Version 4
SHEET 1 1164 1128
WIRE -256 336 -432 336
WIRE -32 336 -64 336
WIRE 160 336 -32 336
WIRE 240 336 160 336
WIRE -432 352 -432 336
WIRE -32 352 -32 336
WIRE 160 352 160 336
WIRE -256 432 -288 432
WIRE -32 432 -64 432
WIRE 48 432 -32 432
WIRE 160 432 112 432
WIRE -432 448 -432 432
WIRE -288 464 -288 432
WIRE 160 528 160 512
FLAG -432 448 0
FLAG -288 464 0
FLAG 240 336 OUT
FLAG -432 336 IN
FLAG 160 528 0
SYMBOL LT1021-5 -160 384 R0
SYMATTR InstName U1
SYMBOL voltage -432 336 R0
SYMATTR InstName V1
SYMATTR Value 12
SYMBOL res -48 336 R0
SYMATTR InstName R1
SYMATTR Value 27K
SYMBOL res 144 336 R0
SYMATTR InstName R2
SYMATTR Value {50K*(1-x)}
SYMBOL res 144 416 R0
SYMATTR InstName R3
SYMATTR Value {50K*x}
SYMBOL diode 48 448 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D1
SYMATTR Value 1N4148
TEXT -200 528 Left 2 !.dc TEMP -50 125 1\n.step param X list .2 .5 .8