2264results about "Magnetic field measurement using galvano-magnetic devices" patented technology

A sensor assembly includes a first magneto-resistive field sensor in a first surface-mountable package, which measures first and second components of a magnetic field projected onto respective different first and second axes with respect to a spatial orientation of the sensor and to produce first position signals indicative of the measured first and second components. A second magneto-resistive field sensor in a second surface-mountable package measures at least a third component of the magnetic field projected onto at least a third axis with respect to the spatial orientation of the sensor, and to produce second position signals indicative of the measured third component. A substrate assembly orients the first field sensor in a first spatial orientation and to orient the second field sensor in a second spatial orientation so that the third axis is oriented out of a plane containing the first and second axes.

A fabrication process for a tunneling magnetoresistance (TMR) sensor is disclosed. In particular, a unique method of forming a barrier layer of the TMR sensor is utilized so that the TMR sensor exhibits good magnetic and TMR properties. In one particular example, the barrier layer is formed by depositing a metallic film in an argon gas in a DC magnetron sputtering module, depositing an oxygen-doped metallic film in mixed xenon and oxygen gases in an ion-beam sputtering module, and oxidizing these films in an oxygen gas in an oxygen treatment module. This three-step barrier layer formation process minimizes oxygen penetration into ferromagnetic (FM) sense and pinned layers of the TMR sensor and optimally controls oxygen doping into the barrier layer. As a result, the FM sense and pinned layers exhibit controlled magnetic properties, the barrier layer provides a low junction resistance-area product, and the TMR sensor exhibits a high TMR coefficient.

A magnetic field sensor apparatus includes a first magnetic field sensor and a second magnetic field sensor, arranged on a substrate in a spaced manner from each other, a first temperature sensor with an output for a first temperature sensor signal, a second temperature sensor with an output for a second temperature sensor signal, a first stress sensor with an output for a first stress sensor signal, and a second stress sensor with an output for a second stress sensor signal, wherein the first temperature sensor and the first stress sensor are arranged more closely to the first magnetic field sensor or at a location identical with the first magnetic field sensor, and the second temperature sensor and the second stress sensor are arranged more closely to the second magnetic field sensor than to the first magnetic field sensor or at a location identical with the second magnetic field sensor.

An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and substrate having a first surface in which is disposed one or more magnetic field transducers, with the first surface being proximate the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit relative to a conventional orientation. A current conductor portion can be deposited proximate to a surface of the substrate and proximate to the one or more magnetic field sensors. With this arrangement, a current sensor is provided for which the one or more magnetic field transducers are very close to the current conductor portion, resulting in a current sensor having improved sensitivity. An insulating layer can be disposed between the current conductor portion and the substrate.

The present invention involves a method and apparatus for canceling the effects of magnetic field noise in a torque sensor by placing three sets of magnetic field sensors around a shaft, the first set of field sensors being placed in the central region of the shaft and the second and third sets of field sensors being placed on the right side and left side of the field sensors placed at the central region, respectively. A torque-induced magnetic field is not cancelled with this arrangement of field sensors but a magnetic near field from a near field source is cancelled.

The magnetic sensor is fabricated such that a magnetic sensor chip, having a one-chip structure in which MRE bridges and a comparator are included, is mounted onto a lead frame using an adhesive material, and then the magnetic sensor chip mounted on the lead frame is encapsulated by molding in a molded material. The magnetic sensor includes a magnetic-field generating portion formed by magnetizing at least one of the chip mounting member, the adhesive material, and the encapsulating material.