Integrated sensor

• US 7,259,545 B2
• Filed: 02/11/2003
• Issued: 08/21/2007
• Est. Priority Date: 02/11/2003
• Status: Active Grant

• Current Assignee: Allegro Microsystems Incorporated (Sanken Electric Company Limited)
• Original Assignee: Allegro Microsystems Incorporated (Sanken Electric Company Limited)
• Inventors: Dickinson, Richard, Vig, Ravi, Forrest, Glenn, Stauth, Jason
• Primary Examiner(s): Nguyen; Vinh P.
• Application Number:
  US10/364,442
• Publication Number:
  US 20040155644A1
• Time in Patent Office: 1,652 Days
• Field of Search: 324117 R-117 H, 324126-127, 324251-252, 338/32.R, 338/32.H
• US Class Current: 324/117.00R
• CPC Class Codes: G01R 15/205 using magneto-resistance devices, e.g. field plates
• CPC Class Codes: G01R 15/207 Constructional details independent of the type of device used
• CPC Class Codes: G01R 33/09 Magnetoresistive devices
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/4903 Connectors having different sizes, e.g. different diameters
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

Abstract

An integrated sensor includes a magnetoresistance element electrically coupled to a device disposed on or integrated in a silicon substrate. A conductor is provided proximate to the magnetoresistance element. The integrated sensor can be used to provide various devices, such as a current sensor, a magnetic field sensor, or an isolator. Further, the integrated sensor can be used in an open loop configuration or in a closed loop configuration in which an additional conductor is provided. The magntoresistance element may be formed over the silicon substrate or on a separate, non-silicon substrate. Also described is an integrated sensor comprising a substrate, a magnetic field transducer disposed over a surface of the substrate, and a conductor disposed over the surface of the substrate proximate to the magnetic field transducer. The magnetic field transducer can be a Hall effect transducer or a magnetoresistance element.

Claims

1. An electronic circuit, comprising:

a silicon substrate;

a device supported by the silicon substrate selected from among a passive electronic component and an active electronic component;

a conductor disposed over said silicon substrate;

an insulating layer disposed between said silicon substrate and said conductor; and

a magnetoresistance element disposed over said conductor and electrically coupled to said device, wherein said magnetoresistance element is responsive to a magnetic field generated by a current through said conductor.

2. The electronic circuit of claim 1, wherein said conductor is a secondary conductor and said circuit further comprises a primary conductor having at least a portion disposed proximate said magnetoresistance element, wherein said magnetoresistance element is also responsive to a magnetic field generated by a current through said primary conductor.

3. The electronic circuit of claim 2, wherein said device comprises an amplifier having an input terminal coupled to said magnetoresistance element and an output terminal coupled to said secondary conductor and at which an output signal is provided, wherein said output signal is indicative of a current through said primary conductor.

4. The electronic circuit of claim 1, wherein said device comprises an amplifier coupled to the magnetoresistance element for providing an output signal, wherein said output signal is indicative of a current through said conductor.

5. The electronic circuit of claim 1, wherein said device comprises an amplifier having an input terminal coupled to said magnetoresistance element and an output terminal at which an output signal is provided, said output signal being indicative of an external magnetic field.

6. The electronic circuit of claim 1, wherein said magnetoresistance element is a selected one of an anisotropic magnetoresistance element or a giant magnetoresistance element.

7. The electronic circuit of claim 1, wherein said conductor comprises more than one loop.

8. The electronic circuit of claim 1, further including a magnetic flux concentrator disposed proximate said conductor.

9. The electronic circuit of claim 1, wherein said magnetic field transducer comprises two magnetoresistance elements coupled in series.

10. A current sensor, comprising:

a silicon substrate having a surface;

a magnetic field transducer disposed over said surface of said silicon substrate;

a secondary conductor disposed over said surface of said silicon substrate proximate said magnetic field transducer;

a primary conductor disposed proximate said magnetic field transducer; and

a dielectric layer disposed between said primary conductor and said silicon substrate, wherein said magnetic field transducer is responsive to a primary magnetic field generated by a primary current through said primary conductor and to a secondary magnetic field generated by a secondary current through said secondary conductor.

11. The current sensor of claim 10, further comprising an amplifier having an input terminal coupled to said magnetic field transducer and an output terminal coupled to said secondary conductor and at which an output signal is provided, said output signal being indicative of said primary magnetic field.

12. The current sensor of claim 10, wherein the magnetic field transducer includes one or more magnetoresistance elements.

13. The current sensor of claim 10, wherein said magnetic field transducer comprises two magnetoresistance elements coupled in series.

14. An electronic circuit, comprising:

a substrate having a surface;

a device supported by said surface of said substrate;

a conductor disposed over said surface of said substrate;

an insulating layer disposed between said substrate and said conductor; and

a magnetic field transducer disposed over said conductor, wherein said conductor is adapted to carry an electrical current to generate a first magnetic field, and wherein said electronic circuit is responsive to the first magnetic field.

15. The electronic circuit of claim 14 wherein said conductor is a secondary conductor and said circuit further comprises:

a primary conductor disposed proximate said magnetic field transducer, wherein said primary conductor is adapted to carry an electrical current to generate a second magnetic field, and wherein said electronic circuit is further responsive to the second magnetic field; and

a dielectric layer disposed between said primary conductor and said substrate.

16. The electronic circuit of claim 15, wherein said device comprises an amplifier having an input terminal coupled to said magnetic field transducer and an output terminal coupled to said secondary conductor and at which an output signal is provided, wherein said output signal is indicative of a current through said primary conductor.

17. The electronic circuit of claim 15, wherein said primary conductor is U-shaped.

18. The electronic circuit of claim 14, wherein said device comprises an amplifier coupled to said magnetic field transducer for providing an output signal, wherein said output signal is indicative of a current through said conductor.

19. The electronic circuit of claim 14, wherein said device comprises an amplifier having an input terminal coupled to said magnetic field transducer and an output terminal at which an output signal is provided, said output signal being indicative of an external magnetic field.

20. The electronic circuit of claim 14, wherein said magnetic field transducer comprises two magnetoresistance elements coupled in series.

21. The electronic circuit of claim 20, wherein each of said magnetoresistance elements has an opposite polarization with respect to the other of said magnetoresistance elements.

22. The electronic circuit of claim 20, wherein each of said magnetoresistance elements have the same polarization.

23. The electronic circuit of claim 22, wherein said conductor is U-shaped.

24. The electronic circuit of claim 14, wherein said magnetic field transducer comprises two pairs of magnetoresistance elements, wherein each pair comprises two magnetoresistance elements coupled in series, and said two pairs are coupled together to form a Wheatstone bridge.

25. The electronic circuit of claim 24, wherein the two magnetoresistance elements of each pair are oppositely polarized.

26. The electronic circuit of claim 24, wherein one of the two magnetoresistance elements of each pair is magnetically unresponsive.

27. The electronic circuit of claim 24, wherein each of the two magnetoresistance elements of both pairs has the same polarization.

28. The electronic circuit of claim 14, wherein said conductor is U-shaped.

29. The electronic circuit of claim 14, wherein said conductor comprises more than one loop.

30. The electronic circuit of claim 14, further including a magnetic flux concentrator disposed proximate said conductor.

31. The electronic circuit of claim 14, wherein said magnetic field transducer comprises a magnetoresistance element.