Integrated current sensor with magnetic flux concentrators

Patent metadata

Field	Value
Publication number	US-2022018879-A1
Application number	US-202016932299-A
Country	US
Kind code	A1
Filing date	Jul 17, 2020
Priority date	Jul 17, 2020
Publication date	Jan 20, 2022
Grant date	—

Abstract

A packaged current sensor includes a lead frame, an integrated circuit, an isolation spacer, a first magnetic concentrator, and a second magnetic concentrator. The lead frame includes a conductor. The isolation spacer is between the lead frame and the integrated circuit. The first magnetic concentrator is aligned with the conductor. The second magnetic concentrator is aligned with the conductor.

First claim

What is claimed is:

1 . A packaged current sensor, comprising:
a lead frame comprising a conductor; an integrated circuit; an isolation spacer between the lead frame and the integrated circuit; and a magnetic concentrator aligned with the conductor.

2 . The packaged current sensor of claim 1 , wherein the integrated circuit comprises a Hall effect sensor aligned with the magnetic concentrator.

3 . The packaged integrated circuit of claim 2 , wherein:
the magnetic concentrator is a first magnetic concentrator; the packaged integrated circuit comprises a second magnetic concentrator; and the Hall effect sensor is between the first magnetic concentrator and the second magnetic concentrator.

4 . The packaged current sensor of claim 3 , wherein the Hall effect sensor overlaps an edge of the first magnetic concentrator and an edge of the second magnetic concentrator.

5 . The packaged current sensor of claim 1 wherein the integrated circuit comprises:
a first Hall effect sensor aligned with an edge of the magnetic concentrator; and
a second Hall effect sensor aligned with the edge of the magnetic concentrator opposite the first Hall effect sensor.

6 . The packaged current sensor of claim 5 , wherein:
the magnetic concentrator is a first magnetic concentrator; the packaged integrated circuit comprises a second magnetic concentrator; and the integrated circuit comprises:
a third Hall effect sensor aligned with an edge of the second magnetic concentrator; and
a fourth Hall effect sensor aligned with the edge of the second magnetic concentrator opposite the third Hall effect sensor.

7 . The packaged current sensor of claim 6 , wherein:
the conductor comprises:
a current input leg; and
a current output leg; and
the first magnetic concentrator is aligned with the current input leg; and the second magnetic concentrator is aligned with the current output leg.

8 . The packaged current sensor of claim 1 , wherein the first magnetic concentrator and the second magnetic concentrator are electroplated onto the integrated circuit.

9 . The packaged current sensor of claim 1 , wherein the first magnetic concentrator and the second magnetic concentrator comprise a circular disk of soft magnetic material or a polygonal disk of soft magnetic material.

10 . A current sensor, comprising:
a lead frame comprising a conductor, wherein the conductor comprises:
a current input segment; and
a current output segment;
an integrated circuit comprising a Hall effect sensor; an isolation spacer between the lead frame and the integrated circuit; a first magnetic concentrator aligned with the current input segment and overlapping the Hall effect sensor; and a second magnetic concentrator aligned with the current output segment.

11 . The current sensor of claim 10 , wherein the second magnetic concentrator overlaps the Hall effect sensor.

12 . The current sensor of claim 10 , wherein:
the Hall effect sensor is a first Hall effect sensor; and the integrated circuit comprises a second Hall effect sensor overlapping an edge of the first magnetic concentrator opposite the first Hall effect sensor.

13 . The current sensor of claim 12 , wherein:
the integrated circuit comprises a third Hall effect sensor overlapping an edge of the second magnetic concentrator.

14 . The current sensor of claim 13 , wherein:
the integrated circuit comprises a fourth Hall effect sensor overlapping an edge of the second magnetic concentrator opposite the third Hall effect sensor.

15 . The current sensor of claim 10 , wherein the first magnetic concentrator and the second magnetic concentrator comprise a circular disk of soft magnetic material.

16 . The current sensor of claim 10 , wherein the first magnetic concentrator and the second magnetic concentrator comprise a polygonal disk of soft magnetic material.

17 . A current sensor, comprising:
a lead frame comprising a conductor, wherein the conductor comprises:
a current input segment; and
a current output segment;
an integrated circuit comprising:
a first Hall effect sensor;
a second Hall effect sensor;
a third Hall effect sensor; and
a fourth Hall effect sensor; and
an isolation spacer between the lead frame and the integrated circuit; and a first magnetic concentrator and a second magnetic concentrator formed as a metal layer on the integrated circuit, the first magnetic concentrator overlapping the current input segment, the first Hall effect sensor, and the second Hall effect sensor, and the second magnetic concentrator overlapping the current output segment, the third Hall effect sensor, and the fourth Hall effect sensor.

18 . The current sensor of claim 17 , wherein:
the first Hall effect sensor overlaps an edge of the first magnetic concentrator; and the second Hall effect sensor overlaps the edge of the first magnetic concentrator opposite the first Hall effect sensor.

19 . The current sensor of claim 17 , wherein:
the third Hall effect sensor overlaps an edge of the second magnetic concentrator; and the fourth Hall effect sensor overlaps the edge of the second magnetic concentrator opposite the first Hall effect sensor.

20 . The current sensor of claim 17 , wherein the first magnetic concentrator and the second magnetic concentrator comprise a circular magnetic disk or a polygonal magnetic disk.

Assignees

• Texas Instruments Inc

Inventors

• Lee Dok Won
• Bito Jo
• Green Keith Ryan

Classifications

• H10W70/458

  of insulating layers on leadframes · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W90/736

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10N59/00

  Integrated devices, or assemblies of multiple devices, comprising at least one galvanomagnetic or Hall-effect element covered by groups H10N50/00 - H10N52/00 (MRAM devices H10B61/00) · CPC title