分享環形穿心電容的選購技巧有哪些呢？一起和小編來看看吧。
1、在選(xuan)購的(de)時候，首(shou)先耐壓(ya)問題是在選(xuan)購環形穿心電(dian)(dian)容(rong)過程中首(shou)先要(yao)考慮的(de)問題，如果夾在電(dian)(dian)容(rong)兩端(duan)的(de)電(dian)(dian)壓(ya)超過了電(dian)(dian)容(rong)的(de)額定(ding)電(dian)(dian)壓(ya)那么電(dian)(dian)容(rong)就會被(bei)擊(ji)穿，產(chan)品(pin)也會因此造成損(sun)壞。
2、環(huan)形穿(chuan)(chuan)心電(dian)容自(zi)電(dian)感(gan)較普(pu)通(tong)電(dian)容小得(de)多(duo)，故而自(zi)諧振頻率很高(gao)。同時，穿(chuan)(chuan)心式設計，也(ye)有效地防止了(le)高(gao)頻信號從(cong)輸入端直(zhi)接耦合到輸出端。這種低通(tong)高(gao)阻(zu)的(de)組合，在 1GHz 頻率范圍內，提供了(le)極(ji)好的(de)效果。 選購時一定(ding)要測試是足夠有的(de)相應的(de)容量。
3、接下來就是(shi)電容的封裝規格問題，小(xiao)體積(ji)通(tong)常做(zuo)小(xiao)耐(nai)壓(ya)(ya)，大(da)(da)體積(ji)做(zuo)高耐(nai)壓(ya)(ya)，體積(ji)的大(da)(da)小(xiao)一般也要根據電路(lu)板的設計來選購(gou)。
4、要(yao)考慮到電路要(yao)求選(xuan)擇環形穿心電容(rong)的(de)(de)類(lei)型(xing)。對于要(yao)求不(bu)高的(de)(de)低(di)頻電路和直流電路，一(yi)般可(ke)選(xuan)用紙(zhi)介電容(rong)器(qi)，也(ye)可(ke)選(xuan)用低(di)頻瓷(ci)介電容(rong)器(qi)。
5、在定時電路(lu)、振(zhen)蕩(dang)回路(lu)及音調(diao)控制(zhi)等電路(lu)中，對環(huan)形(xing)穿心電容的(de)電容量(liang)要(yao)求(qiu)較為嚴格(ge)，因此選(xuan)(xuan)取電容量(liang)的(de)標稱(cheng)值應盡量(liang)與計算的(de)電容值相(xiang)一(yi)致(zhi)或盡量(liang)接(jie)近，應盡量(liang)選(xuan)(xuan)精度(du)高(gao)的(de)電容器(qi)。在一(yi)些(xie)特殊的(de)電路(lu)中，往往對電容器(qi)的(de)電容量(liang)要(yao)求(qiu)非常(chang)準確，此時應選(xuan)(xuan)用允許偏差在±0．1％～±0．5％范圍內的(de)高(gao)精度(du)電容器(qi)。
以上(shang)幾(ji)點都沒有(you)問題后(hou)再(zai)要考慮的(de)(de)就是產品的(de)(de)誤(wu)差與材質。如(ru)果是常規(gui)的(de)(de)，在(zai)生產的(de)(de)物料，需要告知供應商以上(shang)電(dian)容的(de)(de)幾(ji)個(ge)重要參數(shu)、數(shu)量、品牌(pai)、貨期、品質、規(gui)格書、付款條件等(deng)等(deng)。(選購人員在購買(mai)產品時(shi)請認真核對好相關參數，這樣才可選購到合(he)適的高品質貼片電容)
隨著電(dian)子(zi)信息技術的(de)飛速發展，數字電(dian)子(zi)產品(pin)的(de)更新速度越(yue)來(lai)越(yue)快。消(xiao)費類電(dian)子(zi)產品(pin)產銷持續增長，主(zhu)要是(shi)平板電(dian)視（LCD和(he)PDP）、筆記本(ben)電(dian)腦、數碼相機等產品(pin)，帶動了電(dian)容(rong)器行業(ye)的(de)增長。下面是(shi)穿心電(dian)容(rong)生產廠家小編(bian)有關(guan)穿心電(dian)容(rong)的(de)公式具(ju)體計算法(fa)介紹(shao)：
電(dian)(dian)(dian)(dian)容(rong)是保(bao)持電(dian)(dian)(dian)(dian)荷的(de)能(neng)力。任何靜電(dian)(dian)(dian)(dian)場都(dou)是由許多電(dian)(dian)(dian)(dian)容(rong)器組成的(de)。如(ru)果(guo)有靜電(dian)(dian)(dian)(dian)場，就會有電(dian)(dian)(dian)(dian)容(rong)。電(dian)(dian)(dian)(dian)容(rong)用(yong)靜電(dian)(dian)(dian)(dian)場來描述。一(yi)般認(ren)為(wei)，絕緣導(dao)體(ti)和無限大構成電(dian)(dian)(dian)(dian)容(rong)，導(dao)體(ti)接地相(xiang)當于連接到無限大，連接到整體(ti)。
電(dian)容公式為(wei)(wei)(wei)：C=εS/4πkd 。式中，ε為(wei)(wei)(wei)常(chang)數(shu)，s為(wei)(wei)(wei)電(dian)容板的(de)(de)正面積，D為(wei)(wei)(wei)電(dian)容板的(de)(de)距(ju)離，K為(wei)(wei)(wei)靜電(dian)常(chang)數(shu)。普通平行板電(dian)容器，電(dian)容為(wei)(wei)(wei)C=εs/D（ε為(wei)(wei)(wei)板間介(jie)質的(de)(de)介(jie)電(dian)常(chang)數(shu)，s為(wei)(wei)(wei)板面積，D為(wei)(wei)(wei)板間距(ju)離）。
當(dang)(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)(qi)兩(liang)端電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓u的(de)(de)(de)參考方(fang)向(xiang)給定時(shi)(shi)，如果用q表示(shi)參考正電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)位(wei)板上(shang)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)量(liang)，則電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)(qi)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)量(liang)和(he)(he)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓滿足q=Cu。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)等于單位(wei)時(shi)(shi)間內通過(guo)某一截面(mian)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)量(liang)，得到I=DQ/DT，因(yin)此(ci)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)與電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)的(de)(de)(de)關系為I=DQ/DT=C（DU/DT）。公式表明電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)(de)(de)大(da)小和(he)(he)方(fang)向(xiang)取(qu)決于電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓隨(sui)時(shi)(shi)間的(de)(de)(de)變(bian)化(hua)率。當(dang)(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓升高時(shi)(shi)，Du/dt 0，DQ/dt0，i0，極(ji)板上(shang)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)增大(da)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)(qi)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)；當(dang)(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓降低時(shi)(shi)，Du/dt0，DQ/dt0，i0，極(ji)板上(shang)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)減小，容(rong)(rong)器(qi)(qi)反向(xiang)放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。當(dang)(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓不隨(sui)時(shi)(shi)間變(bian)化(hua)時(shi)(shi)，Du/dt=0，則電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)I=0，則電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)(qi)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)等于零，相當(dang)(dang)于開路。因(yin)此(ci)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)(qi)具(ju)有直流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)功(gong)能。
