歐姆表測(cè)量結(jié)果及分析：輸入電阻

ΩΩΩ

測(cè)量電阻303.5Ω601.8Ω902.2Ω

絕對(duì)誤差3.5Ω1.8Ω2.2Ω

相對(duì)誤差0.44%0.31%0.22%word檔可自由復(fù)制編輯

總結(jié)萬(wàn)用表主要用于測(cè)量電壓電流電阻另外可粗略判斷電容器晶體三極管及二極管、集成電路等元器件的性能好壞文從運(yùn)算放大器電路的結(jié)構(gòu)、原理出發(fā)，在闡述運(yùn)算放大器電路結(jié)構(gòu)、原理的基礎(chǔ)用運(yùn)算放大器設(shè)計(jì)電路實(shí)現(xiàn)萬(wàn)用表的電路設(shè)計(jì)。通過(guò)仿真與實(shí)際電路性能指標(biāo)的測(cè)試、分析、比較,結(jié)出各種電路方案的特點(diǎn),為電路設(shè)計(jì)初學(xué)者提供一定的參考借鑒課題中萬(wàn)用電表的電性能測(cè)試要用標(biāo)準(zhǔn)電壓電流表校正歐姆表用標(biāo)準(zhǔn)電阻校正?？紤]實(shí)驗(yàn)要求不高，建議用數(shù)字式萬(wàn)用電表作為標(biāo)準(zhǔn)表。通過(guò)這次課程設(shè)計(jì)讓我們懂得了理論與實(shí)際操作之間的差距我們體會(huì)到了模電理論知識(shí)的實(shí)用發(fā)現(xiàn)了自身知識(shí)的不足，積累了課程設(shè)計(jì)的經(jīng)驗(yàn)。小組合作共同完成任務(wù)更讓我們學(xué)會(huì)了合理分工與協(xié)調(diào)合作會(huì)到合作的重要性認(rèn)識(shí)到每一個(gè)課題務(wù)都需要小組成員的共同努力與付出課程設(shè)計(jì)從各方面讓我們組全體成員都學(xué)到了很多，十分感謝學(xué)校給我們學(xué)習(xí)的機(jī)會(huì)。由于我們第一次進(jìn)行此類(lèi)課程設(shè)計(jì)在完成課題時(shí)難免有很多紕漏所以在課程設(shè)計(jì)過(guò)程中江老師的多次認(rèn)真輔導(dǎo)和熱心幫助讓我們有很大進(jìn)步使我們受益匪淺最后我們?nèi)M成員對(duì)江老師的辛勤輔導(dǎo)表示由衷的感謝。參考文獻(xiàn)[1]清華大學(xué)電子學(xué)教研組編童詩(shī)白華成英主編.《模擬電子技術(shù)基礎(chǔ)第版北京；高等教育出版社，[2]王艷春主編子技術(shù)實(shí)驗(yàn)與Multisim真》合肥；合肥工業(yè)大學(xué)出版社，[3]衣承斌，劉京南編《模擬集成電子技術(shù)基礎(chǔ)》南京；東南大學(xué)出版社，附錄一、實(shí)驗(yàn)設(shè)備和主要元器件1、運(yùn)算放器HA177412、毫伏表表頭滿(mǎn)偏電