如果講電(dian)阻、電(dian)容、電(dian)感三(san)(san)大(da)元件是(shi)(shi)我們最(zui)常見的電(dian)子(zi)元件的話,而二極(ji)管(guan)則(ze)是(shi)(shi)我們見到最(zui)多的半導(dao)(dao)體電(dian)子(zi)元件。為(wei)(wei)什么說(shuo)二極(ji)管(guan)不同(tong)于電(dian)阻、電(dian)容、電(dian)感而被稱(cheng)為(wei)(wei)半導(dao)(dao)體電(dian)子(zi)元件那?這是(shi)(shi)因為(wei)(wei)二極(ji)管(guan)是(shi)(shi)利用半導(dao)(dao)體材料根據其(qi)電(dian)荷(he)有(you)P極(ji)流向(xiang)N極(ji)的特性而制(zhi)成的,故被稱(cheng)為(wei)(wei)半導(dao)(dao)體電(dian)子(zi)元件。比它功能更(geng)強大(da)的三(san)(san)極(ji)管(guan)、MOS管(guan)等元件也是(shi)(shi)半導(dao)(dao)體電(dian)子(zi)元件。
二(er)(er)極管(guan)有(you)兩個(ge)管(guan)腳,一個(ge)是正(zheng)極一個(ge)是負(fu)極,它(ta)最大的特(te)性是單向導電(dian)(dian)性,既(ji)電(dian)(dian)荷(he)只能由(you)正(zheng)極流(liu)(liu)(liu)向負(fu)極。二(er)(er)極管(guan)主要的參數有(you)額定(ding)電(dian)(dian)流(liu)(liu)(liu)、額定(ding)電(dian)(dian)壓(ya)、結電(dian)(dian)壓(ya)等(deng),選用(yong)(yong)時應根據實際要求(qiu)加(jia)以甄別選用(yong)(yong)。二(er)(er)極管(guan)種類(lei)很(hen)多功能各異,常(chang)見(jian)的有(you)整流(liu)(liu)(liu)二(er)(er)極管(guan),穩壓(ya)二(er)(er)極管(guan),發光二(er)(er)極管(guan)等(deng)。
整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)二(er)(er)極(ji)管(guan)(guan)是用(yong)(yong)(yong)來將(jiang)AC變為(wei)DC的(de)(de)(de)(de),在(zai)單相(xiang)整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu)當中(zhong)(zhong)根據所用(yong)(yong)(yong)二(er)(er)極(ji)管(guan)(guan)的(de)(de)(de)(de)數量分為(wei):采用(yong)(yong)(yong)單只二(er)(er)極(ji)管(guan)(guan)的(de)(de)(de)(de)半波整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu);利(li)用(yong)(yong)(yong)變壓器(qi)抽頭加兩只二(er)(er)極(ji)管(guan)(guan)的(de)(de)(de)(de)全波整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu);以及(ji)利(li)用(yong)(yong)(yong)四只二(er)(er)極(ji)管(guan)(guan)構(gou)成的(de)(de)(de)(de)橋式整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu)。三相(xiang)整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu)分為(wei)半波整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu)和三相(xiang)全橋式整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu)。這些電(dian)路(lu)的(de)(de)(de)(de)相(xiang)關知識在(zai)一般電(dian)子技術教材(cai)當中(zhong)(zhong)均有(you)講(jiang)解,詳情請參(can)考相(xiang)關資料。我們在(zai)工(gong)作(zuo)當中(zhong)(zhong)常見整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)二(er)(er)極(ji)管(guan)(guan)應用(yong)(yong)(yong)的(de)(de)(de)(de)地方(fang)有(you)各種電(dian)子設(she)備初級整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)側,真(zhen)空交(jiao)流(liu)(liu)(liu)接觸器(qi)吸合線圈前(qian)面的(de)(de)(de)(de)整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)路(lu)等。我們常見的(de)(de)(de)(de)整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)二(er)(er)極(ji)管(guan)(guan)多為(wei)黑色塑封(feng)的(de)(de)(de)(de)1.5A的(de)(de)(de)(de)1N4700--1N4707系列。整(zheng)(zheng)(zheng)(zheng)流(liu)(liu)(liu)二(er)(er)極(ji)管(guan)(guan)一般在(zai)其(qi)表面用(yong)(yong)(yong)一圈銀環來指(zhi)示負極(ji)所在(zai)。
穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管常用(yong)(yong)(yong)(yong)(yong)在(zai)對直流電壓(ya)(ya)(ya)值有(you)一定(ding)要(yao)(yao)求(qiu)的(de)電路當中(zhong)。穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管是(shi)利用(yong)(yong)(yong)(yong)(yong)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管反(fan)(fan)向擊穿特性而制作的(de)元件,其(qi)在(zai)電路當中(zhong)最應該注意(yi)的(de)一點既穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管要(yao)(yao)反(fan)(fan)向使用(yong)(yong)(yong)(yong)(yong),也就(jiu)是(shi)要(yao)(yao)將穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管的(de)負極(ji)(ji)(ji)(ji)(ji)接電源的(de)正極(ji)(ji)(ji)(ji)(ji),其(qi)正極(ji)(ji)(ji)(ji)(ji)接電源的(de)負極(ji)(ji)(ji)(ji)(ji),這一點要(yao)(yao)牢記。常用(yong)(yong)(yong)(yong)(yong)的(de)穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管有(you)1N4728--1N4769系列(lie),其(qi)穩(wen)(wen)壓(ya)(ya)(ya)范圍3.3v--100v。但由于穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管的(de)輸出電流值不大,故常用(yong)(yong)(yong)(yong)(yong)在(zai)工作電流較小的(de)線(xian)路當中(zhong)。此外利用(yong)(yong)(yong)(yong)(yong)穩(wen)(wen)壓(ya)(ya)(ya)二(er)(er)極(ji)(ji)(ji)(ji)(ji)管的(de)穩(wen)(wen)壓(ya)(ya)(ya)特性在(zai)有(you)關電子線(xian)路當中(zhong),它(ta)還被賦予限(xian)幅(fu)、電壓(ya)(ya)(ya)采用(yong)(yong)(yong)(yong)(yong)比較的(de)作用(yong)(yong)(yong)(yong)(yong)。
發(fa)光二(er)(er)極管(guan)是(shi)我們在工作(zuo)指示和日常照明當中常接(jie)(jie)觸到的(de)(de)元(yuan)件,我們一(yi)般(ban)(ban)采用其英文(wen)縮寫(xie)LED來代(dai)指它。由于(yu)現在大功(gong)(gong)率(lv)發(fa)光二(er)(er)極管(guan)的(de)(de)不斷(duan)涌現,原有普(pu)亮、超亮、甚(shen)亮的(de)(de)分類(lei)方法已很難(nan)適(shi)用。發(fa)光二(er)(er)極管(guan)的(de)(de)工作(zuo)電(dian)(dian)壓一(yi)般(ban)(ban)為2.5--4.5v左右,在高于(yu)其工作(zuo)電(dian)(dian)壓的(de)(de)電(dian)(dian)路中要串(chuan)入合適(shi)的(de)(de)降壓電(dian)(dian)阻(zu)才能保(bao)障發(fa)光二(er)(er)極管(guan)的(de)(de)正常工作(zuo)。發(fa)光二(er)(er)級管(guan)同(tong)樣(yang)是(shi)有極性的(de)(de)元(yuan)件,一(yi)般(ban)(ban)帽式發(fa)光二(er)(er)極管(guan)管(guan)腳(jiao)較長(chang)的(de)(de)一(yi)端為正極,大功(gong)(gong)率(lv)片狀發(fa)光二(er)(er)極管(guan)一(yi)般(ban)(ban)都會在元(yuan)件焊接(jie)(jie)處(chu)給予極性符號(hao)標示的(de)(de),使(shi)用或更換時要注意。
此(ci)外二極(ji)(ji)管(guan)(guan)(guan)(guan)家族當中還有檢波二極(ji)(ji)管(guan)(guan)(guan)(guan)、開關二極(ji)(ji)管(guan)(guan)(guan)(guan)、激光二極(ji)(ji)管(guan)(guan)(guan)(guan)、變容二極(ji)(ji)管(guan)(guan)(guan)(guan)等許多(duo)種(zhong)類的(de)二極(ji)(ji)管(guan)(guan)(guan)(guan)。大家在(zai)使用和檢修時應仔細閱(yue)讀其參(can)數(shu)說明書。總之,認識和掌握(wo)二極(ji)(ji)管(guan)(guan)(guan)(guan)這種(zhong)最基礎的(de)半(ban)導體元(yuan)件,是(shi)我(wo)們學習電子知識的(de)必經之路。
