Pressure Sensor

A pressure sensor is a device that converts the pressure of a gas or liquid into a measurable electrical signal. It converts physical quantities into electrical quantities, facilitating data collection, processing, and control in electronic systems. Due to their wide application, pressure sensors are often called the "nerve endings of industry" and are commonly found in fields such as automation, automotive, medical, and consumer electronics.

Working Principle

The core of a pressure sensor is a pressure-sensitive element, such as a diaphragm, strain gauge, or piezoelectric crystal. When external pressure acts on the sensitive element, it undergoes a slight deformation, resulting in a change in resistance, capacitance, or charge. The sensor's internal circuitry amplifies this change and converts it into a voltage, current, or digital signal, enabling pressure detection and transmission.

Main Types

Depending on the detection method, pressure sensors primarily include strain gauge, capacitive, piezoelectric, resonant, and fiber optic types. Strain gauges have a mature structure and are the most widely used; capacitive types offer high sensitivity and low power consumption; piezoelectric types are suitable for dynamic pressure measurement; resonant types offer excellent accuracy and stability; and fiber optic types offer immunity to electromagnetic interference and are suitable for specialized environments. Application Scenarios

Typical Applications for Pressure Sensors

• Industrial control: hydraulic systems, pneumatic devices, process monitoring, and automated control.
• Automotive: tire pressure monitoring systems, engine intake air pressure, and oil pressure monitoring.
• Medical equipment: non-invasive blood pressure monitors, ventilators, and patient monitoring systems.
• Aerospace: altimeters, aircraft cabin pressure, and fuel pressure monitoring.
• Consumer electronics: barometers in smartphones and smartwatches for positioning and altitude measurement.
• Energy: oil and gas extraction, pipeline pressure monitoring, and safety control of power plant boilers and hydraulic systems.

Key Performance Indicators

When selecting a pressure sensor, consider several key parameters. The range determines the pressure it can detect; accuracy reflects how closely the measurement result matches the true value; sensitivity affects the resolution of the output; and linearity reflects the intuitive relationship between the output and pressure. Furthermore, stability and response time directly impact its reliability under long-term use and rapidly changing conditions.