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PCB板根據電路層數分(fen)類：分(fen)為單面(mian)板、雙面(mian)板和(he)多層板，下面(mian)簡單介紹三種(zhong)主(zhu)要類型和(he)特點：

　　單面板

　　單面(mian)(mian)(mian)板(Single-Sided Boards) 在(zai)(zai)最基(ji)本的(de)PCB上(shang)，零件(jian)(jian)集中(zhong)(zhong)在(zai)(zai)其(qi)(qi)中(zhong)(zhong)一面(mian)(mian)(mian)，導線(xian)(xian)則(ze)集中(zhong)(zhong)在(zai)(zai)另(ling)一面(mian)(mian)(mian)上(shang)(有貼片(pian)元件(jian)(jian)時和導線(xian)(xian)為同一面(mian)(mian)(mian)，插件(jian)(jian)器件(jian)(jian)再另(ling)一面(mian)(mian)(mian))。因為導線(xian)(xian)只(zhi)(zhi)出(chu)現在(zai)(zai)其(qi)(qi)中(zhong)(zhong)一面(mian)(mian)(mian)，所(suo)(suo)以這(zhe)(zhe)種(zhong)PCB叫作單面(mian)(mian)(mian)板(Single-sided)。因為單面(mian)(mian)(mian)板在(zai)(zai)設(she)計(ji)線(xian)(xian)路上(shang)有許多嚴格(ge)的(de)限制(因為只(zhi)(zhi)有一面(mian)(mian)(mian)，布(bu)線(xian)(xian)間不能交叉而(er)必須繞獨自的(de)路徑)，所(suo)(suo)以只(zhi)(zhi)有早期的(de)電(dian)路才使用這(zhe)(zhe)類的(de)板子。

　　雙面板

　　雙(shuang)面(mian)(mian)板(ban)(ban)(ban)(Double-Sided Boards) 這種電路(lu)(lu)板(ban)(ban)(ban)的(de)兩面(mian)(mian)都有布線(xian)，不過要用上(shang)兩面(mian)(mian)的(de)導線(xian)，必須要在(zai)(zai)兩面(mian)(mian)間有適當的(de)電路(lu)(lu)連接才(cai)行(xing)。這種電路(lu)(lu)間的(de)“橋梁”叫做(zuo)導孔(kong)(kong)(via)。導孔(kong)(kong)是(shi)在(zai)(zai)PCB上(shang)，充滿或涂上(shang)金屬(shu)的(de)小洞，它(ta)可以與兩面(mian)(mian)的(de)導線(xian)相(xiang)連接。因為雙(shuang)面(mian)(mian)板(ban)(ban)(ban)的(de)面(mian)(mian)積比單面(mian)(mian)板(ban)(ban)(ban)大了(le)一(yi)倍，雙(shuang)面(mian)(mian)板(ban)(ban)(ban)解決了(le)單面(mian)(mian)板(ban)(ban)(ban)中因為布線(xian)交錯(cuo)的(de)難(nan)點(可以通過孔(kong)(kong)導通到(dao)另一(yi)面(mian)(mian))，它(ta)更適合用在(zai)(zai)比單面(mian)(mian)板(ban)(ban)(ban)更復雜的(de)電路(lu)(lu)上(shang)。

　　多層板

　　多(duo)(duo)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)板(ban)(Multi-Layer Boards) 為了增加可以(yi)布線(xian)的(de)(de)面(mian)積，多(duo)(duo)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)板(ban)用(yong)上了更多(duo)(duo)單(dan)(dan)或雙面(mian)的(de)(de)布線(xian)板(ban)。用(yong)一(yi)塊雙面(mian)作內層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)、二(er)塊單(dan)(dan)面(mian)作外層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)或二(er)塊雙面(mian)作內層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)、二(er)塊單(dan)(dan)面(mian)作外層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)的(de)(de)印刷線(xian)路(lu)(lu)板(ban)，通過(guo)定位系(xi)統及絕緣粘結材料交(jiao)替(ti)在(zai)一(yi)起且導電(dian)圖形按(an)設計要(yao)求進(jin)行互連的(de)(de)印刷線(xian)路(lu)(lu)板(ban)就成為四(si)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)、六層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)印刷電(dian)路(lu)(lu)板(ban)了，也(ye)稱為多(duo)(duo)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)印刷線(xian)路(lu)(lu)板(ban)。板(ban)子的(de)(de)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)數并(bing)不代表(biao)有幾層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)獨(du)立的(de)(de)布線(xian)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)，在(zai)特(te)殊情況下會加入空層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)來控制板(ban)厚，通常層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)數都(dou)是偶(ou)數，并(bing)且包含(han)最外側的(de)(de)兩層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)。大(da)部分(fen)的(de)(de)主(zhu)機(ji)板(ban)都(dou)是4到(dao)(dao)8層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)的(de)(de)結構，不過(guo)技術上理論可以(yi)做到(dao)(dao)近100層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)的(de)(de)PCB板(ban)。大(da)型(xing)的(de)(de)超(chao)級(ji)計算機(ji)大(da)多(duo)(duo)使用(yong)相當(dang)多(duo)(duo)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)的(de)(de)主(zhu)機(ji)板(ban)，不過(guo)因(yin)為這類計算機(ji)已經可以(yi)用(yong)許多(duo)(duo)普通計算機(ji)的(de)(de)集群代替(ti)，超(chao)多(duo)(duo)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)板(ban)已經漸漸不被使用(yong)了。因(yin)為PCB中的(de)(de)各層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)都(dou)緊密的(de)(de)結合，一(yi)般(ban)不太容易(yi)看出實(shi)際數目(mu)，不過(guo)如果(guo)仔細觀察(cha)主(zhu)機(ji)板(ban)，還是可以(yi)看出來。