pressuresensing

Pressure sensing refers to devices and methods that measure the pressure of liquids or gases and convert it into an electrical, optical, or mechanical signal that can be read by instrumentation. The sensing element typically experiences a mechanical deflection, a change in capacitance, or a change in an optically detectable property when subjected to pressure.

Common transduction principles include piezoresistive (resistance changes in a stressed diaphragm; widely used in MEMS), capacitive (diaphragm deflection changes capacitance; high sensitivity and low power), piezoelectric (charges generated by pressure; effective for dynamic pressure), and optical (fiber Bragg gratings or interferometric sensors that translate strain into wavelength or intensity changes).

Pressure sensors are categorized by reference pressure as absolute (relative to vacuum), gauge (relative to atmospheric pressure), and differential (measures the difference between two ports). Form factors range from bulk industrial devices to microelectromechanical systems (MEMS) used in consumer electronics and automotive applications, including rugged, high-volume packages and miniature, low-power sensors.

Performance metrics include range, sensitivity, linearity, hysteresis, accuracy, resolution, temperature dependence, response time, and repeatability. Most devices incorporate temperature compensation and calibration to mitigate drift and aging effects.

Applications span automotive (tire and manifold pressure), aerospace, industrial process control, HVAC, medical devices (invasive and noninvasive monitoring), and consumer electronics (barometers and fluid-monitoring sensors). Limitations can include sensitivity to temperature changes, long-term drift, mechanical shock, material compatibility with media, and packaging-induced errors.