如果(guo)講電(dian)(dian)(dian)阻、電(dian)(dian)(dian)容、電(dian)(dian)(dian)感三(san)大元(yuan)件(jian)(jian)是(shi)我們(men)最常(chang)見的(de)電(dian)(dian)(dian)子(zi)元(yuan)件(jian)(jian)的(de)話(hua),而(er)(er)二極管(guan)(guan)則是(shi)我們(men)見到最多的(de)半(ban)導體(ti)(ti)電(dian)(dian)(dian)子(zi)元(yuan)件(jian)(jian)。為(wei)什么說二極管(guan)(guan)不同于(yu)電(dian)(dian)(dian)阻、電(dian)(dian)(dian)容、電(dian)(dian)(dian)感而(er)(er)被稱(cheng)為(wei)半(ban)導體(ti)(ti)電(dian)(dian)(dian)子(zi)元(yuan)件(jian)(jian)那?這是(shi)因為(wei)二極管(guan)(guan)是(shi)利用半(ban)導體(ti)(ti)材料根據其電(dian)(dian)(dian)荷有P極流向N極的(de)特性而(er)(er)制(zhi)成的(de),故被稱(cheng)為(wei)半(ban)導體(ti)(ti)電(dian)(dian)(dian)子(zi)元(yuan)件(jian)(jian)。比它功能更強大的(de)三(san)極管(guan)(guan)、MOS管(guan)(guan)等元(yuan)件(jian)(jian)也是(shi)半(ban)導體(ti)(ti)電(dian)(dian)(dian)子(zi)元(yuan)件(jian)(jian)。
二(er)極管(guan)(guan)(guan)(guan)(guan)有兩個管(guan)(guan)(guan)(guan)(guan)腳,一(yi)個是(shi)(shi)正(zheng)(zheng)極一(yi)個是(shi)(shi)負極,它最大的(de)特性是(shi)(shi)單向(xiang)(xiang)導電(dian)性,既電(dian)荷(he)只能(neng)由正(zheng)(zheng)極流向(xiang)(xiang)負極。二(er)極管(guan)(guan)(guan)(guan)(guan)主(zhu)要的(de)參數有額定(ding)電(dian)流、額定(ding)電(dian)壓、結電(dian)壓等(deng),選用(yong)時應根據(ju)實際要求(qiu)加以(yi)甄(zhen)別選用(yong)。二(er)極管(guan)(guan)(guan)(guan)(guan)種類很多功能(neng)各異,常見的(de)有整流二(er)極管(guan)(guan)(guan)(guan)(guan),穩壓二(er)極管(guan)(guan)(guan)(guan)(guan),發光二(er)極管(guan)(guan)(guan)(guan)(guan)等(deng)。
整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)是用來(lai)將AC變為DC的(de)(de)(de)(de),在(zai)單相(xiang)整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu)當中(zhong)根據所用二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)的(de)(de)(de)(de)數量(liang)分為:采(cai)用單只二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)的(de)(de)(de)(de)半(ban)波整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu);利用變壓(ya)器(qi)抽(chou)頭加兩只二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)的(de)(de)(de)(de)全(quan)波整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu);以及(ji)利用四只二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)構成的(de)(de)(de)(de)橋式整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu)。三相(xiang)整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu)分為半(ban)波整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu)和三相(xiang)全(quan)橋式整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu)。這些電(dian)(dian)路(lu)(lu)的(de)(de)(de)(de)相(xiang)關(guan)知識在(zai)一般(ban)電(dian)(dian)子(zi)技術教材(cai)當中(zhong)均有(you)講解,詳情(qing)請(qing)參考相(xiang)關(guan)資料(liao)。我們在(zai)工(gong)作當中(zhong)常見整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)應用的(de)(de)(de)(de)地方有(you)各種電(dian)(dian)子(zi)設備初級整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)側,真空交流(liu)(liu)(liu)(liu)接觸器(qi)吸(xi)合線圈(quan)(quan)前面(mian)的(de)(de)(de)(de)整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)路(lu)(lu)等(deng)。我們常見的(de)(de)(de)(de)整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)多為黑色(se)塑封的(de)(de)(de)(de)1.5A的(de)(de)(de)(de)1N4700--1N4707系(xi)列。整(zheng)(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)(liu)二(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)(guan)一般(ban)在(zai)其表面(mian)用一圈(quan)(quan)銀環來(lai)指示負(fu)極(ji)(ji)(ji)所在(zai)。
穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)常用(yong)(yong)(yong)在(zai)對(dui)直流(liu)電(dian)壓(ya)值(zhi)有一定(ding)要(yao)求的(de)電(dian)路(lu)當中。穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)是利(li)用(yong)(yong)(yong)二(er)(er)極(ji)(ji)(ji)管(guan)反向(xiang)(xiang)擊穿特性(xing)(xing)而制(zhi)作的(de)元件,其在(zai)電(dian)路(lu)當中最應該注(zhu)意的(de)一點既(ji)穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)要(yao)反向(xiang)(xiang)使用(yong)(yong)(yong),也(ye)就是要(yao)將穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)的(de)負(fu)極(ji)(ji)(ji)接電(dian)源的(de)正(zheng)極(ji)(ji)(ji),其正(zheng)極(ji)(ji)(ji)接電(dian)源的(de)負(fu)極(ji)(ji)(ji),這一點要(yao)牢記。常用(yong)(yong)(yong)的(de)穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)有1N4728--1N4769系列,其穩(wen)壓(ya)范(fan)圍3.3v--100v。但由(you)于穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)的(de)輸出電(dian)流(liu)值(zhi)不大,故常用(yong)(yong)(yong)在(zai)工(gong)作電(dian)流(liu)較小的(de)線路(lu)當中。此(ci)外利(li)用(yong)(yong)(yong)穩(wen)壓(ya)二(er)(er)極(ji)(ji)(ji)管(guan)的(de)穩(wen)壓(ya)特性(xing)(xing)在(zai)有關電(dian)子線路(lu)當中,它還(huan)被賦予限幅(fu)、電(dian)壓(ya)采用(yong)(yong)(yong)比較的(de)作用(yong)(yong)(yong)。
發(fa)光(guang)(guang)二極(ji)管(guan)(guan)是我們在工(gong)作(zuo)指示(shi)和日常照(zhao)明當(dang)中(zhong)常接觸(chu)到的(de)(de)元(yuan)件,我們一般(ban)(ban)采用其英文縮寫LED來代(dai)指它。由(you)于現(xian)在大功率(lv)發(fa)光(guang)(guang)二極(ji)管(guan)(guan)的(de)(de)不斷涌現(xian),原有普亮、超(chao)亮、甚亮的(de)(de)分(fen)類方法已很難適用。發(fa)光(guang)(guang)二極(ji)管(guan)(guan)的(de)(de)工(gong)作(zuo)電壓(ya)一般(ban)(ban)為2.5--4.5v左(zuo)右(you),在高于其工(gong)作(zuo)電壓(ya)的(de)(de)電路中(zhong)要串入合適的(de)(de)降(jiang)壓(ya)電阻才能保障發(fa)光(guang)(guang)二極(ji)管(guan)(guan)的(de)(de)正常工(gong)作(zuo)。發(fa)光(guang)(guang)二級管(guan)(guan)同(tong)樣是有極(ji)性(xing)的(de)(de)元(yuan)件,一般(ban)(ban)帽式發(fa)光(guang)(guang)二極(ji)管(guan)(guan)管(guan)(guan)腳較長的(de)(de)一端為正極(ji),大功率(lv)片狀發(fa)光(guang)(guang)二極(ji)管(guan)(guan)一般(ban)(ban)都會(hui)在元(yuan)件焊接處給予極(ji)性(xing)符號標示(shi)的(de)(de),使(shi)用或更換時要注(zhu)意。
此外二(er)極(ji)(ji)管(guan)(guan)(guan)家族當中(zhong)還有檢波二(er)極(ji)(ji)管(guan)(guan)(guan)、開(kai)關二(er)極(ji)(ji)管(guan)(guan)(guan)、激光(guang)二(er)極(ji)(ji)管(guan)(guan)(guan)、變容二(er)極(ji)(ji)管(guan)(guan)(guan)等許多種類的二(er)極(ji)(ji)管(guan)(guan)(guan)。大家在使(shi)用和檢修時應仔(zi)細閱讀其參(can)數說明書。總之,認(ren)識和掌(zhang)握二(er)極(ji)(ji)管(guan)(guan)(guan)這種最基(ji)礎(chu)的半導體元(yuan)件,是(shi)我們學習電(dian)子知識的必經之路。
