Pressure sensor with conductive laminate membrane

Abstract

A pressure sensor (30) for sensing a fluid pressure in harsh environments such as the air pressure in a tire, by using a chamber (58) partially defined by a flexible membrane (50), the flexible membrane (50) is a laminate having at least two layers wherein at least one of the layers is at least partially formed from conductive material, and the chamber (58) containing a fluid at a reference pressure, such that the flexible membrane (50) deflects from any pressure difference between the reference pressure and the fluid pressure; and, associated circuitry (34) for converting deflection of the flexible membrane (50) into an output signal indicative of the fluid pressure. Forming the membrane from a number of separately deposited layers alleviates internal stress in the membrane (50). The layers can be different materials specifically selected to withstand harsh environments.

Dependencies are inferred from the claim text.