Version 4
SHEET 1 880 680
WIRE -32 -144 -112 -144
WIRE 224 -144 -32 -144
WIRE 304 -144 224 -144
WIRE 304 -128 304 -144
WIRE -112 -96 -112 -144
WIRE 304 -32 304 -48
WIRE -112 16 -112 -16
WIRE 0 16 -112 16
WIRE 112 16 80 16
WIRE 160 16 112 16
WIRE -112 64 -112 16
WIRE -112 64 -256 64
WIRE -256 80 -256 64
WIRE -112 80 -112 64
WIRE 112 80 112 16
WIRE 224 80 224 -144
WIRE 160 96 160 16
WIRE 192 96 160 96
WIRE -32 112 -32 -144
WIRE 64 112 -32 112
WIRE 304 112 256 112
WIRE 352 112 304 112
WIRE 192 128 160 128
WIRE 304 128 304 112
WIRE 224 160 224 144
WIRE -256 176 -256 160
WIRE -112 176 -112 160
WIRE -112 176 -256 176
WIRE -112 224 -112 176
WIRE 0 224 -112 224
WIRE 112 224 112 160
WIRE 112 224 80 224
WIRE 160 224 160 128
WIRE 160 224 112 224
WIRE -112 240 -112 224
WIRE 304 240 304 208
WIRE -112 336 -112 320
WIRE 304 336 304 304
FLAG 304 -32 0
FLAG -112 336 0
FLAG 304 336 0
FLAG 224 160 0
FLAG 352 112 out
IOPIN 352 112 Out
SYMBOL potentiometer 128 176 R180
WINDOW 0 36 32 Left 2
WINDOW 3 28 99 Left 1
SYMATTR InstName P1
SYMATTR Value Rtot=470K wiper={x}
SYMBOL res 96 0 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 1k
SYMBOL res 96 208 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 1k
SYMBOL res -128 -112 R0
SYMATTR InstName R3
SYMATTR Value 22k
SYMBOL res -128 224 R0
SYMATTR InstName R4
SYMATTR Value 22k
SYMBOL res -128 64 R0
SYMATTR InstName R5
SYMATTR Value 10
SYMBOL res -272 64 R0
SYMATTR InstName R6
SYMATTR Value 0.01
SYMBOL voltage 304 -144 R0
WINDOW 0 50 26 Top 2
WINDOW 3 50 87 Bottom 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 15
SYMBOL res 288 112 R0
SYMATTR InstName R7
SYMATTR Value 10k
SYMBOL LED 288 240 R0
SYMATTR InstName D1
SYMATTR Value QTLP690C
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL Opamps\\UniversalOpamp2 224 112 R0
SYMATTR InstName U1
TEXT -240 -256 Left 2 ;.tran 100m
TEXT -240 -288 Left 2 !.lib potentiometer.sub
TEXT -240 -232 Left 2 !.op
TEXT 144 -256 Left 2 !.step param x 0 1 1m
TEXT 144 -288 Left 2 !.param x=0