gopal_amlekar
New Member
Hello all,
I would like to get expert suggestions on whether it is possible to design a circuit for:
1. Temperature measurement using a NTC thermistor
2. 10-bit ADC (Max. input 3.3V)
3. Resolution of 0.1 degree celsius
4. Temperature range of -40 to +100 degree celsius
I studied a thermistor (10K, Beta value 2490) datasheet **broken link removed**.
If I use this thermistor in a voltage divider circuit biased from a 3.3V supply, I get a minimum step size of only 536uV for a 0.1 degree change in temperature.This step size varies through the range as the characteristics are nonlinear.
For a 10-bit ADC, minimum step size is 3.2mV.
Is there some way out or some other trick like amplifying voltage obtained across thermistor and / or changing gain of this amplifier dynamically etc. or some software manipulation / linearization etc.
Please guide..
Regards,
Gopal
I would like to get expert suggestions on whether it is possible to design a circuit for:
1. Temperature measurement using a NTC thermistor
2. 10-bit ADC (Max. input 3.3V)
3. Resolution of 0.1 degree celsius
4. Temperature range of -40 to +100 degree celsius
I studied a thermistor (10K, Beta value 2490) datasheet **broken link removed**.
If I use this thermistor in a voltage divider circuit biased from a 3.3V supply, I get a minimum step size of only 536uV for a 0.1 degree change in temperature.This step size varies through the range as the characteristics are nonlinear.
For a 10-bit ADC, minimum step size is 3.2mV.
Is there some way out or some other trick like amplifying voltage obtained across thermistor and / or changing gain of this amplifier dynamically etc. or some software manipulation / linearization etc.
Please guide..
Regards,
Gopal