Sensor device

Patent metadata

Field	Value
Publication number	US-9933495-B2
Application number	US-201514674249-A
Country	US
Kind code	B2
Filing date	Mar 31, 2015
Priority date	Mar 31, 2014
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

A sensor device for suppressing a magnetic stray field, having a semiconductor body, a first pixel cell and a second pixel cell integrated into a surface of the semiconductor body together with a circuit arrangement. Each pixel cell has a first magnetic field sensor and a second magnetic field sensor to detect a magnetic field in the x-direction and a magnetic field in the y-direction. The first pixel cell is spaced apart from the second pixel cell along a connecting line, and the substrate and the semiconductor body are disposed in the same IC package. A magnet is provided that has a planar main extension surface in the direction of an x-y plane and has a magnetization with four magnetic poles in the direction of the x-y plane. The IC package is spaced apart from the main extension surface of the magnet in the z-direction and at least partially within a ring magnet.

First claim

What is claimed is:

1. A sensor device for suppressing a magnetic stray field, the sensor device comprising:
a semiconductor body with a surface formed in an x-y plane and a back surface, an x-direction and a y-direction being formed orthogonal to one another, the semiconductor body being arranged on a substrate, the substrate and the semiconductor body being disposed in an IC package;
a first pixel cell and a second pixel cell, the first and second pixel cells being formed in the surface of the semiconductor body together with a circuit arrangement, each of the first and second pixel cells having a first magnetic field sensor and a second magnetic field sensor, the first magnetic field sensor detecting a magnetic field in the x-direction and the second magnetic field sensor detecting a magnetic field in the y-direction, the first pixel cell being spaced apart from the second pixel cell along a connecting line;
an axis formed in a z-direction, the z-direction being configured orthogonal to the x-y plane; and
a magnet having a planar main extension surface in the direction of the x-y plane and having a magnetization with four magnetic poles in the direction of the x-y plane, the surface of the semiconductor body being oriented parallel to the main extension surface of the magnet;
wherein the magnet is mounted rotatable around the z-direction relative to an IC housing of the IC package, and an imagined lengthening of the axis penetrates the connecting line in the middle and penetrates the magnet in a center of gravity of a main extension surface of the magnet; and
wherein the IC package is spaced apart from the main extension surface of the magnet in a z-direction, or
wherein the magnet is configured as a ring magnet formed in the x-y plane and the IC package is arranged at least partially within the ring magnet, wherein the four magnetic poles are arranged as segments, and wherein the axis runs through a middle of a ring of the ring magnet.

2. The sensor device according to claim 1 , wherein each pixel cell comprises a third magnetic field sensor, wherein the third magnetic field sensor detects a magnetic field in the z-direction, and wherein the z-direction is configured orthogonal to the x-direction and orthogonal to the y-direction so that each pixel cell is formed as a 3-dimensional magnetic field sensor.

3. The sensor device according to claim 1 , wherein the first and second pixel cells are each formed near an outer edge of the semiconductor body to form a large distance to one another.

4. The sensor device according to claim 1 , wherein an integrated circuit is formed on the semiconductor body between and/or next to the first and second pixel cells, and wherein the integrated circuit has an electrical functional connection to the first and second pixel cells.

5. The sensor device according to claim 1 , wherein the first and second magnetic field sensors in the first pixel cell and the magnetic field sensors in the second pixel cell have a common center of gravity in order to determine a magnetic flux at a same point of each pixel cell.

6. The sensor device according to claim 1 , wherein the first and second magnetic field sensors each have a main extension surface, and wherein the main extension surfaces of the magnetic field sensors are formed in pairs at right angles to one another.

7. The sensor device according to claim 6 , wherein the first and second magnetic field sensors are formed as Hall sensors, wherein two of the Hall sensors are formed as vertical Hall sensors, and wherein the main extension surface of each of the two vertical Hall sensors is formed substantially perpendicular to the surface of the semiconductor body.

8. The sensor device according to claim 2 , wherein the third magnetic field sensor of each of the first or second pixel cell is configured as a Hall plate.

9. The sensor device according to claim 1 , wherein the magnet is configured as a circle in the x-y plane, wherein a radius of the circle is greater than half the length of the connecting line or, wherein, provided the magnet is not configured as a ring magnet, the magnet is formed as a square and half of the diagonal of the square is greater than half the length of the connecting line.

10. The sensor device according to claim 1 , wherein the magnetic poles are formed as four equally large segments of a circle.

11. The sensor device according to claim 1 , wherein the sensor device detects a rotation angle of a magnet connected to the axis or to a shaft.

12. The sensor device according to claim 1 , wherein the sensor device determines a rotation angle in a case of the rotation angle of the magnet connected to a stationary axis or to a shaft.

13. The sensor device according claim 1 , wherein the sensor device is configured for a differential operation for detecting the rotation angle of an axis and a shaft.

Assignees

• Micronas Gmbh
• Tdk Micronas Gmbh

Inventors

• Kaufmann Timo
• Franke Joerg
• Ring Andreas

Classifications

• G01R33/025 Primary

  Compensating stray fields {(G01R33/0017 takes precedence)} · CPC title

• G01R33/0094

  Sensor arrays · CPC title

• G01R33/07

  Hall effect devices · CPC title