Application direction of smart pressure sensor

Pressure sensors are the most commonly used sensors in industrial practice. They are widely used in various industrial automation environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automation, aerospace, military, petrochemical, oil wells, electric power, ships, and machine tools. , pipelines and many other industries, the following briefly introduces the principle and its application.

Pressure sensors are also the most commonly used sensors in industrial practice. The output of a general common pressure sensor is an analog signal, and the analog signal is a signal that the information parameter appears as a continuous signal within a given range. Or in a continuous period of time, the characteristic quantity of its representative information may appear as an arbitrary value signal at any moment. The pressure sensors we usually use are mainly made of piezoelectric effect. Such sensors are also called piezoelectric sensors.

A typical pressure sensor is a Wheatstone bridge that outputs a signal that is proportional to pressure and then amplified by the PFA. There is a solid-state temperature sensor in the pressure sensor, which measures the temperature change of the pressure-sensitive sensor's light-sensing element in order to correct and compensate for the effect of the temperature change on the measured component error. The DTP also has an air pressure sensor that measures ambient air pressure changes in order to correct the effect of air pressure changes on the measurement. It can be seen that the intelligent sensor has a strong self-adaptive function. It uses one or several auxiliary sensors to detect changes in temperature, humidity, pressure, and other environmental conditions that affect the measurement accuracy, and uses the judgment and calculation functions of the micro-processing path. The main sensor measurement values ​​are corrected accordingly to get accurate measurement results.

At present, piezoresistive pressure sensors have been widely used, but its measurement accuracy is affected by nonlinearity and temperature. After an intelligent study of it, a single-chip microcomputer was used to correct the errors caused by nonlinearity and temperature changes. The experimental results show that 95% of the error caused by temperature change and nonlinearity is corrected. In the range of 10 and 60°C, the accuracy of the smart piezoresistive pressure sensor remains almost unchanged.

Automotive applications are still the largest application market for MEMS pressure sensors, with mainstream applications including tire pressure sensing systems (TPMS), inlet pressure sensing devices (MAP) and atmospheric absolute pressure sensing devices (BAP); Yole Developpement noted that automotive In the medical, medical, industrial, and high-end applications MEMS pressure sensor market, the average growth rate is about 4 to 7%, while the average growth rate (value scale) of the consumer application market is as high as 25% (the growth rate of the shipment is 38% ), mainly due to the new business opportunities brought by smartphones and tablet devices. MEMS pressure sensors have also found new applications in various fields. These include: in-cylinder pressure sensing for vehicles, continuous positive airway pressure (CPAP) for medical use, and consumption of smart phones and tablet devices. New applications (such as Samsung Galaxy Slll's indoor navigation function); the above emerging applications are still in their infancy, but it seems to have growth potential. YoleDeveloppement believes that MEMS pressure sensors will find new development paths in various fields to meet the needs of end users.

Honeywell's demanding automotive electronics, medical electronics and other applications use circumferential stress design and special metal alloys to customize pressure sensors. The measurement range is as high as 175,000 psi. It is safe to use, reliable, and accurate to 0.75%. The optional compensation temperature range for large pressure sensors is -54°C to 121°C [-65oF to 250oF] with an output of mV. High voltage output also has optional compensation temperature. There are also models for hazardous environments. All pressure sensors are shipped with calibration and traceability certificates. Potential applications for robust, reliable high-end instrumentation are oilfield geology and aeronautical research and development.