Version 4
SHEET 1 880 680
WIRE 224 -32 -352 -32
WIRE 224 16 224 -32
WIRE -352 112 -352 -32
WIRE -160 160 -224 160
WIRE -64 160 -160 160
WIRE 48 160 16 160
WIRE 112 160 48 160
WIRE 224 160 224 96
WIRE 224 160 176 160
WIRE 368 160 224 160
WIRE 464 160 368 160
WIRE 496 160 464 160
WIRE -224 192 -224 160
WIRE 48 208 48 160
WIRE 224 208 224 160
WIRE 368 208 368 160
WIRE -352 320 -352 192
WIRE -224 320 -224 272
WIRE -224 320 -352 320
WIRE 48 320 48 272
WIRE 48 320 -224 320
WIRE 224 320 224 272
WIRE 224 320 48 320
WIRE 368 320 368 288
WIRE 368 320 224 320
WIRE 224 336 224 320
FLAG 224 336 0
FLAG 464 160 SenseLow
FLAG -160 160 Excitation
SYMBOL res 32 144 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 300R
SYMBOL res 240 112 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R2
SYMATTR Value 1Meg
SYMBOL res 384 304 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R3
SYMATTR Value 1Meg
SYMBOL cap 208 208 R0
SYMATTR InstName C1
SYMATTR Value 1n
SYMBOL schottky 176 144 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName D1
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL voltage -352 96 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 3
SYMBOL voltage -224 176 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value PULSE(0 3 0 0 0 50n 100n)
SYMBOL cap 32 208 R0
SYMATTR InstName C2
SYMATTR Value 200p
TEXT -386 360 Left 2 !.tran 1ms