Multimeter - Xaiv Semiconductor Transistors
Kev xaiv ntawm transistors yuav tsum xub ua raws li cov kev cai ntawm cov khoom siv thiab circuits, thiab thib ob, ua raws li txoj cai ntawm kev lag luam. Nyob ntawm daim ntawv thov, feem ntau yuav tsum tau xav txog: kev khiav hauj lwm zaus, cov khoom siv tam sim no, lub zog dissipated, tam sim no amplification yam, rov qab tawg voltage, stability thiab saturation voltage poob, thiab lwm yam. Cov yam ntxwv no muaj kev sib raug zoo ntawm kev sib raug zoo. Thaum lub sijhawm xaiv tsa thiab kev tswj hwm, peb yuav tsum tuav cov kev tsis sib haum xeeb tseem ceeb thiab coj mus rau hauv tus account thib ob yam.
Cov yam ntxwv zaus fT ntawm cov raj qis feem ntau yog qis dua 2.5MHz, thaum lub fT ntawm cov raj muaj ntau zaus ntawm kaum ntawm MHz mus rau ntau pua MHz lossis ntau dua. Thaum xaiv tswj, fT yuav tsum yog 3 mus rau 10 zaus ntawm kev khiav hauj lwm zaus. Raws li txoj cai, cov raj muaj ntau zaus tuaj yeem hloov cov raj qis, tab sis lub hwj chim ntawm cov raj muaj zog feem ntau kuj me me thiab qhov dynamic ntau yog nqaim. Ua tib zoo saib xyuas cov xwm txheej fais fab thaum hloov.
Feem ntau, peb cia siab tias yuav tsum loj dua, tab sis qhov loj dua tsis yog ib txwm zoo dua. Yog tias siab dhau lawm, nws yuav yooj yim ua rau nws tus kheej zoo siab oscillation, tsis txhob hais tias feem ntau cov hlab nrog siab tsis ruaj khov thiab cuam tshuam los ntawm qhov kub thiab txias. Feem ntau, tus nqi yog nyob nruab nrab ntawm 40 thiab 100, tab sis rau cov raj uas tsis tshua muaj suab nrov thiab tus nqi siab (xws li 1815, 9011 ~ 9015, thiab lwm yam), qhov kub thiab txias stability tseem zoo thaum tus nqi nce mus txog ntau pua. Tsis tas li ntawd, rau tag nrho cov Circuit Court, yuav tsum tau xaiv los ntawm kev sib koom tes ntawm txhua theem. Piv txwv li, yog tias theem pem hauv ntej siv lub raj beta siab, theem tom qab tuaj yeem siv lub raj qis beta; hloov pauv, yog tias theem pem hauv ntej siv lub raj beta qis, theem tom qab tuaj yeem siv lub raj beta siab.
Lub collector-emitter reverse breakdown voltage UCEO yuav tsum tau xaiv kom siab tshaj qhov voltage mov. Qhov me dua qhov nkag mus tam sim no, qhov zoo dua qhov kev ruaj ntseg tiv thaiv kub. Qhov kev ruaj ntseg ntawm cov raj zoo tib yam silicon zoo dua li cov raj germanium, tab sis qhov saturation voltage poob ntawm cov raj silicon zoo tib yam yog loj dua li ntawm germanium hlab, uas yuav cuam tshuam rau kev ua tau zoo ntawm cov hluav taws xob hauv ib co circuits. Nws yuav tsum raug xaiv raws li cov xwm txheej tshwj xeeb ntawm Circuit Court thiab kev noj ntawm lub transistor. Thaum dissipating zog, ib tug tej yam paj yuav tsum tau sab laug raws li cov kev cai ntawm txawv circuits.
Rau cov transistors siv nyob rau hauv circuits xws li high-frequency amplification, intermediate-frequency amplification, thiab oscillators, transistors nrog cov yam ntxwv siab zaus fT thiab me me inter-electrode capacitance yuav tsum tau xaiv los xyuas kom meej lub zog nce thiab stability ntawm high frequencies.
