Hi
I need your help. My project is to design sensor that connected to op-amp.
temperature range from 35°C – 45°C, and ADC range 0 – 3.3V.

 

So what have you already done?

 

actually, nothing
I need some hints to begin designing

 

Well, I would start by reading the data sheet for the LM35

 

The sensor gives out 10mV per degC, 35C to 45C thats a voltage output of 350mV to 450mV,

 

.... so you need to amplify and offset those mV to get 0-3.3V (ideally). Read up on opamp theory.

 

I asked the doctor about it he tell me to get output voltage of opamp=0 when T=35, output voltage of opamp=3.3 when T=45

 

I asked the doctor about it he tell me to get output voltage of opamp=0 when T=35, output voltage of opamp=3.3 when T=45

We, instead just giving you the answer, in which case you learn nothing, are waiting for you to show some initiative and suggest a solution...

btw- I am a retired doctor (PhD). If you were my student, I would fail you if I learned that you just copied a solution that someone handed to you.

 

So now you should figure out how a op amp to do the amplifying as inverting and non-inverting, and then draw the circuit and attach it here.

 

You will note that everyone assumes this is home work, which means it gets treated differently. Make a serious attempt to solve the problem, draw a schematic you think might work, and you will go further. The more input you give the more hints toward solutions you will get, and the more you will learn.