Version 4
SHEET 1 1536 680
WIRE -80 -128 -144 -128
WIRE -32 -128 -80 -128
WIRE -144 -96 -144 -128
WIRE -32 -96 -32 -128
WIRE -144 16 -144 -16
WIRE -32 16 -32 -16
WIRE 800 32 336 32
WIRE 800 64 800 32
WIRE 336 112 336 32
WIRE -112 128 -144 128
WIRE 288 128 -112 128
WIRE 288 176 256 176
WIRE 800 176 800 144
WIRE 256 208 256 176
WIRE 336 288 336 192
WIRE -144 384 -144 128
WIRE 336 400 336 368
WIRE -144 496 -144 464
FLAG 336 400 0
FLAG 800 176 0
FLAG -32 16 0
FLAG 256 208 0
FLAG -144 16 0
FLAG -144 496 0
FLAG -80 -128 IN
FLAG -112 128 TRIG
SYMBOL voltage -32 -112 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value PULSE(0 24 0 2m 2m 1n)
SYMBOL voltage 336 272 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value PULSE(0 12 0 1n 1n 2u 4u)
SYMBOL res 784 48 R0
SYMATTR InstName R1
SYMATTR Value 1k
SYMBOL sw 336 208 M180
SYMATTR InstName S1
SYMATTR Value S15V
SYMBOL res -160 -112 R0
SYMATTR InstName R4
SYMATTR Value 1k
SYMBOL bv -144 368 R0
SYMATTR InstName B1
SYMATTR Value V(TRIG)=if(V(IN)<15, fall, 15, 0)
TEXT -144 544 Left 2 !.tran 4m
TEXT -144 576 Left 2 !.model S15V SW (Vt=15V)