Uhlolojikelele lwe-MOSFET

I-Power MOSFET nayo ihlukaniswe yaba uhlobo lwe-junction kanye nohlobo lwesango elivalekile, kodwa ngokuvamile libhekisela ohlotsheni lwesango elivalekile i-MOSFET (Metal Oxide Semiconductor FET), ebizwa ngokuthi amandla MOSFET (Amandla MOSFET). I-Junction Power field effect transistor ngokuvamile ibizwa ngokuthi i-electrostatic induction transistor (Static Induction Transistor - SIT). Ibonakala nge-voltage yesango ukuze ilawule i-drain current, i-drive circuit ilula, idinga amandla amancane okushayela, isivinini sokushintsha ngokushesha, imvamisa yokusebenza ephezulu, ukuzinza kwe-thermal kungcono kune-I-GTR, kodwa amandla ayo amanje mancane, amandla kagesi aphansi, ngokuvamile asebenza kuphela emandleni angekho ngaphezu kuka-10kW wamandla kagesi.

1. Isakhiwo se-MOSFET samandla kanye nomgomo wokusebenza

Izinhlobo ze-MOSFET zamandla: ngokusho kwesiteshi sokuqhuba zingahlukaniswa zibe yi-P-channel ne-N-channel. Ngokusho kwesango le-voltage amplitude ingahlukaniswa ibe; uhlobo lokuncipha; lapho i-voltage yesango inguziro lapho isigxobo somthombo wokukhipha amanzi phakathi kokuba khona kweshaneli yokuqhuba, sithuthukiswa; kudivayisi yesiteshi esingu-N (P), i-voltage yesango inkulu kunoziro (ngaphansi) ngaphambi kokuba khona kweshaneli eqhubayo, amandla e-MOSFET ngokuyinhloko athuthukiswa isiteshi esingu-N.

1.1 AmandlaI-MOSFETisakhiwo　　

Isakhiwo sangaphakathi se-MOSFET samandla nezimpawu zikagesi; conduction yayo eyodwa kuphela polarity abathwali (polys) ehilelekile conductive, kuyinto transistor unipolar. Indlela yokuqhuba iyafana ne-MOSFET enamandla aphansi, kodwa isakhiwo sinomehluko omkhulu, i-MOSFET enamandla aphansi iyisisetshenziswa esivundlile esivundlile, amandla e-MOSFET iningi lesakhiwo esima mpo, esikwaziwa nangokuthi i-VMOSFET (Vertical MOSFET) , okuthuthukisa kakhulu amandla kagesi wedivayisi ye-MOSFET nekhono lamanje lokumelana.

Ngokomehluko wesakhiwo sokuqhuba esime mpo, kodwa futhi ihlukaniswe ngokusetshenziswa kwe-groove emise okwe-V ukuze kuzuzwe ukuqhutshwa okuqondile kwe-VVMOSFET futhi inesakhiwo se-MOSFET esiphindwe kabili esihlukaniswe kabili se-VDMOSFET (Vertical Double-diffusedI-MOSFET), leli phepha lixoxwa kakhulu njengesibonelo samadivayisi we-VDMOS.

Ama-MOSFET Amandla ezakhiwo eziningi ezididiyelwe, njenge-International Rectifier (I-International Rectifier) ​​i-HEXFET esebenzisa iyunithi ene-hexagonal; I-Siemens (Siemens) SIPMOSFET isebenzisa iyunithi yesikwele; I-Motorola (Motorola) TMOS isebenzisa iyunithi engunxande ngohlelo lomumo othi "Phini".

1.2 Umgomo wokusebenza kwe-MOSFET yamandla

Ukunqamula: phakathi kwezigxobo zomthombo wokukhipha amanzi kanye nokuphakelwa kwamandla kagesi, izigxobo zomthombo wesango phakathi kwe-voltage nguziro. p base region kanye nesifunda se-N drift esakhiwe phakathi kwe-PN junction J1 reverse bias, akukho ukugeleza kwamanje phakathi kwezigxobo zomthombo wokukhipha amanzi.

I-Conductivity: Nge-voltage ephozithivu ye-UGS esetshenziswa phakathi kwamatheminali omthombo wesango, isango livalekile, ngakho akukho ukugeleza kwamanje kwesango. Kodwa-ke, amandla kagesi aqondile wesango azophusha izimbobo ku-P-region ngaphansi kwawo, futhi ahehe ama-oligons-electron aku-P-region ebusweni be-P-region ngaphansi kwesango lapho i-UGS inkulu kune- I-UT (i-voltage yokuvula noma i-threshold voltage), ukuhlushwa kwama-electron ebusweni besifunda se-P ngaphansi kwesango kuyoba ngaphezu kokugxila kwezimbobo, ukuze i-semiconductor yohlobo lwe-P iguqulelwe ohlotsheni lwe-N futhi ibe ungqimba oluhlanekezelwe, futhi isendlalelo esihlanekezelwe sakha i-N-channel futhi yenze ukuhlangana kwe-PN J1 kunyamalale, kudonse amanzi kanye nokuhamba komthombo.

1.3 Izimpawu Eziyisisekelo zama-MOSFET Amandla

1.3.1 Izimo ezimile.

Ubudlelwano phakathi kwe-ID yamanje yokudonsa kanye ne-voltage UGS phakathi komthombo wesango bubizwa ngokuthi isici sokudlulisa se-MOSFET, i-ID inkulu, ubudlelwano phakathi kwe-ID ne-UGS cishe buwumugqa, futhi umthambeka wejika uchazwa njenge-transconductance Gfs. .

Izici ze-drain volt-ampere (izici zokukhiphayo) ze-MOSFET: isifunda esinqamukile (okuhambisana nendawo yokusika ye-GTR); isifunda sokugcwala (okuhambisana nesifunda sokukhulisa i-GTR); isifunda esingagcwalisi (okuhambisana nesifunda sokugcwala kwe-GTR). Amandla e-MOSFET asebenza esimweni sokushintsha, okungukuthi, ashintsha aye emuva naphambili phakathi kwesifunda esinqamukile kanye nesifunda esingagcwalisi. Amandla e-MOSFET ane-diode ye-parasitic phakathi kwamatheminali akhipha amanzi, futhi idivayisi iqhuba lapho kusetshenziswa i-voltage ehlehlayo phakathi kwamatheminali omthombo wokukhipha amanzi. Ukumelana nesimo samandla we-MOSFET kune-coefficient yokushisa ephozithivu, evuna ukulinganisa okwamanje lapho amadivayisi axhumeke ngokuhambisana.

1.3.2 Izinhlamvu Ezinamandla;

Isifunda sayo sokuhlola kanye namagagasi enqubo yokushintsha.

Inqubo yokuvula; vula isikhathi sokulibaziseka td(on) - isikhathi esiphakathi kwesikhathi sokuqala nesikhathi lapho uGS = UT kanye ne-iD kuqala ukuvela; isikhathi sokukhuphuka t- isikhathi lapho i-uGS ikhuphuka isuka e-uT iye kugesi wesango i-UGSP lapho i-MOSFET ingena khona endaweni engagcwele; inani lesimo esizinzile se-iD linqunywa amandla kagesi okukhipha amanzi, i-UE, kanye ne-drain Ubukhulu be-UGSP buhlobene nevelu yesimo esizinzile se-iD. Ngemuva kokuthi i-UGS ifinyelele ku-UGSP, iyaqhubeka nokukhuphuka ngaphansi kwesenzo sokukhuphuka ize ifinyelele esimweni esiqinile, kodwa i-iD ayishintshile. Isikhathi sokuvula i-ton-Isamba sesikhathi sokulibaziseka sokukhanyisa nesikhathi sokukhuphuka.

Isikhathi sokulibaziseka sokuvala td(off) -Isikhathi lapho i-iD iqala ukwehla iye kuziro kusukela ngesikhathi ikhuphuka ifika kuqanda, i-Cin ikhishwa ngama-Rs kanye ne-RG, futhi i-uGS iwela ku-UGSP ngokuya ngejika elichazayo.

Isikhathi sokuwa tf- Isikhathi esisuka lapho i-uGS iqhubeka nokuwa ku-UGSP futhi i-iD siyehla kuze kube yilapho isiteshi sinyamalala ku-uGS < UT futhi i-ID iwela kuqanda. I-turn-off time toff- Isamba sesikhathi sokulibaziseka sokuvala kanye nesikhathi sokuwa.

1.3.3 Isivinini sokushintshwa kwe-MOSFET.

Isivinini sokushintshwa kwe-MOSFET kanye nokushaja nokukhishwa kwe-Cin kunobuhlobo obuhle, umsebenzisi akakwazi ukunciphisa i-Cin, kodwa anganciphisa umjikelezo wokushayela wangaphakathi ukumelana nama-Rs ukunciphisa isikhathi esingaguquki, ukusheshisa isivinini sokushintsha, i-MOSFET ithembele kuphela ku-polytronic conductivity, awukho umphumela wokugcina we-oligotronic, futhi ngaleyo ndlela inqubo yokuvala ishesha kakhulu, isikhathi sokushintsha se-10-100ns, imvamisa yokusebenza ingaba kufika ku-100kHz noma ngaphezulu, iyona ephezulu kakhulu yamandla amakhulu emishini kagesi.

Amadivayisi alawulwa ensimini adinga cishe akukho okokufaka kwamanje lapho uphumula. Kodwa-ke, phakathi nenqubo yokushintsha, i-capacitor yokufaka idinga ukushajwa futhi ikhishwe, okusadinga inani elithile lamandla okushayela. Lapho imvamisa yokushintsha iphakeme, amandla okushayela ayadingeka.

1.4 Ukuthuthukiswa kokusebenza okunamandla

Ngokungeziwe kuhlelo lokusebenza lwedivayisi ukucabangela i-voltage yedivayisi, yamanje, imvamisa, kodwa futhi kufanele ibe yingcweti ekusebenziseni indlela yokuvikela idivayisi, hhayi ukwenza idivayisi enguqukweni yesikhashana emonakalweni. Yebo i-thyristor iyinhlanganisela yama-bipolar transistors, ahlanganiswe namandla amakhulu ngenxa yendawo enkulu, ngakho amandla ayo e-dv/dt asengozini kakhulu. Ku-di/dt iphinde ibe nenkinga yesifunda yokuqhuba, ngakho futhi ibeka imikhawulo enzima impela.

Icala lamandla e-MOSFET lihluke kakhulu. Amandla ayo e-dv/dt kanye ne-di/dt ngokuvamile alinganiselwa ngokwamandla nge-nanosecond ngayinye (kunokuba nge-microsecond ngayinye). Kodwa naphezu kwalokhu, inemikhawulo yokusebenza enamandla. Lokhu kungaqondwa ngokuya ngesakhiwo esiyisisekelo se-MOSFET yamandla.

Isakhiwo se-MOSFET yamandla kanye nesekethe efanayo efanayo. Ngokungeziwe ku-capacitance cishe kuzo zonke izingxenye zedivayisi, kufanele kucatshangelwe ukuthi i-MOSFET ine-diode exhunywe ngokuhambisana. Ngokombono othile, kukhona ne-transistor ye-parasitic. (Njengoba i-IGBT nayo ine-thyristor eyisinanakazana). Lezi izinto ezibalulekile ocwaningweni lokuziphatha okuguquguqukayo kwama-MOSFET.

Okokuqala nje i-intrinsic diode exhunywe esakhiweni se-MOSFET inekhono elithile le-avalanche. Lokhu kuvame ukuvezwa ngokwamandla e-avalanche eyodwa kanye nekhono le-avalanche eliphindaphindayo. Uma i-reverse di/dt inkulu, i-diode ingaphansi kokushaya kwe-pulse okusheshayo, okunamandla okungena endaweni ye-avalanche futhi engase ilimaze idivayisi uma amandla ayo e-avalanche eseqile. Njenganoma iyiphi i-PN junction diode, ukuhlolisisa izici zayo eziguqukayo kuyinkimbinkimbi impela. Zihluke kakhulu emcabangweni olula we-PN junction oqhuba ubheke phambili futhi uvimbele ubheke emuva. Lapho i-current yehla ngokushesha, i-diode ilahlekelwa amandla ayo okuvimba ahlehlayo isikhathi esaziwa ngokuthi isikhathi sokuhlehla sokubuyisela. kukhona nesikhathi lapho i-PN junction idingeka ukuthi iqhube ngokushesha futhi ayibonisi ukumelana okuphansi kakhulu. Uma sekunomjovo oya phambili ku-diode ku-MOSFET yamandla, abathwali abambalwa abajovwe bangeza nobunkimbinkimbi be-MOSFET njengethuluzi le-multitronic.

Izimo zesikhashana zihlobene eduze nezimo zomugqa, futhi lesi sici kufanele sinakwe ngokwanele esicelweni. Kubalulekile ukuba nolwazi olujulile lwedivayisi ukuze kube lula ukuqonda nokuhlaziya izinkinga ezihambisanayo.