MOSFET yog dab tsi? Dab tsi yog qhov tseem ceeb parameter?

Thaum tsim ib lub zog hloov hluav taws xob lossis lub cev muaj zog tsav Circuit Court sivMOSFETs, yam xws li kev tiv thaiv, qhov siab tshaj plaws voltage, thiab qhov siab tshaj plaws tam sim no ntawm MOS feem ntau suav hais tias yog.

MOSFET cov raj yog ib hom FET uas tuaj yeem tsim los ua kev txhim kho lossis depletion hom, P-channel lossis N-channel rau tag nrho 4 hom. txhim kho NMOSFETs thiab txhim kho PMOSFETs feem ntau yog siv, thiab ob qho no feem ntau hais.

Ob qho no feem ntau siv yog NMOS. yog vim li cas yog hais tias cov conductive kuj yog me me thiab yooj yim rau manufacture. Yog li ntawd, NMOS feem ntau yog siv los hloov cov khoom siv hluav taws xob thiab kev siv lub cev muaj zog.

Hauv MOSFET, lub thyristor tau muab tso rau ntawm qhov ntws thiab qhov chaw, uas yog qhov tseem ceeb heev hauv kev tsav tsheb inductive xws li lub cev muaj zog, thiab tsuas yog muaj nyob rau hauv ib qho MOSFET nkaus xwb, feem ntau tsis yog nyob rau hauv ib qho kev sib xyaw ua ke.

Parasitic capacitance muaj nyob nruab nrab ntawm peb tus pins ntawm MOSFET, tsis yog peb xav tau, tab sis vim muaj kev txwv ntawm cov txheej txheem tsim khoom. Lub xub ntiag ntawm parasitic capacitance ua rau nws nyuaj dua thaum tsim lossis xaiv cov tsav tsheb, tab sis nws tsis tuaj yeem zam tau.

 

Lub ntsiab parameter ntawmMOSFET

1, qhib voltage VT

Qhib voltage (tseem hu ua qhov pib voltage): kom lub rooj vag voltage yuav tsum tau pib ua ib tug conductive channel ntawm qhov chaw S thiab ntws D; txheem N-channel MOSFET, VT yog hais txog 3 ~ 6V; los ntawm kev txhim kho cov txheej txheem, MOSFET VT tus nqi tuaj yeem txo qis rau 2 ~ 3V.

 

2, DC input tsis kam RGS

Qhov piv ntawm qhov hluav taws xob ntxiv ntawm lub rooj vag qhov rooj thiab lub rooj vag tam sim no Cov yam ntxwv no qee zaum qhia los ntawm lub rooj vag tam sim no ntws los ntawm lub rooj vag, MOSFET's RGS tuaj yeem yooj yim tshaj 1010Ω.

 

3. Dej qhov chaw tawg BVDS voltage.

Nyob rau hauv cov xwm txheej ntawm VGS = 0 (txhim kho), nyob rau hauv tus txheej txheem ntawm nce qhov ntws-qhov voltage, ID nce sharply thaum lub VDS yog hu ua lub ntws-qhov chaw tawg voltage BVDS, ID nce sharply vim ob yam: (1) avalanche kev tawg ntawm cov txheej txheem depletion nyob ze ntawm qhov ntws, (2) kev nkag mus ntawm cov kav dej thiab cov kav dej, qee qhov MOSFETs, uas muaj qhov luv luv trench ntev, ua kom cov VDS kom cov txheej ntws hauv cheeb tsam ntws tau nthuav dav mus rau thaj tsam qhov chaw, ua rau Channel ntev yog xoom, uas yog, tsim kom muaj qhov ntws tawm-qhov nkag, nkag mus, feem ntau ntawm cov neeg nqa khoom hauv cheeb tsam yuav raug cuam tshuam ncaj qha los ntawm hluav taws xob ntawm cov txheej txheem depletion mus rau thaj av ntws, uas ua rau muaj tus ID loj. .

 

4, lub rooj vag qhov chaw tawg voltage BVGS

Thaum lub rooj vag voltage nce, VGS thaum IG nce los ntawm xoom hu ua lub rooj vag qhov hluav taws xob tawg BVGS.

 

5,Tsawg zaus transconductance

Thaum VDS yog tus nqi ruaj khov, qhov sib piv ntawm microvariation ntawm qhov ntws tam sim no mus rau qhov microvariation ntawm lub qhov rooj qhov hluav taws xob uas ua rau qhov kev hloov pauv hu ua transconductance, uas qhia txog lub peev xwm ntawm lub qhov rooj qhov hluav taws xob los tswj cov dej ntws tam sim no, thiab yog ib qho kev hloov pauv. tseem ceeb parameter uas characterizes lub amplification muaj peev xwm ntawm lubMOSFET.

 

6, tiv thaiv RON

On-resistance RON qhia tau hais tias cov nyhuv ntawm VDS ntawm ID, yog qhov inverse ntawm txoj kab nqes ntawm txoj kab tangent ntawm cov yam ntxwv ntws ntawm ib qho chaw, hauv cheeb tsam saturation, ID yuav luag tsis hloov nrog VDS, RON yog qhov loj heev. tus nqi, feem ntau nyob rau hauv kaum ntawm kilo-Ohms mus rau pua pua ntawm kilo-Ohms, vim hais tias nyob rau hauv digital circuits, MOSFETs feem ntau ua hauj lwm nyob rau hauv lub xeev ntawm cov conductive VDS = 0, yog li ntawm no point, on-resistance RON yuav kwv yees los ntawm lub keeb kwm ntawm RON rau kwv yees, rau MOSFET, RON tus nqi nyob rau hauv ob peb puas ohms.

 

7, inter-polar capacitance

Interpolar capacitance muaj nyob nruab nrab ntawm peb lub electrodes: rooj vag qhov chaw capacitance CGS, rooj vag ntws capacitance CGD thiab ntws qhov chaw capacitance CDS-CGS thiab CGD yog hais txog 1 ~ 3pF, CDS yog hais txog 0.1 ~ 1pF.

 

8,Tsawg zaus suab nrov yam

Lub suab nrov yog tshwm sim los ntawm qhov tsis sib xws hauv kev txav ntawm cov cab kuj hauv cov kav dej. Vim tias nws muaj, tsis tu ncua voltage lossis tam sim no variations tshwm sim ntawm cov zis txawm tias tsis muaj teeb liab xa los ntawm lub amplifier. Kev ua haujlwm nrov nrov feem ntau yog hais txog lub suab nrov NF. Chav tsev yog decibel (dB). Qhov tsawg dua tus nqi, lub suab nrov tsawg lub raj tsim. Lub suab nrov tsawg yog qhov ntsuas suab nrov ntsuas hauv qhov tsawg zaus. Lub suab nrov ntawm lub raj ua haujlwm yog li ob peb dB, tsawg dua li ntawm bipolar triode.