Muva nje, lapho amakhasimende amaningi eza kwa-Olukey ezobonisana ngama-MOSFET, azobuza umbuzo, indlela yokukhetha i-MOSFET efanelekile?Mayelana nalo mbuzo, u-Olukey uzowuphendula wonke umuntu.
Okokuqala, sidinga ukuqonda umgomo we-MOSFET.Imininingwane ye-MOSFET yethulwa ngokuningiliziwe esihlokweni esedlule esithi "Iyini i-MOS Field Effect Transistor".Uma ungakacaci, ungafunda ngakho kuqala.Kalula nje, i-MOSFET ingeyezingxenye ze-semiconductor elawulwa yi-Voltage inezinzuzo zokumelana nokufaka okuphezulu, umsindo ophansi, ukusetshenziswa kwamandla aphansi, ububanzi obuguquguqukayo, ukuhlanganiswa okulula, akukho ukwehlukana kwesibili, kanye nebanga elikhulu lokusebenza eliphephile.
Ngakho-ke, kufanele sikhethe kanjani okulungileI-MOSFET?
1. Nquma ukuthi uzosebenzisa i-N-channel noma i-P-channel MOSFET
Okokuqala, kufanele siqale sinqume ukuthi sisebenzise i-N-channel noma i-P-channel MOSFET, njengoba kukhonjisiwe ngezansi:
Njengoba kubonakala esibalweni esingenhla, kunomehluko osobala phakathi kwe-N-channel kanye ne-P-channel MOSFETs.Isibonelo, uma i-MOSFET imisiwe futhi umthwalo uxhunywe ku-voltage yegatsha, i-MOSFET yenza iswishi eseceleni enevoltage ephezulu.Ngalesi sikhathi, kufanele kusetshenziswe i-MOSFET yesiteshi se-N.Ngokuphambene, lapho i-MOSFET ixhunywe ebhasini futhi umthwalo uphansi, kusetshenziswa inkinobho yohlangothi oluphansi.Ama-MOSFET esiteshi se-P ngokuvamile asetshenziswa ku-topology ethile, okubuye kube ngenxa yokucatshangelwa kwe-voltage drive.
2. I-voltage eyengeziwe kanye namandla angeziwe e-MOSFET
(1).Nquma i-voltage eyengeziwe edingwa i-MOSFET
Okwesibili, sizophinde sinqume i-voltage eyengeziwe edingekayo ku-voltage drive, noma umthamo omkhulu we-voltage ongawemukela idivayisi.I-voltage eyengeziwe ye-MOSFET iba nkulu.Lokhu kusho ukuthi uma zinkulu izidingo ze-MOSFETVDS ezidinga ukukhethwa, kubaluleke kakhulu ukwenza izilinganiso ezihlukene nokukhetha ngokusekelwe ku-voltage ephezulu i-MOSFET engakwamukela.Vele, ngokujwayelekile, okokusebenza okuphathekayo kungu-20V, ugesi we-FPGA ungu-20~30V, kanti u-85~220VAC ungu-450~600V.I-MOSFET ekhiqizwe yi-WINSOK inokumelana namandla kagesi aqinile kanye nezinhlelo eziningi zokusebenza, futhi ithandwa iningi labasebenzisi.Uma unezidingo, sicela uxhumane nesevisi yamakhasimende eku-inthanethi.
(2) Nquma isikhathi esengeziwe esidingwa yi-MOSFET
Lapho izimo ze-voltage ezilinganisiwe nazo zikhethiwe, kuyadingeka ukucacisa okwamanje okulinganiselwe okudingwa yi-MOSFET.Lokho okubizwa ngokuthi i-current rated empeleni iyinani eliphezulu lamanje umthwalo we-MOS ongamelana nalo ngaphansi kwanoma yiziphi izimo.Ngokufanayo nesimo se-voltage, qiniseka ukuthi i-MOSFET oyikhethayo ingakwazi ukuphatha inani elithile lamanje lamanje, ngisho noma uhlelo lukhiqiza ama-spikes amanje.Izimo ezimbili zamanje okufanele zicatshangelwe amaphethini aqhubekayo nama-pulse spikes.Kumodi yokuqhuba eqhubekayo, i-MOSFET isesimweni esizinzile, lapho i-current iqhubeka nokugeleza kudivayisi.I-Pulse spike ibhekisela enanini elincane lokuhlinza (noma umthamo wamanje) ogeleza ocingweni.Uma inani eliphezulu lamanje endaweni selinqunyiwe, udinga kuphela ukukhetha ngokuqondile idivayisi engakwazi ukumelana nomthamo othile wamanje.
Ngemuva kokukhetha i-current eyengeziwe, ukusetshenziswa komqhubi kufanele kucatshangelwe.Ezimweni zangempela, i-MOSFET ayilona idivayisi yangempela ngoba amandla e-kinetic asetshenziswa phakathi nenqubo yokuqhuba ukushisa, okubizwa ngokuthi ukulahlekelwa kwe-conduction.Uma i-MOSFET "ivuliwe", isebenza njenge-resistor eguquguqukayo, enqunywa i-RDS(ON) yedivayisi futhi ishintsha kakhulu ngesilinganiso.Ukusetshenziswa kwamandla komshini kungabalwa nge-Iload2×RDS(ON).Njengoba ukumelana nokubuyisela kushintsha ngesilinganiso, ukusetshenziswa kwamandla kuzoshintsha ngokufanele.Uma iphezulu i-voltage VGS esetshenziswa ku-MOSFET, i-RDS(ON) izoba mancane;ngokuphambene, i-RDS(ON) izoba phezulu.Qaphela ukuthi ukumelana ne-RDS(ON) kuncipha kancane ngokwamanje.Izinguquko zeqembu ngalinye lamapharamitha kagesi we-RDS (ON) resistor zingatholakala kuthebula lokukhetha umkhiqizo womkhiqizi.
3. Thola izidingo zokupholisa ezidingwa uhlelo
Isimo esilandelayo okufanele sahlulelwe yizidingo zokukhipha ukushisa ezidingwa uhlelo.Kulokhu, izimo ezimbili ezifanayo zidinga ukucatshangelwa, okuyisimo esibi kakhulu nesimo sangempela.
Mayelana nokuchithwa kokushisa kwe-MOSFET,Olukeyibeka phambili isixazululo esimweni esibi kakhulu, ngoba umphumela othile udinga umkhawulo omkhudlwana womshwalense ukuze uqinisekise ukuthi uhlelo aluhluleki.Kukhona idatha yokulinganisa edinga ukunakwa eshidini ledatha le-MOSFET;izinga lokushisa lokuhlangana kwedivayisi lilingana nesilinganiso esiphezulu sesimo kanye nomkhiqizo wokumelana nokushisa kanye nokuchithwa kwamandla (i-junction lokushisa = isilinganiso esiphezulu sesimo + [ukumelana nokushisa × ukuchithwa kwamandla]).Ukuchithwa kwamandla okuphezulu kwesistimu kungaxazululwa ngokuya ngefomula ethile, efana ne-I2×RDS (ON) ngencazelo.Sesivele sibale inani eliphezulu lamanje elizodlula kudivayisi futhi singabala i-RDS (ON) ngaphansi kwezilinganiso ezihlukene.Ukwengeza, ukuchithwa kokushisa kwebhodi lesifunda kanye ne-MOSFET yayo kufanele kunakekelwe.
Ukuqhekeka kwe-avalanche kusho ukuthi i-voltage ehlehlayo engxenyeni ye-semi-superconducting idlula inani eliphakeme futhi yakha inkambu yakazibuthe enamandla ekhulisa amandla amanje engxenyeni.Ukwanda kosayizi we-chip kuzothuthukisa ikhono lokuvimbela ukuwa komoya futhi ekugcineni kuthuthukise ukuzinza komshini.Ngakho-ke, ukukhetha iphakheji elikhudlwana kungavimbela ngempumelelo ama-avalanche.
4. Nquma ukusebenza kokushintsha kwe-MOSFET
Isimo sokwahlulela sokugcina wukushintsha ukusebenza kwe-MOSFET.Kunezici eziningi ezithinta ukusebenza kokushintsha kwe-MOSFET.Okubaluleke kakhulu amapharamitha amathathu we-electrode-drain, i-electrode-source kanye ne-drain-source.I-capacitor ikhokhiswa njalo uma ishintsha, okusho ukuthi ukulahlekelwa kokushintsha kwenzeka ku-capacitor.Ngakho-ke, ijubane lokushintsha le-MOSFET lizokwehla, ngaleyo ndlela lithinte ukusebenza kahle kwedivayisi.Ngakho-ke, ohlelweni lokukhetha i-MOSFET, kuyadingeka futhi ukwahlulela nokubala ukulahlekelwa okuphelele kwedivayisi ngesikhathi senqubo yokushintsha.Kuyadingeka ukubala ukulahlekelwa ngesikhathi senqubo yokuvula (i-Eon) kanye nokulahlekelwa phakathi nenqubo yokuvala.(Ehle).Amandla aphelele weswishi ye-MOSFET angavezwa ngezibalo ezilandelayo: Psw = (Eon + Eoff) × imvamisa yokushintsha.Ukushajwa kwesango (Qgd) kunomthelela omkhulu ekushintsheni ukusebenza.
Ukufingqa, ukukhetha i-MOSFET efanelekile, isahlulelo esihambisanayo kufanele senziwe ngezici ezine: amandla kagesi engeziwe kanye namandla angeziwe e-N-channel MOSFET noma i-P-channel MOSFET, izidingo zokukhipha ukushisa kohlelo lwedivayisi kanye nokusebenza kokushintsha I-MOSFET.
Yilokho kuphela okwanamuhla kokuthi ungakhetha kanjani i-MOSFET efanele.Ngethemba ukuthi ingakusiza.
Isikhathi sokuthumela: Dec-12-2023
