Version 4
SHEET 1 1260 680
WIRE 784 -368 752 -368
WIRE 672 -336 672 -368
WIRE 400 -320 400 -336
WIRE 512 -320 512 -336
WIRE 784 -208 784 -368
WIRE 784 -208 736 -208
WIRE 816 -208 784 -208
WIRE 736 -96 736 -208
WIRE 752 -96 736 -96
WIRE 896 -80 896 -208
WIRE 896 -80 816 -80
WIRE 1008 -80 896 -80
WIRE 1152 -80 1072 -80
WIRE 1232 -80 1152 -80
WIRE 576 -64 496 -64
WIRE 688 -64 656 -64
WIRE 752 -64 688 -64
WIRE 688 -16 688 -64
FLAG 400 -240 0
FLAG 512 -240 0
FLAG 672 -336 0
FLAG 688 64 0
FLAG 496 16 0
FLAG 400 -336 3.3
FLAG 784 -112 3.3
FLAG 512 -336 -3.3
FLAG 784 -48 -3.3
FLAG 1072 -16 0
FLAG 1152 0 0
SYMBOL voltage 512 -336 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value -3.3V
SYMBOL voltage 400 -336 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value 3.3
SYMBOL res 768 -384 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value {X}
SYMBOL res 912 -224 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 3.3K
SYMBOL OpAmps\\LTC6254 784 -80 R0
WINDOW 3 51 44 Left 2
SYMATTR InstName U2
SYMBOL res 672 -80 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R6
SYMATTR Value 100K
SYMBOL res 704 80 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R7
SYMATTR Value 1K
SYMBOL voltage 496 -80 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
WINDOW 0 -13 2 Left 2
WINDOW 3 -246 133 Left 2
SYMATTR InstName V3
SYMATTR Value PULSE(-3.2 3.2 0 0 0 0.0002 0.0004)
SYMBOL diode 1008 -64 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL cap 1056 -80 R0
SYMATTR InstName C1
SYMATTR Value 330nf
SYMBOL res 1136 -96 R0
SYMATTR InstName R1
SYMATTR Value 560K
TEXT 424 -152 Left 2 !.tran 0.1
TEXT 864 -360 Left 2 !.step param X list 49.34 42.7 37.6