Methods of compensating for undesired influences in a pressure transmitter wherein the pressure transmitter comprises a body for housing a low-pressure sensor and a high-pressure sensor each of which is in fluid communication with a port and in further fluid communication with each other through a connector tube containing a fill fluid. Various embodiments of the compensation process use one of the high-pressure and the low-pressure sensor as a common reference, compensating for changes in calibration, such as changes in the effective areas or spring rates of the non-reference sensor.

A security system for a building comprises a pressure sensor and a computer system communicatively coupled with the pressure system. The pressure sensor coupled to a movable portion of a window in the building. The computer system is configured to: receive a first pressure measurement from the pressure sensor; compare the first pressure measurement to a reference pressure measurement; and based on the comparison, detect that the movable portion of the window has moved.

A security system for a building comprises a pressure sensor and a computer system communicatively coupled with the pressure system. The pressure sensor coupled to a movable portion of a window in the building. The computer system is configured to: receive a first pressure measurement from the pressure sensor; compare the first pressure measurement to a reference pressure measurement; and based on the comparison, detect that the movable portion of the window has moved.

Disclosed is a method of processing a periodic voltage signal, called the input signal, relating to the pressure existing in a combustion chamber of a cylinder of an internal combustion engine. The method includes a step (E6) of determining a second instant of unlocking of the base signal during a second peak phase, a step (E7) of determining a second instant of locking, which is subsequent to the second instant of unlocking and for which the input signal is in the plateau phase consecutive to the second peak phase, and a step (E8) of generating a base signal between the second instant of unlocking and the second instant of locking on the basis of a slope value of a straight line determined during a first peak phase between a first instant of unlocking and a first instant of locking.

Disclosed is a method of processing a periodic voltage signal, called the input signal, relating to the pressure existing in a combustion chamber of a cylinder of an internal combustion engine. The method includes a step (E6) of determining a second instant of unlocking of the base signal during a second peak phase, a step (E7) of determining a second instant of locking, which is subsequent to the second instant of unlocking and for which the input signal is in the plateau phase consecutive to the second peak phase, and a step (E8) of generating a base signal between the second instant of unlocking and the second instant of locking on the basis of a slope value of a straight line determined during a first peak phase between a first instant of unlocking and a first instant of locking.

Disclosed is an apparatus which has, among other things, a MEMS device with a first measurement arrangement for capturing a measurement variable (X.sub.1) based on a physical variable, which has a useful variable component (N.sub.1) and a first disturbance variable component (Z.sub.1), and a second measurement arrangement for capturing a second disturbance variable component (Z.sub.2). The apparatus furthermore has a disturbance compensation circuit which is configured to combine the second disturbance variable component (Z.sub.2) and the measurement variable (X.sub.1) with one another and to obtain a disturbance-compensated measurement variable (X.sub.comp). The MEMS device is arranged in a housing, wherein the MEMS device is in immediate mechanical contact with the housing by way of at least 50% of a MEMS device surface.

A differential pressure sensor may provide a common mode corrected differential pressure reading. The differential pressure sensor may include two pressure sensing diaphragms. The pressure sensor may be configured so that the first diaphragm measures the differential pressure between two sections of a fluid. The pressure sensor may also be configured so that the second diaphragm measures the common mode error experienced by the die at the time the differential pressure is read by the first diaphragm. Electrical connectors may be configured so that the differential pressure outputs a common mode error corrected differential pressure reading based on the readings of the first and second diaphragm.

In accordance with an embodiment, a MEMS sensor includes a MEMS arrangement having a movable electrode and a stator electrode arranged opposite the movable electrode. The MEMS sensor includes a first bias voltage source, which is connected to the stator electrode and which is configured to apply a first bias voltage to the stator electrode. The MEMS sensor further includes a common-mode read-out circuit connected to the stator electrode by a capacitive coupling and comprising a second bias voltage source, which is configured to apply a second bias voltage to a side of the capacitive coupling that faces away from the stator electrode.

The present invention makes it possible to, even when a stainless steel is adopted in a diaphragm: prevent the diaphragm and a strain sensor from exfoliating from each other; be hardly susceptible to the influence of temperature in an operating environment; not allow the sensitivity of a pressure sensor to be dominated only by the mechanical characteristic of a material constituting the diaphragm; and increase the degree of freedom in design of members constituting the pressure sensor. A pressure sensor according to the present invention is, in order to solve the above problems, characterized in that: the pressure sensor has a diaphragm deforming by the pressure of a fluid, an elastic body covering the whole surface of the diaphragm and joining to the diaphragm on one side, and a strain sensor being arranged by joining on the other side of the elastic body and on an end side apart from a position corresponding to the center of the diaphragm and detecting the deformation of the elastic body working together with the deformation of the diaphragm as a strain; and the elastic body is formed of a material having a linear expansion coefficient close to the linear expansion coefficient of a material constituting the strain sensor.

The present invention makes it possible to, even when a stainless steel is adopted in a diaphragm: prevent the diaphragm and a strain sensor from exfoliating from each other; be hardly susceptible to the influence of temperature in an operating environment; not allow the sensitivity of a pressure sensor to be dominated only by the mechanical characteristic of a material constituting the diaphragm; and increase the degree of freedom in design of members constituting the pressure sensor. A pressure sensor according to the present invention is, in order to solve the above problems, characterized in that: the pressure sensor has a diaphragm deforming by the pressure of a fluid, an elastic body covering the whole surface of the diaphragm and joining to the diaphragm on one side, and a strain sensor being arranged by joining on the other side of the elastic body and on an end side apart from a position corresponding to the center of the diaphragm and detecting the deformation of the elastic body working together with the deformation of the diaphragm as a strain; and the elastic body is formed of a material having a linear expansion coefficient close to the linear expansion coefficient of a material constituting the strain sensor.