Small voteji MOSFET kusankha ndi mbali yofunika kwambiri yaMOSFETkusankha si zabwino zingakhudze dzuwa ndi mtengo wa dera lonse, komanso adzabweretsa mavuto ambiri kwa akatswiri, mmene molondola kusankha MOSFET?
Kusankha N-channel kapena P-channel Gawo loyamba posankha chipangizo choyenera kupanga ndikusankha kugwiritsa ntchito MOSFET ya N-channel kapena P-channel. MOSFET imakhazikika ndipo katunduyo amalumikizidwa ndi thunthu lamagetsi. M'mbali yotsika yamagetsi, MOSFET ya N-channel iyenera kugwiritsidwa ntchito chifukwa choganizira mphamvu yamagetsi yomwe imafunika kuzimitsa kapena kuyatsa chipangizocho.
MOSFET ikalumikizidwa ndi basi ndipo katunduyo wakhazikika, chosinthira chamagetsi chapamwamba chiyenera kugwiritsidwa ntchito. P-channel MOSFETs nthawi zambiri amagwiritsidwa ntchito mu topology iyi, komanso pakuganizira za ma voltage drive. Dziwani mavoti apano. Sankhani mlingo wamakono wa MOSFET. Kutengera kapangidwe ka dera, mlingo wapanowu uyenera kukhala wokwera kwambiri womwe katunduyo ungathe kupirira nthawi zonse.
Mofanana ndi vuto la magetsi, wopanga ayenera kuonetsetsa kuti osankhidwaMOSFETimatha kupirira izi, ngakhale makinawo akupanga mafunde a spike. Milandu iwiri yomwe ikuyenera kuganiziridwa ndi nthawi yopitilira komanso ma pulse spikes. Mumayendedwe opitilira, MOSFET imakhala yokhazikika, pomwe pano ikudutsa mosalekeza pa chipangizocho.
Ma pulse spikes ndi pamene pali mafunde akulu (kapena ma spikes apano) akuyenda kudzera pa chipangizocho. Pamene mphamvu yapamwamba pansi pazimenezi yatsimikiziridwa, ndi nkhani yosankha mwachindunji chipangizo chomwe chingathe kupirira pakali pano. Kuzindikira Zofunikira za Thermal Kusankha MOSFET kumafunanso kuwerengera zomwe zimafunikira pakutentha kwadongosolo. Wopangayo ayenera kuganizira zochitika ziwiri zosiyana, zoyipitsitsa komanso zowona. Ndikofunikira kuti kuwerengera koyipa kwambiri kugwiritsidwe ntchito chifukwa kumapereka malire otetezeka ndikuwonetsetsa kuti dongosololi silingalephereke. Palinso miyeso ina yofunika kudziwa pa pepala la data la MOSFET; monga kukana matenthedwe pakati pa semiconductor mphambano ya chipangizo phukusi ndi chilengedwe, ndi pazipita mphambano kutentha. Posankha kusintha magwiridwe antchito, gawo lomaliza posankha MOSFET ndikusankha kusintha kwa magwiridwe antchito.MOSFET.
Pali magawo ambiri omwe amakhudza kusintha magwiridwe antchito, koma chofunikira kwambiri ndi chipata / kukhetsa, chipata / gwero, ndi kukhetsa / gwero lamphamvu. Ma capacitances awa amapangitsa kuti pakhale kuwonongeka kwa chipangizocho chifukwa amayenera kulipiritsidwa panthawi iliyonse yakusintha. Kuthamanga kwa MOSFET koteroko kumachepetsedwa ndipo mphamvu ya chipangizocho imachepa. Kuti muwerengere kuchuluka kwa kuwonongeka kwa chipangizo panthawi yosinthira, wopanga ayenera kuwerengera zotayika (Eon) ndi zotayika zozimitsa.
Pamene mtengo wa vGS uli wawung'ono, kutha kuyamwa ma electron sikuli kolimba, kutayikira - gwero pakati pa njira zomwe palibe conductive njira, kuwonjezeka kwa vGS, kulowetsedwa mu gawo la P gawo lakunja la ma electron pa kuwonjezeka, pamene vGS ifika mtengo wake, ma elekitironi omwe ali pachipata pafupi ndi mawonekedwe a P gawo lapansi amapanga gawo lochepa thupi la N-mtundu, ndipo ndi magawo awiri a N + olumikizidwa Pamene vGS ifika pamtengo wina, ma elekitironi awa pachipata pafupi ndi mawonekedwe a P gawo lapansi adzapanga N-mtundu woonda wosanjikiza, wolumikizidwa ku madera awiri a N +, mu kukhetsa - gwero limapanga njira yolumikizira yamtundu wa N, mtundu wake wowongolera ndi wosiyana ndi gawo lapansi la P, lomwe limapanga anti-mtundu wosanjikiza. vGS ndi yokulirapo, ntchito ya mawonekedwe a semiconductor yamphamvu yamagetsi, kuyamwa kwa ma electron kunja kwa gawo lapansi la P, momwe njira yopangira ma conductive imakulirakulira, kutsika kwa njirayo. Ndiko kuti, N-channel MOSFET mu vGS <VT, sangapange njira yoyendetsera, chubu ili m'malo opumira. Malingana ngati vGS ≥ VT, pokhapokha ngati njirayo ikupangidwira. Njira ikapangidwa, kukhetsa kwamagetsi kumapangidwa ndikuwonjezera voliyumu yakutsogolo vDS pakati pa drain - gwero.
Koma Vgs ikupitirizabe kuwonjezeka, tiyeni tinene kuti IRFPS40N60KVgs = 100V pamene Vds = 0 ndi Vds = 400V, zikhalidwe ziwiri, chubu ntchito kubweretsa zotsatira zotani, ngati kuwotchedwa, chifukwa ndi mkati limagwirira ndondomeko mmene Vgs kuonjezera kuchepetsa Ma Rds (pa) amachepetsa kutayika kwa kusintha, koma nthawi yomweyo adzawonjezera Qg, kotero kuti kutayika kwa kutembenuka kumakhala kokulirapo, kukhudza mphamvu ya MOSFET GS voliyumu ndi Vgg mpaka Cgs kulipira ndi kuwuka, idafika pamagetsi okonza Vth. , MOSFET kuyamba conductive; Kuwonjezeka kwaposachedwa kwa MOSFET DS, mphamvu ya Millier panthawiyi chifukwa cha kutulutsidwa kwa DS capacitance ndi kutulutsa, GS capacitance charger ilibe mphamvu zambiri; Qg = Cgs * Vgs, koma mtengowo upitilira kukula.
Magetsi a DS a MOSFET amatsikira ku voliyumu yofanana ndi Vgs, mphamvu ya Millier imakwera kwambiri, voteji yakunja imasiya kulipiritsa mphamvu ya Millier, voteji ya GS capacitance imakhalabe yosasinthika, voteji pa Millier capacitance imawonjezeka, pomwe voteji pa DS capacitance ikupitirizabe kuchepa; mphamvu ya DS ya MOSFET imatsika mpaka voteji pamayendedwe odzaza, mphamvu ya Millier imakhala yaying'ono Mphamvu ya DS ya MOSFET imatsikira ku voteji pa machulukitsidwe conduction, mphamvu ya Millier imakhala yaying'ono ndipo imaperekedwa pamodzi ndi mphamvu ya GS ndi galimoto yakunja. voteji, ndi voteji pa capacitance GS kukwera; njira zoyezera voteji ndi 3D01, 4D01, ndi Nissan's 3SK series.
Kutsimikiza kwa G-pole (chipata): gwiritsani ntchito zida za diode za multimeter. Ngati phazi ndi mapazi ena awiri pakati pa kutsika kwa magetsi abwino ndi oipa ndi aakulu kuposa 2V, ndiko kuti, kuwonetsera "1", phazi ili ndi chipata G. Kenako kusinthana cholembera kuti muyese mapazi ena onse, dontho lamagetsi ndilochepa nthawi imeneyo, cholembera chakuda chikugwirizana ndi D-pole (kukhetsa), cholembera chofiira chikugwirizana ndi S-pole (gwero).
Nthawi yotumiza: Apr-26-2024
