US Patent 7089797 Temperature insensitive pressure sensor

A pressure sensor that compensates for variations in temperature by having first (53) and second (51) chambers with first and second respective flexible membranes. The first and second flexible membranes deflect in response to pressure differences within the first and second chambers respectively. The first membrane is exposed to the fluid pressure (66) to be measured, such as the air pressure in a tire. The second membrane sealed from the fluid pressure, and, associated circuitry converts the deflection of the first flexible membrane into an output signal related to the fluid pressure, and converts the deflection of the second membrane into an adjustment of the output signal to compensate for the temperature of the sensor.