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LTspice
变压器仿真的简单步骤：
为每个变压器绕组绘制一个电感器
采用一个互感(K)描述语句通过一条SPICE指令对其实施耦合：
K1L1L21
K语句的最后一项phedintheMOSFETdatasheetasCrss.
Thecapacitanceof
acapacitor
is
inversely
,distance
betweenthegateandtheconductingchannelofthedrainisequaltothethicknessofthe
insulatinggateoxidelayer(whichissmall)
theMOSFETisturnedoff,thegatedrainregionislarge,makingthegatedraincapacitance
.
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,
LTspiceassumesitisconstant.
Isistheparasiticbodydiodesaturationcurrent.
Rbistheseriesresistanceofthebodydiode.
TheFairchildFDS6680AMOSFETisdefinedinLTspicebytheline
.modelFDS6680AVDMOS(Rg=3Rd=5mRs=1mVto=Kp=63Cgdmax=2nCgdmin=1nCgs=Cjo=1nIs=Rb=6m
mfg=FairchildVds=30Ron=15mQg=27n)
Note:thecharacteristicsVds,
addedtoaidtheusertocompareMOSFETs.
ThereforeanexampletemplateMOSFETmodelis
.modelXXXXVDMOS(Rg=Rd=5Rs=1Vto=Kp=Cgdmax=Cgdmin=Cgs=Cjo=Is=Rb=)
Wearenowgoing toconstruct aMOSFETmodelfor theSUM75N06andSUM110N04lowONresistance
MOSFETsfromVishay
.modelSUM75N06-09LVDMOS(Rg=Rd=0mRs=25mVto=Kp=75Cgdmax=Cgdmin=150pCgs=2nCjo=Is=1pRb=0)
.modelSUM110N04VDMOS(Rg=R