How to make scaling circuit

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haitham al-saab

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Hi
I have a sensor that give me 0.25 if temp is 25
0.35 if it 35
and I wanna scale
using this eq
x=temp*0.0182
so if the temp 35 out put from sensor will be 0.35 and the out put from the scaling circuit will be 0.637 V
I use 7401 to make scaling

R1 = 1 K ohm
R2 = 1.82 k ohm

but I got 3 V I changed Ic It is still
so help meeeeee
 

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The circuit should works (with gain is 1.82, not 0.0182 as written in the equation).

Gain =R2/(R1+R2)*(1+R2/R1) = R2/R1

Which sensor are you using ? Did you try to input a voltage from a battery (or voltage supply) ?
 

the problem that the circuit give me 3 V all the tome why ?
vi = 0.25*1.8= 0.45 V NOT 3 !!
 

yah I checked
I really on't know where is the prop
I change the chip I add negative supply positive supply
and the problem not solved
could any one design other crt
 

The problem is not the circuit itself.
Could you post a photo of what you built ?
 

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