Version 4
SHEET 1 880 680
WIRE -224 80 -256 80
WIRE -176 80 -224 80
WIRE 16 80 -96 80
WIRE 48 80 16 80
WIRE -256 144 -256 80
WIRE 48 144 48 80
WIRE -256 256 -256 224
WIRE 48 256 48 208
WIRE 48 256 -256 256
WIRE -256 272 -256 256
WIRE -224 384 -256 384
WIRE -176 384 -224 384
WIRE 16 384 -96 384
WIRE 48 384 16 384
WIRE 48 432 48 384
WIRE -256 448 -256 384
WIRE -256 560 -256 528
WIRE 48 560 48 496
WIRE 48 560 -256 560
WIRE -256 576 -256 560
FLAG -256 272 0
FLAG -256 576 0
FLAG -224 80 1
FLAG 16 80 2
FLAG -224 384 1A
FLAG 16 384 2A
SYMBOL diode 32 208 M180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMATTR Value T15KE12CA
SYMATTR Prefix X
SYMBOL res -192 96 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R1
SYMATTR Value 100
SYMBOL voltage -256 128 R0
WINDOW 3 -14 182 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value PWL(0 0 1m -50 3m 50 4m  0)
SYMBOL res -192 400 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R2
SYMATTR Value 100
SYMBOL voltage -256 432 R0
WINDOW 3 -14 182 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value PWL(0 0 1m -50 3m 50 4m  0)
SYMBOL X_suppr_dio_bi 32 432 R0
SYMATTR InstName U1
SYMATTR Value T15KE12CA
TEXT -272 -40 Left 2 !.lib 15KE12CA.MOD
TEXT -272 -80 Left 2 !.tran 0 4m 0 1u