There are many types of pressure sensors, which can be classified into different categories according to different classification standards. Here are two of the most common pressure sensors:

1. Diffuse silicon pressure sensor

The working principle of a diffused silicon pressure sensor is based on the piezoresistive effect. Using the principle of piezoresistive effect, the pressure of the measured medium directly acts on the diaphragm of the sensor (stainless steel or ceramic), causing the diaphragm to produce a micro displacement proportional to the medium pressure, resulting in a change in the resistance value of the sensor. The electronic circuit detects this change and converts it into a standard measurement signal corresponding to this pressure.

Diffuse silicon pressure sensors have small volume, light weight, and stable performance, making them suitable for making small range transmitters. They are mainly used in industries such as process control systems, pressure calibration instruments, hydraulic systems, biomedical instruments, hydraulic systems and valves, liquid level measurement, refrigeration equipment, and HVAC control.

2. Capacitive pressure sensor

Capacitive pressure sensor is a type of pressure sensor that uses capacitive sensing elements to convert the measured pressure into an electrical output that is related to it. It generally uses a circular metal film or a metal plated film as one electrode of a capacitor. When the film deforms under pressure, the capacitance formed between the film and the fixed electrode changes, and an electrical signal related to voltage can be output through a measurement circuit.

Capacitive pressure sensors have the characteristics of low input energy, high dynamic response, small natural effects, and good environmental adaptability. Among them, ceramic capacitive pressure sensors can be widely used for pressure detection in various media such as water, gas, and liquid due to their advantages of corrosion resistance, impact resistance, no hysteresis, and strong medium compatibility.

Pressure is one of the important parameters in production and life, and pressure sensors are widely used in various industrial automation environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automation, petrochemicals, oil wells, electricity, ships, machine tools, pipelines and many other industries.