Instrumentation Controls Lab (EE2327L) Practice Exam

The main idea is that pressure sensors don’t respond the same way at every temperature. The electronics inside a transducer have temperature coefficients that shift both the zero-pressure output (offset) and the slope of the response (gain or sensitivity) as temperature changes. If you calibrate at one temperature and use the sensor over a range of temperatures, those shifts cause readings to drift from true pressure.

Temperature compensation uses the measured temperature during calibration (or during operation) to adjust the raw signal so the calculated pressure stays accurate across the expected temperature range. In practice, you model the output as a function of both the electrical signal and temperature (for example, include terms for offset versus temperature and gain versus temperature, or even cross-terms), and then apply that correction in hardware or software. This is why compensation is applied during calibration: to correct for temperature-induced changes and maintain accurate pressure readings.

Humidity isn’t the primary reason for this adjustment, and calibrating a separate thermal sensor or focusing on battery life doesn’t address the pressure sensor’s temp–driven offset and gain changes.