Version 4
SHEET 1 2364 996
WIRE -32 -128 -160 -128
WIRE 48 -128 -32 -128
WIRE 320 -128 128 -128
WIRE 320 -96 320 -128
WIRE -160 -64 -160 -128
WIRE 320 -64 320 -96
WIRE 320 32 320 0
WIRE -160 80 -160 16
WIRE 320 80 320 32
FLAG -160 80 0
FLAG 320 80 0
FLAG 320 -96 A
FLAG 320 32 K
FLAG -32 -128 gen
SYMBOL res 32 -112 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R1
SYMATTR Value {Rv}
SYMBOL voltage -160 -80 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
WINDOW 3 -15 208 Left 2
SYMATTR Value PULSE({Vmin} {Vmax} 1µs {tf} {tf} 3µs)
SYMATTR InstName V1
SYMBOL diode 304 -64 R0
SYMATTR InstName D1
SYMATTR Value {Diode}
SYMATTR Prefix X
TEXT -192 -560 Left 2 !.tran 0 30µ 10µ 10n
TEXT -192 -416 Left 2 !.param Vmax=0.67*Vdrm   Vmin=-100V
TEXT -192 -464 Left 2 !.param didt=10Meg
TEXT -192 -512 Left 2 !.param Vdrm=1200V Itav=40A
TEXT -192 -384 Left 2 !.param Rv=Vmax/Itav
TEXT -192 -352 Left 2 !.param tf=Itav/didt
TEXT 464 -112 Left 2 ;.lib 40EPS12.lib
TEXT -192 192 Left 2 !.subckt 1 A K\nD               A K             ZD\nR               A K             1200k\n.model ZD d (Is=10p N=1.13 Rs=7.6m BV=1200 Ibv=5µ Cjo=20n Tt=0.18µ)\n.ends
TEXT 464 -160 Left 2 !.step param Diode list 1 2 3 4
TEXT -192 368 Left 2 !.subckt 2 A K\nD               A K             ZD\nR               A K             1200k\n.model ZD d (Is=10p N=1.13 Rs=7.6m BV=1200 Ibv=5µ Cjo=20n Tf=4µ)\n.ends
TEXT -192 544 Left 2 !.subckt 3 A K\nD               A K             ZD\nR               A K             1200k\n.model ZD d (Is=10p N=1.13 Rs=7.6m BV=1200 Ibv=5µ Cjo=40n)\n.ends
TEXT -192 768 Left 2 !.subckt 4 A K\nD               A K             ZD\nR               A K             1200k\n.model ZD D (is = 1.43733E-008 n = 1.80829 rs = 0.0414712\n+ eg = 1.11 xti = 3 tnom = 27 cjo = 2.8119E-011 vj = 0.700053\n+ m = 0.346714 fc = 0.5 tt = 4.10886E-006\n+ bv = 1100 ibv = 10 af = 1 kf = 0)\n.ends
TEXT 576 848 Left 2 ;1N4007