Version 4
SHEET 1 880 680
WIRE -48 -48 -48 -80
WIRE 112 -32 64 -32
WIRE 240 -32 192 -32
WIRE -192 64 -288 64
WIRE -48 64 -48 32
WIRE -48 64 -112 64
WIRE 64 64 64 -32
WIRE 64 64 -48 64
WIRE 128 64 64 64
WIRE 240 80 240 -32
WIRE 240 80 192 80
WIRE 336 80 240 80
WIRE -288 96 -288 64
WIRE 64 96 -48 96
WIRE 128 96 64 96
WIRE -48 128 -48 96
WIRE 64 192 64 96
WIRE 112 192 64 192
WIRE 240 192 240 80
WIRE 240 192 192 192
WIRE -288 208 -288 176
WIRE -48 240 -48 208
WIRE 64 240 64 192
WIRE 64 352 64 320
FLAG -48 -80 0
FLAG -48 240 0
FLAG 64 352 0
FLAG -288 208 0
FLAG 336 80 Ua
FLAG -288 64 Ue
DATAFLAG 288 80 "round($*10k)/10k"
DATAFLAG -224 64 "round($*10k)/10k"
DATAFLAG 16 96 "round($*10k)/10k"
SYMBOL Opamps\\opamp 160 16 R0
SYMATTR InstName U1
SYMATTR SpiceLine Aol=1000K
SYMBOL Misc\\EuropeanResistor -208 80 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R1
SYMATTR Value 200k
SYMBOL Misc\\EuropeanResistor 96 -16 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R2
SYMATTR Value 100k
SYMBOL Misc\\EuropeanResistor 48 224 R0
SYMATTR InstName R3
SYMATTR Value 100k
SYMBOL Misc\\EuropeanResistor 96 208 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R4
SYMATTR Value 100k
SYMBOL current -48 32 M180
WINDOW 0 24 80 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName I1
SYMATTR Value {Ib}
SYMBOL current -48 128 R0
SYMATTR InstName I2
SYMATTR Value {Ib}
SYMBOL voltage -288 80 R0
SYMATTR InstName V1
SYMATTR Value 1
TEXT -304 -184 Left 2 !.param Ib=1u
TEXT -304 -152 Left 2 !.op
TEXT -64 -184 Left 2 !.lib opamp.sub
TEXT -304 -312 Left 2 ;Ua=(-Ue*R2/R1+Ib*R2-Ib*(R1+R2)*R3*R4/(R1*(R3+R4)))/(1-R3*(R1+R2)/(R1*(R3+R4)))\n \nR1=2*R R2=R3=R4=R --> Ua = -Ue*2 +Ib*R