Method of pressure sensing with a pressure sensor having a sensor membrane and a compensation membrane

Abstract

The invention provides for a method of sensing pressure with a pressure sensor having a sensor membrane and a compensation membrane. The pressure sensor also includes a power supply, a controller; and a charge amplifier, a charge injector and two switches arranged in signal communication with the controller. The method includes the step of connecting the charge amplifier to the switches via a sensor capacitor Cs in parallel with a reference capacitor Cr in parallel with a parasitic capacitance Cp to ground, the charge injector and charge amplifier arranged in parallel connection between the capacitors and the controller. The method also includes the step of operating the switches, via the controller, to determine a charge imbalance indicative of a pressure difference between the sensor and compensation membranes.

Dependencies are inferred from the claim text.