Absolute Pressure Sensor

An absolute pressure sensor is a sealed system that functions by referencing a perfect vacuum, so it produces pressure readings that do not include the effect of atmospheric pressure. In practice, absolute piezoresistive pressure sensors measure the pressure relative to a high vacuum reference sealed behind its sensing diaphragm. The vacuum has to be negligible compared to the pressure to be measured. The deformation of the diaphragm is not impacted by atmospheric pressure because it uses the sealed vacuum as its reference and zero point.

Instrument manufacturers developed absolute pressure sensors for applications that require readings not influenced by changes in altitude or weather, such as in meteorological and aviation applications.