Abstract: A magnetic sensor that is inexpensive and suppresses changes in offset voltage caused by wear. The magnetic sensor includes magnetoresistance elements having electrical resistances that change in accordance with magnetism changes. The magnetic sensor detects magnetism based on changes in the electrical resistances. The magnetoresistance elements are covered by a protective film. Part of the protective film is etched and eliminated to form a recess.

Abstract: A method for manufacturing a semiconductor device that includes a housing, formed of a polyamide-series thermoplastic resin, and a semiconductor package sealed in the housing, which is formed of a thermosetting epoxy resin. The surface of the package is modified by UV-irradiation to have adhesive properties to polyamide. A plurality of connector terminals extend from the package and housing in parallel. A portion of the terminals is also sealed in the housing together with the package. Thus, the device is easily produced by insert molding and has excellent moisture resistance.

Abstract: A method for manufacturing a semiconductor device that includes a housing, formed of a polyamide-series thermoplastic resin, and a semiconductor package sealed in the housing, which is formed of a thermosetting epoxy resin. The surface of the package is modified by UV-irradiation to have adhesive properties to polyamide. A plurality of connector terminals extend from the package and housing in parallel. A portion of the terminals is also sealed in the housing together with the package. Thus, the device is easily produced by insert molding and has excellent moisture resistance.

Abstract: A magnetic sensor that prevents offset voltage from changing as time elapses. The magnetic sensor detects change in the direction of the magnetic field when the electric resistances of magnetic resistors change. The magnetic resistors of the magnetic sensor each include a heat treatment section formed by performing a pre-trimming heat treatment.

Abstract: A magnetic sensor that is inexpensive and suppresses changes in offset voltage caused by wear. The magnetic sensor includes magnetoresistance elements having electrical resistances that change in accordance with magnetism changes. The magnetic sensor detects magnetism based on changes in the electrical resistances. The magnetoresistance elements are covered by a protective film. Part of the protective film is etched and eliminated to form a recess.

Abstract: A magnetic sensor that prevents offset voltage from changing as time elapses. The magnetic sensor detects change in the direction of the magnetic field when the electric resistances of magnetic resistors change. The magnetic resistors of the magnetic sensor each include a heat treatment section formed by performing a pre-trimming heat treatment.

Abstract: A buckle device in which it can be detected whether or not a tongue plate inserted into a case is locked, and in which reliability of such detection is high. In the buckle device, a magnetic plate is provided at a leg portion which moves together with the tongue plate which is inserted into an interior of the case. Changes in orientation of a magnetic field of a magnet of a sensing section, which orientation varies due to the magnetic plate approaching and moving away from the magnet, are detected at an MRE sensor.

Abstract: A rotation detector resists magnetic disturbances from sources near the detector. The rotation detector includes a rotor on which iron magnetic path changing pieces are fixed at predetermined intervals. A first bias magnet and a first magneto-resistive element for detecting the flux of the first bias magnet oppose the magnetic path changing pieces. A magnetic guide plate is located to guide disturbing magnetic flux in predetermined directions. The disturbing magnetic flux thus fails to adversely affect the first magneto-resistive element.

Abstract: A semiconductor device includes a housing, which is formed of a polyamide-series thermoplastic resin, and semiconductor package sealed in the housing, which is formed of a thermosetting epoxy resin. The package has a modified face that is modified by UV-irradiation to have adhesive properties to polyamide. A plurality of connector terminals extend from the packages in parallel. A portion of the terminals is also sealed in the housing together with the package. Thus, the device is easily produced by insert molding and has excellent moisture resistance.

Abstract: A compact and inexpensive sensor sensitivity adjusting apparatus. The sensor sensitivity adjusting apparatus includes a sensor, a current supplying IC and a variable resistor. The current supplying IC has first and second fixed resistors connected in series between two terminals of a power supply, and an operational amplifier. The sensitivity of the sensor changes in accordance with the value of a drive current. The drive current is adjusted by changing the resistance of the variable resistor.

Abstract: A rotation detector includes a rotor having a shaft. Projections are located at predetermined intervals on the periphery of the rotor and extend in an axial direction. Magnets are located between the projections and the shaft. The flux of each magnet is detected by a corresponding magnetism detection element. Each magnetism detection element has magnetic resistors. Movement of the projections changes the direction of flux of the magnets. Each resistor is switched between a first state, in which its magnetic resistance is great, and a second state, in which its magnetic resistance is small, in accordance with the change of the flux direction. The resistors are divided into two groups. The groups are substantially symmetrical relative to a centerline of the groups such that, when the direction of the flux changes, the resistors in one group are in the opposite state from the resistors in the other group. The centerline of changes in the direction of the flux matches the centerline of the resistor groups.

Abstract: A position sensor has a magnet producing a magnetic field and a magnetic detector for detecting the magnetic field. The detector produces a resistance value variable according to the orientation of the magnetic field. The magnet and the magnetic detector are arranged to move relative to each other within a predetermined stroke so that the detector outputs a voltage signal with a predetermined waveform having a rate of change that prohibits the signal excessive of a predetermined value to return to the predetermined value.

Abstract: A buckle device in which it can be detected whether or not a tongue plate inserted into a case is locked, and in which reliability of such detection is high. In the buckle device, a magnetic plate is provided at a leg portion which moves together with the tongue plate which is inserted into an interior of the case. Changes in orientation of a magnetic field of a magnet of a sensing section, which orientation varies due to the magnetic plate approaching and moving away from the magnet, are detected at an MRE sensor.

Abstract: A rotation detector resists magnetic disturbances from sources near the detector. The rotation detector includes a rotor on which iron magnetic path changing pieces are fixed at predetermined intervals. A first bias magnet and a first magneto-resistive element for detecting the flux of the first bias magnet oppose the magnetic path changing pieces. A magnetic guide plate is located to guide disturbing magnetic flux in predetermined directions. The disturbing magnetic flux thus fails to adversely affect the first magneto-resistive element.

Abstract: A rotation detector that detects rotational position with high precision. The rotation detector includes a rotor having a shaft. Projections are located at predetermined intervals on the periphery of the rotor and extend in an axial direction. The rotation detector further includes magnets and magnetism detecting elements respectively detecting magnetism of the magnets. At least one of the magnets and the detecting elements are arranged between the projections and the shaft at predetermined intervals.

Abstract: An acceleration sensor (1) includes a parallelepiped case (2). A circuit board (3) is secured in the case (2). A sensor chip (5), on which a diffusion strain gauge (5b) is formed, is mounted on the circuit board (3). A cylindrical acceleration selecting element (13) is provided on the case (2). The axis of the acceleration selecting element (13) extends in the x direction. A cylindrical pressure transmitting element (14) is also provided on the case (2). The pressure transmitting element (14) communicates a hollowed part on the top of the sensor chip (5) with the interior of the acceleration selecting element (13). The hollowed part on the top of the sensor chip (5), the pressure transmitting element (14) and the acceleration selecting element (13) are filled with silicon gel (10).

Abstract: An accelerometer sensor is disclosed, utilizing a casing having a center axis, and a pressure sensitive element located at the bottom portion of the casing. A gel based medium is accommodated in the casing. Given that "x" denotes a positional deviation of the pressure sensitive element with respect to the center axis of the casing and that "h" denotes a height of the medium in the casing, the positional deviation (x) and the height (h) are set such that the value 2 x/h falls within a predetermined range and serves as a function of the anisotropic sensitivity ratio of the sensor.

Abstract: A motor drive circuit in which a first bipolar transistor is disposed between a ground terminal and one terminal of a motor, and a second bipolar transistor is disposed between the ground terminal and another terminal of the motor. Each of the transistors has a reverse breakdown voltage between an emitter and a collector which is greater than a voltage of a power source and has a reverse-direction h.sub.fe which is greater than or equal to a predetermined value. A resistor and a capacitor are disposed in parallel between respective bases of the first and second bipolar transistors and a ground terminal. Potential drawbacks can be prevented even when voltage of reverse polarity is supplied.