Three dimensional magnetic field sensor

• US 6,278,271 B1
• Filed: 03/29/1999
• Issued: 08/21/2001
• Est. Priority Date: 03/30/1998
• Status: Expired due to Term

• Current Assignee: Melexis Tessenderlo NV
• Original Assignee: Sentron AG (Sensinnovat BVBA)
• Inventors: Schott, Christian
• Primary Examiner(s): Strecker, Gerard R.
• Application Number:
  US09/280,200
• Time in Patent Office: 876 Days
• Field of Search: 324/207.2, 324/235, 324/247, 324/251, 324/117.H, 327/511, 257/421, 257/422, 257/426, 257/427, 338/32.H
• US Class Current: 324/251
• CPC Class Codes: G01R 33/0206 Three-component magnetometers
• CPC Class Codes: G01R 33/07 Hall effect devices

Abstract

A magnetic field sensor for measurement of the three components (B_x, B_y, B_z) 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 (V_x, V_y, V_z) which are proportional to the three components (B_x, B_y, B_z) of the magnetic field.

Claims

1. Magnetic field sensor for measurement of the three components of a magnetic field comprising a Hall-effect element and an electronic circuit, whereby the Hall-effect element has an active area of a first conductivity type which is contacted with voltage and current contacts whereby at least four current contacts for current feed and four voltage contacts are present, whereby the voltage contacts are connected to the electronic circuit which derives three signals, each by means of one of:

summation, differential, and both summation and differential formation of the electrical potentials present at the voltage contacts which are proportional to the three components of the magnetic field.

2. Magnetic field sensor according to claim 1 whereby the active area is neither laterally limited by an area of a second conductivity type nor itself laterally limits an area of a second conductivity type.

3. Magnetic field sensor according to claim 1 whereby the active area is laterally limited by an area of a second conductivity type and/or laterally limits an area of a second conductivity type.

4. Magnetic field sensor according to claim 1, whereby magnetic field concentrators are present which amplify the two components of the magnetic field directed parallel to the surface of the Hall-effect element in the area of the corresponding voltage contacts.

5. Magnetic field sensor according to claim 1, whereby the electronic circuit forms at least one signal by means of instrumentation amplifiers.

6. Magnetic field sensor according to claim 1, whereby a maximum of three current and/or voltage contacts are arranged along any direction.