TLV9002: NTC temperature senosr using TLV9002SIYCKR

Hello Kai,

Yes. I have seen that app note too.

But the simulation result is still the same.

If I adjust the output voltage span can I solve the gain issue?
Looking for your reply.

Hello Kai,
I accidentally pressed the This resolved my issue button

Hi Shibin,

Shibin Varghese said:

The resistance of NTC at -20°C is 68. 259K and the resistance at 7068259.59 is 2.27K

According to the Vishay's online calculator the correct resistances are:

The resistance at -20°C is "68259.59 Ohm".

The resistance at +70°C is "2227.98 Ohm".

Kai

Hello Kai,
That was a typo.
You are correct.

The resistance at -20°C is "68259.59 Ohm".
The resistance at +70°C is "2227.98 Ohm".

When I simply divide the output voltage of the circuit at 70°C by the input voltage at 70°C,  the gain is found to be 1.164.
When I divide the output voltage of the circuit at -20°C by the input voltage at -20°C, the gain is different.
This means the output of the circuit is not linear.
I believe this is because the input voltage at -20°C is 507mV and my required output voltage is 50mV.
the required output voltage at 70°C is 3.205V for an input voltage of 1.164V.
Can I solve this issue by changing the output voltage span?.