1, ukwahlulela kwekhwalithiI-MOSFETokuhle noma okubi
Umgomo wokubuyisela we-MOSFET nokwahlulela okuhle noma okubi, qala usebenzise ibhulokhi ye-multimeter R × 10kΩ (ibhethri elakhelwe ngaphakathi elingu-9V noma i-15V), ipeni elinegethivu (elimnyama) elixhunywe esangweni (G), ipeni elihle (elibomvu) elixhunywe kwi- umthombo (S). Uma ushaja phakathi kwesango nomthombo, i-multimeter pointer izophambuka kancane. Nakulokhu kusetshenziswa i-multimeter R × 1Ω block, ipeni elinegethivu ku-drain (D), ipeni elihle emthonjeni (S), i-multimeter ikhombisa inani lama-ohm ambalwa, okubonisa ukuthi i-MOSFET inhle.
2, ukuhlaziywa kwekhwalithi ye-electrode ye-MOSFET ye-junction
I-multimeter izoshayelwa kufayela elingu-R × 100, ipeni elibomvu kunoma iyiphi ishubhu eyodwa yonyawo, ipeni elimnyama liye kwelinye, ukuze unyawo lwesithathu lumiswe okwesikhashana. Uma uthola ukushwibeka kancane kwenaliti yemitha, fakazela ukuthi unyawo lwesithathu yisango. Uma ufuna ukuthola imiphumela esobala kakhulu, ungasebenzisa futhi umzimba oseduze noma ngomunwe ukuze uthinte unyawo olumisiwe, inqobo nje uma ubona inaliti ichezuke kakhulu, okusho ukuthi, okubonisa ukuthi unyawo olumisiwe lwesango, okusele izinyawo ezimbili zomthombo nokukhipha amanzi, ngokulandelana.
Izizathu zokucwasa:I-JFETukumelana okokufaka kukhulu kune-100MΩ, futhi i-transconductance iphakeme kakhulu, lapho isango livulekile-isifunda, insimu ye-electromagnetic yesikhala ingathonywa kalula isignali ye-voltage yesango, ukuze ishubhu livame ukunqanyulwa, noma livame ukuqhutshwa. Uma umzimba womuntu ngqo ku-voltage yokungeniswa kwesango, ngenxa yesignali yokuphazamiseka kokufaka inamandla, into engenhla izoba sobala kakhulu. Isibonelo, inaliti yokuchema kwesokunxele inkulu kakhulu, kusho ukuthi ishubhu livame ukunqamuka, ukumelana nomthombo we-RDS kuyanda, i-drain-source current inciphisa i-IDS. ngokuphambene, inaliti ohlangothini lwesokudla lokuchezuka okukhulu, ukuthi ithubhu ivame conduction, RDS ↓, IDS ↑. Kodwa-ke, ukuthi iyiphi inkomba enalithi yemitha echezuka ngempela kufanele kunqunywe i-polarity ye-voltage eyenziwe (i-voltage eya phambili noma ehlehlayo) kanye nendawo yokusebenza yeshubhu.
Izinyathelo zokuzivikela:
Imiphumela yokuhlolwa ibonisa ukuthi lapho izandla zombili zifakwe intuba ezigxotsheni zika-D no-S futhi kuthintwa isango kuphela, inaliti yemitha ngokuvamile ichezukela kwesokunxele. Nokho, lapho izandla zombili zithinta izigxobo zika-D no-S ngokulandelana futhi iminwe ithinta isango, inaliti yemitha ingabhekwa ukuze iphambukele kwesokudla. Isizathu salokhu ukuthi izingxenye eziningana zomzimba womuntu kanye nokumelana kukhethaI-MOSFETendaweni ye-saturation.
Ukunqunywa kwephinikhodi ye-Crystal triode
I-Triode yakhiwe umgogodla (izixhumanisi ezimbili ze-PN), ama-electrode amathathu negobolondo leshubhu, ama-electrode amathathu abizwa ngokuthi umqoqi c, emitter e, isisekelo b. Njengamanje, i-triode evamile iyishubhu ye-silicon planar, ephinde ihlukaniswe yaba izigaba ezimbili: uhlobo lwe-PNP nohlobo lwe-NPN. Amashubhu e-Germannium alloy manje ayivelakancane.
Lapha sizokwethula indlela elula yokusebenzisa i-multimeter ukukala izinyawo ze-triode ze-triode.
1, thola isigxobo esiyisisekelo, thola uhlobo lweshubhu (i-NPN noma i-PNP)
Ku-PNP-type triode, izigxobo ze-C kanye no-E ziyizigxobo eziqondile zezingxenye ezimbili ze-PN ngaphakathi kuyo, futhi i-B pole iyisigxobo sayo esivamile esinegethivu, kuyilapho i-NPN-type triode iphambene, izigxobo zika-C no-E ziyizigxobo ezingezinhle. yezingxenye ezimbili ze-PN, kanye ne-B pole iyisigxobo sayo esivamile, futhi kulula ukucacisa isigxobo sesisekelo kanye nohlobo lweshubhu ngokusho kwezimpawu zokumelana okuhle kwe-PN junction kuncane, futhi ukumelana okuphambene kukhulu. . Indlela eqondile yilena:
Sebenzisa i-multimeter edayelwe ku-R × 100 noma i-R × 1K igiya. Ipeni elibomvu thinta iphini, bese usebenzisa ipeni elimnyama lalixhunywe kwezinye izikhonkwane ezimbili, ukuze ukwazi ukuthola amaqembu amathathu (iqembu ngalinye lamabili) ukufundwa, lapho elinye lamaqoqo amabili okufundwa likunani eliphansi lokumelana ama-ohm angamakhulu ambalwa, uma izikhonkwane zomphakathi ziyipeni elibomvu, othintana naye yisisekelo, uhlobo lwe-transistor lohlobo lwe-PNP; uma izikhonkwane zomphakathi ziyipeni elimnyama, othintana naye yisisekelo, uhlobo lwe-transistor lohlobo lwe-NPN.
2, khomba umthumeli kanye nomqoqi
Njengokukhiqizwa kwe-triode, indawo emibili ye-P noma indawo emibili ye-N ngaphakathi kokuhlushwa kwe-doping ihlukile, uma i-amplifier elungile, i-triode ine-amplification eqinile, futhi okuphambene nalokho, nge-amplifier engalungile, i-amplifier yokukhulisa inani elikhulu elibuthakathaka kakhulu. , ngakho-ke i-triode ene-amplifier efanele, i-triode ene-amplifier engalungile, kuzoba nomehluko omkhulu.
Ngemva kokuhlonza uhlobo lweshubhu kanye nesisekelo b, umqoqi kanye ne-emitter bangabonakala ngendlela elandelayo. Dayela i-multimeter ngokucindezela u-R x 1K. Ncinza isisekelo kanye nephinikhodi ndawonye ngezandla zombili (qaphela ukuthi ungavumeli ama-electrode ahlangane ngqo). Ukuze wenze into yokulinganisa ibe sobala, manzisa iminwe yakho, cindezela ipeni elibomvu ngesisekelo, cindezela ipeni elimnyama ngomunye uphini, futhi unake ubukhulu bokushwibeka kwesokudla kwesikhombisi se-multimeter. Okulandelayo, lungisa izikhonkwane ezimbili, phinda izinyathelo zokulinganisa ezingenhla. Qhathanisa i-amplitude yokushwibeka yenaliti ezilinganisweni ezimbili futhi uthole ingxenye enobubanzi obukhudlwana. Kuma-transistors ohlobo lwe-PNP, xhuma ipeni elimnyama kuphini kanye nephinikhodi yesisekelo ndawonye, phinda izivivinyo ezingenhla ukuze uthole ukuthi i-amplitude yokushwibeka yenaliti inkulu kuphi, ngohlobo lwe-NPN, ipeni elimnyama lixhunywe esisekelweni, elibomvu. ipeni lixhunywe ku-emitter. Ohlotsheni lwe-PNP, ipeni elibomvu lixhunywe kumqoqi, ipeni elimnyama lixhunywe ku-emitter.
Umgomo wale ndlela yokuhlonza ukusebenzisa ibhethri ku-multimeter, i-voltage yengezwa kumqoqi kanye ne-emitter ye-transistor, ukuze ibe nekhono lokukhulisa. Isandla cindezela isisekelo sayo, umqoqi, olingana nokumelana nesandla ku-triode kanye ne-bias yamanje enhle, ukuze iqhube, ngalesi sikhathi ubukhulu benaliti yemitha ejikela kwesokudla bubonisa ikhono layo lokukhulisa, ukuze ukwazi kahle. nquma indawo ye-emitter, umqoqi.
Isikhathi sokuthumela: Apr-21-2024
