Electrical current detector having a U-shaped current path and hall-effect device

• US 20040080307A1
• Filed: 10/20/2003
• Published: 04/29/2004
• Est. Priority Date: 12/20/1999
• Status: Active Grant

• Current Assignee: Sanken Electric Company Limited
• Original Assignee: Sanken Electric Company Limited
• Inventors: Ohtsuka, Koji
• Granted Patent: US 6,791,313 B2
• Time in Patent Office: Days
• US Class Current: 324/117H
• CPC Class Codes: H01L 2224/05569 the external layer being disposed on a redistribution layer on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48091 Arched
• 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 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H10N 52/101 Semiconductor Hall-effect devices

Abstract

A current detector having a Hall-effect device formed in a semiconductor substrate for giving an output voltage proportional to the magnitude of an electric current. Also included is a sheet-metal baseplate mechanically supporting the Hall-effect device. For handling a current of greater magnitude than heretofore, a U-shaped current path is defined in the baseplate as by cutting therein a J-shaped slit and a set of straight slits for bounding the opposite side edges of the path. The baseplate lies in sufficient proximity to the Hall-effect device to cause the same to develop a voltage indicative of the current magnitude on the current path.

Claims

1. A current detector for detecting or measuring an electric current, comprising:

(a) a Hall-effect device for generating a voltage proportional to magnetic field strength;

(b) two current path terminals for the inflow and outflow, respectively, of a current to be detected or measured; and

(c) a metal-made baseplate mechanically supporting the Hall-effect device, the baseplate being slitted to define a current path having a pair of opposite extremities connected respectively to the current path terminals, the current path being contiguous to the Hall-effect device for causing the same to generate a voltage proportional to the magnitude of a current flowing through the current path.

2. The current detector of claim 1 wherein the current path in the baseplate is in the shape of a U.

3. The current detector of claim 2, wherein the Hall-effect device has a primary working part for the development of the voltage proportional to the magnitude of the current flowing through the current path in the baseplate, the primary working part being substantially thoroughly contained within the U-shaped current path as seen in a direction normal to the baseplate.

4. The current detector of claim 2 wherein the baseplate has formed therein at least one slit bounding one side edge of the U-shaped current path, and at least one other slit bounding another side edge of the current path.

5. The current detector of claim 4 wherein said other edge of the current path is bounded by a plurality of straight slits cut into the baseplate.

6. Th current detector of claim 2 wherein the U-shaped current path is defined at least in part by a J-shaped slit cut into the baseplate.

7. The current detector of claim 2 wherein the U-shaped current path is defined at least in part by a pair of straight slits cut into the baseplate and extending in parallel spaced relationship to each other.

8. The current detector of claim 2 wherein the U-shaped current path is defined at least in part by a single straight slit cut into the baseplate.

9. The current detector of claim 2 wherein the baseplate is a generally rectangular piece of sheet metal, and wherein the current path terminals are integrally joined to one edge of the baseplate.

10. The current detector of claim 2 wherein the baseplate is a generally rectangular piece of sheet metal, wherein one current path terminal is integrally joined to a first edge of the baseplate and directly connected to one end of the U-shaped current path, and wherein the other current path terminal is integrally joined to a second edge, opposite to the first edge, of the baseplate and connected to the other end of the current path via an extension thereof.

11. The current detector of claim 10 wherein the baseplate has at least one slit cut therein from the first edge thereof to bound one side edge of the U-shaped current path, and another slit cut therein from the second edge thereof to form the extension of the current path.

12. The current detector of claim 11 wherein said one edge of the U-shaped current path is bounded by a J-shaped slit.

13. The current detector of claim 11 wherein said one edge of the U-shaped current path is bounded by a pair of straight slits cut into the baseplate so as to extend in parallel spaced relationship to each other.

14. The current detector of claim 1 further comprising an insulating layer interposed between the baseplate and the Hall-effect device.

15. The current detector of claim 14 further comprising a shielding plate interposed between the Hall-effect device and the insulating plate.

16. The current detector of claim 1 further comprising a plurality of lead terminals for connecting the Hall-effect device to external circuits, the lead terminals being made from the same sheet metal as is the baseplate.

17. The current detector of claim 16 further comprising an enclosure of electrically insulating material enveloping all the listed components of the current detector but parts of the current path terminals and the lead terminals.

18. The current detector of claim 1 wherein the Hall-effect device is formed in a semiconductor substrate in which there is also formed an amplifier for amplifying the output voltage of the Hall-effect device.

19. A current detector for detecting or measuring an electric current, comprising:

(a) two Hall-effect devices each for generating a voltage proportional to magnetic field strength;

(b) two current path terminals for the inflow and outflow, respectively, of a current to be detected or measured; and

(c) a metal-made baseplate mechanically supporting the Hall-effect devices, the baseplate being slitted to define a current path having a pair of opposite extremities connected respectively to the current path terminals, the current path being contigous to the Hall-effect devices for causing the same to generate voltages proportional to the magnitude of a current flowing through the current path;

(d) whereby the magnitude of the current flowing through the current path is detectable in terms of the sum of the absolute values of the output voltages of the Hall-effect devices.

20. The current detector of claim 19 wherein the current path in the baseplate is in the shape of an S.

21. The current detector of claim 20 wherein the baseplate is a generally rectangular piece of sheet metal having a first edge, a second edge opposite to the first edge, a third edge at right angles with the first and the second edge, and a fourth edge opposite to the third edge, wherein the baseplate has a first slit cut into the baseplate from the first edge thereof to bound part of one side edge of the S-shaped current path, and a second slit cut into the baseplate from the second edge thereof to bound part of another side edge of the current path, wherein the current path comprises a first part between the third baseplate edge and the second slit, a second part between the first baseplate edge and the second slit, a third part between the first and the second slit, a fourth part between the second baseplate edge and the first slit, and a fifth part between the fourth baseplate edge and the first slit, and wherein the two current path terminals are joined respectively to the first and the second edge of the baseplate in positions contiguous to the first and the fifth part of the current path.

22. The current detector of claim 21 wherein each Hall-effect device has a primary working part for the development of the voltage proportional to the magnitude of the current flowing through the current path in the baseplate, the primary working parts of the two Hall-effect devices being substantially thoroughly contained respectively between the first and the third part, and between the third and the fifth part, of the current path, both as seen in a direction normal to the baseplate.

23. The current detector of claim 19 further comprising an output circuit for combining the absolute values of the output voltages of the Hall-effect devices.

24. The current detector of claim 23 wherein the output circuit comprises:

(a) two amplifiers connected respectively to the Hall-effect devices; and

(b) arithmetic means connected to the amplifiers for providing an output representative of the sum of the absolute values of outputs from the amplifiers.