Abstract: The invention relates to a vertical Hall sensor integrated in a semiconductor chip and a method for the production thereof. The vertical Hall sensor has an electrically conductive well of a first conductivity type, which is embedded in an electrically conductive region of a second conductivity type. The electrical contacts are arranged along a straight line on a planar surface of the electrically conductive well. The electrically conductive well is generated by means of high-energy ion implantation and subsequent heating, so that it has a doping profile which either has a maximum which is located at a depth T1 from the planar surface of the electrically conductive well, or is essentially constant up to a depth T2.

Abstract: A stress sensor (1) for detecting mechanical stress in a semiconductor chip (2) has a Wheatstone bridge formed by four integrated resistors R1 to R4, the resistors R1 and R4 being p-type resistors and the resistors R2 and R3 being n-type resistors.

Abstract: A vertical Hall sensor which is integrated in a semiconductor chip has at least 6 electric contacts which are arranged along a straight line on the surface of the semiconductor chip. The electric contacts are wired according to a predetermined rule, namely such that when the contacts are numbered through continuously and repeatedly with the numerals 1, 2, 3 and 4 starting from one of the two outermost contacts, the contacts to which the same numeral is assigned are electrically connected with each other.

Abstract: A magnetic angle sensor 100 comprises a bulk substrate; a circular well 101 provided upon the bulk substrate; an even numbered plurality of electrodes 102a-102x spaced at regular intervals in a ring formation over the circular well; and a pair of biasing electrodes for selectively applying a progressive succession of differently directed bias currents 104 to and/or using the said ring of electrodes 102 to provide a succession of Hall potentials indicative of the relative magnitude of successive differently oriented magnetic field components B in the plane of the magnetic angle sensor 100. The sensor 100 operates cyclically and the full progressive succession cycle involves applying and/or using each electrode 102 in the ring at least once for applying a bias current and/or sensing a Hall potential. In such a manner, the full cycle comprises the progressive succession of the axis of measurement of the sensor 100 through a complete rotation within the plane of the sensor.

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.

Abstract: A vertical Hall sensor which is integrated in a semiconductor chip has at least 6 electric contacts which are arranged along a straight line on the surface of the semiconductor chip. The electric contacts are wired according to a predetermined rule, namely such that when the contacts are numbered through continuously and repeatedly with the numerals 1, 2, 3 and 4 starting from one of the two outermost contacts, the contacts to which the same numeral is assigned are electrically connected with each other.

Abstract: A Hall sensor comprises two separate wells and each having respective contacts provided thereover. An oppositely directed bias current is supplied via contacts. Accordingly, a differential signal can be obtained from the two output contacts. As in each well the middle contact can be precisely centred between the two outer contacts, the intrinsic offset is small. The sensor 300 can be subjected to reversed operation by reversing the bias current direction. This provides a sensor with a low and temperature-stable offset.

Abstract: A magnetic angle sensor 100 comprises a bulk substrate; a circular well 101 provided upon the bulk substrate; an even numbered plurality of electrodes 102a-102x spaced at regular intervals in a ring formation over the circular well; and means for selectively applying a progressive succession of differently directed bias currents 104 to and/or using the said ring of electrodes 102 to provide a succession of Hall potentials indicative of the relative magnitude of successive differently oriented magnetic field components B in the plane of the magnetic angle sensor 100. The sensor 100 operates cyclically and the full progressive succession cycle involves applying and/or using each electrode 102 in the ring at least once for applying a bias current and/or sensing a Hall potential. In such a manner, the full cycle comprises the progressive succession of the axis of measurement of the sensor 100 through a complete rotation within the plane of the sensor.

Abstract: A method of determining the position of a probe relative to a scale wherein the probe contains a sensor of the type comprising one or more pairs of orthogonal sensing elements X, Y operable to measure properties varying locally with the position of the probe relative to the scale. In use, a sinusoidally varying bias Ix, Iy is applied to each of the elements X, Y. The resultant outputs of elements X and Y are fed to summing means 101 and difference means 102. The summing means 101 is operable to output a summed signal Vsum equal to the instantaneous sum of Vx and Vy. The difference means 102 is operable to output a difference signal Vdiff equal to the instantaneous difference between Vx and Vy. The outputs Vsum and Vdiff are fed into a phase comparator 103, which is operable to determine the phase difference between them. The phase angle between Vsum and Vdiff provides an indication of the position of the probe relative to the scale.

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.

Abstract: The invention relates to a sensor for detecting the direction of a magnetic field in a plane whose direction can be defined by the indication of a polar angle ?. Said sensor comprises a number of n magnetic field sensors (3.0 to 3.7). A measurement axis (8.1 to 8.4) is assigned to each magnetic field sensor in such a manner that the absolute value of the output signal of the magnetic field sensor is largest when the magnetic field runs parallel to the measuring axis. All measuring axes intersect at a common point (5). The number k of measuring axes is equal to at least three. An operating mode is provided during which two magnetic field sensors are selected for calculating the angle ?. These two magnetic field sensors belong to different measuring axes, and the values of the output signals thereof are less than those of the output signals of the magnetic field sensors belonging to the other measuring axes.

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.

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.

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.

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.

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.

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.

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.

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.

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.