Direct and Flexible Temperature Measurement and Thermal Compensation methods for Piezoresistive Pressure Sensor

Typically, an additional temperature component is needed to implement effective thermal compensation for piezoresistive pressure sensor. In this paper, the equivalent input resistance mathematical model of Wheatstone bridge for the piezoresistive pressure sensor is discussed in detail in a dynamic state. A thermal compensation model and a temperature measurement model relying only on the pressure sensor signals are proposed. The simulation and practical test results indicate that the maximum absolute errors for measured temperature is 0.15°C and the maximum full range error for pressure is 0.04% FS. the proposed thermal compensation model and temperature measurement model are fully proved to be effective with the less computational effort and without any additional temperature sensor. Especially, the proposed thermal compensation model which is not directly relevant to temperature factor is highly flexible for the practical application.