According to an aspect there is provided an apparatus comprising at least one electrode and a movable sensor membrane, wherein the apparatus comprises means for: measuring a voltage or a current; determining an amount of external pressure based on the measured voltage or current; based on the determined amount of external pressure, providing electrostatic feedback force such that the movable sensor membrane is undeflected; and determining a correlation between the electrostatic force feedback and the external pressure.

The present invention provides a MEMS pressure sensor and a manufacturing method. The pressure is formed by a top cap wafer, a MEMS wafer and a bottom cap wafer. The MEMS wafer comprises a frame and a membrane, the frame defining a cavity. The membrane is suspended by the frame over the cavity. The bottom cap wafer closes the cavity. The top cap wafer has a recess defining with the membrane a capacitance gap. The top cap wafer comprises a top cap electrode located over the membrane and forming, together with the membrane, a capacitor to detect a deflection of the membrane. Electrical contacts on the top cap wafer are connected to the top cap electrode. A vent extends from outside of the sensor into the cavity or the capacitance gap. The pressure sensor can include two cavities and two capacitance gaps to form a differential pressure sensor.

A method for producing a differential pressure sensor includes: a) Providing a sensor assembly; b) Providing a main body with a substantially rotationally symmetrical cavity for receiving the sensor assembly; c) Introducing the sensor assembly into the cavity of the main body; d) Welding the sensor assembly into the cavity of the main body by means of a resistance pulse welding method; e) Introducing, for example, by pressing in, a welding ring between the sensor assembly and the cavity of the main body in an opening region of the cavity; and f) Axial laser welding in the opening region of the cavity such that the main body is welded circumferentially to the sensor assembly by means of the welding ring.

A pressure sensor includes a diaphragm having a first principal surface and a second principal surface, a semiconductor chip in which resistors constituting a strain gauge are formed, a first structural body having one end coupled to a center of a second principal surface of the diaphragm and the other end coupled to the other surface of the semiconductor chip, and at least two second structural bodies disposed in two straight lines, orthogonal to each other, that pass through the center of the diaphragm in plan view so as to be disposed separately from the first structural body, and having one ends coupled to the second principal surface and the other ends coupled to the other surface of the semiconductor chip, in which the resistors are formed in regions between the first structural body and the second structural bodies in plan view in the semiconductor chip.

To suppress variations in the shift amount of the zero point of a sensor output when a pipe is connected to a pressure sensor via a clamp. A pressure sensor includes two semiconductor chips in two straight lines, orthogonal to each other, that pass through a center of a diaphragm in plan view, two resistors in the region between two supporting members supporting one semiconductor chip, and two other resistors in the region between two other supporting members supporting the other semiconductor chip.

A pressure sensor system with at least two absolute pressure sensors can have an external sensor with a pressure sensitive surface in contact with atmospheric pressure (proximal) and internal sensors each with a pressure sensitive surface in contact with one or more regions at an unknown pressure (distal). The unknown pressure is determined by a means to calculate the difference between the first sensor and the internal sensors.

A relative-pressure sensor determines the pressure of a medium in relation to an atmospheric pressure. The sensor includes a housing having a measuring element located in the housing, wherein the pressure to be measured acts upon an outer surface of the measuring element. The surface is in contact with the medium. The sensor also includes a reference-pressure supply, which supplies an inner surface of the measuring element with atmospheric pressure in the form of ambient air, and an evaluation unit, which determines the pressure of the medium from a variable determined using the measuring element. A drying chamber takes-up atmospheric humidity from the ambient air that is supplied via the reference-pressure supply. The drying chamber has a drying module comprising a container and a humidity-adsorbing material that is completely surrounded by the container.

The disclosed technology relates to a field serviceable pressure scanner suitable for high-pressure sensing applications and replacement of large pressure transmitter panels. The pressure scanner includes a housing having a mounting plate comprising a plurality of through-hole bores extending from a front to back side for mating with corresponding transducer ports of the pressure sensors, and a plurality of input ports disposed on the front side of the mounting plate and in communication with the corresponding plurality of through-hole bores. The pressure scanner assembly includes two or more field-replaceable (swappable) pressure sensors seal mounted to the back side of the mounting plate, each pressure sensor comprising one or more sensor ports, each of the one or more sensor port in communication with corresponding through-hole bores in the mounting plate, and a multi-channel data acquisition system configured to receive pressure signals from the two or more field-replaceable pressure sensors.

A differential MEMS pressure sensor includes a topping wafer with a top side and a bottom side, a diaphragm wafer having a top side connected to the bottom side of the topping wafer and a bottom side, and a backing wafer having a top side connected to the bottom side of the diaphragm wafer and a bottom side. The topping wafer includes a first cavity formed in the bottom side of the topping wafer. The diaphragm wafer includes a diaphragm, a second cavity formed in the bottom side of the diaphragm wafer underneath the diaphragm, an outer portion surrounding the diaphragm, and a trench formed in the top side of the diaphragm wafer and positioned in the outer portion surrounding the diaphragm.

An oil-fill pressure transducer including a flexible member configured to protect an isolation diaphragm and sensing element. The pressure transducer includes a sensing element mounted to the header, an isolation diaphragm mounted on the front side of the header, and adjacent to the sensing element such that an oil-fill cavity is defined between the sensing element and the isolation diaphragm. The flexible member is disposed adjacent to the isolation diaphragm and a retention member is disposed adjacent to the flexible member. A cavity in communication with the retention member is configured to transmit pressure media to the isolation diaphragm via the flexible member. The flexible member can include thru-holes. The flexible member may compress under an applied positive pressure change. The flexible member may temporarily separate from at least a portion of the isolation diaphragm under an applied negative pressure change.