一、光耦的作用是什么
光(guang)耦(ou)(ou)(ou)(ou)是光(guang)電(dian)(dian)耦(ou)(ou)(ou)(ou)合(he)器的簡稱,又叫光(guang)耦(ou)(ou)(ou)(ou)合(he)器,是以光(guang)為(wei)媒介(jie)傳(chuan)輸(shu)(shu)電(dian)(dian)信(xin)號的一種電(dian)(dian)一光(guang)一電(dian)(dian)轉換器件,它通過發(fa)光(guang)二極管(LED)、受(shou)(shou)控光(guang)源或激光(guang)作(zuo)為(wei)光(guang)源,將(jiang)輸(shu)(shu)入的電(dian)(dian)信(xin)號轉換成光(guang)信(xin)號輸(shu)(shu)出(chu),以實現電(dian)(dian)信(xin)號的調(diao)制(zhi)與轉換,其主要作(zuo)用(yong)有:1、有效隔離電(dian)(dian)氣上的輸(shu)(shu)入和輸(shu)(shu)出(chu)電(dian)(dian)路(lu)。2、使(shi)信(xin)號可以以光(guang)的形式傳(chuan)輸(shu)(shu),具有良好的抗干擾(rao)效果。3、起保護作(zuo)用(yong),當(dang)光(guang)耦(ou)(ou)(ou)(ou)合(he)器的輸(shu)(shu)入側(ce)受(shou)(shou)到強電(dian)(dian)壓(ya)沖擊而損壞時,由于光(guang)耦(ou)(ou)(ou)(ou)合(he)器的隔離作(zuo)用(yong),不會損壞輸(shu)(shu)出(chu)側(ce)電(dian)(dian)路(lu)。
二、光耦工作原理是什么
光(guang)(guang)耦(ou)合器一般由(you)光(guang)(guang)的(de)發(fa)射部(bu)分(發(fa)光(guang)(guang)器件(jian)(jian))、接(jie)(jie)收(shou)部(bu)分(光(guang)(guang)敏(min)器件(jian)(jian))以(yi)及信號放(fang)(fang)大部(bu)分(電(dian)(dian)子(zi)電(dian)(dian)路)三部(bu)分組(zu)成(cheng)(cheng),其工(gong)作原(yuan)理是:以(yi)發(fa)光(guang)(guang)器件(jian)(jian)的(de)管(guan)腳為(wei)輸(shu)(shu)入端,光(guang)(guang)敏(min)器件(jian)(jian)的(de)管(guan)腳為(wei)輸(shu)(shu)出(chu)(chu)端,工(gong)作時把(ba)電(dian)(dian)信號加(jia)到輸(shu)(shu)入端,使發(fa)光(guang)(guang)器件(jian)(jian)的(de)芯體發(fa)光(guang)(guang),而光(guang)(guang)敏(min)器件(jian)(jian)受光(guang)(guang)照后產生光(guang)(guang)電(dian)(dian)流并經電(dian)(dian)子(zi)電(dian)(dian)路放(fang)(fang)大后輸(shu)(shu)出(chu)(chu),實現電(dian)(dian)→光(guang)(guang)→電(dian)(dian)的(de)轉換,從(cong)而起到輸(shu)(shu)入、輸(shu)(shu)出(chu)(chu)、隔離的(de)作用(yong)。簡單(dan)來說,就(jiu)是輸(shu)(shu)入的(de)電(dian)(dian)信號驅動發(fa)光(guang)(guang)二極管(guan),使之發(fa)出(chu)(chu)一定波長的(de)光(guang)(guang),被光(guang)(guang)探測器接(jie)(jie)收(shou)而產生光(guang)(guang)電(dian)(dian)流,再經過進(jin)一步(bu)放(fang)(fang)大后輸(shu)(shu)出(chu)(chu),這就(jiu)完(wan)成(cheng)(cheng)了電(dian)(dian)→光(guang)(guang)→電(dian)(dian)的(de)轉換。
三、光耦怎么測好壞
光耦的好壞判斷,一般可以通過在路測量其內部二極管和三極管的正反向電阻來確定,如果想獲得更可靠的檢測結果,可以采取下面三種檢測方法:1、比較法:拆下懷疑有問題的光耦,用萬用表測量其內部二極管、三極管的正反向電阻值,用其與好的光耦對應腳的測量值進行比較,若阻值相差較大,則說明光耦已損壞。2、數字萬用表檢測法:將光耦內接二極管的+端{1}腳和-端{2}腳分別插入數字萬用表的Hfe 的c、e插孔內,此時數字萬用表應置于NPN擋;然后將光耦內接光電三極管C極{5}腳接指針式萬用表的黑表筆,e極{4}腳接紅表筆,并將指針式萬用表撥在RX1k擋。這樣就能通過指針式萬用表指針的偏轉角度——實際上是光電流的變化,來判斷光耦的情況。指針向右偏轉角度越大,說明光耦的光電轉換效率越高,即傳輸比越高,反之越低;若表針不動,則說明光耦已損壞。3、光電效應判斷法:將萬用表置于RX1k電阻擋,兩表筆分別接在光耦的輸出端{4}、{5}腳;然后用一節1.5V的電池與一只50~100Ω的電阻串接后,電池的正極端接EL817的{1}腳,負極端碰接{2}腳,或者正極端碰接{1}腳,負極端接{2}腳,這時觀察接在輸出端萬用表的指針偏轉情況。如果指針擺動,說明光耦是好的,如果不擺動,則說明光耦已損壞。萬用表指針擺動偏轉角度越大,表明光電轉換靈敏度越高。損壞的光耦需要及時更換,如果您需要采購光耦,可以先來了解一下光耦十大品牌。
四、光耦隔離是什么意思
光(guang)(guang)耦是(shi)光(guang)(guang)電(dian)(dian)耦合器,用(yong)(yong)于(yu)實(shi)現(xian)光(guang)(guang)電(dian)(dian)轉(zhuan)換,光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li),顧名思義就是(shi)利用(yong)(yong)光(guang)(guang)耦合器進(jin)行隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li),常用(yong)(yong)于(yu)信(xin)(xin)號(hao)隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)或光(guang)(guang)電(dian)(dian)的(de)(de)(de)(de)隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)。光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)的(de)(de)(de)(de)作(zuo)(zuo)用(yong)(yong)主要(yao)有兩點:1、隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)作(zuo)(zuo)用(yong)(yong):光(guang)(guang)耦可以(yi)起到(dao)信(xin)(xin)號(hao)的(de)(de)(de)(de)隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)作(zuo)(zuo)用(yong)(yong),因此光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)傳(chuan)輸(shu)出(chu)(chu)來(lai)的(de)(de)(de)(de)信(xin)(xin)號(hao)有著(zhu)單(dan)向傳(chuan)輸(shu)的(de)(de)(de)(de)特點,因此可以(yi)實(shi)現(xian)信(xin)(xin)號(hao)的(de)(de)(de)(de)單(dan)向傳(chuan)輸(shu),從(cong)而使(shi)得輸(shu)入(ru)端(duan)(duan)以(yi)及輸(shu)出(chu)(chu)端(duan)(duan)實(shi)現(xian)了電(dian)(dian)氣隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)。輸(shu)出(chu)(chu)線號(hao)對于(yu)輸(shu)入(ru)端(duan)(duan)不會(hui)產(chan)生影(ying)響,抗(kang)干(gan)(gan)擾的(de)(de)(de)(de)能(neng)力強,并(bing)且工作(zuo)(zuo)穩(wen)定。2、電(dian)(dian)平轉(zhuan)換作(zuo)(zuo)用(yong)(yong):光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)還可以(yi)實(shi)現(xian)電(dian)(dian)平的(de)(de)(de)(de)轉(zhuan)換作(zuo)(zuo)用(yong)(yong)。就好比單(dan)片機是(shi)采(cai)用(yong)(yong)3.3伏(fu)進(jin)行供電(dian)(dian)的(de)(de)(de)(de),那么(me)我們就需要(yao)輸(shu)出(chu)(chu)5伏(fu)電(dian)(dian)壓(ya)的(de)(de)(de)(de)方波,從(cong)而確(que)保(bao)光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)起到(dao)了電(dian)(dian)平轉(zhuan)換作(zuo)(zuo)用(yong)(yong)。光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)具有占空(kong)比任意可調(diao)、隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)耐壓(ya)高、抗(kang)干(gan)(gan)擾能(neng)力強、抗(kang)干(gan)(gan)擾能(neng)力強廣等(deng)優(you)點,不過它同樣也(ye)存在(zai)傳(chuan)輸(shu)延遲較(jiao)(jiao)大、開關速度較(jiao)(jiao)慢(man)、成本較(jiao)(jiao)高等(deng)缺點。