Quote Originally Posted by rsocor01 View Post
Hi,
If I understand correctly your question, when you get .90V out of the temperature sensor that corresponds to 90deg F and 1.20V corresponds to 120deg F. A very simple linear equation crossing the origin (0,0) would be
Temperature = 100 * Voltage
Use this simple equation for Temperature in the range between 90F and 120F. I hope this helps.
Robert

I need the fan to come on at 90 deg and output a PWM signal of 50% at that temp. Then increase the duty cycle of that PWM signal as temperature (voltage) increases to a maximum of 100% at 120deg and above.