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LM35 how to get 0-10V output

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Zofim239

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Hi...
How can I get a 0-10v voltage range for this circuit?
I just want a range of temperature from 0ºc till 150ºc, that's why I'm using a positive voltage value for the op-amp. I'm using a 24v power supply.
The op-amp gives a 0-15 voltage range and it works ok, but I don't need the 5v above 10v.
what should I add to it?

fef56bb357a1ebd3199cda5eac06194bo.jpg


3592568a04d93816b07636380c9f52cco.png


Please Help me!
 
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I this with my understanding of your circuit if your circuit is working as you shown in the meter reading....you need to keep LM35 at 100 deg. centagate.....should give you 10V.....Now if you want to change the range from 0 to 15 volts to 0 to 10v for 0 to 150 deg then .....there are two alternative

1) Use voltage devider network at the output of the opamp
Vo'= (R12/(R11+R12))* Vo you want Vo' =10v when you have Vo =15v so R12/(R12+R11) = 0.66666....so keep you will get R11 = 0.5R12 so keep R11 = 1Kohm and R12 = 2Kohm....

2) you can reduce the feedback resistor of your circuit because it is non-inverting amplier configuaration of the circuit so gain will be ( 1 + rf/ri) .....in your case rf= R2 + RPot =16kohm + 2Kohm =18k ohm and ri= R1 =2 ohm so the gain of circuit will be 1+ 18/2 = 10 .....now to map 1.5v to 10v conversion you need to keep the gain as 10/1.5 = 6.66 so you need ....(1+Rf/Ri) =6.666 = Rf/Ri =5.666 you you should try to keep you Ri =2Kohm only you get Rf=11.33 Kohm so if you change your R2 =16 Kohm resistnace toR2=10K and adjust the 2K pot .....your range will get controlled to 0 to 10V

Circuit is attached for voltage devider with the post refer it.....3592568a04d93816b07636380c9f52cco1.png

I think should help .....


Good Luck
 
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