* SPICE netlist
M1 out1 gate1 0 0 IPB035N08N3 RthetaJA=62 Tambient={t_amb}
R1 vin1 out1 5
V1 vin1 0 100
R2 gate1 vpulse1 50
V2 vpulse1 0 10
Rjc1 case1 junction1 1
Rca1 ambient1 case1 61
Rcsa1 ambient1 N001 20
VTa1 ambient1 0 {t_amb}
BPd1 0 junction1 I=V(out1)*Id(M1)+V(gate1)*Ig(M1)
M2 out2 gate2 0 0 IPB035N08N3 RthetaJA=62 Tambient={t_amb}
R3 vin2 out2 5
V3 vin2 0 100
R4 gate2 vpulse2 50
V4 vpulse2 0 10
Rjc2 case2 junction2 1
Rca2 ambient2 case2 61
Rcsa2 ambient2 case2 20
VTa2 ambient2 0 {t_amb}
BPd2 0 junction2 I=V(out2)*Id(M2)+V(gate2)*Ig(M2)
XU1 tc#m2 NC_01 NC_02 aluminum Rtheta=20 Tambient=25 Area_Contact_mm2=100 Volume_mm3=1000 ;pnba Tc)Tinterface)Tfin
.param t_amb=25
.options SOAaccounting=1 ;turns on SOA accounting for MOSFETs that include thermal data
+ temp 25
.tran 0 200 0 1

* LTspice schematic (.asc)
Version 4
SHEET 1 1600 928
WIRE -544 -464 -640 -464
WIRE -416 -464 -544 -464
WIRE 240 -464 144 -464
WIRE 368 -464 240 -464
WIRE -640 -432 -640 -464
WIRE -416 -432 -416 -464
WIRE 144 -432 144 -464
WIRE 368 -432 368 -464
WIRE 544 -368 528 -368
WIRE -640 -320 -640 -352
WIRE -416 -320 -416 -352
WIRE -384 -320 -416 -320
WIRE -352 -320 -384 -320
WIRE 144 -320 144 -352
WIRE 368 -320 368 -352
WIRE 400 -320 368 -320
WIRE 432 -320 400 -320
WIRE -416 -288 -416 -320
WIRE 368 -288 368 -320
WIRE -688 -208 -704 -208
WIRE -640 -208 -688 -208
WIRE -512 -208 -560 -208
WIRE -464 -208 -512 -208
WIRE 96 -208 80 -208
WIRE 144 -208 96 -208
WIRE 272 -208 224 -208
WIRE 320 -208 272 -208
WIRE -704 -192 -704 -208
WIRE 80 -192 80 -208
WIRE -416 -160 -416 -192
WIRE 368 -160 368 -192
WIRE -704 -96 -704 -112
WIRE 80 -96 80 -112
WIRE -688 64 -704 64
WIRE -640 64 -688 64
WIRE -512 64 -560 64
WIRE -464 64 -512 64
WIRE -336 64 -384 64
WIRE -272 64 -336 64
WIRE -240 64 -272 64
WIRE 144 64 128 64
WIRE 192 64 144 64
WIRE 320 64 272 64
WIRE 368 64 320 64
WIRE 496 64 448 64
WIRE 560 64 496 64
WIRE 592 64 560 64
WIRE -704 96 -704 64
WIRE -240 96 -240 64
WIRE 128 96 128 64
WIRE 592 96 592 64
WIRE -336 144 -336 64
WIRE 320 144 320 64
WIRE 496 144 496 64
WIRE -464 176 -512 144
WIRE -384 176 -336 144
WIRE 368 176 320 144
WIRE 448 176 496 144
WIRE -704 208 -704 176
WIRE -240 208 -240 176
WIRE 128 208 128 176
WIRE 592 208 592 176
WIRE -752 400 -800 400
WIRE -528 400 -752 400
WIRE -272 400 -320 400
WIRE -48 400 -272 400
WIRE 96 400 48 400
WIRE 320 400 96 400
WIRE 576 400 528 400
WIRE 800 400 576 400
WIRE -752 464 -800 464
WIRE -528 464 -752 464
WIRE -272 464 -320 464
WIRE -48 464 -272 464
WIRE 96 464 48 464
WIRE 320 464 96 464
WIRE 576 464 528 464
WIRE 800 464 576 464
FLAG -416 -160 0
FLAG -384 -320 out1
FLAG -512 -208 gate1
FLAG -640 -320 0
FLAG -704 -96 0
FLAG -544 -464 vin1
FLAG -688 -208 vpulse1
FLAG -704 208 0
FLAG -240 208 0
FLAG -688 64 junction1
FLAG -512 64 case1
FLAG -272 64 ambient1
FLAG 368 -160 0
FLAG 400 -320 out2
FLAG 272 -208 gate2
FLAG 144 -320 0
FLAG 80 -96 0
FLAG 240 -464 vin2
FLAG 96 -208 vpulse2
FLAG 128 208 0
FLAG 592 208 0
FLAG 144 64 junction2
FLAG 320 64 case2
FLAG 560 64 ambient2
FLAG 528 -368 tc#m2
FLAG -752 400 tj#M1
FLAG -752 464 tc#M1
FLAG -272 400 junction1
FLAG -272 464 case1
FLAG 96 400 tj#M2
FLAG 96 464 tc#M2
FLAG 576 400 junction2
FLAG 576 464 case2
DATAFLAG 192 704 ""
DATAFLAG 192 768 ""
DATAFLAG 672 704 ""
DATAFLAG 672 768 ""
DATAFLAG 1040 704 ""
DATAFLAG 1040 768 ""
DATAFLAG 1520 704 ""
DATAFLAG 1520 768 ""
SYMBOL nmos -464 -288 R0
SYMATTR InstName M1
SYMATTR Value IPB035N08N3  RthetaJA=62 Tambient={t_amb}
SYMBOL res -432 -448 R0
SYMATTR InstName R1
SYMATTR Value 5
SYMBOL voltage -640 -448 R0
SYMATTR InstName V1
SYMATTR Value 100
SYMBOL res -544 -224 R90
SYMATTR InstName R2
SYMATTR Value 50
SYMBOL voltage -704 -208 R0
SYMATTR InstName V2
SYMATTR Value 10
SYMBOL res -544 48 R90
SYMATTR InstName Rjc1
SYMATTR Value 1
SYMBOL res -368 48 R90
SYMATTR InstName Rca1
SYMATTR Value 61
SYMBOL res -368 160 R90
SYMATTR InstName Rcsa1
SYMATTR Value 20
SYMBOL voltage -240 80 R0
SYMATTR InstName Ta1
SYMATTR Value {t_amb}
SYMBOL bi -704 176 R180
SYMATTR InstName Pd1
SYMATTR Value I=V(out1)*Id(M1)+V(gate1)*Ig(M1)
SYMBOL nmos 320 -288 R0
SYMATTR InstName M2
SYMATTR Value IPB035N08N3  RthetaJA=62 Tambient={t_amb}
SYMBOL res 352 -448 R0
SYMATTR InstName R3
SYMATTR Value 5
SYMBOL voltage 144 -448 R0
SYMATTR InstName V3
SYMATTR Value 100
SYMBOL res 240 -224 R90
SYMATTR InstName R4
SYMATTR Value 50
SYMBOL voltage 80 -208 R0
SYMATTR InstName V4
SYMATTR Value 10
SYMBOL res 288 48 R90
SYMATTR InstName Rjc2
SYMATTR Value 1
SYMBOL res 464 48 R90
SYMATTR InstName Rca2
SYMATTR Value 61
SYMBOL res 464 160 R90
SYMATTR InstName Rcsa2
SYMATTR Value 20
SYMBOL voltage 592 80 R0
SYMATTR InstName Ta2
SYMATTR Value {t_amb}
SYMBOL bi 128 176 R180
SYMATTR InstName Pd2
SYMATTR Value I=V(out2)*Id(M2)+V(gate2)*Ig(M2)
SYMBOL SOAtherm-HeatSink 624 -368 R0
SYMATTR InstName U1
SYMATTR Value Rtheta=20 Tambient=25
SYMATTR InstName aluminum