固定電阻器有多種類型，選擇哪一種材料和結構的電阻器，應根據應用電路的具體要求而定。

高(gao)頻電路(lu)應選用分布電感和(he)分布電容小的非線(xian)繞電阻(zu)(zu)器(qi)，例如碳膜(mo)(mo)電阻(zu)(zu)器(qi)、金屬電阻(zu)(zu)器(qi)和(he)金屬氧化膜(mo)(mo)電阻(zu)(zu)器(qi)等。

高增益小信(xin)號放(fang)大電(dian)(dian)(dian)路應選用(yong)低噪聲電(dian)(dian)(dian)阻器，例如金(jin)屬膜(mo)(mo)電(dian)(dian)(dian)阻器、碳膜(mo)(mo)電(dian)(dian)(dian)阻器和線繞電(dian)(dian)(dian)阻器，而(er)不能(neng)使用(yong)噪聲較大的合成碳膜(mo)(mo)電(dian)(dian)(dian)阻器和有機實(shi)心(xin)電(dian)(dian)(dian)阻器。

線繞電(dian)(dian)阻(zu)(zu)器(qi)(qi)的功率較大，電(dian)(dian)流(liu)噪聲小，耐(nai)高溫，但(dan)體(ti)積(ji)較大。普通線繞電(dian)(dian)阻(zu)(zu)器(qi)(qi)常用于(yu)低(di)頻電(dian)(dian)路或(huo)中作(zuo)限流(liu)電(dian)(dian)阻(zu)(zu)器(qi)(qi)、分(fen)壓電(dian)(dian)阻(zu)(zu)器(qi)(qi)、泄(xie)放電(dian)(dian)阻(zu)(zu)器(qi)(qi)或(huo)大功率管的偏壓電(dian)(dian)阻(zu)(zu)器(qi)(qi)。精度較高的線繞電(dian)(dian)阻(zu)(zu)器(qi)(qi)多用于(yu)固定衰(shuai)減器(qi)(qi)、電(dian)(dian)阻(zu)(zu)箱、計算機及各種精密電(dian)(dian)子儀(yi)器(qi)(qi)中。

所選電(dian)阻(zu)器(qi)(qi)(qi)的(de)(de)電(dian)阻(zu)值應(ying)接近(jin)應(ying)用(yong)電(dian)路中計(ji)算(suan)值的(de)(de)一(yi)個標稱值，應(ying)優先(xian)選用(yong)標準系列的(de)(de)電(dian)阻(zu)器(qi)(qi)(qi)。一(yi)般電(dian)路使用(yong)的(de)(de)電(dian)阻(zu)器(qi)(qi)(qi)允許(xu)誤差為±5%~±10%。精密儀器(qi)(qi)(qi)及特殊(shu)電(dian)路中使用(yong)的(de)(de)電(dian)阻(zu)器(qi)(qi)(qi)，應(ying)選用(yong)精密電(dian)阻(zu)器(qi)(qi)(qi)。

所選(xuan)電阻(zu)器的(de)額定功(gong)(gong)(gong)率，要(yao)符合(he)應用電路(lu)中對電阻(zu)器功(gong)(gong)(gong)率容量的(de)要(yao)求(qiu)，一般不應隨意加大或減小電阻(zu)器的(de)功(gong)(gong)(gong)率。若電路(lu)要(yao)求(qiu)是(shi)功(gong)(gong)(gong)率型電阻(zu)器，則其額定功(gong)(gong)(gong)率可高(gao)于實際應用電路(lu)要(yao)求(qiu)功(gong)(gong)(gong)率的(de)1~2倍。

文章源自：貼片電阻、固定電阻器、旺詮合金電阻、旺詮(quan)合(he)金電阻代理商