NTC Thermistor with PWM

[shredder]

Hey ppl.

I have recently been assigned the task of generating a thermistor digital circuit without an AD.


What it will be is a comparator with inputs from (varying PWM) out of a PIC & the input from the thermistor

The comparator will be linked back into the PIC and calculate whether the temperature is higher or lower.




Ive scoured the web but I can't find any schematics for the circuit.

Does anyone know where I could find one relating to tackling the problem similar to this way?


Many Thanks,
Ryan.

[shredder]

Could someone point me in the direction of some useful links

regarding using thermistors with opamps-buffers/comparators and capacitors, please?


I dont know where to start but after scouring the web I dont know where to start. Thank you.

[Pic_User]

Hi Ryan,

Here is a place to start:
Temperature Measurement Circuits for Embedded Applications
http://ww1.microchip.com/downloads/e...tes/00929a.pdf

This shows capacitors used with thermistors:
Microchip Technology Inc. Application note AN685
Thermistors in Single Supply Temperature Sensing Circuits
http://ww1.microchip.com/downloads/e...tes/00685b.pdf

-Adam-