********************************************************************************
* UnitedSiC G3 1700V-400mohm SiC JFET Spice Circuit Model v3.1
* Copyright 2021 United Silicon Carbide, Inc.
* This is a PRELIMINARY Spice Model of UF3N170400B7S
*
*
* The model does not include all possible conditions and effects, 
* in particular it doesn't include: 
*	Self heating
*	leakage current in blocking state
*	Drain to source breakdown is notional only
*
********************************************************************************

*** UF3N170400B7S ***
.subckt UF3N170400B7S nd ng ns nss
*#ASSOC Category="N-Channel JFET" Symbol=njfet
Ld	nd	nd1		3n
Ljg	ng	ng1		10n
Ls	ns	ns1		2n
xj1	nd1	ng1		ns1	jfet_G3_1700V_Ron params: Ron=400m Rgon=6 Rgoff=6
Lss nss ns1 	10n
.ends

******************* 1700V JFETs ***********************
.subckt jfet_G3_1700V_Ron d g s params: Ron=0 Rgon=0 Rgoff=0
.param Ron1={Ron}
.param Rgon1={Rgon}
.param Rgoff1={Rgoff}
.param a= {400m / {Ron}}
X1 di gi s jfet_G3_1700V params: ascale={a}
XCgs gi s Cgs_1700V params: acgs={a}
XCgd gi di Cgd_1700V params: acgd={a}
Rd d di Rtemp {320m/{a}}
.MODEL Rtemp RES (TC1=3.425e-3, TC2=4.292e-5)
GRg g gi value={if(v(g,gi)>0,v(g,gi)/{Rgon1},v(g,gi)/{Rgoff1})}
.ends

*********** Shared Subcircuit for 1700V JFETs *********
.subckt jfet_G3_1700V d g s Params: ascale=0

.param Fc1=0.5
.param Pb1=3.25
.param M1=0.5
.param Vd0=1360
.param gos={1.229e-3*{ascale}}
.param gfs={9.39*{ascale}}
.param f=1.4
.param vth=-9

.param cgs1=2.1e-10
.param cgd1=6.0e-12

.param bt={({f}*{gfs}+2*{gos}*{Vd0}/{vth})/2/(-{vth})}
.param lamd={1*{gos}/{bt}/{vth}/{vth}}
.param cgs0={pwr((1+20/{Pb1}),{M1})*{cgs1}}
.param cgd0={pwr((1+{Vd0}/{Pb1}),{M1})*{cgd1}}


J1 d g s jfet_1700
Dgs g s Dgs_iv 
Dgd g d Dgd_iv
Rgs  g s 1Meg
Rgd  g  d 10Meg

.MODEL jfet_1700 NJF(
+ Beta={{bt}} BetaTce=0 Vto={vth} VtoTc=0  lambda={lamd}
+ Is=1e-60 
+ Cgs={{cgs0}*{ascale}} Cgd={{cgd0}*{ascale}} Fc={Fc1} Pb={Pb1}
+ M={M1})

.MODEL Dgs_iv D (CJO=0 BV=40 IS=1e-50 ISR=1e-50 Eg=3.5 Rs=0)
.MODEL Dgd_iv D (CJO=0 BV=2150 IS=1e-50 ISR=1e-50 Rs={50.8m/{ascale}})

.ends 

* Cgs network	
.subckt Cgs_1700V g s params: acgs=0
.param c0=1n
.param vsgmin=-2
.param vsgmax=15
.param a1={0.18n*{acgs}}
.param b1=1 
.func Qgs1(u) {- {a1} / {b1} *(exp(- {b1} *u)-1)}  

.param a2={0.15n*{acgs}}
.param b2=0.5
.param c2=9.8

.func Qgs2(u) 
+	{if(abs(u)<{vsgmax},
+	{a2}*u + {a2}*(-{b2})*log(cosh((u-{c2})/-{b2}))
+	-{a2}*(-{b2})*log(cosh(-{c2}/-{b2})), 
+	{a2}*{vsgmax} + {a2}*(-{b2})*log(cosh(({vsgmax}-{c2})/-{b2}))
+	-{a2}*(-{b2})*log(cosh(-{c2}/-{b2})))} 

E1 s m1 value={v(s,g)-Qgs1(limit(v(s,g),-{vsgmax},{vsgmax}))/{c0}}
C01 m1 g {c0}
E2 s m2 value={v(s,g)-Qgs2(limit(v(s,g),-{vsgmax},{vsgmax}))/{c0}}
C02 m2 g {c0}

.ends 

* Cgd network
.subckt Cgd_1700V g d params:acgd=0

.param c0=1n

.param a1={0.05n*{acgd}}
.param b1=0.1
.param c1=17.6
.param vdgmax1=30
.func Qgd1(u) 
+	{if(abs(u)<{vdgmax1},
+	{a1}*u + {a1}*(-{b1})*log(cosh((u-{c1})/-{b1}))
+	-{a1}*(-{b1})*log(cosh(-{c1}/-{b1})), 
+	{a1}*{vdgmax1} + {a1}*(-{b1})*log(cosh(({vdgmax1}-{c1})/-{b1}))
+	-{a1}*(-{b1})*log(cosh(-{c1}/-{b1})))} 

.param a2={0*{acgd}}
.param b2=0.5
.param c2=9.5
.param vdgmax2=15

.func Qgd2(u) 
+	{if(abs(u)<{vdgmax2},
+	(-1)*({a2}*u + {a2}*(-{b2})*log(cosh((u-{c2})/-{b2}))
+	-{a2}*(-{b2})*log(cosh(-{c2}/-{b2}))), 
+	(-1)*({a2}*{vdgmax2} + {a2}*(-{b2})*log(cosh(({vdgmax2}-{c2})/-{b2}))
+	-{a2}*(-{b2})*log(cosh(-{c2}/-{b2}))))}



E1 d m1 value={v(d,g)-Qgd1(limit(v(d,g),-{vdgmax1},+{vdgmax1}))/{c0}}
C01 m1 g {c0}
*E2 d m2 value={v(d,g)-Qgd2(limit(v(d,g),-{vdgmax2},+{vdgmax2}))/{c0}}
*C02 m2 g {c0}

.ends 
*** End of File ***