Chifukwa chiyani kumakhala kovuta kuyesa kugwiritsa ntchito mphamvu za MOSFET ndikusintha ndi ma multimeter?

Za MOSFET yamphamvu kwambiri yakhala m'modzi mwa akatswiri omwe amafunitsitsa kukambirana za nkhaniyi, chifukwa chake tapanga chidziwitso chodziwika bwino komanso chodziwika bwino.MOSFET, ndikuyembekeza kuthandiza mainjiniya. Tiyeni tikambirane za MOSFET, gawo lofunika kwambiri!

Antistatic chitetezo

High-power MOSFET ndi insulated gate field effect chubu, chipata sichikhala chozungulira pano, kulowetsedwa kolowera ndikokwera kwambiri, ndikosavuta kuyambitsa kuphatikizika kwa static charge, zomwe zimapangitsa kuti voteji yayikulu ikhale chipata ndi gwero la wosanjikiza insulating pakati kuwonongeka.

Ambiri mwa kupanga MOSFETs oyambirira alibe miyeso odana ndi malo amodzi, kotero kusamala kwambiri m'manja ndi ntchito, makamaka ang'onoang'ono mphamvu MOSFETs, chifukwa mphamvu yaing'ono MOSFET athandizira capacitance ndi yaing'ono, pamene poyera magetsi malo amodzi amapanga voteji yapamwamba, yomwe imayamba chifukwa cha kuwonongeka kwa electrostatic.

Kupititsa patsogolo kwaposachedwa kwa MOSFET yamphamvu kwambiri ndi kusiyana kwakukulu, choyamba, chifukwa cha ntchito ya mphamvu yowonjezera yowonjezera imakhala yokulirapo, kotero kuti kukhudzana ndi magetsi osasunthika kumakhala ndi njira yolipiritsa, zomwe zimapangitsa kuti magetsi ang'onoang'ono awonongeke. za kuthekera kwa zing'onozing'ono, ndiyeno, tsopano MOSFET wamphamvu kwambiri pachipata chamkati ndi gwero la chipata ndi gwero la wolamulira wotetezedwa DZ, static ophatikizidwa mu chitetezo cha mtengo wa regulator diode voltage regulator Pansipa, tetezani bwino chipata ndi gwero la zosanjikiza zotchingira, mphamvu zosiyanasiyana, mitundu yosiyanasiyana ya MOSFET chitetezo chowongolera diode voltage regulator mtengo ndizosiyana.

Ngakhale njira zotetezera mkati za MOSFET zamphamvu kwambiri, tiyenera kugwira ntchito molingana ndi njira zogwirira ntchito zotsutsana ndi ma static, omwe ndi ogwira ntchito yosamalira oyenerera ayenera kukhala nawo.

Kuzindikira ndi kusintha

Pokonza ma TV ndi zida zamagetsi, adzakumana ndi kuwonongeka kwazinthu zosiyanasiyana,MOSFETilinso pakati pawo, momwe antchito athu osamalira amagwiritsira ntchito ma multimeter omwe amagwiritsidwa ntchito kuti adziwe zabwino ndi zoipa, zabwino ndi zoipa MOSFET. M'malo mwa MOSFET ngati palibe wopanga yemweyo ndi chitsanzo chomwecho, momwe mungasinthire vutoli.

1, mayeso amphamvu kwambiri a MOSFET:

Monga ambiri magetsi TV kukonza ogwira mu muyeso wa kristalo transistors kapena diode, zambiri ntchito multimeter wamba kudziwa zabwino ndi zoipa transistors kapena diode, ngakhale chiweruzo cha transistor kapena diode magawo magetsi sangathe kutsimikiziridwa, koma bola ngati njirayo ndi yolondola kutsimikizira kwa crystal transistors "zabwino" ndi "zoipa" kapena "zoipa" kuti zitsimikizidwe za crystal transistors. "Zoyipa" kapena palibe vuto. Mofananamo, MOSFET ingakhalenso

Kuyika ma multimeter kuti mudziwe "zabwino" ndi "zoyipa", kuchokera pakukonza wamba, zithanso kukwaniritsa zosowa.

Kuzindikira kuyenera kugwiritsa ntchito multimeter yamtundu wa pointer (mita ya digito siyoyenera kuyeza zida za semiconductor). Kwa mphamvu yamtundu wa MOSFET yosinthira machubu ndi njira yowonjezera ya N-channel, zopangidwa ndi opanga pafupifupi zonse zimagwiritsa ntchito mawonekedwe a phukusi la TO-220F (amatanthawuza magetsi osinthira mphamvu ya 50-200W ya chubu chosinthira kumunda) , ma elekitirodi atatu amakhalanso ogwirizana, ndiko kuti, atatu

Mapini pansi, chosindikizira choyang'ana mwiniwake, pini yakumanzere ya chipata, pini yoyesera yolondola ya gwero, pini yapakati ya kukhetsa.

(1) multimeter ndi kukonzekera kogwirizana:

Choyamba, pamaso muyeso ayenera kugwiritsa ntchito multimeter, makamaka ntchito ohm zida, kumvetsa ohm chipika adzakhala olondola ntchito ohm chipika kuyeza kristalo transistor ndi.MOSFET.

Ndi multimeter ohm chipika ohm pakati sikelo sangakhale lalikulu kwambiri, makamaka zosakwana 12 Ω (500-mtundu tebulo 12 Ω), kotero kuti mu R × 1 chipika akhoza kukhala yaikulu panopa, kwa PN mphambano ya kutsogolo. zizindikiro za chiweruzo ndi zolondola kwambiri. Multimeter R × 10K chipika batire mkati ndi bwino kuposa 9V, kotero kuti kuyeza PN mphambano inverse kutayikira panopa ndi yolondola, apo ayi kutayikira sangathe kuyeza.

Tsopano chifukwa cha kupita patsogolo kwa kupanga, kuwunika kwa fakitale, kuyezetsa kumakhala kovuta kwambiri, timaweruza bola ngati chigamulo cha MOSFET sichikudumphira, sichikudutsa dera lalifupi, kusazungulira mkati, kumatha kukulitsidwa panjira, njirayo ndi yosavuta kwambiri:

Kugwiritsa ntchito multimeter R × 10K chipika; R × 10K chipika batire mkati nthawi zambiri 9V kuphatikiza 1.5V kuti 10.5V voteji nthawi zambiri amaonedwa kuti zokwanira PN mphambano inversion kutayikira, cholembera chofiira cha multimeter ndi zoipa kuthekera (zogwirizana ndi zoipa terminal batire mkati), ndi Cholembera chakuda cha multimeter ndichothekera chabwino (cholumikizidwa ku terminal yabwino ya batire yamkati).

(2) Njira yoyesera:

Lumikizani cholembera chofiira ku gwero la MOSFET S; gwirizanitsani cholembera chakuda ndi kukhetsa kwa MOSFET D. Panthawiyi, chizindikiro cha singano chiyenera kukhala chopanda malire. Ngati pali chizindikiro cha ohmic, chosonyeza kuti chubu yomwe ikuyesedwa ili ndi vuto lotuluka, chubuchi sichingagwiritsidwe ntchito.

Sungani zomwe zili pamwambazi; panthawiyi ndi 100K ~ 200K resistor yolumikizidwa ndi chipata ndikukhetsa; panthawiyi singano iyenera kuwonetsa chiwerengero cha ohms chocheperako bwino, nthawi zambiri chikhoza kuwonetsedwa ku 0 ohms, nthawi ino ndi malipiro abwino kupyolera mu 100K resistor pa MOSFET kuchipata chipata, zomwe zimapangitsa kuti pakhale magetsi a chipata, chifukwa cha gawo lamagetsi lopangidwa ndi njira yoyendetsera kukhetsa ndi kutulutsa gwero, kotero kupotoka kwa singano ya multimeter, mbali yolowera ndi yayikulu (mlozera wa Ohm ndi small) kutsimikizira kuti ntchito yotulutsa ndi yabwino.

Kenako olumikizidwa ku resistor atachotsedwa, ndiye cholozera cha multimeter chiyenera kukhalabe MOSFET pa index sichinasinthe. Ngakhale resistor kuchotsa, koma chifukwa resistor pachipata mlandu ndi mlandu si kutha, chipata magetsi munda akupitiriza kukhala mkati conductive njira akadali anakhalabe, amene ndi makhalidwe a insulated chipata mtundu MOSFET.

Ngati resistor kuchotsa singano pang'onopang'ono kubwerera kukana mkulu kapena ngakhale kubwerera wopandamalire, kuganizira kuti anayeza chubu chipata kutayikira.

Panthawiyi ndi waya, wolumikizidwa ndi chipata ndi gwero la chubu choyesedwa, cholozera cha multimeter nthawi yomweyo chinabwerera ku infinity. Kulumikizana kwa waya kuti kuyeza MOSFET, kumasulidwa kwa chipata, gawo lamagetsi lamkati lizimiririka; conductive njira komanso kutha, kotero kuda ndi gwero pakati kukana ndi kukhala wopandamalire.

2, MOSFET yamphamvu kwambiri m'malo

Pakukonza ma TV ndi mitundu yonse ya zida zamagetsi, kukumana ndi kuwonongeka kwa chigawocho kuyenera kusinthidwa ndi mtundu womwewo wa zigawo. Komabe, nthawi zina zigawo zofanana sizili pa dzanja, m'pofunika kugwiritsa ntchito mitundu ina ya m'malo, kotero kuti tiyenera kuganizira mbali zonse za ntchito, magawo, miyeso, etc., monga TV mkati linanena bungwe chubu, monga bola ngati kuganizira voteji, panopa, mphamvu zambiri akhoza m'malo (mzere linanena bungwe chubu pafupifupi ofanana miyeso ya maonekedwe), ndipo mphamvu amakonda kukhala zazikulu ndi bwino.

Kwa MOSFET m'malo, ngakhale mfundo imeneyi, ndi bwino kuti prototype zabwino, makamaka, musati kutsata mphamvu kukhala yaikulu, chifukwa mphamvu ndi yaikulu; athandizira capacitance ndi lalikulu, anasintha ndi mabwalo chisangalalo sizimafanana chisangalalo cha mlandu panopa kuchepetsa resistor wa dera ulimi wothirira wa kukula kwa mtengo kukana ndi athandizira capacitance wa MOSFET zikugwirizana ndi kusankha kwa mphamvu yaikulu ngakhale mphamvu yaikulu, koma capacitance athandizira ndi lalikulu, ndi capacitance athandizira ndi lalikulu, ndi mphamvu si lalikulu.

Mphamvu yolowera ndi yayikulu, mayendedwe osangalatsa siabwino, zomwe zimapangitsa kuti MOSFET iyambike ndikuyimitsa ntchito. Imawonetsa kusinthidwa kwa mitundu yosiyanasiyana ya ma MOSFET, poganizira za kuthekera kwa gawoli.

Mwachitsanzo, pali 42 inchi LCD TV backlight high-voltage board kuwonongeka, pambuyo pofufuza mkati mkulu-mphamvu MOSFET kuwonongeka, chifukwa palibe chiwerengero chiwerengero cha m'malo, kusankha voteji, panopa, mphamvu si zochepa kuposa choloŵa m'malo choyambirira cha MOSFET, chotsatira chake ndi chubu chowunikira chakumbuyo chikuwoneka ngati chikugwedezeka mosalekeza (zovuta zoyambira), ndipo pamapeto pake zimasinthidwa ndi mtundu womwewo wa choyambirira kuti athetse vutoli.

Kuwonongeka kwa MOSFET yamphamvu kwambiri, m'malo mwa zigawo zake zotumphukira zagawo la perfusion kuyeneranso kusinthidwa, chifukwa kuwonongeka kwa MOSFET kumathanso kukhala magawo ozungulira a perfusion omwe amayamba chifukwa cha kuwonongeka kwa MOSFET. Ngakhale MOSFET yokhayo itawonongeka, pomwe MOSFET ikusweka, zigawo zozungulira za perfusion zimavulazidwa ndipo ziyenera kusinthidwa.

Monga momwe tili ndi mbuye wokonzekera bwino kwambiri pokonza magetsi a A3; bola ngati chubu chosinthira chikupezeka kuti chasweka, chimakhalanso kutsogolo kwa chubu chokokera cha 2SC3807 pamodzi ndi kusinthanso chifukwa chomwechi (ngakhale chubu cha 2SC3807, choyezedwa ndi multimeter ndichabwino).