A basic resistive pressure sensor, also known as a piezoresistive pressure sensor, is a type of transducer used to measure pressure by changing its electrical resistance in response to applied pressure. The key function of a resistive pressure sensor is to convert mechanical pressure into an electrical signal that can be easily measured and interpreted.
The basic working principle of a resistive pressure sensor involves a thin diaphragm made of a resistive material, such as silicon, bonded to a rigid base. When pressure is applied to the diaphragm, it undergoes deflection, causing a change in its dimensions and resulting in a change in the electrical resistance of the resistive material. The resistance of the material increases or decreases proportionally to the applied pressure.
Typically, the resistive pressure sensor is part of a Wheatstone bridge circuit. The Wheatstone bridge is a network of four resistive arms, where the resistive pressure sensor replaces one of the arms. The output voltage of the Wheatstone bridge changes with the applied pressure, and this voltage can be measured and calibrated to determine the pressure value accurately.
The electrical output of the resistive pressure sensor can be connected to various electronic devices, such as microcontrollers, analog-to-digital converters (ADCs), or signal conditioning circuits. These devices can then process the output signal and display the pressure measurement or transmit it to other systems for further analysis or control purposes.
Resistive pressure sensors are commonly used in a wide range of applications, including automotive systems (e.g., tire pressure monitoring), industrial automation, consumer electronics (e.g., smart devices with pressure sensing capabilities), medical devices, and aerospace applications, among others, due to their simplicity, reliability, and cost-effectiveness.