Cov lus piav qhia ntxaws ntawm daim duab qhia kev ua haujlwm ntawm MOSFET | Kev soj ntsuam ntawm cov qauv sab hauv ntawm FET

MOSFET yog ib qho ntawm cov khoom tseem ceeb tshaj plaws hauv kev lag luam semiconductor. Hauv cov hluav taws xob hluav taws xob, MOSFET feem ntau yog siv rau hauv lub hwj chim amplifier circuits lossis hloov hluav taws xob circuits thiab tau siv dav. Hauv qab no,OLUKEYyuav muab cov lus piav qhia ntxaws ntxaws txog txoj hauv kev ua haujlwm ntawm MOSFET thiab txheeb xyuas cov qauv sab hauv ntawm MOSFET.

Dab tsi yogMOSFET

MOSFET, Hlau Oxide Semiconductor Filed Effect Transistor (MOSFET). Nws yog ib qho txiaj ntsig zoo ntawm transistor uas tuaj yeem siv dav hauv analog circuits thiab digital circuits. Raws li qhov sib txawv polarity ntawm nws "channel" (cov neeg nqa khoom ua haujlwm), nws tuaj yeem muab faib ua ob hom: "N-hom" thiab "P-hom", uas feem ntau hu ua NMOS thiab PMOS.

MOSFET txoj cai ua haujlwm

MOSFET tuaj yeem muab faib ua hom kev txhim kho thiab hom depletion raws li hom kev ua haujlwm. Hom kev txhim kho yog hais txog MOSFET thaum tsis muaj qhov tsis ncaj ncees lawm thiab tsis muaj conductive channel. Hom depletion yog hais txog MOSFET thaum tsis muaj qhov tsis ncaj ncees lawm. Ib tug conductive channel yuav tshwm sim.

Hauv kev siv tiag tiag, tsuas muaj N-channel txhim kho hom thiab P-channel txhim kho hom MOSFETs. Txij li thaum NMOSFETs muaj me me hauv xeev tsis kam thiab yooj yim rau kev tsim, NMOS muaj ntau dua PMOS hauv cov ntawv thov tiag tiag.

Txhim kho hom MOSFET

Muaj ob qhov rov qab-rau-rov qab PN junctions ntawm qhov ntws D thiab qhov chaw S ntawm kev txhim kho-hom MOSFET. Thaum lub rooj vag-qhov hluav taws xob VGS = 0, txawm hais tias qhov ntws-qhov hluav taws xob VDS ntxiv, yeej ib txwm muaj PN kev sib tshuam hauv lub xeev thim rov qab, thiab tsis muaj cov kab hluav taws xob nruab nrab ntawm qhov ntws thiab qhov chaw (tsis muaj tam sim no ntws. ). Yog li ntawd, cov dej ntws tam sim no ID = 0 nyob rau lub sijhawm no.

Thaum lub sij hawm no, yog hais tias ib tug pem hauv ntej voltage ntxiv ntawm lub rooj vag thiab qhov chaw. Ntawd yog, VGS> 0, tom qab ntawd ib qho hluav taws xob nrog lub rooj vag ua ke nrog P-hom silicon substrate yuav raug tsim nyob rau hauv SiO2 insulating txheej ntawm lub rooj vag electrode thiab silicon substrate. Vim tias cov oxide txheej yog insulating, qhov voltage VGS siv rau lub rooj vag tsis tuaj yeem tsim tam sim no. Lub capacitor yog tsim los ntawm ob sab ntawm cov oxide txheej, thiab VGS sib npaug Circuit Court tsub nqi no capacitor (capacitor). Thiab tsim ib qho hluav taws xob teb, raws li VGS maj mam nce, nyiam los ntawm qhov zoo voltage ntawm lub rooj vag. Ib tug loj tus naj npawb ntawm electrons sib sau nyob rau sab nraud ntawm lub capacitor (capacitor) thiab tsim N-hom conductive channel los ntawm ntws mus rau qhov chaw. Thaum VGS tshaj qhov tig-rau-voltage VT ntawm lub raj (feem ntau txog 2V), N-channel raj tsuas yog pib ua, tsim kom muaj tus ID ntws tam sim no. Peb hu lub rooj vag-qhov hluav taws xob thaum lub channel thawj zaug pib tsim qhov hluav taws xob tig. Feem ntau hais raws li VT.

Kev tswj qhov loj ntawm lub rooj vag voltage VGS hloov lub zog lossis qhov tsis muaj zog ntawm qhov hluav taws xob, thiab cov nyhuv ntawm kev tswj qhov loj ntawm qhov ntws tam sim no ID tuaj yeem ua tiav. Qhov no kuj yog ib qho tseem ceeb ntawm MOSFETs uas siv hluav taws xob teb los tswj tam sim no, yog li lawv tseem hu ua teb cov nyhuv transistors.

MOSFET Internal qauv

Ntawm P-hom silicon substrate nrog qhov tsis muaj impurity concentration, ob thaj tsam N + nrog rau siab impurity concentration yog ua, thiab ob lub electrodes raug rho tawm ntawm cov hlau txhuas los ua cov dej ntws d thiab qhov chaw s. Tom qab ntawd lub semiconductor nto yog them nrog ib tug nyias nyias silicon dioxide (SiO2) insulating txheej, thiab ib tug txhuas electrode yog ntsia rau ntawm insulating txheej ntawm lub ntws thiab qhov chaw los ua lub rooj vag g. Ib qho electrode B kuj tau kos tawm ntawm lub substrate, tsim N-channel txhim kho-hom MOSFET. Tib yam muaj tseeb rau kev tsim sab hauv ntawm P-channel txhim kho-hom MOSFETs.

N-channel MOSFET thiab P-channel MOSFET Circuit Court cim

Daim duab saum toj no qhia txog lub cim Circuit Court ntawm MOSFET. Hauv daim duab, D yog qhov ntws, S yog qhov chaw, G yog lub rooj vag, thiab xub xub hauv nruab nrab sawv cev rau lub substrate. Yog tias tus xub taw qhia sab hauv, nws qhia tau hais tias N-channel MOSFET, thiab yog tias tus xub taw qhia sab nraud, nws qhia tau tias P-channel MOSFET.

Dual N-channel MOSFET, dual P-channel MOSFET thiab N + P-channel MOSFET Circuit Court cim

Qhov tseeb, thaum lub sij hawm tsim cov txheej txheem MOSFET, lub substrate txuas nrog lub hauv paus ua ntej tawm hauv lub Hoobkas. Yog li ntawd, nyob rau hauv cov cai symbology, tus xub cim sawv cev rau lub substrate kuj yuav tsum tau txuas nrog rau qhov chaw kom paub qhov txawv qhov ntws thiab qhov chaw. Lub polarity ntawm qhov voltage siv los ntawm MOSFET zoo ib yam li peb cov tsoos transistor. N-channel zoo ib yam li NPN transistor. Lub qhov dej D yog txuas nrog qhov zoo electrode thiab qhov S yog txuas nrog qhov tsis zoo electrode. Thaum lub rooj vag G muaj qhov zoo ntawm qhov hluav taws xob, ib txoj kab hluav taws xob tau tsim thiab N-channel MOSFET pib ua haujlwm. Ib yam li ntawd, P-channel zoo ib yam li PNP transistor. Lub qhov dej D yog txuas nrog qhov tsis zoo electrode, lub hauv paus S txuas nrog rau qhov zoo electrode, thiab thaum lub rooj vag G muaj qhov tsis zoo voltage, ib tug conductive channel yog tsim thiab P-channel MOSFET pib ua hauj lwm.

MOSFET hloov txoj cai poob

Txawm hais tias nws yog NMOS lossis PMOS, muaj qhov ua haujlwm sab hauv tsis kam tsim tom qab nws qhib, yog li tam sim no yuav siv lub zog ntawm qhov kev tawm tsam sab hauv. Qhov no ntawm lub zog noj yog hu ua conduction noj. Xaiv ib tug MOSFET nrog ib tug me me conduction nyob rau hauv kuj yuav txo tau conduction noj. Tam sim no qhov kev tiv thaiv sab hauv ntawm MOSFETs qis yog feem ntau nyob ib ncig ntawm kaum ntawm milliohms, thiab tseem muaj ntau milliohms.

Thaum MOS qhib thiab kaw, nws yuav tsum tsis txhob hnov qab txog tam sim ntawd. Qhov hluav taws xob ntawm ob sab ntawm MOS yuav muaj qhov txo qis, thiab tam sim no ntws los ntawm nws yuav muaj qhov nce ntxiv. Lub sijhawm no, qhov poob ntawm MOSFET yog qhov khoom ntawm qhov hluav taws xob thiab qhov tam sim no, uas yog qhov kev hloov pauv. Feem ntau hais lus, kev hloov pauv qhov poob yog qhov loj dua qhov kev poob qis, thiab qhov nrawm dua qhov hloov pauv, qhov poob ntau dua.

Cov khoom ntawm voltage thiab tam sim no ntawm conduction yog loj heev, ua rau poob loj heev. Hloov kev poob tuaj yeem txo tau ob txoj hauv kev. Ib qho yog txo qis lub sijhawm hloov pauv, uas tuaj yeem txo qhov poob thaum txhua qhov tig-rau; lwm qhov yog txo qhov hloov zaus, uas tuaj yeem txo tus lej ntawm cov keyboards ib lub sijhawm.

Cov saum toj no yog cov lus piav qhia ntxaws ntxaws ntawm daim duab qhia kev ua haujlwm ntawm MOSFET thiab kev tsom xam ntawm cov qauv sab hauv ntawm MOSFET. Yog xav paub ntxiv txog MOSFET, txais tos sab laj OLUKEY los muab kev pabcuam MOSFET rau koj!