I´m about to implement a temperature compensation on a MC9S08QB4. I already read the application note AN3031 in order to get some information about how to get a higher accuracy and the calibration procedures. So far so good.
I think I also understood, that for my application the knowledge of an exact temperature is not important. The ADC value of the sensor is enough to compensate the error due to temperature changes !?
What I definitely do not understand is whether I have to bring the sensor value in relation to the current bandgap value or not. In other words: do I have to determine current V_DD by using the bandgap voltage in order to get a accurate sensor reading V_TEMP or is it nonsense in this case?