What is claimed is:
1. An inductance integrated in a monolithic circuit, including a conductive spiral having an internal end connected to a connection track, the spiral and the connection track belonging to a same metallization level, wherein the connection between the internal end of the spiral and the connection track is formed by a connecting track belonging to a metallization level higher than the metallization level of the spiral, the monolithic circuit including at least three metallization levels, the spiral and the connecting track belonging to an intermediate metallization level between two metallization levels.
2. The inductance of claim 1, wherein the monolithic circuit includes a ground plane surrounding the spiral and the connection track and which is formed in the same metallization level.
3. The inductance of claim 1, wherein the connection track connects the spiral to a passive component integrated to the monolithic circuit.
4. The inductance of claim 1, wherein the connection track connects the spiral to a pad accessible from the outside of the monolithic circuit.
5. The inductance of claim 1, wherein the spiral and the connection track are covered with an insulating layer on which is formed the connecting track, the connecting track being connected to the spiral and to the connection track by two vias crossing the insulating layer.
6. The inductance of claim 1, wherein the spiral and the connection track are covered with an insulating layer on which is formed the connecting track, the insulating layer including two openings in which extend the two ends of the connecting track to respectively connect to the spiral and to the connection track.
7. The inductance of claim 1, wherein the substrate is glass.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An angle measurement system comprising:
a magnet coupled to a rotating member and adapted to provide a magnetic field which rotates with the rotating member about a rotational axis of the rotating member;
an integrated circuit angle sensor disposed within the magnetic field at a radially off-center position from the rotational axis and including:
first and second bridges of magneto resistive elements configured to respectively provide first and second signals representative of substantially orthogonal first and second directional components of the magnetic field and together representative of an angular position of the rotating member; and
a set of adjustment parameters for adjusting attributes of the first and second signals having values selected to minimize errors in the first and second signals.
2. The angle measurement system of claim 1, wherein the magnet comprises a ring magnet coupled about the rotating member at a position along shaft away from ends of the shaft.
3. The angle measurement system of claim 1, wherein the set of adjustment parameters have values selected to minimize errors in the first and second signals caused by non-uniformity of the magnetic field at the radially off-center position.
4. The angle measurement system of claim 1, wherein the set of adjustment parameters includes a first and a second amplitude parameter and a first and a second offset parameter for respectively adjusting an amplitude and an offset of the first and second signals.
5. The angle measurement system of claim 4, wherein the magnetoresistive elements comprise anisotropic magnetoresistive elements.
6. The angle measurement system of claim 4, wherein the set of adjustment parameters includes an offset parameter for one of the first and second signals to adjust a phase of the one of the first and second signals.
7. The angle measurement system of claim 6, wherein the magnetoresistive elements comprise giant magnetoresistive elements.
8. The angle measurement system of claim 1, wherein the first and second bridges are positioned adjacent to one another along a radius extending from the rotational axis and proximate to and in parallel with a surface of the magnet.
9. The angle measurement system of claim 1, wherein the integrated circuit is positioned at a radial distance from the axis of rotation which substantially minimizes variations in a magnitude of a position vector obtained from the first and second signals.
10. An integrated circuit for measuring an angular position of a rotating magnet field at a radially off-center position from an axis of rotation of the magnetic field, the integrated circuit comprising:
a first set of magnetoresistive elements and an associated first plurality of switches which can be operated to selectively interconnect different subsets of the first set of magnetoresistive elements to form a first sensing bridge at different positions within the integrated circuit, the first sensing bridge configured to provide a first signal representative of a first directional component of the magnetic field; and
a second set of magnetoresistive elements and an associated second plurality of switches which can be operated to selectively interconnect different subsets of the second set of magnetoresistive elements to form a second sensing bridge at different positions within the integrated circuit, the second sensing bridge configured to provide a second signal representative of a second directional component of the magnetic field;
wherein switches of the first and second pluralities of switches are operated such that the resulting first and second bridges are at positions within the integrated circuit that minimize errors in the first and second signals resulting from non-uniformity of the magnetic field at the radially off-center position.
11. The integrated circuit of claim 10, wherein the first and second bridges are at positions within the integrated circuit which substantially minimize magnitude variations of a vector based on the first and second signals.
12. The integrated circuit of claim 10, wherein the first and second bridges are adjacent to one another with the magnetic field along a radius extending from the rotational axis.
13. The integrated circuit of claim 10, wherein the first and second sets of magnetoresistive elements comprise giant magnetoresistive elements.
14. The integrated circuit of claim 10, wherein the first and second sets of magnetoresistive elements comprise anisotropic magnetoresistive elements.
15. A method for off-center measurement of an angular position of a rotating shaft, comprising:
providing a magnetic field which rotates with the shaft about an axis of rotation;
positioning an integrated circuit having first and second magnetoresistive sensing bridges within the magnetic field at a radially off-center position from the axis of rotation, the first and second magnetoresistive sensing bridges respectively providing first and second signals representative of first and second magnetic field directions, the integrated circuit having a set of adjustment parameters for modifying attributes of the first and second signals;
modifying values of the set of adjustment parameters until errors in the first and second signals are substantially minimized; and
determining an angular position of the shaft based on the first and second signals.
16. The method of claim 15, wherein the set of adjustment parameters includes a first and a second amplitude parameter and a first and a second offset parameter for respectively adjusting an amplitude and an offset of the first and second signals.
17. The method of claim 16, wherein the first and second magnetoresistive sensing bridges comprise anisotropic magnetoresistive elements.
18. The method of claim 16, wherein the set of adjustment parameters further includes an offset parameter to adjust a phase of one of the first and second signals, and wherein the first and second magnetoresistive sensing bridges comprise giant magnetoresistive elements.
19. The method of claim 15, including adjusting the radially off-center position until variations in a magnitude of a vector obtained from the first and second signals resulting from the non-uniformity of the magnetic field at the radially off-center position are substantially minimized.
20. The method of claim 15, wherein providing a magnetic field includes mounting a ring magnet about the rotating shaft away from ends of the shaft.
21. A method of calibrating an integrated circuit magnetoresistive angle sensor for measuring an angular position of a rotating shaft, the method comprising:
temporarily coupling a discrete angle sensor to the rotating shaft;
providing a test signal representative of the angular position of the rotating shaft via the discrete angle sensor;
positioning the integrated circuit in a magnetic field rotating with the rotating shaft at a radially off-center location from a rotational axis of the rotating shaft, the integrated circuit including a first and a second magnetoresistive sensing bridge respectively providing first and second signals representative of orthogonal first and second directional components of the magnetic field, and including a set of adjustment parameters for modifying attributes of the first and second signals;
determining a measured angular position of the rotating shaft from the first and second signals;
adjusting values of the set of parameters to modify attributes of the first and second signals until an error between the angular position provide by the test signal and the measured angular position from the integrated circuit is substantially minimized.
22. The method of claim 21, including adjusting values of the set of parameters to compensate for errors in the measured angular position resulting from non-uniformity of the magnetic field at the off-center position.
23. The method of claim 21, including:
determining a magnitude of a vector based on the first and second signals; and
adjusting the radial position of the integrated circuit until variations in the magnitude of the vector are substantially minimized.
24. The method of claim 23, wherein the integrated circuit includes a first set of magnetoresistive elements and an associated first plurality of switches which can be operated to selectively interconnect different subsets of the first set of magnetoresistive elements to form the first magnetoresistive sensing bridge at different positions within the integrated circuit, and a second set of magnetoresistive elements and an associated second plurality of switches which can be operated to selectively interconnect different subsets of the second set of magnetoresistive elements to form the second magnetoresistive sensing bridge at different positions within the integrated circuit, and wherein adjusting the radial position includes operating the first and second pluralities of switches such that the resulting first and second magnetoresistive sensing bridges are at positions within the integrated circuit that the variations in the magnitude of the vector are substantially minimized.
25. The method of claim 23, wherein the first and second magnetoresistive sensing bridges comprise giant magnetoresistive sensing elements.
26. The method of claim 23, wherein the first and second magnetoresistive sensing bridges comprise anisotropic magnetoresistive sensing elements.