Beginner cov ntawm txhais tes xov tooj cua amateur: yuav ua li cas mus saib hauv lub FET

FETs - semiconductor pab kiag li lawm, nyob rau hauv uas cov kev tswj transients, raws li zoo raws li qhov ntau ntawm cov qhov tso zis tam sim no los hloov tus hluav taws xob field. Nws muaj ob hom ntawm cov pab kiag li lawm: nrog insulated rooj vag (nyob rau hauv lem muab faib mus rau hauv transistors nrog built-nyob rau hauv channel thiab induction channel) thiab tswj tau qhov kev hloov. FETs vim nws nws tus yam ntxwv yog lug siv nyob rau hauv hluav taws xob cov khoom: khoom siv fais fab, TV poob lawm, computers, thiab lwm yam

Thaum repairing xws khoom yeej txhua beginner xov tooj cua amateur ntsib nrog rau lo lus nug: yuav ua li cas mus saib hauv lub FET? Nyob rau hauv feem ntau tus neeg mob, pov thawj ntawm xws ntsiab tej zaum yuav ces yuav tsum thaum repairing pulsed khoom siv fais fab. Nyob rau hauv no tsab xov xwm peb piav qhia txog nyob rau hauv kom meej yuav ua li cas yuav ua rau nws kom raug.

Yuav ua li cas mus saib hauv lub FET ohmmeter

Ua ntej ntawm tag nrho cov, mus pib tshuaj ntsuam txog ntawm tus FET, nws yog tsim nyog los nrog nws "pinout", piv txwv nrog rau qhov chaw pins. Rau hnub tim, muaj ntau ntau yam sib txawv versions ntawm xws ntsiab, ntsig txog, qhov chaw ntawm lub electrodes muaj sib txawv. Koj muaj peev xwm feem ntau nrhiav tau semiconductor transistors nrog kos npe hu. Koj khij siv Latin ntawv G, D, S. Yog hais tias tus neeg kos npe yog tsis tam sim no, nws yog tsim nyog los siv siv phau ntawv.

Yog li ntawd, tsi tawm lub npav ntawm cov neeg, sib tham txog yuav ua li cas mus saib hauv lub FET. Cov kauj ruam tom ntej yog coj qhov tsim nyog kev ruaj ntseg ntsuas, vim hais tias lub teb pab kiag li lawm yog rhiab heev rau static hluav taws xob, thiab kom tsis txhob ua hauj lwm ntawm xws li ib lub caij, nws yog tsim nyog los npaj av. Yuav kom tau tawm lub sau zoo li qub xwb, feem ntau yog hnav nyob rau hauv lub dab teg anti-static av pluaj.

Peb yuav tsum tsis txhob hnov qab hais tias koj xav tau kom lub FETs nrog kaw cov lus xaus. Tshem static hluav taws xob, koj yuav npaj mus rau soj ntsuam xyuas cov txheej txheem. Qhov no yuav tsum tau ib tug yooj yim ohm 'meter'. Thaum serviceable caij ntawm tag nrho cov lus xaus ntawm tus kuj yuav tsum mus rau infinity, tab sis muaj ib co kev zam. Tam sim no peb saib yuav ua li cas tau kos ib lub teb nyhuv transistor ntawm n-hom.

Peb thov ib tug zoo tshuaj ntsuam ntaus ntawv mus rau lub rooj vag electrode (G), thiab qhov tsis zoo sojntsuam hu rau qhov chaw (S). Thaum no tus taw tes, nws pib mus rau nqi cov rooj vag capacitance thiab lub caij qhib. Thaum ntsuas cov kuj ntawm lub hauv paus thiab lub ntws (D) ohmmeter qhia ib co kuj muaj nqis. Cov ntau hom ntawm transistors, cov nqi no yog sib txawv. Yog hais tias lub luv luv-Circuit Court transistor terminals, cov kuj ntawm lub ntws thiab qhov chaw yuav rov qab yuav infinity. Yog hais tias nws tsis, nws txhais tau tias transistor yog faulty.

Yog hais tias koj hais li cas rau kos lub FET P-hom, cov lus teb yog yooj yim: rov hais dua cov saum toj no txoj kev tsuas hloov lub polarity. Peb yuav tsum tsis txhob hnov qab tias niaj hnub hwj chim FET ntawm qhov chaw thiab lub ntws muaj ib lub cev diode, ntsig txog, "prozvanivatsya" nws nyob rau hauv ib tug coj xwb.

Kos FET multimeter

Nyob rau hauv lub xub ntiag ntawm lub ntaus ntawv "DMM", koj yuav tau khij lub FET. Ua li no, peb las lub 'meter' rau "laaj" hom diodes thiab paub ib tug keeb ntawm cov teb nyob rau hauv lub saturation hom. Yog hais tias lub N-hom transistor, lub Rho tawm kev sojntsuam kov lub ntws thiab qhov zoo - shutter. Puas transistor nyob rau hauv xws li ib tug cov ntaub ntawv yog qhib. Peb hloov lub ntxiv kev sojntsuam tsis tau noj rho tawm, nyob rau hauv qhov chaw, thiab lub multimeter qhia ib co kuj muaj nqis. Tom qab ntawd tawm transistor: tsis muaj lifting lub stylus ntawm qhov chaw, rho tawm kov lub shutter thiab rov qab mus rau hauv qhov dej. Transistor blocks thiab kuj nyhav infinity.

Muaj ntau lub xov tooj cua amateurs yog hais tias: "Yuav ua li cas kuv mus saib lub FET, tsis vypaivaya" Tam sim ntawd teb hais tias txoj kev muaj yog tsis muaj ib puas feem pua. Ua li no, siv ib tug multimeter thaiv ntawm HFE, tab sis qhov no txoj kev feem ntau tsis, thiab koj yuav siv ib tug ntau lub sij hawm lub sij hawm.