Abstract: In a combustion pressure sensor having built-in charge amplifier, signal line overheating and deterioration of detection accuracy is restricted. The combustion pressure sensor includes a sensor body that includes a piezoelectric element having one end connected to chassis ground through a housing and detects pressure in a combustion chamber of engine, and a charge amplifier that includes at least a voltage converting unit converting output of the sensor body into voltage signal and a reference voltage generating unit generating reference voltage supplied to the voltage converting unit and operates on power supplied from a signal processing unit disposed outside. The reference voltage generating unit includes a voltage generating circuit having a constant current circuit and a resistor connected in series. The voltage generating circuit has one end connected to power line extending from the signal processing unit, and the other end connected to the end of the piezoelectric element.

Abstract: In a combustion pressure sensor having built-in charge amplifier, signal line overheating and deterioration of detection accuracy is restricted. The combustion pressure sensor includes a sensor body that includes a piezoelectric element having one end connected to chassis ground through a housing and detects pressure in a combustion chamber of engine, and a charge amplifier that includes at least a voltage converting unit converting output of the sensor body into voltage signal and a reference voltage generating unit generating reference voltage supplied to the voltage converting unit and operates on power supplied from a signal processing unit disposed outside. The reference voltage generating unit includes a voltage generating circuit having a constant current circuit and a resistor connected in series. The voltage generating circuit has one end connected to power line extending from the signal processing unit, and the other end connected to the end of the piezoelectric element.

Abstract: An antenna unit having an antenna coil pattern is disposed in a casing. A sensor unit has a surface acoustic wave detecting element including a first sensing electrode that generates and receives a surface acoustic wave and a first reflector that reflects the surface acoustic wave, which are provided on a substrate configured of a piezoelectric material, and a sensor coil pattern electrically connected to the first sensing electrode and coupled to the antenna coil pattern. The sensor unit is disposed in a pressure receiving portion, and a signal is transmitted between the sensor unit and the antenna unit by wireless communication resulting from a coil coupling.

Abstract: A pressure sensor is disclosed. The pressure sensor comprises a sensor chip having a depressed portion and a diaphragm defining a bottom of the depressed portion, a support member defining a pressure transmission passage communicating with the depressed portion, and a gel member continuously filling the depressed portion and at least a part of the pressure transmission passage. The sensor chip is bonded to a mounting surface of the support member with an adhesive. An edge of an open end of the pressure transmission passage on the mounting surface faces an surrounding region of the depressed portion of the sensor chip.

Abstract: A semiconductor physical quantity sensor includes a sensor chip, a support member for fixing the sensor chip to a fixing position and an adhesive bonding the sensor chip with the support member. The sensor chip includes a semiconductor substrate and a chip base supporting the semiconductor substrate. The semiconductor substrate is provided with a sensing portion for detecting a physical quantity. The chip base is bonded with the support member through the adhesive. The adhesive is provided by a mixture of an adhesive base material mainly made of a resin and a granular material mainly made of a cross-linked resin.

Abstract: A pressure sensor is disclosed. The pressure sensor comprises a sensor chip having a depressed portion and a diaphragm defining a bottom of the depressed portion, a support member defining a pressure transmission passage communicating with the depressed portion, and a gel member continuously filling the depressed portion and at least a part of the pressure transmission passage. The sensor chip is bonded to a mounting surface of the support member with an adhesive. An edge of an open end of the pressure transmission passage on the mounting surface faces an surrounding region of the depressed portion of the sensor chip.

Abstract: A semiconductor physical quantity sensor includes a sensor chip, a support member for fixing the sensor chip to a fixing position and an adhesive bonding the sensor chip with the support member. The sensor chip includes a semiconductor substrate and a chip base supporting the semiconductor substrate. The semiconductor substrate is provided with a sensing portion for detecting a physical quantity. The chip base is bonded with the support member through the adhesive. The adhesive is provided by a mixture of an adhesive base material mainly made of a resin and a granular material mainly made of a cross-linked resin.