Application of FPGA in Intelligent Pressure Sensor Systems 3

In the formula, b1 and b0 are error correction factors. The error correction circuit model is shown in Figure 1, where x is the measured signal; Y is the system output; ε. K and i are unknown variables that affect the system. diode

The error correction process is as follows:

When S1 is closed, x=0， According to the error correction formula, equation (2) is obtained for zero point calibration of the system; diode

When S2 is closed, x=E (standard voltage), formula (3) is obtained for system gain error correction;

The error correction factor can be obtained by combining equations (2) and (3):  diode

When conducting actual measurements, S3 is closed. Using the calculated error correction factor and error correction formula (1), the corrected output signal y can be calculated.

2.2 Sensor temperature compensation method

For pressure sensors, the ambient temperature has a significant impact on their measurement results. In order to eliminate temperature induced errors, temperature compensation is required for the sensor signal. Compensate for sensor temperature by measuring the working temperature of the sensor. The temperature error correction model of the sensor is:  diode