Hi Tom, It might help to implement ADC offset and gain calibration as well. ADC offset and gain calibration are stored at 01A6h and 01A8h of the TLV, respectively. They are used to further correct the ADC value using the equation ADC(final) = ADC(VREF_calibrated)*(CAL_ADC_GAIN_FACTOR/32768)+CAL_ADC_OFFSET. However, even when using calibration on the temp sensor and the ADC, you should expect up to +/- 3 degrees Celsius error because of the nature of the sensor. Finally, further error can be introduced from noise on the internal ADC caused by fluctuations in the AVcc supply. You may want to check that this supply is steady. Other than that, the values you're seeing are still within the +/-3 degree Celsius range with the possible exception of the 92F value. Unforturnately, If you'd like highly accurate temperature readings, an external temp sensor is more appropriate. Best regards, Caleb Overbay
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