Information
-
Patent Grant
-
6727794
-
Patent Number
6,727,794
-
Date Filed
Saturday, September 22, 200123 years ago
-
Date Issued
Tuesday, April 27, 200420 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Law Office of Donald D. Mondul
-
CPC
-
US Classifications
Field of Search
US
- 336 83
- 336 65
- 336 90
- 336 98
- 336 199
- 336 200
- 336 208
- 336 221
- 336 225
- 336 232
-
International Classifications
-
Abstract
An apparatus for establishing inductive coupling in an electrical circuit arranged on a plurality of dielectric substrates, the substrates being in a substantially abutting relationship and presenting a plurality of substantially parallel planar expanses, includes: (a) at least one first core segment situated in at least one first depression provided in a first planar expanse; (b) at least one second core segment situated in at least one second depression provided in a second planar expanse; (c) a selected second core segment is arranged for establishing magnetic flux coupling with a selected first core segment to establish a magnetic core structure; (d) a plurality of electrically conductive through-hole structures traverse at least one substrate; (e) a plurality of electrically conductive circuit traces are arrayed upon at least two of the planar expanses. The conductive traces and the through-hole structures cooperate to establish inductive coupling.
Description
BACKGROUND OF THE INVENTION
The present invention is directed to electrical inductive circuit elements, such as inductors and transformers, and especially to small electrical inductive circuit elements having a low profile that may be reliably and economically manufactured in production quantities.
Prior art inductive elements that require a magnetic core structure commonly provide a cutout aperture through a dielectric substrate for insertion of a ferromagnetic or other magnetic core structure. The core structure may already bear the required windings for effecting inductive coupling, or the required windings may be incorporated into circuit traces arrayed upon the substrate. There are problems with using such a structure, especially in applications where small inductive circuitry having a low profile is desired. Chief among the problems with such an approach are the room required to accommodate an inductive element and its supporting electrical circuitry. In addition, the large size of prior art inductive circuitry necessitates situating associated circuit elements a distance removed from the inductive element. Such physical separation among circuit elements introduces capacitance and inductance into the circuit as well as increased trace lengths, all of which may contribute to increased losses. Such an introduction of capacitive and inductive factors into circuitry is a problem in power supply output circuits as well as in any LC (inductance-capacitance) filter application; the increased capacitances and inductances reduce transient response of such circuits and increase losses.
An attempt to ameliorate the problems associated with assembling inductive circuit elements is described in U.S. Pat. No. 5,781,091 issued Jul. 14, 1998 to Krone, et al. for “Electronic Inductive Device and Method for Manufacturing”. Krone, et al. describe an assembly structure and process for manufacturing that structure that provides an inner board layer with an aperture. The apertured inner board layer is situated atop a laminate that includes an insulating layer and a copper foil layer. The insulating layer faces the inner board. The aperture is partially filled with a thin layer of fiber filled epoxy and a ferromagnetic core is installed within the aperture atop the fiber filled epoxy layer. Another layer of fiber filled epoxy is added on top of and within the center of the core completely covering the core and embedding the core in the fiber filled epoxy, an insulating material. A second laminate similar to the first laminate is then applied atop the inner board to complete a board stack, with the insulating layer of the second laminate facing the inner board.
Plated through-hole structures are provided traversing the board stack; circuit traces are created on outer faces of the board stack by etching the copper foil layers. The circuit traces are connected with the through-hole structures to establish electrical paths that encircle the core thereby establishing an inductive coupling circuit with the core.
One shortcoming of the Krone, et al. structure relates to the employment of fill material within the aperture that covers the core. The magnetic core is placed within an aperture that is filled with a material that is at least somewhat viscous at temperatures encountered during processing steps contemplated by Krone et al. As a consequence, the core is liable to “float” within the aperture during processing. The varied positioning that a core may assume during processing because of such an ability to float means that the through-hole structures required by Krone et al. for forming loops about the core for inductive coupling may not be placed with respect to the core to avoid intercepting the core. That is, the cores can float sufficiently that one may intercept the core while drilling or otherwise forming the through-holes. This placement precision limitation presents less of a problem for inductive devices that are sufficiently large. However, for inductors that are small enough to be useful in today's circuits for such applications as board mounted power supply products or the like, the size of the core is sufficiently small that manufacturing yields for such products will be too low to make the use of the Krone et al. structure an economically worthwhile approach. Further, the tolerances that are required for producing the Krone et al. structure are likely to be too large to permit fabrication of products small enough for use as board mounted power supply products.
There is a need for an improved structure for electrical inductive element and method for manufacture of the element that provides precision manufacturing of small power products with tightly controllable tolerances.
SUMMARY OF THE INVENTION
An apparatus for establishing inductive coupling in an electrical circuit arranged on a plurality of dielectric substrates, the plurality of dielectric substrates being in a substantially abutting relationship and presenting a plurality of substantially parallel planar expanses, includes: (a) at least one first core segment situated in at least one first depression provided in a first planar expanse of the plurality of planar expanses; (b) at least one second core segment situated in at least one second depression provided in a second planar expanse of the plurality of planar expanses; (c) a selected second core segment arranged for establishing magnetic flux coupling with a selected first core segment to establish a selected magnetic core structure; (d) a plurality of electrically conductive through-hole structures traversing at least one substrate of the plurality of substrates; (e) a plurality of electrically conductive circuit traces arrayed upon at least two planar expanses of the plurality of planar expanses. The plurality of conductive traces and the plurality of through-hole structures cooperate to effect establishing inductive coupling.
The method for manufacturing the apparatus produces an electrical circuit arranged on at least one dielectric substrate. The electrical circuit establishes inductive coupling with a magnetic core structure. The at least one substrate presents a plurality of substantially parallel planar expanses. The method includes the steps of: (a) providing at least one substrate; (b) creating a first depression in a first planar expanse of the plurality of planar expanses; (c) creating a second depression in a second planar expanse of the plurality of planar expanses; a portion of the second depression being substantially in register with a portion of the first depression; (d) situating a first core segment in the first depression; (e) situating a second core segment in the second depression; the first core segment effects magnetic flux coupling with the second core segment to establish a magnetic core structure; (f) providing a plurality of electrically conductive circuit traces arrayed on at least two of the planar expanses; (g) providing a plurality of electrically conductive through-hole structures traversing at least one substrate; (h) coupling the plurality of conductive traces and the plurality of through-hole structures to effect establishing inductive coupling.
It is, therefore, an object of the present invention to provide an apparatus for establishing inductive coupling in an electrical circuit, and a method for manufacture therefor, that facilitates precision manufacturing of small power products with tightly controllable tolerances.
Further objects and features of the present invention will be apparent from the following specification and claims when considered in connection with the accompanying drawings, in which like elements are labeled using like reference numerals in the various figures, illustrating the preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a perspective exploded view illustrating a prior art inductive circuit element poised for assembly.
FIG. 2
is a side view of the inductive circuit element of
FIG. 1
in an assembled orientation.
FIG. 3
is a top plan view of the preferred embodiment of an inductive circuit element according to the present invention.
FIG. 4
is a side view of the inductive element of FIG.
3
.
FIG. 5
is a perspective view of the preferred embodiment of a core segment for use with the present invention.
FIG. 6
is a simplified side view of the inductive circuit element illustrated in
FIG. 3
showing an alternate placement arrangement for magnetic core segments.
FIG. 7
is a simplified side view of the inductive circuit element illustrated in
FIG. 3
showing a second alternate placement arrangement for magnetic core segments.
FIG. 8
is a simplified side view of the inductive circuit element illustrated in
FIG. 3
showing a third alternate placement arrangement for magnetic core segments.
FIG. 9
is a plan view of a representative circuit layout illustrating an alternate structure for fixing position of a core segment in a product.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
For purposes of this description throughout, the term “magnetic” is considered to be substantially synonymous with the terms “ferrous”, “ferromagnetic”, and “magnetizable”.
FIG. 1
is a perspective exploded view illustrating a prior art inductive circuit element poised for assembly. In
FIG. 1
, an inductive circuit element
10
includes a printed wiring board substrate
12
, and ferrite elements
14
,
16
. Substrate
12
has an aperture
20
therethrough. Ferrite elements
14
,
16
are preferably substantially symmetric. Ferrite element
14
includes a pair of raised end portions
22
,
24
extending from a base portion
25
. Ferrite element
16
includes a pair of raised end portions
26
,
28
extending from a base portion
29
. Ferrite element
16
includes a center post
30
extending from base portion
25
in the same direction as end portions
22
,
24
extend. Ferrite element
14
has a similar center post extending from base portion
29
in the same direction as end portions
26
,
28
extend (not visible in FIG.
1
).
During assembly ferrite elements
14
,
16
are positioned together with substrate
12
between ferrite elements
14
,
16
. Center post
30
(and its mating center post extending from ferrite element
14
meet through aperture
20
. End portions
22
,
26
meet at a cutout
32
provided in substrate
12
. End portions
24
,
28
meet at a cutout
23
provided in substrate
12
.
A clip
40
may be provided to securely grippingly assemble substrate
12
with ferrite elements
14
,
16
. Other attachment mechanisms may be employed in assembling inductive circuit element
10
, such as adhesive between raised end portions
22
,
26
, between raised end portions
24
,
28
and between center post
30
and a similar center post on ferrite element
14
(not visible in FIG.
1
).
Windings (not shown in
FIG. 1
) may be arranged about ferrite elements
14
,
16
or arranged about center post
30
(and its mating center post extending from ferrite element
14
; not visible in
FIG. 1
) to establish inductive coupling with ferrite elements
14
,
16
. Windings may be embodied in a variety of structures (not shown in FIG.
1
). For example, windings may be embodied in a winding bundle nestled about center post
30
and its mating center post extending from ferrite element
14
. Another example of an embodiment of a winding structure for effecting inductive coupling with ferrite elements
14
,
16
is one or more circuit traces arranged on substrate
12
.
FIG. 2
is a side view of the inductive circuit element of
FIG. 1
in an assembled orientation. In
FIG. 2
, inductive circuit element
10
includes substrate
12
situated between ferrite elements
14
,
16
. Clip
40
holds substrate
12
, and ferrite elements
14
,
16
in a unitary package. Inductive circuit element
10
extends a thickness t measured across the maximum expanse from ferrite element
14
to ferrite element
16
. It is the thickness t that needs reduction in order that inductive circuit element
10
may be better employed in the increasingly compact products being required today. That is, reduction of thickness t makes inductive circuit element
10
a lower profile circuit element.
FIG. 3
is a top plan view of the preferred embodiment of an inductive circuit element according to the present invention. In
FIG. 3
, an inductive circuit element
50
includes a base member
52
and magnetic or ferromagnetic core segments
60
,
62
,
64
,
66
arrayed in base member
52
. Each of core segments
60
,
62
,
64
,
66
is a substantially U-shaped element having a base or bight section and a pair of legs extending from the base or bight member. Core segments may be configured to result in an “EI” core element, or an “EE” core element or another shape of core element. The U-shaped element formed by core segments
60
,
62
,
64
,
66
is described here by way of example and not by way of limitation. Thus, core segment
60
has a base or bight member
60
a
and legs
60
b
,
60
c
extending from base member
60
a
to leg ends
60
d
,
60
e
. Core segment
62
has a base or bight member
62
a
and legs
62
b
,
62
c
extending from base member
62
a
to leg ends
62
d
,
62
e
. Core segment
64
has a base or bight member
64
a
and legs
64
b
,
64
c
extending from base member
64
a
to leg ends
64
d
,
64
e
. Core segment
66
has a base or bight member
66
a
and legs
66
b
,
66
c
extending from base member
66
a
to leg ends
66
d
,
66
e
. Core segments
60
,
62
are situated appropriately with legs
60
b
,
62
b
in overlapping relationship and with legs
60
c
,
62
c
in overlapping relationship to establish magnetic flux coupling and cooperate to establish a ferromagnetic core structure
70
. Core segments
64
,
66
are situated appropriately with legs
64
b
,
66
b
in overlapping relationship and with legs
64
c
,
66
c
in overlapping relationship to establish magnetic flux coupling and cooperate to establish a ferromagnetic core structure
72
.
Electrically conductive through-hole structures
80
,
82
,
84
,
86
,
88
traverse base member
52
to provide electrical continuity through base member
52
. Circuit traces are arrayed on base member
52
to complete electrical circuit paths that cooperate with through-hole structures
80
,
82
,
84
,
86
,
88
and ferromagnetic core structures
70
,
72
in effecting inductive coupling. The inductive coupling that may be effected by such cooperation may establish an inductor structure, a transformer structure or another inductively coupled structure.
FIG. 3
(and
FIG. 4
) illustrates an inductive coupling embodied in a 2:1 transformer structure. Thus, a circuit trace
90
representing, for example, a primary turn in a transformer includes a trace segment
90
a
on the top side of base member
52
from a start locus
91
to connect with through-hole structure
82
. Such connection (and other similar connections or couplings described herein) are preferably effected using solder coupling; other electrical coupling technologies may also be employed. A second trace segment
90
b
on the bottom side of base member
52
couples through-hole structure
82
with through-hole structure
84
. Another trace segment
90
c
on the top side of base member
52
couples through-hole structure
84
with through-hole structure
88
. Yet another trace segment
90
d
on the bottom side of base member
52
couples through-hole structure
88
with an end locus
93
.
In such manner, there is a continuous electrical path established by circuit trace
90
in cooperation with through-hole structures
82
,
84
,
88
to establish a single turn of an electrical conductor through ferromagnetic core structure
70
and establish a single turn of an electrical conductor through ferromagnetic core structure
72
. Electrical connection may be made with start locus
91
and end locus
93
to include primary circuit trace
90
in an external electrical circuit (not shown in FIG.
3
).
A second circuit trace
92
representing, for example, secondary turns in a transformer includes a trace segment
92
a
on the top side of base member
52
from a start locus
95
to connect with trace segments
92
b
,
92
c
. Trace segment
92
b
on the top side of base member
52
connects trace segment
92
a
with through-hole structure
86
. Trace segment
92
c
on the top side of base member
52
connects trace segment
92
a
with through-hole structure
80
. A trace segment
92
d
on the bottom side of base member
52
couples through-hole structures
80
,
86
with an end locus
97
.
In such manner, there is a continuous electrical path established by circuit trace
92
in cooperation with through-hole structures
80
,
86
to establish two parallel single turns of an electrical conductor through ferromagnetic core structures
70
,
72
. Electrical connection may be made with start locus
95
and end locus
97
to include secondary circuit trace
92
in an external electrical circuit (not shown in FIG.
4
).
FIG. 4
is a side view of the inductive element of FIG.
3
. In
FIG. 4
, inductive circuit element
50
is arrayed in a base member
52
. Base member
52
includes a top substrate
53
and a bottom substrate
55
. Through-hole structures
80
,
82
,
84
,
86
,
88
traverse top substrate
53
and bottom substrate
55
to provide electrical continuity among circuit traces
90
,
92
as described by way of example in the exemplary circuit trace structure illustrated in
FIG. 3
(only portions of circuit traces
90
,
92
are visible in FIG.
4
).
Depressions
40
,
44
are established in top substrate
53
appropriately dimensioned to nestlingly receive magnetic core segments
60
,
64
. Depressions
42
,
46
are established in bottom substrate
55
appropriately dimensioned to nestlingly receive magnetic core segments
62
,
66
. Depressions
40
,
44
partially extend into top substrate
53
leaving a distance d
1
separation from depressions
40
,
42
to the lower boundary
54
of top substrate
53
. Depressions
42
,
46
partially extend into bottom substrate
55
leaving a distance d
2
separation from depressions
42
,
46
to the lower boundary
56
of bottom substrate
55
. By such an arrangement a separation distance d
1
is established between depressions
40
,
42
and between depressions
44
,
46
, so that a similar separation distance d
1
is established between magnetic core segments
60
,
62
and between magnetic core segments
64
,
66
. Separation distance d
1
is preferably established at a dimension to permit magnetic flux coupling between magnetic core segments
60
,
62
and between magnetic core segments
64
,
66
.
Magnetic core segments
60
,
62
,
64
,
66
have respective upper faces
73
,
75
,
77
,
79
. Preferably, magnetic core segments
60
,
62
,
64
,
66
are proportioned to be substantially fully received within respective depressions
40
,
42
,
44
,
46
so that magnetic core segments
60
,
62
,
64
,
66
present respective upper faces
73
,
75
,
77
,
79
substantially flush with associated substrates
53
,
55
.
FIG. 5
is a perspective view of the preferred embodiment of a core segment for use with the present invention. In
FIG. 5
, a magnetic core segment
560
is preferably a substantially planar ferrous piece having a base or bight member
560
a
and legs
560
b
,
560
c
extending from base member
560
a
to leg ends
560
d
,
560
e
. In its preferred embodiment magnetic core segment
560
is a pliable magnetic material. Examples of such pliable magnetic material include magnetically loaded paste materials and magnetically loaded composite sheet materials, such as ferrite polymer composite materials. The magnetic materials of which magnetic core segment
560
is made may include a distributed air gap within the material. Such a distributed air gap construction facilitates establishing a plurality of magnetic core segments
560
(see, for example, magnetic core segments
60
,
62
and magnetic core segments
64
,
66
;
FIGS. 3 and 4
) to provide a magnetic reluctance path on one layer (e.g., top substrate
53
;
FIG. 4
) that is transferred to another layer (e.g., bottom substrate
55
; FIG.
4
). By making magnetic core segments
560
using magnetic material having a distributed air gap, there need not be an air gap provided in inter-layer transitions of a magnetic element. By way of example, magnetic core segments
60
,
62
(
FIGS. 3 and 4
) could be situated in facing abutting relationship at lower boundary
56
of top substrate
53
, if desired, if magnetic core segments
60
,
62
are manufactured using such a material having a distributed air gap.
FIG. 6
is a simplified side view of the inductive circuit element illustrated in
FIG. 3
showing an alternate placement arrangement for magnetic core segments. In
FIG. 6
, an inductive circuit element
650
is arrayed in a base member
652
. Base member
652
includes a top substrate
653
, a bottom substrate
655
and a middle substrate
657
.
Depressions
640
,
644
are established in top substrate
653
appropriately dimensioned to nestlingly receive magnetic core segments (e.g., magnetic core segments
60
,
64
; FIG.
3
). Depressions
642
,
646
are established in bottom substrate
655
appropriately dimensioned to nestlingly receive magnetic core segments (e.g., magnetic core segments
62
,
66
; FIG.
3
). Depressions
640
,
644
partially extend into top substrate
653
leaving a distance d
1
, separation from depressions
640
,
644
to the lower boundary
654
of top substrate
653
. Depressions
642
,
646
partially extend into bottom substrate
655
leaving a distance d
2
separation from depressions
642
,
646
to the lower boundary
656
of bottom substrate
655
. Middle substrate
657
has a thickness d
3
. By such an arrangement a separation distance (d
1
+d
3
) is established between depressions
640
,
642
and between depressions
644
,
646
, so that a similar separation distance (d
1
+d
3
) is established between magnetic core segments situated within depressions
640
,
642
and between magnetic core segments situated within depressions
644
,
646
. Separation distance (d
1
+d
3
) is preferably established at a dimension to permit magnetic flux coupling between magnetic core segments situated within depressions
640
,
642
and between magnetic core segments situated within depressions
644
,
646
.
FIG. 7
is a simplified side view of the inductive circuit element illustrated in
FIG. 3
showing a second alternate placement arrangement for magnetic core segments. In
FIG. 7
, an inductive circuit element
750
is arrayed in a base member
752
. Base member
752
is a single substrate having a top face
771
and a bottom face
773
.
Depressions
740
,
744
are established in top face
771
appropriately dimensioned to nestlingly receive magnetic core segments (e.g., magnetic core segments
60
,
64
; FIG.
3
). Depressions
742
,
746
are established in bottom face
773
appropriately dimensioned to nestlingly receive magnetic core segments (e.g., magnetic core segments
62
,
66
; FIG.
3
). Depressions
740
,
744
partially extend into base member
752
from top face
771
. Depressions
742
,
746
partially extend into base member
752
from bottom face
773
. A separation distance d
1
is thereby established between from depressions
740
,
742
and between depressions
744
,
746
. Separation distance d
1
is preferably established at a dimension to permit magnetic flux coupling between magnetic core segments situated within depressions
740
,
742
and between magnetic core segments situated within depressions
744
,
746
.
The advantages of manufacturing an inductive circuit element according to the structure and method disclosed in this specification include having an inductive circuit element with its magnetic core elements situated within its substrate or substrates. Thus there is provided a low profile device. In fact, the resulting device has no profile other than the substrates and other items carried thereon, such as capacitors, circuit traces and other similar electrical or electronic components. The bulky profile presented by prior art devices is eliminated.
An additional benefit of the structure and method of the present invention is that there is more “real estate” made available for circuit traces, components and other items. That is more area is available using the structure or method of the present invention than is available using prior art approaches for placing circuit parts and connecting them to create a product. This advantageous result is achieved principally because the “real estate” in the vicinity of the core elements is substantially fully available for carrying circuitry.
The availability of areas proximate to the core elements is also important because it facilitates locating components used in connection with or in support of the inductive circuit element in locations closely adjacent with the core elements. For example, when the inductive circuit element of the present invention is used in an LC (inductive capacitive) filter application, the additional inductances, capacitances and resistance that may occur because of supporting components and circuit traces necessary to connect the various components are reduced. Such “stray” inductances, capacitances and resistance are significantly reduced by using the structure or method of the present invention, and transient response of the circuit is improved because of the nearly adjacent location of components and the core of the inductive circuit element.
The advantages of low profile and available real estate are also available when the present invention is used for manufacturing an inductive circuit element as a module for use in another circuit rather than integrally created with a circuit. Either employment of the structure or method of the present invention yields similar advantages that include lower profile and fewer sources of “stray” inductance and capacitance.
FIG. 8
is a simplified side view of the inductive circuit element illustrated in
FIG. 3
showing a third alternate placement arrangement for magnetic core segments. In
FIG. 8
, an inductive circuit element
850
is arrayed in a base member
852
. Base member
852
is a single substrate having a top face
871
and a bottom face
873
.
Depressions
840
,
842
,
844
,
846
are established in top face
871
appropriately dimensioned to nestlingly receive magnetic core segments (e.g., magnetic core segments
60
,
64
; FIG.
3
). Depressions
840
,
842
,
844
,
846
partially extend into base member
852
from top face
871
. A separation distance d
1
is established between depressions
840
,
842
. Separation distance d
1
is preferably established at a dimension to permit magnetic flux coupling between magnetic core segments situated within depressions
840
,
842
. A separation distance d
2
is established between depressions
844
,
846
. Separation distance d
2
is preferably established at a dimension to permit magnetic flux coupling between magnetic core segments situated within depressions
844
,
846
.
FIG. 9
is a plan view of a representative circuit layout illustrating an alternate structure for fixing position of a core segment in a product. In
FIG. 9
, a product
900
includes a plurality of etched lands
902
,
904
,
906
,
908
on a substrate
910
. Lands
902
,
904
,
906
,
908
are preferably copper lands. Lands
902
,
904
,
906
,
908
extend substantially perpendicularly from substrate
910
a distance sufficient to establish a thickness of lands
902
,
904
,
906
,
908
(not shown in FIG.
9
). The thickness of lands
902
,
904
,
906
,
908
thus established are of sufficient dimension to form a fixture
912
for nestlingly fixing a core segment
914
against lateral movement in directions generally parallel with substrate
910
. Preferably the thickness of lands
902
,
904
,
906
,
908
is about one-half the thickness of core segment
914
, or greater. Through-holes
916
,
918
,
920
may be provided configured, for example, for solder-filling to contribute to establishing loops about core segment
914
.
It is to be understood that, while the detailed drawings and specific examples given describe preferred embodiments of the invention, they are for the purpose of illustration only, that the apparatus and method of the invention are not limited to the precise details and conditions disclosed and that various changes may be made therein without departing from the spirit of the invention which is defined by the following
Claims
- 1. An apparatus for effecting inductive coupling with a ferromagnetic core structure; the apparatus comprising:(a) at least one substrate of a dielectric material; at least one selected substrate of said at least one substrate being configured with at least one fixture; each said at least one fixture being dimensioned for receiving a respective core segment; a core segment sets including at least two said core segments is received by said at least one fixture and separated by a volume of said dielectric material; said core segment sets being arranged for establishing magnetic flux coupling among said at least two core segments to establish said ferromagnetic core structure when said at least one substrate is in an assembled orientation with said ferromagnetic core structure and said at least one substrate arranged in a unitary structural relationship; (b) a plurality of electrically conductive circuit traces; said plurality of circuit traces being arrayed upon at least two predetermined surfaces of said at least one substrate; (c) a plurality of electrically conductive through-hole structures; said plurality of through-hole structures traversing said at least one selected substrate; said plurality of circuit traces and said plurality of through-hole structures cooperating to establish said inductive coupling when said at least one substrate is in said assembled orientation.
- 2. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 1 wherein said at least one substrate is a plurality of substrates, and wherein each respective substrate of said plurality of substrates is substantially planar, and wherein said assembled orientation abuttingly situates said plurality of substrates substantially in parallel in said unitary structural relationship.
- 3. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 1 wherein said inductive coupling establishes an inductor element including said ferromagnetic core structure.
- 4. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 1 wherein said inductive coupling establishes a transformer element including said ferromagnetic core structure.
- 5. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 1 wherein each said respective core segment is embodied in a pliable magnetic material.
- 6. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 5 wherein said pliable magnetic material is a magnetically loaded paste material.
- 7. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 5 wherein said pliable magnetic material is a magnetically loaded polymer composite sheet material.
- 8. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 2 wherein said inductive coupling establishes an inductor element including said ferromagnetic core structure.
- 9. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 2 wherein said inductive coupling establishes a transformer element including said ferromagnetic core structure.
- 10. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 2 wherein each said respective core segment is embodied in a pliable magnetic material.
- 11. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 10 wherein said pliable magnetic material is a magnetically loaded paste material.
- 12. An apparatus for effecting inductive coupling with a ferromagnetic core structure as recited in claim 10 wherein said pliable magnetic material is a magnetically loaded polymer composite sheet material.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
5430613 |
Hastings et al. |
Jul 1995 |
A |
5781091 |
Krone et al. |
Jul 1998 |
A |
5959846 |
Noguchi et al. |
Sep 1999 |
A |
Foreign Referenced Citations (1)
Number |
Date |
Country |
58-53807 |
Mar 1983 |
JP |