Patent classifications
G01R33/0082
MAGNETIC FIELD SENSOR AND APPARATUS FOR MEASURING MAGNETIC FIELD
A magnetic field sensor of the present invention includes a first electrode including a magnetic material, a second electrode including a non-magnetic material, a common electrode disposed between the first electrode and the second electrode and connected to a ground terminal, a power supplier of which one end is connected to the first electrode and the second electrode and of which another end is connected to the common electrode to supply power of a frequency band required, a variable resistor configured to control at least one of a resistance value between the first electrode and the power supplier or a resistance value between the second electrode and the power supplier, and a differential amplifier connected to the first electrode through a positive terminal and connected to the second electrode through a negative terminal to output a difference value between a first capacitance generated by the first electrode and a second capacitance generated by the second electrode in response to external application of a magnetic field.
MAGNETIC RESONANCE TEMPERATURE CORRECTION METHOD BASED ON K-SPACE ENERGY SPECTRUM ANALYSIS AND SYSTEM
Disclosed are a magnetic resonance temperature correction method based on k-space energy spectrum analysis and a system. The method includes: filling a k-space data matrix of magnetic resonance with zeros row by row, and performing an inverse Fourier transform on the k-space data matrix after filling each row of zeros, to obtain a reconstructed image; drawing a pixel intensity variation curve according to a pixel intensity of each pixel in all reconstructed images and a number of rows filled with zeros, and obtaining echo error according to the pixel intensity variation curve, calculation an actual echo time, and calculating a corresponding temperature variation value based on the
MAGNETIC SENSOR AND CURRENT SENSOR
A magnetic sensor includes a magnetoresistive effect element having a sensitivity axis in a specific direction. The magnetoresistive effect element has on a substrate, a laminate structure in which a fixed magnetic layer and a free magnetic layer are laminated with a nonmagnetic material layer interposed therebetween and includes at a side of the free magnetic layer apart from the nonmagnetic material layer, a first antiferromagnetic layer which generates an exchange coupling bias with the free magnetic layer and aligns a magnetization direction thereof in a predetermined direction in a magnetization changeable state. The free magnetic layer includes a first ferromagnetic layer in contact with the first antiferromagnetic layer to be exchange-coupled therewith and a magnetic adjustment layer at a side of the first ferromagnetic layer apart from the first antiferromagnetic layer. The magnetic adjustment layer contains at least one iron group element and at least one platinum group element.
MAGNETIC FIELD CLOSED LOOP SENSORS WITH OFFSET REDUCTION
Magnetic field closed loop sensors including offset reduction circuitry to reduce undesired baseband components attributable to offset associated with magnetoresistance elements are described. A superimposed signal including a main signal portion indicative of a parameter of a target and an offset reduced signal portion is coupled to feedback circuitry. The feedback circuitry generates a feedback signal to drive a feedback coil. Main processing circuitry is operative to extract the main signal portion from the superimposed signal and produce a sensor output signal based on the main signal portion. Example offset reduction circuitry can take the form of AC coupling circuitry or a ripple reduction loop.
Magnetic sensor
A magnetic sensor includes first to fourth resistor sections and a plurality of MR elements. Each of the plurality of MR elements belongs to any of first to fourth groups. The first to fourth groups are defined based on the areas of top surfaces of the MR elements. The first resistor section, the second resistor section, the third resistor section, and the fourth resistor section are constituted of the first group, the second group, the third group, and the fourth group, respectively; the second group, the first group, the fourth group, and the third group, respectively; the first group, the fourth group, the third group, and the second group, respectively; or the third group, the second group, the first group, and the fourth group, respectively.
Frequency detection on sensor integrated circuits
According to an embodiment of the present disclosure, an integrated circuit includes: at least one sensing element configured to generate a sensed signal responsive to an electrical or magnetic phenomenon; an analog-to-digital converter configured to convert the sensed signal into a digital signal; and a digital processor configured to detect a target frequency of the electrical or magnetic phenomenon by iteratively applying a first real-valued coefficient to samples of the digital signal using real-valued arithmetic.
Stress and temperature compensated hall sensor, and method
An integrated semiconductor device for measuring a magnetic field, comprising: a Hall sensor, a first lateral isotropic sensor having a first stress sensitivity and a first temperature sensitivity, a second lateral isotropic sensor having a second stress sensitivity and a second temperature sensitivity, optional amplifying means, digitization means; and calculation means configured for calculating a stress and temperature compensated Hall value in the digital domain, based on a predefined formula which can be expressed as an n-th order polynomial in only two parameters. These parameters may be obtained directly from the sensor elements, or they may be calculated from a set of two simultaneous equations. A method of obtaining a Hall voltage signal, and compensating said signal for stress and temperature drift.
Z MAGNETIC FIELD SENSORS WITH PLANAR CALIBRATION COILS
The innovative concept described herein relates to a sensor chip having at least two magnetic field sensors that are arranged adjacently to one another on the sensor chip and measure perpendicularly to the chip plane, wherein at least one of the magnetic field sensors has a planar coil arranged on it that is configured to generate a magnetic field directed perpendicularly to the chip plane. A controller is able to operate the magnetic field sensors in a calibration mode, in which the planar coil generates the magnetic field. For the purpose of calibrating the magnetic field sensors, a differential measurement may be taken that involves the response signal from one magnetic field sensor being subtracted from the response signal from the other magnetic field sensor.
Dual magnetometer calibration
Examples of systems and methods for calibrating or operating a magnetic sensor for sensor temperature or operating conditions are provided. The magnetic sensor can comprise a dual magnetometer sensor that comprises a first, low-power-consumption magnetometer (e.g., a magneto-inductive magnetometer) and a second higher-power-consumption magnetometer (e.g., a magneto-resistive magnetometer). The second magnetometer can have a lower unit-to-unit variation in temperature calibration parameters and can be used to temperature-correct readings from the first magnetometer. The magnetic sensor can dynamically switch between usage of the first magnetometer and the second magnetometer in order to provide a dynamic sample rate that can depend on conditions within the sensor or external to the sensor.
Vector length variance check for functional safety of angle sensors
A magnetic angle sensor system includes a first magnetic sensor configured to generate a first sensor signal, a second magnetic sensor configured to generate a second sensor signal, and at least one signal processor configured to: generate an angle signal including an angular value corresponding to an orientation of a magnetic field based on the first sensor signal and the second sensor signal; generate a vector length signal comprising a plurality of vector lengths corresponding to the first sensor signal and the second sensor signal; and extract at least one spectral component of the vector length signal, the at least one spectral component being indicative of a vector length variance between at least two consecutively sampled vector lengths of the plurality of vector lengths.