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.

A sensor apparatus includes: a sensor that includes a resistor bridge circuit; a temperature detection circuit that provides a first path and a second path; a voltage measurement portion that measures a voltage of each of the differential output terminals; a controller that causes the voltage measurement portion to measure the voltage of each of the two differential output terminals; and a calculator that calculates a difference between the voltages of the two differential output terminals to acquire temperature information of the sensor.

A sensor system includes a plurality of strain gauges and a passive compensation circuit. The plurality of strain gauges are configured to provide an output voltage indicative of a sensed pressure using an input voltage. The passive compensation circuit that includes a span resistor, first and second compensation resistors, and a zero offset resistor. The span resistor is connected between an input voltage and the pressure sensor and is configured to control a range of an output voltage for a pressure range of the pressure sensor. The first and second compensation resistors are operatively connected in parallel with the pressure sensor and are configured to control current provided to the pressure sensor. The zero offset resistor is operatively connected between the first and second compensation resistors and the pressure sensor and is configured to control a base value of the output voltage for zero pressure.

A semiconductor differential pressure sensor includes a pressure detection element, which is arranged such that its main surface is fixed on a top of a first protrusion with an adhesive while a second protrusion is fitted into its opening. Thus, the pressure detection element is held with high holding power at an exact position. Moreover, the adhesive does not flow into a first pressure introducing path, whereby blocking of the first pressure introducing path is prevented. Furthermore, by providing a recess around the first protrusion, influence of thermal deformation of a resin package on pressure detection characteristics is decreased.

A sensor driving device drives a sensor circuit formed of a Wheatstone bridge, which is connected between a main power supply for supplying a power supply potential and a reference power supply for supplying a reference potential lower than the power supply potential and includes at least one gauge resistor varying a resistance value thereof with deformation caused by external force. The sensor driving device includes a first resistor, which is connected in series with the sensor circuit between the main power supply and the sensor circuit, and a second resistor, which is connected between the sensor circuit and the reference power supply. The sensor driving device further includes a temperature output circuit connected in parallel to the sensor circuit relative to the main power supply. The temperature output circuit includes two output terminals, which output a potential difference smaller than a potential difference between one end of a main power supply side and one end of a reference power supply side.

Compensated pressure sensor includes a MEMS pressure sensor die having resistors RA and RD connected in series in a first leg of a Wheatstone bridge and resistors RB and RC connected in series in a second leg of the Wheatstone bridge; a first and second fuse; and a first, second, third, fourth, fifth and sixth resistor; wherein: a first end of the first resistor is connected in series with the first leg of the bridge and a first end of the second resistor is connected in series with the second leg of the bridge; the first fuse is connected, at a first end, to a first output of the bridge, and at a second end, to a second end of the third resistor and to a first end of the second fuse; the second fuse is connected, at a second end, to a second output of the bridge; a first end of the third resistor is connected to an input to the bridge and to a first end of the fourth resistor; a second end of the fourth resistor is connected to a second end of the first resistor, a second end of the second resistor and a first end of the sixth resistor; and the fifth resistor is connected, at a first end, to the input to the bridge.

A sensor element that has high measurement precision by providing a resistance-change length ratio corresponding to a direction-specific extension length is provided. The sensor element includes an element body disposed in a sensor body to measure a temperature and a pressure and having a diaphragm deformed based on the temperature or the pressure. Additionally, the sensor element includes pressure-measuring resistors including a second resistor portion and a fourth resistor portion disposed along a diametric direction with respect to a center of an upper surface of the diaphragm and in an extension section on the upper surface of the diaphragm and a first resistor portion and including a third resistor portion disposed outside the second resistor portion or the fourth resistor portion in a compression section on the upper surface of the diaphragm to eliminate a resistance change caused by a pressure-specific temperature change.

A physical quantity detector includes: a bridge circuit portion that includes a bridge circuit including a first, second, third, and fourth strain gauges each having a resistance value that changes in response to an application of a physical quantity and to temperature, the bridge circuit portion outputting, as a first detection signal, a first voltage, and outputting, as a second detection signal, a second voltage; a temperature characteristic adjustment portion that is connected in parallel to the bridge circuit portion, and outputs, as a third detection signal, a third voltage corresponding to the input voltage; a first signal processing circuit portion that receives the first and second detection signals, and outputs a first differential voltage; and a second signal processing circuit portion that receives the second and third detection signals, and outputs a second differential voltage.

The present disclosure provides a device for monitoring oil pressure in an oil cylinder of a diaphragm compressor, including a piston rod and a strain gauge circuit. The strain gauge circuit includes a strain gauge component and a bridge circuit connected, and the strain gauge component is arranged on the surface of the piston rod. A strain gauge component is noninvasively arranged on the piston rod of the diaphragm compressor to measure the load of the piston rod, such that the oil pressure can be measured indirectly, and thus the oil pressure of the diaphragm compressor can be measured nondestructively. Nondestructive and noninvasive monitoring of the diaphragm compressor is safe and reliable, and can achieve accurate monitoring of the oil pressure especially in high-pressure working conditions.

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 sensor.