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PCB板(ban)根據電路(lu)層數(shu)分(fen)類(lei)：分(fen)為單(dan)面(mian)板(ban)、雙面(mian)板(ban)和(he)(he)多層板(ban)，下面(mian)簡單(dan)介紹三種主(zhu)要類(lei)型和(he)(he)特點：

　　單面板

　　單(dan)(dan)面(mian)(mian)板(ban)(ban)(Single-Sided Boards) 在(zai)(zai)(zai)最基本(ben)的PCB上，零件(jian)集中(zhong)在(zai)(zai)(zai)其(qi)中(zhong)一面(mian)(mian)，導線(xian)則集中(zhong)在(zai)(zai)(zai)另一面(mian)(mian)上(有(you)(you)貼片元件(jian)時和導線(xian)為同(tong)一面(mian)(mian)，插件(jian)器(qi)件(jian)再(zai)另一面(mian)(mian))。因為導線(xian)只出現在(zai)(zai)(zai)其(qi)中(zhong)一面(mian)(mian)，所以這種(zhong)PCB叫(jiao)作單(dan)(dan)面(mian)(mian)板(ban)(ban)(Single-sided)。因為單(dan)(dan)面(mian)(mian)板(ban)(ban)在(zai)(zai)(zai)設計線(xian)路上有(you)(you)許多嚴(yan)格的限制(因為只有(you)(you)一面(mian)(mian)，布線(xian)間(jian)不(bu)能交叉而必須繞獨自的路徑)，所以只有(you)(you)早(zao)期的電路才使用(yong)這類的板(ban)(ban)子(zi)。

　　雙面板

　　雙(shuang)面(mian)板(ban)(ban)(Double-Sided Boards) 這種電路板(ban)(ban)的(de)(de)兩(liang)面(mian)都(dou)有(you)布(bu)線(xian)，不過(guo)要用(yong)上(shang)(shang)兩(liang)面(mian)的(de)(de)導(dao)(dao)(dao)線(xian)，必須(xu)要在(zai)(zai)兩(liang)面(mian)間有(you)適當的(de)(de)電路連接(jie)才(cai)行。這種電路間的(de)(de)“橋梁”叫做導(dao)(dao)(dao)孔(kong)(kong)(via)。導(dao)(dao)(dao)孔(kong)(kong)是(shi)在(zai)(zai)PCB上(shang)(shang)，充(chong)滿或涂上(shang)(shang)金屬的(de)(de)小洞，它(ta)可以與兩(liang)面(mian)的(de)(de)導(dao)(dao)(dao)線(xian)相連接(jie)。因為雙(shuang)面(mian)板(ban)(ban)的(de)(de)面(mian)積(ji)比(bi)單(dan)(dan)面(mian)板(ban)(ban)大了一倍，雙(shuang)面(mian)板(ban)(ban)解決了單(dan)(dan)面(mian)板(ban)(ban)中因為布(bu)線(xian)交錯的(de)(de)難(nan)點(dian)(可以通過(guo)孔(kong)(kong)導(dao)(dao)(dao)通到另(ling)一面(mian))，它(ta)更適合用(yong)在(zai)(zai)比(bi)單(dan)(dan)面(mian)板(ban)(ban)更復雜的(de)(de)電路上(shang)(shang)。

　　多層板

　　多(duo)層(ceng)(ceng)板(ban)(ban)(ban)(ban)(ban)(Multi-Layer Boards) 為了增加可以布線的(de)面(mian)積，多(duo)層(ceng)(ceng)板(ban)(ban)(ban)(ban)(ban)用(yong)上(shang)了更多(duo)單(dan)或雙面(mian)的(de)布線板(ban)(ban)(ban)(ban)(ban)。用(yong)一(yi)塊雙面(mian)作內(nei)層(ceng)(ceng)、二(er)塊單(dan)面(mian)作外層(ceng)(ceng)或二(er)塊雙面(mian)作內(nei)層(ceng)(ceng)、二(er)塊單(dan)面(mian)作外層(ceng)(ceng)的(de)印刷線路(lu)板(ban)(ban)(ban)(ban)(ban)，通過(guo)(guo)定位系(xi)統及(ji)絕緣粘結(jie)材料交替(ti)在(zai)一(yi)起且(qie)(qie)導電(dian)圖形按設計(ji)要求進行互連的(de)印刷線路(lu)板(ban)(ban)(ban)(ban)(ban)就(jiu)成(cheng)為四層(ceng)(ceng)、六(liu)層(ceng)(ceng)印刷電(dian)路(lu)板(ban)(ban)(ban)(ban)(ban)了，也稱為多(duo)層(ceng)(ceng)印刷線路(lu)板(ban)(ban)(ban)(ban)(ban)。板(ban)(ban)(ban)(ban)(ban)子的(de)層(ceng)(ceng)數并不代表(biao)有幾(ji)層(ceng)(ceng)獨(du)立(li)的(de)布線層(ceng)(ceng)，在(zai)特殊(shu)情況(kuang)下會加入空(kong)層(ceng)(ceng)來(lai)控(kong)制(zhi)板(ban)(ban)(ban)(ban)(ban)厚(hou)，通常層(ceng)(ceng)數都是偶數，并且(qie)(qie)包含最外側的(de)兩層(ceng)(ceng)。大(da)(da)部分的(de)主機板(ban)(ban)(ban)(ban)(ban)都是4到(dao)8層(ceng)(ceng)的(de)結(jie)構(gou)，不過(guo)(guo)技術上(shang)理論可以做(zuo)到(dao)近100層(ceng)(ceng)的(de)PCB板(ban)(ban)(ban)(ban)(ban)。大(da)(da)型的(de)超級計(ji)算(suan)機大(da)(da)多(duo)使(shi)用(yong)相當多(duo)層(ceng)(ceng)的(de)主機板(ban)(ban)(ban)(ban)(ban)，不過(guo)(guo)因(yin)(yin)為這類計(ji)算(suan)機已經(jing)可以用(yong)許多(duo)普通計(ji)算(suan)機的(de)集群(qun)代替(ti)，超多(duo)層(ceng)(ceng)板(ban)(ban)(ban)(ban)(ban)已經(jing)漸漸不被使(shi)用(yong)了。因(yin)(yin)為PCB中的(de)各層(ceng)(ceng)都緊密的(de)結(jie)合，一(yi)般不太容易看(kan)(kan)出(chu)實(shi)際數目，不過(guo)(guo)如果仔細觀(guan)察主機板(ban)(ban)(ban)(ban)(ban)，還(huan)是可以看(kan)(kan)出(chu)來(lai)。