Version 4
SHEET 1 880 680
WIRE 144 -96 0 -96
WIRE 320 -96 224 -96
WIRE 416 -96 320 -96
WIRE 544 -96 416 -96
WIRE 320 -64 320 -96
WIRE 416 -64 416 -96
WIRE 544 16 544 -96
WIRE 0 64 0 -96
WIRE 320 64 320 16
WIRE 0 240 0 144
WIRE 144 240 0 240
WIRE 320 240 320 144
WIRE 320 240 224 240
WIRE 416 240 416 16
WIRE 416 240 320 240
WIRE 544 240 544 80
WIRE 544 240 416 240
WIRE 320 304 320 240
FLAG 320 304 0
SYMBOL voltage 320 48 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 12
SYMBOL Misc\\signal 0 48 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value PULSE(0 325 0 1n 1n .5u 1u)
SYMBOL res 240 -112 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 66k
SYMBOL res 240 224 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 66k
SYMBOL res 400 -80 R0
SYMATTR InstName R4
SYMATTR Value 470
SYMBOL res 304 -80 R0
SYMATTR InstName R3
SYMATTR Value 2k7
SYMBOL cap 528 16 R0
SYMATTR InstName C1
SYMATTR Value 100p
TEXT -32 328 Left 2 !.tran 100u