Digital pressure gauge

Abstract

The invention discloses a digital pressure gauge, which is characterized in that the digital pressure gauge comprises a piezoresistive pressure transducer, a temperature detection circuit, two A / D conversion circuits and a microprocessor. On one hand, the microprocessor carries out sampling by the A / D conversion circuit I so as to obtain a voltage value corresponding to a current pressure signal; on the other hand, the microprocessor carries out sampling by the A / D conversion circuit II so as to obtain an output voltage value of the temperature detection circuit, and accurately calculates the temperature of the piezoresistive pressure transducer, then modifies the obtained values according to a temperature compensation method and a nonlinear compensation method so as to calculate more accurate pressure value, and finally, transmits digital signals by a communication module. The temperature detection circuit of the invention can accurately detect the temperatures of pressure sensitive components in the piezoresistive pressure transducer, thereby carrying out more accurate temperature compensation.

Description

Technical field [0001] The invention relates to a pressure measuring system, which is suitable for all products using piezoresistive pressure sensitive elements as sensors, especially pressure gauges, pressure transmitters and other products using piezoresistive sensors. Background technique [0002] Piezoresistive pressure sensor is an important sensor for measuring pressure at present. It is widely used in industrial control, automotive electronics, aerospace and other fields. It is made by using the piezoresistive effect of semiconductor materials and microelectronics technology, and has a sensitivity coefficient. Large, high resolution, high frequency response, small size and other characteristics, it is mainly used to measure pressure, acceleration and load and other parameters. Since semiconductor materials are very sensitive to temperature, piezoresistive pressure sensors have obvious temperature effects, and temperature compensation must be performed in actual application...

AI Technical Summary

Problems solved by technology

However, the chip PGA309 itself needs to use a temperature sensor to measure the temperature, and it is also unable to accurately measure the temperature of the pressure sensitive element in the pressure sensor.

[0006] In the Chinese invention patent "Nonlinear Hysteresis Intelligent Compensation Method and Intelligent Compensation System for Diffused Silicon Pressure Sensor" with the application number of 200710050622.5, a nonlinear hysteresis intelligent compensation method is proposed, and the compensation effect is better, but the algorithm is complex and The amount of calculation is large, and it is difficult to port to a low-power miniature pressure measurement system

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