Temperature sensor accuracy improvement using a PIC MCU
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The accuracy of most of the current IC temperature sensors is about ±1°C at room temperature. However, at hot and cold temperatures, the uncertainty increases exponentially, resulting in a parabolic-shaped error curve. This application note describes a technique to enhance the accuracy of the sensor by modeling the error curve and use it to compensate for the sensor drift at a wide range of operating temperature. A PIC MCU is used to compute the equation for the curve and apply it to the sensor output to provide a more accurate temperature reading.