Common pressure sensor application principles
Release time：2020-04-13 Clicks：655
The pressure sensor belongs to the most commonly used pressure sensor, which has certain applications in the fields of industry, electronics, chemical, medical, military, petroleum and other fields. There are many types of pressure sensors, which can be divided into piezoresistive pressure sensors, ceramic pressure sensors, diffused silicon pressure sensors, etc. Today, we will give you a detailed introduction to the working principle of common pressure sensors. I hope that I can help To everyone, if you have needs, you can contact us with Boyi Pneumatics, Baidu search.
1. Piezoresistive force sensor: The resistance strain gauge is one of the main components of the piezoresistive strain sensor. The working principle of metal resistance strain gauge is the phenomenon that the resistance of the strain resistance adsorbed on the base material changes with the mechanical deformation, which is commonly known as the resistance strain effect.
2. Ceramic pressure sensor: The ceramic pressure sensor is based on the piezoresistive effect. The pressure directly acts on the front surface of the ceramic diaphragm, causing a slight deformation of the diaphragm. The thick film resistor is printed on the back of the ceramic diaphragm and connected into a Wheatstone The bridge, due to the piezoresistive effect of the varistor, causes the bridge to generate a highly linear voltage signal proportional to the pressure and proportional to the excitation voltage. The standard signal is calibrated to 2.0 / 3.0 / 3.3mv according to the different pressure ranges / v, etc., compatible with strain sensors.
3. Diffusion silicon pressure sensor: The working principle of the diffusion silicon pressure sensor is also based on the piezoresistive effect. Using the principle of piezoresistive effect, the pressure of the measured medium directly acts on the sensor's diaphragm (stainless steel or ceramic), so that the diaphragm is generated and the medium The micro-displacement proportional to the pressure changes the resistance value of the sensor, detects this change by electronic circuit, and converts and outputs a standard measurement signal corresponding to this pressure.
4. Sapphire pressure sensor: The use of strain resistance type working principle, using silicon-sapphire as the semiconductor sensitive element, has unparalleled measurement characteristics. Therefore, semiconductor sensitive components made of silicon-sapphire are not sensitive to temperature changes, and they have very good operating characteristics even under high temperature conditions; sapphire has strong radiation resistance; in addition, silicon-sapphire semiconductor sensitive components have no pn drift.
5. Piezoelectric pressure sensor: The piezoelectric effect is the main working principle of the piezoelectric sensor. The piezoelectric sensor cannot be used for static measurement, because the charge after external force is only saved when the loop has an infinite input impedance . The actual situation is not the case, so this determines that the piezoelectric sensor can only measure dynamic stress.
