Patent ID: 7021151

Claim:
A pressure sensing system formed in a monolithic semiconductor substrate, the pressure sensing system comprising: at least one enclosed cavity pressure sensing device formed on the monolithic semiconductor substrate, the at least one enclosed cavity pressure sensing device adapted to be disposed in an environment for developing an electrical pressure signal corresponding to the pressure in the environment; at least one leaking cavity pressure device formed on the monolithic semiconductor substrate, the at least one leaking cavity pressure sensing device adapted to be disposed in the environment for developing a reference pressure signal; differential circuitry formed in the monolithic semiconductor substrate and coupled to receive the electrical pressure signal from the enclosed cavity pressure sensing device and the reference pressure signal from the leaking cavity pressure sensing device and to generate an input electrical pressure signal; driver circuitry formed in the monolithic semiconductor substrate, the driver circuitry being responsive to input electrical pressure signals for generating an output pressure signal; and a conductive interconnect structure formed in the monolithic semiconductor substrate, the conductive interconnect structure being connected between the enclosed cavity pressure sensing device and the leaking cavity pressure sensing device and the differential circuitry and the driver circuitry.