How does one compensate for temperature drift in analog sensors?

Temperature drift in analog sensors refers to the change in the sensor's output signal due to variations in temperature, even when the measured variable remains constant. This can lead to inaccurate readings and affect the performance of control systems. Several techniques can be used to compensate for temperature drift. One common method is to use a temperature compensation circuit. This involves incorporating a temperature-sensitive component, such as a thermistor or a temperature sensor IC, into the sensor's signal conditioning circuitry. The temperature-sensitive component provides a signal that varies with temperature, and this signal is used to correct the sensor's output for temperature drift. For example, a thermistor with a negative temperature coefficient (NTC) can be used to compensate for the positive temperature coefficient of a pressure sensor. Another approach is to use software compensation. This involves measuring the temperature of the sensor and applying a correction factor to the sensor's output based on a pre-determined temperature calibration curve. The calibration curve is typically obtained by characterizing the sensor's temperature drift in a controlled environment. In some cases, self-calibration techniques can be used. This involves periodically calibrating the sensor against a known standard or reference, allowing it to automatically compensate for any drift. The compensation method is dependent on the sensor.