Certain implementations of the disclosed technology may include systems, methods, and apparatus for a sealed transducer with an adjustment port. The sealed transducer may include one or more terminals. A first terminal may include electrical connections for connecting to an input voltage source, a ground, and for providing a transducer output signal. A second terminal, for example, may include an electrical port for connecting to an external and separately sealed adjustment network. In one example implementation, the adjustment network can include one or more components configured to couple with internal circuitry of the transducer to alter a response of the transducer.

Apparatus and associated methods relate to sensing a physical parameter and verifying correct operation of a system used to sense the physical parameter. A sensing device includes four resistive elements configured in a Wheatstone bridge configuration is configured to sense the physical parameter. A biasing network selectively provides first and second biasing conditions to the sensing device. First and second output electrical signals are generated by the sensing device in response to the first and second biasing conditions, respectively, selectively provided to the sensing device. The first and second output electrical signals are each indicative of the parameter value of the physical parameter, but not necessarily equal to one another. A verification module verifies correct operation of the system based on a consistency determination of first and second output electrical signals.

A method for testing the tightness of a housing involves providing a pressure sensor in a housing, sealing the housing, and detecting a pressure level in the housing.

A pressure sensor includes a diaphragm that flexurally deforms when pressurized, a plurality of piezoresistive elements provided in the diaphragm, and a plurality of temperature-sensitive elements provided in the diaphragm in correspondence with the plurality of piezoresistive elements, wherein a separation distance between the piezoresistive element and the temperature-sensitive element corresponding to each other is shorter than a separation distance between the piezoresistive element and the temperature-sensitive element not corresponding to each other. Further, each of the temperature-sensitive elements is provided to at least partially overlap with the corresponding piezoresistive element in a plan view of the diaphragm.

A sensor drive circuit for driving a sensor with a current includes a first current source configured to generate a first current having a temperature characteristic of which a first order coefficient is positive and of which a second order coefficient is negative. The sensor drive circuit includes a second current source configured to generate a second current having a temperature characteristic of which a first order coefficient is negative and of which a second order coefficient is negative. The sensor drive circuit includes a current amplifier configured to amplify a third current, the third current being set by adding the first current and the second current. The sensor drive circuit includes a constant current source configured to generate a temperature-corrected constant current, such that a drive current for the sensor is set by adding the constant current to the amplified third current.

A sensor includes a plurality of piezoresistive elements and a plurality of electrical connection terminals. The plurality of piezoresistive elements are fabricated on a first side of a substrate. A second side of the substrate is configured to be coupled to an object where a physical disturbance is to be detected. A plurality of electrical connection terminals are coupled to the first side of the substrate.

A pressure sensor includes a Wheatstone bridge circuit including a first resistor, a second resistor, a third resistor, and a fourth resistor having matching output characteristics. The pressure sensor further includes a first trim resistor in series with the Wheatstone bridge circuit, wherein the first trim resistor has output characteristics matching the output characteristics of the first resistor, the second resistor, the third resistor, and the fourth resistor of the Wheatstone bridge. The pressure sensor additionally includes a second trim resistor in parallel or a parallel loop with the Wheatstone bridge circuit, wherein the second trim resistor has output characteristics matching the output characteristics of the first resistor, the second resistor, the third resistor, and the fourth resistor of the Wheatstone bridge.

A pressure sensor die especially suitable for high-temperature, high-pressure operating environment and delivering accurate and reliable pressure measurement at low cost. A single crystalline silicon includes a cap, a substrate and a base connected together. A recess formed on the cap creates an upper sealed cavity with the substrate. A silicon oxide layer is formed between the substrate and the cap. A recess formed on the base creates a lower sealed cavity with the substrate. The upper sealed cavity and the lower sealed cavity overlap in their projections. The substrate includes at least two sets of piezoresistive sensing elements located within the overlapping projections, perpendicular to each other, and oriented in different crystallographic directions.

The invention relates to a MEMS sensor, including a deflectably situated functional layer, a conversion device for converting a deflection of the functional layer into an electrical signal, the conversion device including at least one electrical element, the at least one electrical element being at least partially electrically connected to a first area, and the first area being at least partially electrically connected to a second area, and the first and second areas and/or the first area and the at least one electrical element being electrically operable in a reverse direction and a forward direction, and a control unit, the control unit being designed to at least partially operate the at least one electrical element and the first area and/or the first area and the second area in the forward direction to provide thermal energy.

A pressure sensor includes a Wheatstone bridge and a heat emitting diode. The Wheatstone bridge includes a first resistor, a second resistor, a third resistor, and a fourth resistor. The first resistor, the second resistor, the third resistor, and the fourth resistor are coupled to form a loop, the first resistor, the second resistor, and the third resistor are fixed resistors, and the fourth resistor is a varistor. A first output terminal of the Wheatstone bridge is coupled to a first terminal of the heat emitting diode, and a second output terminal of the Wheatstone bridge and a second terminal of the heat emitting diode are configured to output an electrical signal.