HFE txhais li cas ntawm multimeter?
HFE teeb tsa ntawm lub multimeter ntsuas qhov tam sim no amplification yam ntawm lub transistor. Hom 'meter' no muaj lub qhov (socket) rau ntsuas qhov transistor. Qib hFE feem ntau yog siv los ntsuas tus nqi magnification. Ua ntej ntsuas, koj yuav tsum xub txiav txim siab seb lub transistor yog PNP lossis NPN hom, thiab txiav txim siab qhov polarity ntawm txhua tus pin.
Yuav siv li cas: Thaum ntsuas, ntxig lub triode rau hauv qhov sib thooj polarity jack, thiab koj tuaj yeem nyeem qhov tam sim no amplification yam ntawm triode.
Cov ntaub ntawv txuas ntxiv:
Lub 'meter' taub hau ntawm lub multimeter yog ib qho rhiab ammeter. Lub dial ntawm lub taub hau saib yog luam tawm nrog ntau yam cim, nplai thiab tus lej muaj nuj nqis. Lub cim AV-Ω qhia tias qhov ntsuas no yog ib lub ntsuas ntsuas uas tuaj yeem ntsuas tam sim no, qhov hluav taws xob thiab tsis kam.
Muaj ntau cov kab scale luam tawm ntawm lub dial. Ib qho cim nrog "Ω" nyob rau sab xis kawg yog cov kab tsis sib haum. Txoj cai kawg yog xoom thiab sab laug kawg yog ∞. Qhov ntsuas tus nqi faib tsis sib npaug. Lub cim "-" lossis "DC" sawv cev ncaj qha tam sim no, "~" lossis "AC" sawv cev rau qhov hloov pauv tam sim no, thiab "~" sawv cev rau cov kab sib faib los ntawm AC thiab DC. Ob peb kab ntawm tus lej nyob rau hauv kab kab yog qhov ntsuas qhov tseem ceeb sib raug rau qhov sib txawv zog ntawm tus xaiv hloov.
Lub hauv paus ntsiab lus ntawm kev ua haujlwm ntawm multimeter:
Lub hauv paus ntsiab lus ntawm multimeter yog siv lub rhiab magnetoelectric DC ammeter (microampere) ua lub taub hau meter. Thaum ib tug me me tam sim no hla lub 'meter', yuav muaj ib tug qhia tam sim no. Txawm li cas los xij, lub taub hau ' meter ' tsis tuaj yeem dhau qhov tam sim no loj, yog li qee qhov kev tiv thaiv yuav tsum tau txuas nrog rau kev sib txuas lossis series nrog lub taub hau 'meter' kom shunt lossis txo qhov hluav taws xob, txhawm rau ntsuas qhov tam sim no, qhov hluav taws xob thiab kev tiv thaiv hauv Circuit Court.
Hfe, PNP thiab NPN ntawm multimeter txhais li cas?
HFE yog lub npe luv ntawm triode DC tam sim no amplification yam, uas yog tam sim no amplification yam ntawm lub triode; PNP thiab NPN sawv cev rau ob hom triodes.
When the triode is on, IE=(amplification +1)*IB has nothing to do with ICB. When ICB=0 and ICB>0, there may be a problem with the triode, so when the triode is working normally, whether it is working in the amplification zone or the saturation zone ICB =0. When UEB>{{0}}.7V (silicon) (germanium 0.2V) thiab RC/RB
Qhov sib txawv ntawm PNP transistor thiab NPN transistor yog tias cov lus qhia ntawm ob lub PN junctions tsis sib haum.
PNP yog ib hom cathode, uas yog, N hlws ris ntawm ob lub PN junctions yog kev cob cog rua raws li lub hauv paus, thiab lwm yam ob P junctions yog siv los ua tus collector thiab emitter feem; lub triode yog cim nrog ib tug xub taw rau sab hauv hauv daim duab kos duab. NPN yog qhov opposite.
