Gauge pressure sensor is a sensor used to measure pressure values ​​relative to the ambient atmospheric pressure. It converts the difference between the measured pressure and atmospheric pressure into an electrical signal digital output.In terms of structure, the digital gauge pressure sensor has a vent that allows atmospheric pressure to enter the chip and contact one side of the sensing element, while the other side is connected to the measured pressure. The output method is the same as that of the digital absolute pressure sensor, using I²C/SPI, and the output is a calibrated pressure value without the need for an external ADC or compensation circuit.