Abstract:
The contactless magnetic sensor consists of at least one excitation coil (10) connected to the source (20) of alternating signal. In thejcavity of the excitation coil (10) is located a magnetic field sensor (40) and its output is connected to the input of the amplifier (60). The sensor includes an excitation modulator (21), which is connected to the source (20). Output of the amplifier (60) is connected to the input of a low-pass filter (80), to the input of a band-pass filter (81), and to the input of a high-pass filter (82). The source (20) generates alternating, advantageously rectangular-shaped current, which generates an alternating current magnetic field around the excitation coil (10) that interacts with materials in the excitation coil (10) vicinity. The magnetic field sensor (40) may be an anisotropic magnetoresistor AMR or a Hall probe. In case of an AMR sensor the excitation signal of the excitation coil (10) is connected via the separating capacitor (30) directly to the flipping input of the AMR sensor coil. Since the excitation signal of the excitation coil (10), and therefore the generated magnetic field are in-phase, and the magnetic field sensor's output is modulated by the flipping circuit, the result is a controlled rectification of the sensor's output signal and self-demodulation of the output signal. The output of the sensor may therefore be used for position detection, proximity detection or discrimination of materials in the coil vicinity.
Abstract:
Novel anisotropic magneto-resistive (AMR) sensor architectures and techniques for fabricating same are described. In some embodiments, AMR sensors (50) having barber pole structures (36a, 36b, 36c, 36d, 36e) disposed below corresponding AMR sensing elements (40) are provided. AMR sensors having segmented AMR sensing elements are also described. Fabrication techniques that can be used to fabricate such sensors are also described. Fabrication techniques are also described that can reduce the risk of contamination during AMR sensor fabrication.
Abstract:
An apparatus includes circuits, a field line configured to generate a magnetic field based on an input, a sensing module configured to determine a parameter of each circuit, and a magnetic field direction determination module configured to determine an angular orientation of the apparatus relative to an external magnetic field based on the parameter. Each circuit includes multiple magnetic tunnel junctions. Each magnetic tunnel junction includes a storage layer having a storage magnetization direction and a sense layer having a sense magnetization direction configured based on the magnetic field. Each magnetic tunnel junction is configured such that the sense magnetization direction and a resistance of the magnetic tunnel junction vary based on the external magnetic field. The parameter varies based on the resistances of the multiple magnetic tunnel junctions. The magnetic field direction determination module is implemented in at least one of a memory or a processing device.
Abstract:
Magnetic field sensor designs that provide both increased directionality and proximate coupling desirable for improved directionality and sensitivity and methods for fabricating them.
Abstract:
The invention relates to an electronically commutated electric motor. The electronically commutated electric motor comprises a stator and a rotor, which in particular is designed to be permanently magnetic. The electric motor also comprises a rotor position sensor, wherein the rotor position sensor is designed to detect a predetermined number of, in particular discrete, rotor positions along a rotational direction of the rotor. The rotor position sensor is also designed to generate a sensor signal representing the rotor positions. The electric motor also comprises a control unit connected to the rotor position sensor, wherein the control unit is designed to actuate the stator in order to generate a magnetic rotary field in dependence on the sensor signal. According to the invention, the control unit comprises an input for a steering angle signal, in particular an analog or digital steering angle signal, which represents a steering angle of a vehicle steering system. The control unit is designed to additionally actuate the stator depending on the steering angle signal.
Abstract:
The present invention relates to a magnetic field sensing device (50) comprising several functionally different layers (38, 60, 70), wherein a Wheatstone bridge layer (70) comprises at least two resistors (20) of a Wheatstone bridge (18), each resistor (20) comprises at least one magnetic field sensing element (10) in the form of a resistor subelement (22), and a flip conductor layer (38) comprising at least one flip conductor (30) for flipping the internal magnetization state of each magnetic field sensing element (10). The flip conductor (30) comprises a plurality of conductor stripes (32) being arranged on at least two different flip conductor sublayers (38-1, 38-2) of said flip conductor layer (38) and being electrically coupled with each other through vias. The multilayer arrangement of said flip conductor (30) provides a compact design of said magnetic field sensing device (50), such that a decreased power consumption, decreased inductance and improved sensitivity of the magnetic field sensing device can be achieved.
Abstract:
Devices (1) comprising sensor arrangements (10) with field detectors (12) for detecting components (18) of magnetic fields in planes of the field detectors (12) and with movable objects (13) for, in response to tilting movements, changing at least parts of the components (18) of the magnetic fields in the plane; of the field detectors (12) are made less sensitive to in-plane stray fields by providing the fold detectors (12) with saturated field-dependent elements (31). The movable object (13) 1 nay comprise a movable field generator for generating the magnetic field, or the movable of object (13) and the field generator (11) may be different objects. The magnetic field is such that the field-dependent element (31) is saturated. The field generator (11) is smaller than the field detector (12), and the movable object (13) is larger than the field detector (12), to reduce alignment problems. The movable object (13) has a pivoting point close to the field detector (12).