Patents Assigned to Sentron AG
  • Publication number: 20070164727
    Abstract: A device for measuring current comprises a magnetic field sensor (2) for measuring the magnetic field produced by a current I flowing through a current conductor (1) and a yoke (3) of a magnetic material with a relative permeability of at least 100. The magnetic field sensor (2) preferably comprises a semiconductor chip with at least one Hall element and an electronic circuit for the operation of the Hall element. Two magnetic field concentrators (7, 8) separated by an air gap (6) are arranged on a surface of the semiconductor chip such that field lines (9) of the magnetic field (see FIG. 3) that issue from the first magnetic field concentrator (7) in the vicinity of the air gap (6) and impinge on the second magnetic field concentrator (8) in the vicinity of the air gap (6) pass through the at least one Hall element.
    Type: Application
    Filed: January 16, 2007
    Publication date: July 19, 2007
    Applicant: Sentron AG
    Inventors: Robert Racz, Samuel Huber, Markus Gloor
  • Publication number: 20070080676
    Abstract: An assembly group for current measurement comprises a conductor plate with three cuts and a measuring element placed on the conductor plate that has a difference sensor formed from two magnetic field sensors. By means of the three cuts a first and a second conductor section are formed in the conductor plate, wherein the current direction in the second conductor section runs opposite to the current direction in the first conductor section. The first magnetic field sensor is located above the first conductor section and the second magnetic field sensor is located above the second conductor section. The magnetic field sensors are sensitive to a magnetic field that runs parallel to the surface of the conductor plate and orthogonal to the current direction in the two conductor sections.
    Type: Application
    Filed: October 3, 2006
    Publication date: April 12, 2007
    Applicant: Sentron AG
    Inventors: Robert Racz, Samuel Huber
  • Publication number: 20070029998
    Abstract: A sensor for detecting the direction of a magnetic field in a plane, the direction of which is defined by a polar angle ?, has a number n of magnetic field sensors. A measuring axis is assigned to each magnetic field sensor in such a way that the absolute value of the output signal of the magnetic field sensor is at its greatest when the magnetic field runs parallel to the measuring axis. All measuring axes intersect at a common point. The number k of measuring axes amounts to at least three and an operating mode is foreseen with which for calculation of the angle ? two magnetic field sensors are selected that belong to different measuring axes and the output signals of which in terms of value are less than the output signals of the magnetic field sensors that belong to other measuring axes.
    Type: Application
    Filed: August 22, 2003
    Publication date: February 8, 2007
    Applicant: Sentron AG
    Inventors: Radivoje Popovic, Christian Schott
  • Patent number: 7129691
    Abstract: A low-cost, current sensor suitable for mass production and a manufacturing method thereof are provided. The current sensor is small with high sensitivity and can be packaged in a standard assembly line which is normally used when an integrated circuit is manufactured. Further, it is possible to obtain a sufficient shielding effect against a disturbance flux without degrading the detecting sensitivity of a flux. A first magnetic material 50 is bonded to the lower part of a current conductor 22C. The first magnetic material 50 has the function of converging and amplifying a flux 3 generated by the current to be measured. A second magnetic material 51 is bonded above a magnetic sensor chip 20. The second magnetic material 51 has a shielding function against a disturbance flux entering from the outside.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: October 31, 2006
    Assignees: Sentron AG, Asahi Kasei EMD Corporation
    Inventors: Koji Shibahara, Radivoje Popovic, Yo Yamagata, Robert Racz
  • Publication number: 20060164080
    Abstract: A magnetic field sensor for the measurement of at least one component of a magnetic field comprises a ferromagnetic core that serves as a magnetic field concentrator, an excitation coil and a read-out sensor. The read-out sensor preferably comprises two sensors arranged in the vicinity of the outer edge of the ferromagnetic core and measures the at least one component of the magnetic field. The ferromagnetic core is ring-shaped or disc-shaped. On operation of the magnetic field sensor, a current is temporarily applied to the excitation coil in order to bring the ferromagnetic core into a state of predetermined magnetization in which the magnetization of the ferromagnetic core produces no signal in the read-out sensor.
    Type: Application
    Filed: July 29, 2003
    Publication date: July 27, 2006
    Applicant: SENTRON AG
    Inventors: Radivoje Popovic, Christian Schott
  • Patent number: 7038448
    Abstract: A magnetic field sensor for measuring at least two components of a magnetic field comprises a ferromagnetic core mounted on a semiconductor chip, an exciter coil to which a current can be applied and two read-out sensors. The ferromagnetic core is ring-shaped. The exciter coil is preferably formed from conductor tracks of the semiconductor chip and from bonding wires.
    Type: Grant
    Filed: May 21, 2002
    Date of Patent: May 2, 2006
    Assignee: Sentron AG
    Inventors: Christian Schott, Radivoje Popovic, Robert Racz
  • Publication number: 20060011999
    Abstract: A symmetrical vertical Hall element comprises a well of a first conductivity type that is embedded in a substrate of a second conductivity type and which is contacted by four contacts serving as current and voltage contacts. From the electrical point of view, such a Hall element with four contacts can be regarded as a resistance bridge formed by four resistors R1 to R4 of the Hall element. From the electrical point of view, the Hall element is then regarded as ideal when the four resistors R1 to R4 have the same value. The invention suggests a series of measures in order to electrically balance the resistance bridge. A first measure exists in providing at least one additional resistor. A second measure exists in locally increasing or reducing the electrical conductivity of the well. A third measure exists in providing two Hall elements that are electrically connected in parallel in such a way that their Hall voltages are equidirectional and their offset voltages are largely compensated.
    Type: Application
    Filed: September 10, 2002
    Publication date: January 19, 2006
    Applicant: Sentron AG
    Inventors: Christian Schott, Radivoje Popovic, Pierre-Andre Besse, Enrico Schurig
  • Patent number: 6969988
    Abstract: An angle detection apparatus for detecting an angle of a rotatable magnetic field source comprises first and second magnetic sensor units for detecting first and second magnetic components of the magnetic field of the magnetic field source, driving means for driving the first and second magnetic sensor unit and control means. The control means control an output signal of the first magnetic sensor unit so as to have a fixed value and the driving means drive the second magnetic sensor unit according to the same drive conditions as those applied to the first magnetic sensor unit at the time when the first magnetic sensor unit is controlled by said control means so that an output signal of the second magnetic sensor unit is proportional to the tangent of said angle.
    Type: Grant
    Filed: March 20, 2003
    Date of Patent: November 29, 2005
    Assignees: Asahi Kasei EMD Corporation, Sentron AG
    Inventors: Katsumi Kakuta, Christian Schott
  • Patent number: 6731108
    Abstract: A magnetic position encoder comprises a magnetic field source and a magnetic field sensor which are movable relative to each other along a given path. The magnetic field sensor measures two components of the magnetic field produced by the magnetic field source. From the measured components a position signal is then derived which represents the relative position of the magnetic field sensor and magnetic field source. Embodiments of the position encoder in accordance with the invention are characterised in that the determination of the position signal includes a division of the two measured components of the magnetic field. These embodiments in accordance with the invention have the advantage that the position signal is a linear function of the position.
    Type: Grant
    Filed: March 20, 2002
    Date of Patent: May 4, 2004
    Assignee: Sentron AG
    Inventors: Ivano Zalunardo, Christian Schott, Radivoje Popovic
  • Patent number: 6545462
    Abstract: A sensor for the detection of the direction of a magnetic field comprises one single magnetic field concentrator with a flat shape and at least a first horizontal Hall-effect element and a second horizontal Hall-effect element, whereby the Hall-effect elements are arranged in the area of the edge of the magnetic field concentrator. Within its environment, the magnetic field concentrator alters the course of the field lines of the magnetic field and, in particular, has the effect that the field lines which, in the absence of the magnetic field concentrator would run parallel to the surface of the Hall-effect elements penetrate the Hall-effect elements almost vertically to their surface. Instead of horizontal Hall-effect elements, vertical Hall-effect elements can also be used when they are arranged beside the magnetic field concentrator. The sensor is particularly suitable as an angle sensor.
    Type: Grant
    Filed: August 8, 2001
    Date of Patent: April 8, 2003
    Assignee: Sentron AG
    Inventors: Christian Schott, Robert Racz, Radivoje Popovic
  • Patent number: 6376321
    Abstract: A pn-junction in a semiconductor element is made in that, within a zone of a first conductivity type, by means of implantation, a first and second zone of a second conductivity type are formed which are initially separated from each other, with subsequent diffusion processes, as a result of lateral diffusion, the first and second zones combine into a connected well, by means of implantation, a further zone of the first conductivity type is formed which completely overlaps the first zone of the second conductivity type and which is larger than the first zone, and which does not touch the second zone of the second conductivity type.
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: April 23, 2002
    Assignee: Sentron AG
    Inventors: Radivoje Popovic, Alexandre Pauchard, Alexis Rochas
  • Patent number: 6278271
    Abstract: A magnetic field sensor for measurement of the three components (Bx, By, Bz) of a magnetic field comprises a Hall-effect element (1) and an electronic circuit (22). The Hall-effect element (1) comprises an active area (18) of a first conductivity type which is contacted with voltage and current contacts (2-5 or 6-9). Four voltage contacts (2-5) are present which are connected to inputs of the electronic circuit (22). By means of summation or differential formation of the electrical potentials (V2, V3, V4, V5) present at the voltage contacts (2-5), the electronic circuit (22) derives three signals (Vx, Vy, Vz) which are proportional to the three components (Bx, By, Bz) of the magnetic field.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: August 21, 2001
    Assignee: Sentron AG
    Inventor: Christian Schott
  • Patent number: 6184679
    Abstract: A magnetic field sensor has two flux concentrators which serve to strengthen a magnetic field to be measured and which are separated by an air gap. Two Hall elements are arranged outside the air gap in such a way that at least a part of the field lines which lead from the first to the second flux concentrator pass through the two Hall elements in approximately opposite directions. Such a magnetic field sensor is less sensitive to external interference fields. It is suitable for the measurement of very weak magnetic fields and also for use as a current and/or energy sensor.
    Type: Grant
    Filed: May 10, 1999
    Date of Patent: February 6, 2001
    Assignee: Sentron AG
    Inventors: Radivoje Popovic, Robert Racz, Jan Hrejsa, Hubert Blanchard
  • Patent number: 5942895
    Abstract: A magnetic field sensor has two flux concentrators which serve to strengthen a magnetic field to be measured and which are separated by an air gap. Two Hall elements are arranged outside the air gap in such a way that at least a part of the field lines which lead from the first to the second flux concentrator pass through the two Hall elements in approximately opposite directions. Such a magnetic field sensor is less sensitive to external interference fields. It is suitable for the measurement of very weak magnetic fields and also for use as a current and/or energy sensor.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: August 24, 1999
    Assignee: Sentron AG
    Inventors: Radivoje Popovic, Robert Racz, Jan Hrejsa, Hubert Blanchard