隨著世界電(dian)子信息產業的快速發展(zhan)(zhan),作(zuo)為電(dian)子信息(xi)產業(ye)基(ji)礎(chu)的電(dian)子元件產業(ye)發展(zhan)(zhan)也異常迅速。在電(dian)子制作中,要使用到許多不(bu)同(tong)的電(dian)子元件,而電(dian)子元件(jian)正進(jin)入以新型電(dian)子元件(jian)為(wei)主體(ti)的新一代(dai)元器件(jian)時代(dai)。想從事或(huo)了解電子(zi)(zi)信息(xi)產業的人(ren),必須弄明白電子(zi)(zi)元(yuan)件(jian)是什么,電子(zi)(zi)元(yuan)件(jian)和電子(zi)(zi)器件(jian)的區別等(deng)關(guan)于電子(zi)(zi)元(yuan)件(jian)的基礎知(zhi)識。
電(dian)子元件是(shi)組成(cheng)電(dian)子產品(pin)的基(ji)礎,了解常用的電子元件的種類、結構、性能(neng)并能(neng)正確選用是學(xue)習、掌握(wo)電(dian)(dian)子(zi)(zi)技術的(de)基本。常(chang)用的(de)電(dian)(dian)子(zi)(zi)元件有:電(dian)(dian)阻、電(dian)(dian)容、電(dian)(dian)感、電位(wei)器、變(bian)壓器等,就安裝方式而言,目前可分為傳統安裝(又(you)稱通孔(kong)裝即DIP)和表面安裝兩大(da)類(即又稱SMT或SMD)。三極管、二(er)極管稱(cheng)為電子器件(jian)。
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(jin)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,存在許多焊盤以(yi)供焊接(jie);
焊盤:PCB板上用于焊(han)接元件引腳或金屬端的金屬部分;層板:除電路板雙面外,電路板內層也有線路(lu);
空焊:零件腳或引線腳與錫墊間由于某種原因沒有完成接(jie)合;假焊:類似于空焊,由于零件腳或引線腳與(yu)錫墊間焊錫量太少(shao),沒有達到接合標(biao)準;
冷焊:錫或錫膏在回風爐氣化后,在錫墊上仍有模糊的粒狀附著物;橋接:零件腳與腳之間焊錫聯接短(duan)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化孔;
極性元件:需定向插入電路板的元件;跪腳:零件腳打折(zhe)形成跪腳;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(que);自檢:由工作的完成者依據規定的規則對該工作進行的檢驗(yan);
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子,它對電壓、電流(liu)無(wu)控制(zhi)和變換(huan)作用,所以又稱(cheng)無(wu)源器件(jian)。按分類標準,電子元件(jian)可(ke)分為11個大類。
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(yuan)器件。按分類標(biao)準,電子器件可分為(wei)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)(dian)路(lu)中的(de)(de)(de)開關換為1個470歐姆(mu)的(de)(de)(de)電(dian)(dian)位器。旋轉電(dian)(dian)位器的(de)(de)(de)轉柄,小(xiao)燈泡的(de)(de)(de)亮度要(yao)隨著電(dian)(dian)阻(zu)(zu)值(zhi)的(de)(de)(de)大小(xiao)而改變。電(dian)(dian)阻(zu)(zu)值(zhi)越大,小(xiao)燈泡越暗(an)。這(zhe)說明電(dian)(dian)阻(zu)(zu)器在(zai)電(dian)(dian)路(lu)中可以控制電(dian)(dian)流的(de)(de)(de)強弱。
電容器在電路中有什么作用呢?
用電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)代替開關(guan)。接通(tong)電(dian)(dian)(dian)(dian)(dian)(dian)路時,我們看到小燈泡(pao)(pao)閃亮(liang)(liang)一下(xia)(xia)后就(jiu)不(bu)再亮(liang)(liang)了(le)。這是因為電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)在(zai)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)瞬間,電(dian)(dian)(dian)(dian)(dian)(dian)路中(zhong)有電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)。而充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過程很快結(jie)束了(le),電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)充(chong)滿電(dian)(dian)(dian)(dian)(dian)(dian)荷后,電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)消失了(le)。電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)容(rong)量(liang)越(yue)小,充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)所用時間越(yue)短暫,可見直(zhi)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)是不(bu)能通(tong)過電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)的(de)。若將電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)改為交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan),小燈泡(pao)(pao)將持續(xu)發光(guang),若交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)頻(pin)(pin)率(lv)(lv)可以(yi)變化,那么在(zai)相同的(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓下(xia)(xia),高頻(pin)(pin)率(lv)(lv)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)較(jiao)低頻(pin)(pin)率(lv)(lv)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)更(geng)易于通(tong)過同一個電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)而使小燈泡(pao)(pao)更(geng)亮(liang)(liang)些。這些實驗可以(yi)說明電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)器(qi)(qi)在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)路中(zhong),可以(yi)起“隔(ge)直(zhi)流(liu)(liu),通(tong)交(jiao)(jiao)流(liu)(liu)”,“通(tong)高頻(pin)(pin)、阻低頻(pin)(pin)”的(de)作用。
晶體二極管在電路中有什么作用呢?
我們將晶(jing)體二(er)(er)極管(guan)接在電(dian)路中(zhong)的(de)(de)(de)開(kai)關位置上,燈泡發光,說明這(zhe)(zhe)時二(er)(er)極管(guan)導通(tong),二(er)(er)極管(guan)的(de)(de)(de)電(dian)阻(zu)(稱為正向電(dian)阻(zu))很小(xiao)。若將二(er)(er)極管(guan)兩極引腳對調,這(zhe)(zhe)時小(xiao)燈泡不亮了(le)。這(zhe)(zhe)時二(er)(er)極管(guan)的(de)(de)(de)電(dian)阻(zu)(稱為反向電(dian)阻(zu))很大,電(dian)路中(zhong)幾乎沒(mei)有(you)電(dian)流。這(zhe)(zhe)個現(xian)象說明二(er)(er)極管(guan)有(you)單向導電(dian)的(de)(de)(de)特(te)性(xing)。利用(yong)二(er)(er)極管(guan)的(de)(de)(de)這(zhe)(zhe)個特(te)性(xing),可(ke)使用(yong)二(er)(er)極管(guan)進行檢(jian)波和整流。
1、通過(guo)電(dian)子元(yuan)器件(jian)網絡平臺找有工商注冊的正規公(gong)司;
2、了解供應商資(zi)質,三(san)證是否齊全,業(ye)務員的素質及服務;
3、電子(zi)元(yuan)器件的(de)型號細節部分(fen),如產品的(de)誤差(cha)、材質、封裝、腳距(ju)、后綴字母(mu),細微環(huan)節要注意,避(bi)免出現產品(pin)不符退換貨(huo),耽誤工程生產進度;
4、大型工廠注重高端質(zhi)量,中小型工廠偏向成本和中(zhong)高端質量;
5、在控制成本的問題上需(xu)要(yao)特別(bie)注(zhu)意,切勿貪圖(tu)小便宜,正視便宜(yi)沒有好(hao)貨,可(ke)以選(xuan)擇小批量采樣,初步確認供應商的(de)產品質量(liang)后(hou)再進行批量(liang)采(cai)購。【詳細>>】