Lub rooj vag capacitance, on-resistance thiab lwm yam tsis muaj MOSFETs

I. Rooj vag capacitance

Lub rooj vag capacitance feem ntau suav nrog input capacitance (Ciss), tso zis capacitance (Coss) thiab thim rov qab hloov capacitance (Crss, tseem hu ua Miller capacitance).

Input Capacitance (Ciss):

CEEB TOOM: Lub input capacitance yog tag nrho capacitance nruab nrab ntawm lub rooj vag thiab qhov chaw thiab ntws, thiab muaj lub rooj vag qhov chaw capacitance (Cgs) thiab lub rooj vag ntws capacitance (Cgd) txuas nyob rau hauv parallel, piv txwv li Ciss = Cgs + Cgd.

Muaj nuj nqi: Lub input capacitance cuam tshuam qhov hloov ceev ntawm MOSFET. Thaum lub input capacitance raug them rau qhov pib voltage, lub cuab yeej tuaj yeem qhib; tso tawm mus rau ib qho nqi, lub cuab yeej tuaj yeem muab tua. Yog li ntawd, kev tsav tsheb Circuit Court thiab Ciss muaj qhov cuam tshuam ncaj qha rau lub cuab yeej tig-on thiab tig-tawm ncua.

Output capacitance (Coss):

Txhais: Cov zis capacitance yog tag nrho cov capacitance nruab nrab ntawm qhov ntws thiab qhov chaw, thiab muaj cov dej ntws-qhov peev xwm (Cds) thiab lub rooj vag-drain capacitance (Cgd) nyob rau hauv parallel, piv txwv li Coss = Cds + Cgd.

Lub luag haujlwm: Hauv cov ntawv thov hloov pauv, Coss tseem ceeb heev vim tias nws yuav ua rau muaj kev cuam tshuam hauv Circuit Court.

Rov qab Transmission Capacitance (Crss):

Txhais: Qhov rov qab hloov pauv capacitance yog sib npaug rau lub rooj vag ntws capacitance (Cgd) thiab feem ntau hu ua Miller capacitance.

Lub luag hauj lwm: Qhov rov qab hloov pauv capacitance yog qhov tseem ceeb rau lub sijhawm nce thiab poob ntawm qhov hloov, thiab nws kuj cuam tshuam rau lub sijhawm tig-tawm ncua. Tus nqi capacitance txo qis raws li qhov ntws-qhov voltage nce.

II. On-resistance (Rds(on))

Lus Txhais: On-resistance yog qhov kev tiv thaiv ntawm qhov chaw thiab ntws ntawm MOSFET nyob rau hauv lub xeev nyob rau hauv tej yam kev mob (xws li, tshwj xeeb leakage tam sim no, rooj vag voltage, thiab kub).

Cov yam ntxwv cuam tshuam: On-resistance tsis yog tus nqi ruaj khov, nws cuam tshuam los ntawm qhov kub thiab txias, qhov kub siab dua, qhov ntau dua Rds(on). Tsis tas li ntawd, qhov siab dua qhov kev tiv thaiv hluav taws xob, qhov tuab ntawm cov qauv sab hauv ntawm MOSFET, qhov siab dua qhov sib xws ntawm kev ua haujlwm.

Qhov tseem ceeb: Thaum tsim cov khoom siv hluav taws xob hloov hluav taws xob lossis tsav tsheb, nws yuav tsum xav txog qhov kev tawm tsam ntawm MOSFET, vim tias tam sim no ntws los ntawm MOSFET yuav siv lub zog ntawm qhov kev tawm tsam no, thiab qhov no ntawm lub zog siv tau hu ua on- tsis kam poob. Xaiv ib qho MOSFET uas tsis tshua muaj kev tiv thaiv tuaj yeem txo qhov tsis kam tiv thaiv.

Thib peb, lwm yam tsis tseem ceeb

Ntxiv nrog rau lub rooj vag capacitance thiab on-resistance, MOSFET muaj qee qhov tseem ceeb xws li:

V(BR)DSS (Drain Source Breakdown Voltage):Lub qhov dej ntws tawm qhov hluav taws xob uas tam sim no ntws los ntawm qhov ntws mus txog tus nqi tshwj xeeb ntawm qhov kub thiab txias nrog lub rooj vag qhov chaw luv. Tshaj qhov nqi no, lub raj yuav puas.

VGS (th) (Threshold Voltage):Lub rooj vag voltage yuav tsum tau ua rau ib tug conducting channel pib tsim ntawm qhov chaw thiab ntws. Rau cov qauv N-channel MOSFETs, VT yog li 3 txog 6V.

ID (Maximum Continuous Drain Current):Qhov siab tshaj plaws nruam DC tam sim no uas tuaj yeem tso cai los ntawm nti ntawm qhov siab tshaj plaws ntsuas qhov ntsuas kub.

IDM (Maximum Pulsed Drain Tam Sim No):Qhia txog qib ntawm cov khoom siv tam sim no uas lub cuab yeej siv tau, nrog rau cov khoom siv hluav taws xob tau siab dua li DC tam sim no txuas ntxiv.

PD (qhov siab tshaj plaws lub zog dissipation):lub cuab yeej tuaj yeem dissipate qhov siab tshaj plaws siv hluav taws xob.

Nyob rau hauv cov ntsiab lus, lub rooj vag capacitance, on-resistance thiab lwm yam parameters ntawm ib tug MOSFET yog ib qho tseem ceeb rau nws cov kev ua tau zoo thiab daim ntawv thov, thiab yuav tsum tau xaiv thiab tsim raws li ib tug tshwj xeeb daim ntawv thov scenarios thiab yuav tsum tau.