Pressure sensor is a kind of pressure sensor that can be used in steel, chemical and other fields to measure pressure, and can realize automatic pressure control when used together with pressure regulator.
Diffusion Silicon Pressure Sensor /Introduction to the principle
Diffusion silicon pressure sensor is based on the principle of piezoresistive effect, using integrated process technology through doping and diffusion, along the characteristic crystal direction on the single crystal silicon wafer, to form a strain resistance to form a Wheatstone bridge.Using the elastic mechanical properties of silicon material, anisotropic micromachining is performed on the same silicon material, and a diffused silicon sensor integrating force-sensing and force-electric conversion detection is fabricated.
The pressure of the diffused silicon pressure sensor acts directly on the diaphragm of the sensor (stainless steel or ceramic), causing the diaphragm to produce a micro-displacement proportional to the pressure of the medium, and the resistance value of the sensor changes. The electronic circuit detects this change and converts it. A standard measurement signal corresponding to this pressure is output.
Diffusion Silicon Pressure Sensor Features
1. Suitable for making small-scale transmitters
The piezoresistive effect of the force-sensitive resistor of the silicon chip has no dead zone in the low range near the zero point, and the range of the pressure sensor can be as small as several Kpa.
2. High output sensitivity
The sensitivity factor of silicon strain resistance is 50 to 100 times higher than that of metal strain gauge, so the sensitivity of the corresponding sensor is very high, and the general range output is about 100mv. Therefore, there are no special requirements for the interface circuit, and it is more convenient to use.
3. High precision
Since the sensing, sensitive conversion and detection of the sensor are realized by the same component, there is no intermediate conversion link, and the repeatability and hysteresis errors are small. Since the monocrystalline silicon itself has high rigidity and small deformation, good linearity is ensured.
4. Since the unisexual deformation of the work is as low as the order of micro-strain, the maximum displacement of the elastic chip is in the order of sub-micron, so there is no wear, no fatigue, no aging, and the life span is as long as 1×107 pressure cycle, with stable performance and high reliability.
5. Due to the excellent chemical corrosion resistance of silicon, even non-isolated diffused silicon pressure sensors have the ability to adapt to various media to a considerable extent.
6. Since the chip adopts an integrated process and has no transmission components, it is small in size and light in weight.
Diffusion Silicon Pressure Sensor Precautions for use
1.When over-range or under-range is selected, the amplitude should be controlled within ±30%FS.
2.The pressure mode is divided into gauge pressure, absolute pressure and sealing pressure, which can be selected reasonably according to the needs.
3.Confirm the maximum overload of the system. The maximum overload of the system should be less than the overload protection limit of the sensor, otherwise it will affect the service life of the product and even damage the product.
4.Do not touch the diaphragm with any hard objects, otherwise it will cause the diaphragm to rupture.
5.The material and process of manufacturing the negative pressure core are not the same as the positive pressure, so the negative pressure core cannot be replaced by the gauge pressure core.
6.Please check the instruction manual carefully before installation to avoid damage to the product caused by wrong installation.
7.Improper use can lead to danger and personal injury.
8.The core is pulled out from the housing, and it is forbidden to pull the wires and the tube legs.
Diffusion Silicon Pressure Sensor Applications
Diffusion silicon pressure sensors are mainly used in process control systems, pressure calibration instruments, hydraulic systems, biomedical instruments, hydraulic systems and valves, liquid level measurement, refrigeration equipment and HVAC control industries. It can be said that all industries with high automation requirements , may use diffused silicon pressure sensors.
Post time: Aug-15-2022