場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(guan)是(shi)場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)晶(jing)體(ti)(ti)(ti)管(guan)(guan)（FieldEffectTransistor,FET）的(de)簡稱(cheng)。它(ta)屬于電(dian)(dian)(dian)(dian)壓(ya)型半導體(ti)(ti)(ti)器件，具有輸入電(dian)(dian)(dian)(dian)阻(zu)高、噪聲小(xiao)、功(gong)耗(hao)低、沒有二(er)次擊(ji)穿現(xian)象、安全(quan)工作(zuo)(zuo)區域寬(kuan)、受溫度影響小(xiao)等(deng)，特別適用于高靈(ling)敏度和(he)低噪聲的(de)電(dian)(dian)(dian)(dian)路，現(xian)已成為普通晶(jing)體(ti)(ti)(ti)管(guan)(guan)的(de)強大競爭者。普通晶(jing)體(ti)(ti)(ti)管(guan)(guan)（三(san)(san)極(ji)管(guan)(guan)）是(shi)一(yi)種(zhong)電(dian)(dian)(dian)(dian)流元件，工作(zuo)(zuo)時，多數載流子(zi)和(he)少數載流子(zi)都(dou)參(can)與運行，所以(yi)(yi)被稱(cheng)為雙極(ji)型晶(jing)體(ti)(ti)(ti)管(guan)(guan)；而場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(guan)（FET）是(shi)一(yi)種(zhong)電(dian)(dian)(dian)(dian)壓(ya)器件（改(gai)變(bian)其柵源電(dian)(dian)(dian)(dian)壓(ya)就可(ke)以(yi)(yi)改(gai)變(bian)其漏極(ji)電(dian)(dian)(dian)(dian)流），工作(zuo)(zuo)時，只有一(yi)種(zhong)載流子(zi)參(can)與導電(dian)(dian)(dian)(dian)，因(yin)此它(ta)是(shi)單極(ji)型晶(jing)體(ti)(ti)(ti)管(guan)(guan)。場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(guan)和(he)三(san)(san)極(ji)管(guan)(guan)一(yi)樣(yang)都(dou)能實現(xian)信號的(de)和(he)放(fang)大，但由(you)于他們構造和(he)工作(zuo)(zuo)原(yuan)理截然不同，所以(yi)(yi)二(er)者的(de)差異很大。在某些特殊(shu)應(ying)(ying)(ying)用方面，場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(guan)優于三(san)(san)極(ji)管(guan)(guan)，是(shi)三(san)(san)極(ji)管(guan)(guan)無法替代的(de)。場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(guan)的(de)電(dian)(dian)(dian)(dian)壓(ya)放(fang)大倍數大。MOS場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(guan)用途(tu)

MOS場(chang)(chang)效應(ying)管的(de)測試方(fang)式(1)．打算工作測量之(zhi)前，先把人(ren)體(ti)對地短(duan)路(lu)(lu)(lu)后，才(cai)能(neng)摸觸(chu)MOSFET的(de)管腳(jiao)(jiao)。在(zai)(zai)手腕上接(jie)(jie)(jie)一(yi)(yi)(yi)條導線(xian)與(yu)大(da)地連(lian)接(jie)(jie)(jie)，使人(ren)體(ti)與(yu)大(da)地維持(chi)等電(dian)(dian)位。再把管腳(jiao)(jiao)分(fen)離，然(ran)后拆掉導線(xian)。(2)．判斷電(dian)(dian)極(ji)(ji)(ji)(ji)將(jiang)萬用表(biao)(biao)(biao)撥于R×100檔，首先確定柵(zha)極(ji)(ji)(ji)(ji)。若某(mou)腳(jiao)(jiao)與(yu)其它腳(jiao)(jiao)的(de)電(dian)(dian)阻都是無限大(da)，驗證此腳(jiao)(jiao)就是柵(zha)極(ji)(ji)(ji)(ji)G。交(jiao)換表(biao)(biao)(biao)筆重(zhong)測量，S-D之(zhi)間的(de)電(dian)(dian)阻值(zhi)應(ying)為幾(ji)百歐至幾(ji)千歐，其中(zhong)(zhong)阻值(zhi)較小的(de)那一(yi)(yi)(yi)次(ci)，黑表(biao)(biao)(biao)筆接(jie)(jie)(jie)的(de)為D極(ji)(ji)(ji)(ji)，紅表(biao)(biao)(biao)筆接(jie)(jie)(jie)的(de)是S極(ji)(ji)(ji)(ji)。日本生產(chan)的(de)3SK系(xi)列產(chan)品，S極(ji)(ji)(ji)(ji)與(yu)管殼接(jie)(jie)(jie)通(tong)，據此很(hen)容易確定S極(ji)(ji)(ji)(ji)。(3)．檢驗放大(da)能(neng)力(li)(跨導)將(jiang)G極(ji)(ji)(ji)(ji)懸(xuan)空(kong)，黑表(biao)(biao)(biao)筆接(jie)(jie)(jie)D極(ji)(ji)(ji)(ji)，紅表(biao)(biao)(biao)筆接(jie)(jie)(jie)S極(ji)(ji)(ji)(ji)，然(ran)后用指(zhi)頭觸(chu)摸G極(ji)(ji)(ji)(ji)，表(biao)(biao)(biao)針理應(ying)較大(da)的(de)偏轉(zhuan)。雙(shuang)柵(zha)MOS場(chang)(chang)效應(ying)管有(you)兩個(ge)柵(zha)極(ji)(ji)(ji)(ji)G1、G2。為區別之(zhi)，可(ke)用手分(fen)別觸(chu)摸G1、G2極(ji)(ji)(ji)(ji)，其中(zhong)(zhong)表(biao)(biao)(biao)針向左側偏轉(zhuan)大(da)幅度(du)較大(da)的(de)為G2極(ji)(ji)(ji)(ji)。目前有(you)的(de)MOSFET管在(zai)(zai)G-S極(ji)(ji)(ji)(ji)間增加了保護二極(ji)(ji)(ji)(ji)管，平時就不需要把各管腳(jiao)(jiao)短(duan)路(lu)(lu)(lu)了。MOS場(chang)(chang)效應(ying)晶體(ti)管在(zai)(zai)采用時應(ying)留意(yi)分(fen)類，不能(neng)隨心所欲交(jiao)換。MOS場(chang)(chang)效應(ying)晶體(ti)管由于輸入(ru)阻抗高(包(bao)括MOS集成電(dian)(dian)路(lu)(lu)(lu))極(ji)(ji)(ji)(ji)易被靜電(dian)(dian)擊穿，用到(dao)時應(ying)留意(yi)以下(xia)準(zhun)則：(1).MOS器件出廠時一(yi)(yi)(yi)般而言(yan)裝在(zai)(zai)黑色(se)的(de)導電(dian)(dian)泡沫塑料(liao)袋中(zhong)(zhong)，切勿自行隨意(yi)拿個(ge)塑料(liao)袋裝。也可(ke)用細銅(tong)線(xian)把各個(ge)引腳(jiao)(jiao)聯(lian)接(jie)(jie)(jie)在(zai)(zai)一(yi)(yi)(yi)起(qi)，或用錫紙包(bao)裝。上海(hai)絕緣柵(zha)型場(chang)(chang)效應(ying)管供(gong)應(ying)商電(dian)(dian)路(lu)(lu)(lu)將(jiang)一(yi)(yi)(yi)個(ge)增強型P溝(gou)道(dao)MOS場(chang)(chang)效應(ying)管和一(yi)(yi)(yi)個(ge)增強型N溝(gou)道(dao)MOS場(chang)(chang)效應(ying)管組合在(zai)(zai)一(yi)(yi)(yi)起(qi)使用。

場效應管在過渡層(ceng)(ceng)(ceng)由(you)(you)于(yu)沒有(you)電(dian)(dian)(dian)(dian)(dian)子(zi)(zi)、空穴的(de)(de)自由(you)(you)移(yi)動(dong)(dong)，在理想狀態下幾(ji)乎具有(you)絕緣特性(xing)，通常電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)也(ye)難流(liu)(liu)動(dong)(dong)。但(dan)是(shi)此(ci)時漏(lou)極(ji)(ji)-源極(ji)(ji)間的(de)(de)電(dian)(dian)(dian)(dian)(dian)場，實際上(shang)是(shi)兩(liang)個過渡層(ceng)(ceng)(ceng)接觸漏(lou)極(ji)(ji)與(yu)門極(ji)(ji)下部(bu)(bu)附(fu)近，由(you)(you)于(yu)漂移(yi)電(dian)(dian)(dian)(dian)(dian)場拉去的(de)(de)高速電(dian)(dian)(dian)(dian)(dian)子(zi)(zi)通過過渡層(ceng)(ceng)(ceng)。因(yin)漂移(yi)電(dian)(dian)(dian)(dian)(dian)場的(de)(de)強度幾(ji)乎不變產生ID的(de)(de)飽和現象。其次，VGS向負的(de)(de)方向變化，讓VGS=VGS(off)，此(ci)時過渡層(ceng)(ceng)(ceng)大(da)致成為覆蓋全區(qu)域的(de)(de)狀態。而且VDS的(de)(de)電(dian)(dian)(dian)(dian)(dian)場大(da)部(bu)(bu)分加到過渡層(ceng)(ceng)(ceng)上(shang)，將電(dian)(dian)(dian)(dian)(dian)子(zi)(zi)拉向漂移(yi)方向的(de)(de)電(dian)(dian)(dian)(dian)(dian)場，只有(you)靠近源極(ji)(ji)的(de)(de)很短部(bu)(bu)分，這更使電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)不能流(liu)(liu)通。

MOS場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)也(ye)(ye)(ye)被稱為金屬(shu)氧化物半(ban)(ban)導體(ti)(ti)場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)(MetalOxideSemiconductor FieldEffect Transistor, MOSFET)。它一般有耗盡型(xing)(xing)(xing)和(he)增強(qiang)型(xing)(xing)(xing)兩種。增強(qiang)型(xing)(xing)(xing)MOS場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)可分為NPN型(xing)(xing)(xing)PNP型(xing)(xing)(xing)。NPN型(xing)(xing)(xing)通常稱為N溝(gou)道型(xing)(xing)(xing)，PNP型(xing)(xing)(xing)也(ye)(ye)(ye)叫(jiao)P溝(gou)道型(xing)(xing)(xing)。對于N溝(gou)道的(de)(de)場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)其(qi)源極(ji)和(he)漏(lou)(lou)極(ji)接在(zai)N型(xing)(xing)(xing)半(ban)(ban)導體(ti)(ti)上，同樣對于P溝(gou)道的(de)(de)場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)其(qi)源極(ji)和(he)漏(lou)(lou)極(ji)則接在(zai)P型(xing)(xing)(xing)半(ban)(ban)導體(ti)(ti)上。場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)的(de)(de)輸出(chu)電流是由輸入(ru)的(de)(de)電壓（或稱電場(chang)(chang)(chang)）控制，可以認(ren)為輸入(ru)電流極(ji)小或沒(mei)有輸入(ru)電流，這使(shi)得該器件有很高(gao)的(de)(de)輸入(ru)阻抗，同時這也(ye)(ye)(ye)是我們(men)稱之(zhi)為場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)的(de)(de)原因。場(chang)(chang)(chang)效(xiao)應(ying)(ying)(ying)管(guan)的(de)(de)尺寸小，適合集(ji)成電路應(ying)(ying)(ying)用。

場效應(ying)管MOSFET分(fen)類MOSFET分(fen)為兩大(da)類：N溝道(dao)和P溝道(dao)。在(zai)(zai)功(gong)(gong)率系統(tong)中，MOSFET起到(dao)的(de)作用相(xiang)當(dang)(dang)于(yu)一個(ge)(ge)開關(guan)(guan)。當(dang)(dang)在(zai)(zai)N溝道(dao)MOSFET的(de)柵(zha)(zha)極(ji)(ji)(ji)和源(yuan)(yuan)極(ji)(ji)(ji)間加(jia)上正(zheng)電(dian)(dian)(dian)壓時(shi)，其開關(guan)(guan)導(dao)通(tong)(tong)(tong)。導(dao)通(tong)(tong)(tong)時(shi)，電(dian)(dian)(dian)流(liu)可經(jing)開關(guan)(guan)從漏極(ji)(ji)(ji)流(liu)向源(yuan)(yuan)極(ji)(ji)(ji)。漏極(ji)(ji)(ji)和源(yuan)(yuan)極(ji)(ji)(ji)之間存在(zai)(zai)一個(ge)(ge)內阻，稱為導(dao)通(tong)(tong)(tong)電(dian)(dian)(dian)阻RDS（ON）。必須(xu)清楚MOSFET的(de)柵(zha)(zha)極(ji)(ji)(ji)是個(ge)(ge)高阻抗端，因此，總 是要(yao)在(zai)(zai)柵(zha)(zha)極(ji)(ji)(ji)加(jia)上一個(ge)(ge)電(dian)(dian)(dian)壓。如(ru)果(guo)柵(zha)(zha)極(ji)(ji)(ji)為懸空，器(qi)件將(jiang)不(bu)能(neng)按(an)設計意圖(tu)工作，并可能(neng)在(zai)(zai)不(bu)恰當(dang)(dang)的(de)時(shi)刻導(dao)通(tong)(tong)(tong)或(huo)關(guan)(guan)閉，導(dao)致系統(tong)產生(sheng)潛在(zai)(zai)的(de)功(gong)(gong)率損耗(hao)。當(dang)(dang)源(yuan)(yuan)極(ji)(ji)(ji)和柵(zha)(zha)極(ji)(ji)(ji)間的(de)電(dian)(dian)(dian) 壓為零時(shi)，開關(guan)(guan)關(guan)(guan)閉，而電(dian)(dian)(dian)流(liu)停(ting)止通(tong)(tong)(tong)過(guo)器(qi)件。雖然(ran)這時(shi)器(qi)件已經(jing)關(guan)(guan)閉，但仍然(ran)有(you)微小電(dian)(dian)(dian)流(liu)存在(zai)(zai)，這稱之為漏電(dian)(dian)(dian)流(liu)，即(ji)IDSS。場效應(ying)管的(de)性能(neng)受溫度影響(xiang)較大(da)。杭州半導(dao)體場效應(ying)管市場價(jia)

場(chang)效(xiao)應管可應用于放大。MOS場(chang)效(xiao)應管用途(tu)

如果我(wo)們在(zai)上面這個(ge)(ge)(ge)圖中,將電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻Rc換(huan)成(cheng)一個(ge)(ge)(ge)燈(deng)泡(pao)(pao),那(nei)么當基極電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)為(wei)(wei)0時(shi),集電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)為(wei)(wei)0,燈(deng)泡(pao)(pao)滅.如果基極電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)比較大(da)(da)時(shi)(大(da)(da)于流(liu)(liu)過燈(deng)泡(pao)(pao)的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)除以(yi)(yi)(yi)三極管(guan)(guan) 的(de)放大(da)(da)倍數(shu) β),三極管(guan)(guan)就(jiu)飽和(he),相(xiang)當于開(kai)(kai)關(guan)閉(bi)合,燈(deng)泡(pao)(pao)就(jiu)亮(liang)了(le).由于電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)只需(xu)要比燈(deng)泡(pao)(pao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)β分之(zhi)一大(da)(da)一點就(jiu)行(xing)了(le),所(suo)以(yi)(yi)(yi)就(jiu)可(ke)(ke)以(yi)(yi)(yi)用(yong)一個(ge)(ge)(ge)小電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)來(lai)一個(ge)(ge)(ge)大(da)(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)通 斷(duan).如果基極電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)從0慢(man)慢(man)增(zeng)加,那(nei)么燈(deng)泡(pao)(pao)的(de)亮(liang)度也(ye)會隨著增(zeng)加(在(zai)三極管(guan)(guan)未飽和(he)之(zhi)極管(guan)(guan)開(kai)(kai)關(guan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路由開(kai)(kai)關(guan)三極管(guan)(guan)VT，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)動(dong)機M，開(kai)(kai)關(guan)S，基極限流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻器R和(he)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源GB組成(cheng)。VT采用(yong)NPN型小功率(lv)硅管(guan)(guan)8050，其(qi)集電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極最(zui)大(da)(da)允許(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)ICM可(ke)(ke)達1.5A，以(yi)(yi)(yi)滿足電(dian)(dian)(dian)(dian)(dian)(dian)(dian)動(dong)機起動(dong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)要求。M選用(yong)工作電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓為(wei)(wei)3V的(de)小型直流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)動(dong)機，對應電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源GB亦為(wei)(wei)3V。MOS場效應管(guan)(guan)用(yong)途

本文來自四川精碳(tan)偉(wei)業(ye)環保(bao)科技有限責任公司：//wasul.cn/Article/9b20799783.html