電子元件(jian)是組成電子產品的基(ji)礎，了解常用的電子(zi)元件的種類、結構、性(xing)能并(bing)能正(zheng)確(que)選用是學習(xi)、掌握電子技術(shu)的基本。常(chang)用的電子元件有(you)：電阻、電容、電感、電位器、變壓(ya)器等，就安裝方式(shi)而(er)言，目(mu)前可分為傳統安裝（又稱通孔裝即DIP）和表面安裝兩(liang)大類(lei)（即又稱SMT或SMD）。三極管、二極管稱為電子器件。

單面板：電路板只有一面用金屬處理；雙面板：電路板雙面(mian)都用金屬處理；

元件面：電路板上插元件的一面；焊接面：元件面的反面，存在(zai)許(xu)多焊盤以(yi)供焊接(jie)；

焊盤：PCB板上用于焊接元(yuan)件引腳或金屬端的金屬部分(fen)；層板：除電路板雙面外，電路板內層也有線路；

空焊：零件腳或引線腳與錫墊間由于某種原因沒有完成接合；假焊：類似于空焊，由于零件腳或引線腳與錫墊間(jian)焊(han)錫量太少，沒有達到接合標準；

冷焊：錫或錫膏在回風爐氣化后，在錫(xi)墊上仍(reng)有(you)模糊的粒(li)狀附著物(wu)；橋接：零件腳與腳之間焊錫聯接短路；

金屬化孔：用于插元件或布明線的金屬化孔；連接孔：與金屬化孔相對，不用于插元件或布明線的金屬(shu)化孔；

極性元件：需定向插入電路板的元件；跪腳：零件腳(jiao)打(da)折形成跪(gui)腳；錯件：零件放置的規格或種類與要求不符；

缺件：應放置零件的位置產生空缺；自檢：由工作的完成者依據規定的規則對(dui)該工(gong)作進(jin)行的檢驗；

電子元件：指在工廠生產加工時不改變分子成分的成品。如電阻器、電容器、電感器。因為它本身不產生電(dian)(dian)子(zi)，它對電(dian)(dian)壓、電(dian)(dian)流無(wu)(wu)控制和變(bian)換作(zuo)用，所(suo)以又稱無(wu)(wu)源器件。按(an)分(fen)類標準，電(dian)(dian)子(zi)元件可分(fen)為11個大類(lei)。

電子器件：指在工廠生產加工時改變了分子結構的成品。例如晶體管、電子管、集成電路。因為它本身能產生電子，對電壓、電流有控制、變換作用（放大、開關、整流、檢波、振蕩和調制等），所以又稱有源器(qi)件。按(an)分(fen)類標準(zhun)，電子(zi)器(qi)件可分為12個大類，可歸納為真空電子器件和半導體器件兩大塊。【詳細>>】

電阻器在電路中起什么作用呢？

將電(dian)路中的(de)(de)(de)開關換(huan)為1個470歐姆的(de)(de)(de)電(dian)位器(qi)。旋轉(zhuan)電(dian)位器(qi)的(de)(de)(de)轉(zhuan)柄，小(xiao)燈(deng)泡的(de)(de)(de)亮度要隨著電(dian)阻值(zhi)的(de)(de)(de)大(da)小(xiao)而改變(bian)。電(dian)阻值(zhi)越大(da)，小(xiao)燈(deng)泡越暗。這說(shuo)明(ming)電(dian)阻器(qi)在電(dian)路中可以控制電(dian)流的(de)(de)(de)強(qiang)弱。

電容器在電路中有什么作用呢？

用電(dian)(dian)(dian)(dian)(dian)(dian)容器代替開關。接通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)(dian)路時(shi)，我們(men)看到小(xiao)燈(deng)泡閃亮(liang)一下后就不(bu)再(zai)亮(liang)了。這(zhe)是因為(wei)電(dian)(dian)(dian)(dian)(dian)(dian)容器在充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的瞬(shun)間，電(dian)(dian)(dian)(dian)(dian)(dian)路中有電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)。而充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過(guo)程很快結束了，電(dian)(dian)(dian)(dian)(dian)(dian)容器充(chong)滿電(dian)(dian)(dian)(dian)(dian)(dian)荷(he)后，電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)消失了。電(dian)(dian)(dian)(dian)(dian)(dian)容器容量越小(xiao)，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)所用時(shi)間越短暫(zan)，可(ke)見直(zhi)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)是不(bu)能(neng)通(tong)(tong)(tong)過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)容器的。若將電(dian)(dian)(dian)(dian)(dian)(dian)源改(gai)為(wei)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)源，小(xiao)燈(deng)泡將持(chi)續發(fa)光，若交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)頻(pin)率(lv)可(ke)以(yi)變化，那么(me)在相同的電(dian)(dian)(dian)(dian)(dian)(dian)壓下，高頻(pin)率(lv)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)較低(di)頻(pin)率(lv)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)更(geng)(geng)易于(yu)通(tong)(tong)(tong)過(guo)同一個電(dian)(dian)(dian)(dian)(dian)(dian)容器而使小(xiao)燈(deng)泡更(geng)(geng)亮(liang)些(xie)。這(zhe)些(xie)實驗可(ke)以(yi)說明(ming)電(dian)(dian)(dian)(dian)(dian)(dian)容器在電(dian)(dian)(dian)(dian)(dian)(dian)路中，可(ke)以(yi)起“隔直(zhi)流(liu)(liu)，通(tong)(tong)(tong)交(jiao)(jiao)流(liu)(liu)”，“通(tong)(tong)(tong)高頻(pin)、阻低(di)頻(pin)”的作用。

晶體二極管在電路中有什么作用呢？

我們將(jiang)晶體二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)接(jie)在電(dian)(dian)(dian)(dian)路中(zhong)(zhong)的開關位置上(shang)，燈泡發光，說明(ming)這(zhe)時二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)導通，二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)的電(dian)(dian)(dian)(dian)阻（稱為正向電(dian)(dian)(dian)(dian)阻）很(hen)小。若將(jiang)二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)兩極(ji)(ji)(ji)引腳對調，這(zhe)時小燈泡不(bu)亮了。這(zhe)時二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)的電(dian)(dian)(dian)(dian)阻（稱為反向電(dian)(dian)(dian)(dian)阻）很(hen)大，電(dian)(dian)(dian)(dian)路中(zhong)(zhong)幾乎(hu)沒有電(dian)(dian)(dian)(dian)流(liu)。這(zhe)個(ge)現象說明(ming)二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)有單向導電(dian)(dian)(dian)(dian)的特(te)性。利用(yong)二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)的這(zhe)個(ge)特(te)性，可(ke)使用(yong)二(er)(er)(er)(er)極(ji)(ji)(ji)管(guan)(guan)進行檢波和整流(liu)。

1、通(tong)過電(dian)子(zi)元器件(jian)網(wang)絡平(ping)臺找有工商(shang)注冊的正規(gui)公(gong)司；

2、了解供應商資質，三證是否齊全(quan),業務員的素質及服(fu)務；

3、電(dian)子元器(qi)件的型號細節部分，如產品的誤差、材質、封裝(zhuang)、腳距(ju)、后綴字(zi)母，細微環節要注(zhu)意，避免出現(xian)產品不符退換貨，耽(dan)誤(wu)工程生產(chan)進(jin)度；

4、大型(xing)工(gong)廠注(zhu)重高(gao)端質量，中(zhong)小(xiao)型工(gong)廠偏向成本和中高端質量(liang)；

5、在控制(zhi)成(cheng)本的問題上需要特別注意，切勿貪圖小便宜，正視便宜(yi)沒有好貨，可以選擇小批量采樣(yang)，初步確認供應商的產品質量后再進行批量采購。【詳細>>】