For accurate temperature measurement, you must account for the inaccuracies of the electronics and the inaccuracies of the sensors.
Typically, most of the inaccuracy occurs at the sensor level. Temperature accuracy in uncalibrated sensors can range from as much as 2 degrees Celsius (in diodes and transistors) to 0.1 degrees Celsius (in precision glass thermometers).
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With the LTC2983, Linear Technology is able to provide very accurate temperature sensors by minimizing errors on the electronics side of things. This temperature sensor is able to provide better than 0.1 degrees Celsius of accuracy.
To learn more about how Linear Technology achieves this level of temperature accuracy, watch the video above.