What is a pressure sensor?

(One) Core Components and Functions
The core component of a pressure transmitter is the pressure sensitive element, commonly known as a metal thin-film strain gauge and a silicon piezoresistive element. Metal thin-film strain gauges have good mechanical strength and stability, and when subjected to pressure, the metal thin film will undergo a slight deformation, causing its resistance value to change. The silicon piezoresistive element, on the other hand, utilizes the piezoresistive effect of silicon material. When pressure is applied to the silicon piezoresistive element, its internal resistance value will change with the change in pressure. The function of these pressure sensitive elements is to convert the measured pressure into an electrical signal output, providing a foundation for subsequent signal processing and transmission.
According to relevant data, the silicon piezoresistive element is increasingly widely used in pressure transmitters, with an accuracy of up to ±0.02% FS and a stability of better than ±0.05% FS. This high accuracy and high stability make pressure transmitters able to accurately measure various pressure parameters in industrial production, providing reliable data support for the control and optimization of production processes.
(Two) Signal Conversion Process
When pressure is applied to the sensitive element, strain will occur, causing the resistance value to change. By measuring this resistance change and undergoing a series of processing, an electrical signal proportional to the pressure can be obtained. For example, in the strain gauge sensor, the strain gauge is bonded to a flexible diaphragm. When pressure is applied to the diaphragm, it deforms, causing the strain gauge's resistance to change. This resistance change is converted into an electrical signal.
In the piezoelectric sensor, piezoelectric materials (such as quartz) are used to sense pressure. When pressure is applied to the piezoelectric material, a charge is generated, which is converted into an electrical signal. Whether it is a strain gauge sensor or a piezoelectric sensor, the signal conversion process requires amplification and conditioning to improve the accuracy and stability of the signal.
(Three) Capacitance Change and Signal Output
When the pressure on both sides is unequal, the measuring diaphragm will deform. The displacement of the dia The ceramic pressure transmitter uses a technologically advanced imported ceramic sensor, which has two significant technical differences compared to the conventional pressure transmitters currently in use: one is the measurement element made of a new high-precision ceramic material; the other is that the measurement element is completely solid without any intermediate liquid. It has the characteristics of strong resistance to overloading and impact, high stability, small temperature drift, and wide applicability.
The strain-based pressure transmitter uses a special adhesive to bond the strain gauges together to produce mechanical strain. When the body is subjected to force changes, the resistive strain gauges will also undergo certain deformation, which will affect the resistance value and cause a change in the voltage across the resistor. This transmitter has high accuracy, good long-term stability, and is easy to install; it is resistant to shock and impact; has strong anti-interference capabilities, reverse polarity protection, and overpressure protection.
(ii) Analysis of the characteristics of each type
The diffusion silicon pressure transmitter has standard threaded pressure measurement methods, a full stainless steel structure, and other features. Its sensing, sensitive conversion, and detection are integrated into one, with no mechanical linkage conversion stages, resulting in very small non-repeatability and hysteresis errors. Its linearity is also excellent, resulting in high overall accuracy. Its frequency response is high, as the sensitive diaphragm silicon material has a natural frequency of 50 kHz, and the manufacturing process uses integrated technology, allowing the diaphragm's effective area to be very small. Combined with a rigid structure and a special front-mounted installation design, the sensor's frequency response is very high, with a usable bandwidth from zero to 100 kilohertz. Its resistance to electrical breakdown is good, and it can withstand a voltage shock of up to 1500 V AC. Its reliability is high, as the diaphragm displacement is in the micron range and there is no mechanical wear, fatigue, or aging, resulting in a long average time between failures. Its corrosion resistance is good, as the diffusion silicon material has excellent chemical corrosion resistance, even if the pressure-sensing surface is not isolated, it can still adapt to various media in