Vim li cas nws ib txwm nyuaj rau kev sim siab zog MOSFET siv thiab hloov nrog multimeter?

Hais txog lub zog siab MOSFET tau yog ib tus kws tshaj lij engineers xav tham txog lub ntsiab lus, yog li peb tau teeb tsa qhov kev paub ntau yam thiab tsis tshua muaj txiaj ntsig ntawmMOSFET, Kuv vam tias yuav pab engineers. Wb tham txog MOSFET, ib feem tseem ceeb heev!

Anti-static tiv thaiv

High-power MOSFET yog ib qho insulated gate field effect tube, lub rooj vag yog tsis muaj ncaj qha tam sim no Circuit Court, input impedance siab heev, nws yog heev yooj yim mus ua static charge aggregation, uas ua rau ib tug high voltage yuav yog lub rooj vag thiab lub hauv paus ntawm cov txheej insulating ntawm qhov tawg.

Feem ntau ntawm cov khoom thaum ntxov ntawm MOSFETs tsis muaj kev tiv thaiv zoo li qub, yog li ceev faj heev hauv kev saib xyuas thiab daim ntawv thov, tshwj xeeb tshaj yog lub zog me me MOSFETs, vim lub zog me me MOSFET input capacitance kuj me me, thaum raug hluav taws xob zoo li qub ua rau lub zog me me. siab dua voltage, yooj yim los ntawm electrostatic tawg.

Kev txhim kho tsis ntev los no ntawm lub zog hluav taws xob MOSFET yog qhov sib txawv loj, ua ntej ntawm tag nrho cov, vim muaj kev ua haujlwm ntawm cov khoom siv hluav taws xob loj dua kuj tseem loj dua, yog li kev sib cuag nrog hluav taws xob zoo li qub muaj cov txheej txheem them nyiaj, ua rau lub zog me me, ua rau tawg. ntawm qhov muaj peev xwm me me, thiab tom qab ntawd dua, tam sim no lub zog siab MOSFET nyob rau hauv lub qhov rooj sab hauv thiab qhov chaw ntawm lub rooj vag thiab qhov chaw ntawm kev tiv thaiv regulator DZ, qhov zoo li qub. embedded nyob rau hauv kev tiv thaiv ntawm regulator diode voltage regulator tus nqi Hauv qab no, zoo tiv thaiv lub rooj vag thiab qhov chaw ntawm lub insulating txheej, txawv zog, txawv qauv ntawm MOSFET tiv thaiv regulator diode voltage regulator tus nqi yog txawv.

Txawm hais tias lub zog siab MOSFET kev tiv thaiv sab hauv, peb yuav tsum ua haujlwm raws li cov txheej txheem kev ua haujlwm zoo li qub, uas yog cov neeg ua haujlwm saib xyuas tsim nyog yuav tsum muaj.

Kev kuaj pom thiab hloov

Hauv kev kho cov TV thiab cov khoom siv hluav taws xob, yuav ntsib ntau yam kev puas tsuaj,MOSFETkuj yog ntawm lawv, uas yog li cas peb cov neeg ua haujlwm saib xyuas siv cov multimeter uas nquag siv los txiav txim siab qhov zoo thiab qhov tsis zoo, zoo thiab phem MOSFET. Hauv kev hloov ntawm MOSFET yog tias tsis muaj tib lub chaw tsim khoom thiab cov qauv qub, yuav hloov qhov teeb meem li cas.

1, high-power MOSFET xeem:

Raws li cov neeg ua haujlwm kho hluav taws xob hauv TV hauv kev ntsuas ntawm cov siv lead ua transistors lossis diodes, feem ntau yog siv cov multimeter zoo tib yam los txiav txim siab qhov zoo thiab qhov tsis zoo ntawm transistors lossis diodes, txawm hais tias qhov kev txiav txim ntawm cov transistor lossis diode hluav taws xob tsis tuaj yeem lees paub, tab sis ntev li ntev tau. cov txheej txheem yog qhov tseeb rau kev lees paub ntawm cov siv lead ua transistors "zoo" thiab "phem" lossis "phem" rau kev pom zoo ntawm crystal transistors. "Tsis zoo" los yog tsis muaj teeb meem. Ib yam li ntawd, MOSFET tuaj yeem ua tau

Siv lub multimeter los txiav txim nws "zoo" thiab "phem", los ntawm kev saib xyuas dav dav, kuj tuaj yeem ua tau raws li qhov xav tau.

Kev kuaj xyuas yuav tsum siv lub pointer hom multimeter (digital meter tsis haum rau ntsuas cov khoom siv hluav taws xob). Rau lub zog-hom MOSFET hloov raj yog N-channel txhim kho, cov khoom lag luam ntawm cov tuam txhab yuav luag txhua tus siv tib daim ntawv TO-220F pob ntawv (hais txog kev hloov hluav taws xob rau lub zog ntawm 50-200W ntawm thaj chaw cuam tshuam hloov raj) , peb electrode kev npaj kuj zoo ib yam, uas yog, peb

Pins down, luam qauv tig rau ntawm tus kheej, sab laug tus pin rau lub rooj vag, txoj cai kuaj tus pin rau qhov chaw, tus pin nruab nrab rau qhov ntws.

(1) Multimeter thiab lwm yam kev npaj:

Ua ntej ntawm tag nrho cov, ua ntej kev ntsuas yuav tsum tau siv lub multimeter, tshwj xeeb tshaj yog daim ntawv thov ntawm ohm iav, kom nkag siab txog lub ohm block yuav tsum yog daim ntawv thov ntawm ohm block los ntsuas cov siv lead ua transistor thiabMOSFET.

Nrog lub multimeter ohm thaiv ohm qhov chaw teev tsis tuaj yeem loj dhau, nyiam dua tsawg dua 12 Ω (500-hom rooj rau 12 Ω), yog li ntawd hauv R × 1 block tuaj yeem muaj qhov loj dua tam sim no, rau PN hlws ris ntawm pem hauv ntej. cov yam ntxwv ntawm kev txiav txim yog qhov tseeb dua. Multimeter R × 10K thaiv cov roj teeb sab hauv yog qhov zoo tshaj plaws ntau dua 9V, yog li hauv kev ntsuas PN junction inverse leakage tam sim no yog qhov tseeb dua, txwv tsis pub cov xau tsis tuaj yeem ntsuas.

Tam sim no vim yog kev nce qib ntawm cov txheej txheem tsim khoom, kev tshuaj ntsuam xyuas lub Hoobkas, kev sim nruj heev, peb feem ntau txiav txim siab ntev npaum li qhov kev txiav txim ntawm MOSFET tsis to, tsis tawg los ntawm luv luv Circuit Court, tsis muaj kev sib txuas, tuaj yeem ua tau. amplified ntawm txoj kev, txoj kev yog heev yooj yim:

Siv lub multimeter R × 10K thaiv; R × 10K thaiv cov roj teeb sab hauv feem ntau yog 9V ntxiv rau 1.5V rau 10.5V qhov hluav taws xob no feem ntau txiav txim siab kom txaus PN kev sib tshuam inversion to, tus cwj mem liab ntawm multimeter yog qhov tsis zoo (txuas mus rau qhov tsis zoo ntawm lub davhlau ya nyob twg ntawm lub roj teeb sab hauv), tus cwj mem dub ntawm lub multimeter yog qhov muaj peev xwm zoo (txuas mus rau lub davhlau ya nyob twg zoo ntawm lub roj teeb sab hauv).

(2) Cov txheej txheem xeem:

Txuas tus cwj mem liab mus rau qhov chaw ntawm MOSFET S; txuas tus cwj mem dub rau lub qhov dej ntws ntawm MOSFET D. Lub sijhawm no, lub koob qhia yuav tsum yog infinity. Yog tias muaj qhov ntsuas qhov ntsuas ohmic, qhia tias lub raj nyob rau hauv qhov kev sim muaj qhov tshwm sim, lub raj no siv tsis tau.

Tswj lub xeev saum toj no; lub sijhawm no nrog 100K ~ 200K resistor txuas nrog lub rooj vag thiab ntws; Lub sijhawm no tus koob yuav tsum qhia tus naj npawb ntawm ohms qhov me dua qhov zoo dua, feem ntau tuaj yeem qhia rau 0 ohms, lub sijhawm no nws yog tus nqi zoo los ntawm 100K resistor ntawm MOSFET rooj vag them, ua rau lub rooj vag hluav taws xob, vim Cov hluav taws xob hluav taws xob tsim los ntawm cov channel conductive uas ua rau cov dej ntws thiab qhov chaw conduction, yog li cov koob multimeter deflection, deflection lub kaum sab xis yog qhov loj (Ohm qhov ntsuas me me) rau ua pov thawj tias qhov kev tso tawm tau zoo.

Thiab tom qab ntawd txuas nrog lub resistor tshem tawm, ces lub multimeter pointer yuav tsum tseem yog MOSFET ntawm qhov ntsuas tseem tsis hloov. Txawm hais tias tus resistor tshem tawm, tab sis vim hais tias tus resistor mus rau lub rooj vag them los ntawm tus nqi tsis ploj mus, lub rooj vag hluav taws xob txuas ntxiv kom muaj cov kab hluav taws xob sab hauv tseem khaws cia, uas yog cov yam ntxwv ntawm lub rooj vag insulated hom MOSFET.

Yog hais tias tus resistor tshem tawm cov koob yuav maj mam thiab maj mam rov qab mus rau siab tiv thaiv los yog txawm rov qab mus rau infinity, xav txog tias qhov ntsuas lub qhov rooj ntawm lub raj xau.

Thaum lub sij hawm no nrog ib tug hlau, txuas nrog lub rooj vag thiab qhov chaw ntawm lub raj nyob rau hauv kev sim, lub multimeter tus pointer tam sim ntawd rov qab mus rau infinity. Kev sib txuas ntawm cov xaim kom ntsuas MOSFET, lub rooj vag nqi tso tawm, sab hauv hluav taws xob ploj; conductive channel kuj ploj mus, yog li qhov ntws thiab qhov chaw nruab nrab ntawm qhov tsis kam thiab ua tsis kawg.

2, siab zog MOSFET hloov

Hauv kev kho cov TV thiab txhua yam khoom siv hluav taws xob, ntsib kev puas tsuaj yuav tsum tau hloov nrog tib hom ntawm cov khoom. Txawm li cas los xij, qee zaum cov khoom qub tsis nyob ntawm tes, nws yog qhov yuav tsum tau siv lwm hom kev hloov pauv, yog li peb yuav tsum coj mus rau hauv tus account txhua yam ntawm kev ua tau zoo, tsis muaj, qhov ntev, thiab lwm yam, xws li TV hauv cov kab tso zis, xws li Ntev npaum li qhov kev xav ntawm qhov voltage, tam sim no, lub zog feem ntau tuaj yeem hloov pauv (kab cov khoom siv hluav taws xob yuav luag tib qhov ntev ntawm qhov pom), thiab lub zog yuav loj dua thiab zoo dua.

Rau kev hloov MOSFET, txawm hais tias kuj yog lub hauv paus ntsiab lus no, nws yog qhov zoo tshaj plaws los tsim qhov zoo tshaj plaws, tshwj xeeb, tsis txhob nrhiav lub zog kom loj dua, vim tias lub zog loj; input capacitance yog loj, hloov thiab excitation circuits tsis phim lub excitation ntawm tus nqi tam sim no limiting resistor ntawm irrigation Circuit Court ntawm qhov loj ntawm cov nqi kuj thiab cov input capacitance ntawm MOSFET muaj feem xyuam rau cov kev xaiv ntawm lub hwj chim loj txawm tias lub input capacitance. muaj peev xwm loj, tab sis lub input capacitance kuj loj, thiab input capacitance kuj loj, thiab lub hwj chim tsis loj.

Input capacitance kuj loj, lub excitation Circuit Court tsis zoo, uas nyob rau hauv lem yuav ua rau MOSFET rau thiab tawm kev ua tau zoo dua. Qhia txog kev hloov ntawm cov qauv sib txawv ntawm MOSFETs, coj mus rau hauv tus account lub input capacitance ntawm no parameter.

Piv txwv li, muaj 42-nti LCD TV backlight high-voltage board kev puas tsuaj, tom qab kuaj xyuas lub zog sab hauv MOSFET kev puas tsuaj, vim tias tsis muaj tus qauv hloov pauv, qhov kev xaiv ntawm qhov voltage, tam sim no, lub zog tsis tsawg dua. thawj MOSFET hloov, qhov tshwm sim yog lub backlight raj zoo nkaus li ib tug nruam flicker (pib teeb meem), thiab thaum kawg hloov nrog tib hom ntawm cov thawj los daws qhov teeb meem.

Pom kev puas tsuaj rau lub zog siab MOSFET, kev hloov pauv ntawm nws cov khoom siv peripheral ntawm lub perfusion Circuit Court kuj yuav tsum tau hloov, vim tias qhov kev puas tsuaj rau MOSFET kuj yog cov khoom tsis zoo perfusion Circuit Court los ntawm kev puas tsuaj rau MOSFET. Txawm hais tias MOSFET nws tus kheej puas lawm, lub sijhawm MOSFET tawg, lub perfusion Circuit Court Cheebtsam kuj raug mob thiab yuav tsum tau hloov.

Ib yam li peb muaj ntau tus kws kho mob ntse hauv kev kho A3 hloov hluav taws xob; ntev li ntev tau pom tias lub raj hloov pauv tau tawg, nws tseem yog lub hauv ntej ntawm 2SC3807 excitation raj ua ke nrog kev hloov ntawm tib lub laj thawj (txawm hais tias lub raj 2SC3807, ntsuas nrog lub multimeter yog qhov zoo).