JP2010056177A - Transformer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transformer which is easy to manufacture and compact, and has high efficiency. <P>SOLUTION: The transformer includes: a coil portion 110 comprising a primary-side conductor 11 formed on a first ferrite substrate (first substrate) 1 and constituting a primary coil, and a secondary-side conductor 21 formed on a second ferrite substrate (second substrate) 2 to overlap part of the primary-side conductor 11 in plan view and constituting a secondary coil; an insulating layer 3 insulating the primary-side conductor 11 and secondary-side conductor 21; and a magnetic material layer 4 formed in a region where the insulating layer 3 is not formed between the first ferrite substrate 1 and second ferrite substrate 2. Then, the primary-side conductor 11 and secondary-side conductor 21 are both formed in an open loop shape zigzagging in plan view. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transformer used for power conversion or insulation in a switching power supply or the like.

  Conventionally, as shown in FIG. 10A, a coil block 111 ′ having primary conductors 11a ′ and 11b ′ (see FIG. 10B) as primary coils and a secondary conductor 21 ′ as a secondary coil. A thin transformer is proposed in which a coil block 111 ′ is sandwiched between a pair of magnetic core portions 51 ′ and 51 ′ from both sides in the thickness direction (see Patent Document 1).

  Here, the above-described thin transformer is manufactured as follows.

  First, a substrate 33 'formed of a flexible insulating material is prepared. Here, the substrate 33 ′ includes an elongated secondary insulator portion 32 ′ formed by continuously connecting five unit substrates 32 a ′ having a square shape in plan view in a row and a secondary insulator portion 32 ′. A primary-side insulator portion 31 ′ composed of two unit substrates 31a ′ each having a square shape in plan view, which is continuously and integrally connected to each of the second unit substrates 32a ′ from both ends.

  Next, a through hole 3a 'is formed in the center of each unit substrate 31a', 32a 'constituting the substrate 33'. Then, spiral primary conductors 11a ′ and 11b ′ are formed around the through hole 3a ′ of the unit substrate 31a ′ on the one surface side of the primary insulator 31 ′ constituting a part of the substrate 33 ′. A plurality of unit substrates 32a ′ constituting the secondary insulator part 32 ′ are formed along the longitudinal direction on one surface side of the secondary insulator part 32 ′ constituting a part of the substrate 33 ′. The secondary conductor 21 ′ is formed in a meandering manner between the through holes 3a ′ (see FIG. 10B).

  Then, after the two unit substrates 31a ′ are superimposed on the unit substrate 32a ′ by bending the substrate 33 ′ at the boundary between the unit substrates 31a ′ and 32a ′ (the one-dot chain line in FIG. 10B), FIG. As shown in FIG. 5, the coil block 111 ′ is formed by bending at the boundary between the unit substrates 31a ′ and 32a ′ (the chain line in FIG. 10B).

Subsequently, the coil block 111 ′ is sandwiched between the pair of magnetic core portions 51 ′ and 51 ′ from both sides in the thickness direction of the coil block 111 ′, whereby the thin transformer shown in FIG. 10A is manufactured. Here, the magnetic core portion 51 ′ is formed with a protrusion 51 a ′ inserted in the through hole 3 a ′ formed in the unit substrate 31 a ′ and the unit substrate 32 a ′ at the center (FIG. 10C). reference).
Registered Utility Model No. 25222263

  By the way, in the thin transformer described in Patent Document 1, primary conductors 11a ′ and 11b are formed by spirally forming primary conductors 11a ′ and 11b ′ on the one surface side of the primary insulator portion 31 ′. By increasing the number of turns of ', the inductances of the primary side conductors 11a' and 11b 'are increased. Accordingly, either one of both end portions of the primary side conductors 11a ′ and 11b ′ is located in the peripheral portion of the through hole 3a ′ formed around the primary side conductors 11a ′ and 11b ′, and the through hole 3a. The primary side conductors 11a ′ and 11b ′ are connected to the wirings connected to the input terminals and the like provided around the primary side conductors 11a ′ and 11b ′ from the ends of the primary side conductors 11a ′ and 11b ′ located in the periphery of It is necessary to cross in the thickness direction of the primary-side insulator portion 31 ′, and it is necessary to separately provide a structure for pulling out the wires from the primary-side conductors 11a ′ and 11b ′ while insulating the wiring from the primary-side conductors 11a ′ and 11b ′. Because of this, production was relatively difficult.

  The present invention has been made in view of the above-mentioned reasons, and an object thereof is to provide a transformer that is easy to manufacture and that is small and highly efficient.

  In order to achieve the above object, the first aspect of the present invention provides a first substrate and a second substrate in which one surface in the thickness direction is arranged opposite to each other, and a plane on the one surface of the first substrate. A primary conductor formed in a region overlapping with the second substrate in a view, and a portion of the primary conductor formed in a region overlapping with the first substrate in a plan view on the one surface of the second substrate in a plan view And two input terminals formed in a region other than a region overlapping the second substrate on the one surface of the first substrate and connected to both ends of the primary conductor via wirings Two output terminals formed in a region other than the region overlapping the first substrate on the one surface of the second substrate and connected to both ends of the secondary-side conductor via wiring, the first substrate and the first substrate Primary coil and secondary side consisting of primary side conductors between two substrates An insulating layer that is formed around a coil portion composed of a body secondary coil and insulates the primary side conductor and the secondary side conductor; and a coil portion between the first substrate and the second substrate, and And a magnetic layer formed in a region where the insulating layer is not formed, and both the primary side conductor and the secondary side conductor are formed in an open loop shape meandering in a plan view.

  According to this invention, the primary side conductor is formed in an open loop shape meandering on the one surface side of the first substrate, so that the inductance can be increased without forming the primary side conductor in a spiral shape. Because it is possible, there is no need to cross the wiring connecting from the end of the primary side conductor to the input terminal with the primary side conductor, and the secondary side conductor is also formed in an open loop shape meandering on the one surface side of the second substrate As a result, the inductance can be increased without forming the secondary conductor in a spiral shape, so that the wiring connecting from the end of the secondary conductor to the output terminal intersects the secondary conductor. Since it is not necessary, it can be easily manufactured. Moreover, since a primary side conductor and an input terminal can be produced simultaneously on the one surface side of the first substrate, and a secondary conductor and an output terminal can be produced simultaneously on the one surface side of the second substrate. In addition, the number of manufacturing steps can be reduced, manufacturing can be easily performed, and manufacturing costs can be reduced. Furthermore, since both the primary side conductor and the secondary side conductor are formed in an open loop shape meandering in plan view, the spread of magnetic flux around the primary side conductor and the secondary side conductor can be suppressed. Therefore, a small and highly efficient transformer can be provided.

  According to a second aspect of the present invention, in the first aspect of the present invention, the magnetic layer is formed by separating the magnetic layers from each other within a plane perpendicular to the thickness direction of the first substrate and the second substrate. It is composed of a plurality of magnetic blocks made of a body.

  According to this invention, the magnetic layer is formed in a continuous and integrated manner in each region where the coil portion and the insulating layer are not formed between the first substrate and the second substrate. Compared with the case where the eddy current is consumed, the loss of eddy current consumed in the magnetic layer can be reduced, so that a highly efficient transformer can be provided.

  According to a third aspect of the present invention, in the second aspect of the present invention, the magnetic layer includes at least two types of the magnetic block having different areas in a plan view, and the primary side conductor and the secondary side conductor, The area of the planar view shape of the magnetic body block gradually decreases as the distance from the center of the magnetic block increases, and the area of the planar view shape of the magnetic body block disposed closest to the primary side conductor and the secondary side conductor is reduced. Further, the magnetic block is formed so as to have an area equal to or less than the area of the planar view shape of the magnetic block disposed in another place.

  According to this invention, since the eddy current loss consumed in the magnetic layer can be further reduced as compared with the case where the area of the magnetic block in plan view is uniform, a highly efficient transformer can be obtained. Can be provided.

  According to the first aspect of the present invention, it is possible to increase the inductance of the primary side conductor and the secondary side conductor without forming the primary side conductor and the secondary side conductor in a spiral shape. It is not necessary to cross the wiring connecting to the input terminal from the primary side conductor, and it is not necessary to cross the wiring connecting from the end of the secondary side conductor to the output terminal to the secondary side conductor. Can do. Moreover, since a primary side conductor and an input terminal can be produced simultaneously on the one surface side of the first substrate, and a secondary conductor and an output terminal can be produced simultaneously on the one surface side of the second substrate. The number of manufacturing steps can be reduced, the manufacturing process can be easily performed, and the manufacturing cost can be reduced. Furthermore, since the spread of the magnetic flux around the primary side conductor and the secondary side conductor can be suppressed, a small and highly efficient transformer can be provided.

(Embodiment 1)
Hereinafter, the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1B shows a cross section taken along line AA ′ in FIG.

  The transformer of the present embodiment includes a first ferrite substrate 1 as a first substrate, a second ferrite substrate 2 as a second substrate, and a primary coil formed on one surface of the first ferrite substrate 1. A primary side conductor 11, a secondary side conductor 21 that is a secondary coil formed on one surface of the second ferrite substrate 2, and an insulating layer 3 that insulates the primary side conductor 11 from the secondary side conductor 21. The coil portion 110 composed of the primary side conductor 11 and the secondary side conductor 21 between the first ferrite substrate 1 and the second ferrite substrate 2 and the magnetism formed in the region where the insulating layer 3 is not formed. A body layer 4. That is, as shown in FIG. 1B, the transformer of the present embodiment includes a first coil on both sides in the arrangement direction of the primary side conductor 11 that is a primary coil and the secondary side conductor 21 that is a secondary coil. The ferrite substrate 1 and the second ferrite substrate 2 are disposed, and the magnetic layer 4 is formed with the coil portion 110 and the insulating layer 3 between the first ferrite substrate 1 and the second ferrite substrate 2. It is formed in no area. Further, on the one surface of the first ferrite substrate 1, input terminals 12 connected to both ends of the primary conductor 11 via the wiring 13 are formed, and on the one surface of the second ferrite substrate 2. Are formed with output terminals 22 connected to both ends of the secondary conductor 21 via wiring (not shown).

  The first ferrite substrate 1 and the second ferrite substrate 2 are formed in a rectangular plate shape having a rectangular shape in plan view, and are arranged such that one surface in the thickness direction faces each other. Further, the second ferrite substrate 2 is arranged in a form shifted from the first ferrite substrate 1 by a specified distance in the longitudinal direction of the first ferrite substrate 1. The first ferrite substrate 1 and the second ferrite substrate 2 are made of an insulating magnetic material such as Ni—Zn ferrite, for example.

  The primary-side conductor 11 as a primary coil is formed in a region overlapping the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1. On the other hand, the secondary-side conductor 21 that is a secondary coil has a part of the primary-side conductor 11 in plan view in a region overlapping the first ferrite substrate 1 in plan view on the one surface of the second ferrite substrate 2. It is formed in an overlapping form.

  By the way, in the transformer of this embodiment, the primary side conductor 11 as a primary coil and the secondary side conductor 21 as a secondary coil are formed in an open loop shape meandering in a plan view.

  The primary conductor 11 is formed in a rectangular region that overlaps the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1, and the first ferrite substrate 1 of the first ferrite substrate 1 is formed in the rectangular region. 2 formed so as to extend along two sides at both ends in the short direction and to be symmetrical with respect to the center line along the longitudinal direction of the first ferrite substrate 1 and to be spaced apart so that both ends face each other. Each of the U-shaped portions 11c, and one end portion of each U-shaped portion 11c extends through the wirings 13 and 13 extending along the longitudinal direction of the first ferrite substrate 1. , 12 and the other end portions are continuous via the second U-shaped portion 11d. On the other hand, the secondary conductor 21 is also formed in a region overlapping the first ferrite substrate 1 in plan view on the one surface of the second ferrite substrate 2, and the center along the longitudinal direction of the second ferrite substrate 2 Two first U-shaped portions (not shown) that are line-symmetric with respect to the line and are spaced apart from each other so that both ends thereof are opposed to each other, and one end portion of each U-shaped portion is The second ferrite substrate 2 is connected to the output terminals 22 and 22 via wires (not shown) extending along the longitudinal direction of the second ferrite substrate 2, and the other ends are second U-shaped portions (not shown). Z)).

  Here, the secondary side conductor 21 overlaps a part of the primary side conductor 11, that is, a part of the first U-shaped part 11c and a part of the second U-shaped part 11d in a plan view. Is formed. In addition, the primary side conductor 11 and the secondary side conductor 21 are formed, for example with Cu, W, Al, or the alloy which has these as a main component.

  The input terminal 12 is formed in a region other than the region overlapping the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1, and the output terminal 22 is formed on the second ferrite substrate 2. It is formed in a region other than a region overlapping the first ferrite substrate 1 in plan view on the one surface. Moreover, the primary side conductor 11 is connected to the input terminal 12 via the wiring 13, and the secondary side conductor 21 is connected to the output terminal 22b via the wiring (not shown). The input terminal 12 and the wiring 13 connected to the input terminal 12 are formed of the same material as the primary side conductor 11, and the output terminal 22 and the wiring connected to the output terminal 22 are the same material as the secondary side conductor 21. For example, Cu, W, Al, or an alloy containing these as a main component is used.

The insulating layer 3 includes a region overlapping the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1 and the first ferrite substrate in plan view on the one surface of the second ferrite substrate 2. 1 is formed around the coil portion 110 between the overlapping region. The insulating layer 3 is formed of SiO _2. In the present embodiment, SiO ₂ is used as the material of the insulating layer 3, but is not limited to this, and may be, for example, PSG.

  The magnetic layer 4 includes a region overlapping the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1 and a first view in plan view on the one surface of the second ferrite substrate 2. It is formed in a region where the coil part 110 and the insulating layer 3 are not formed between the region overlapping the ferrite substrate 1. The magnetic layer 4 is formed of a conductive magnetic material such as a Co-based alloy or an Fe-based alloy, for example, an alloy composed of Ni and Fe.

  Next, the manufacturing method of the transformer of this embodiment will be described with reference to FIG.

  First, a conductor forming step is performed in which the primary side conductor 11, the input terminal 12, and the wiring 13 are simultaneously formed on the one surface of the first ferrite substrate 1 (FIG. 3A) (FIG. 3B). In the conductor forming step, for example, a metal film serving as a basis for the primary side conductor 11, the input terminal 12, and the wiring 13 is formed on the one surface of the first ferrite substrate 1 by sputtering, vapor deposition, CVD, or the like. After the film formation, the primary side conductor 11, the input terminal 12, and the wiring 13 are formed by patterning the metal film using a photolithography technique and an etching technique.

After the conductor forming step, an insulating layer forming step of forming a primary insulating layer 31 made of a SiO ₂ layer so as to cover the primary conductor 11 on the one surface side of the first ferrite substrate 1 is performed (FIG. 3C). )). In the insulating layer forming step, from the viewpoint of improving the flatness of the surface of the first insulating layer 31, a CVD method using TEOS (tetraethoxysilane: Si (OC ₂ H ₅ ) ₄ ) as a source gas is employed.

  After the insulating layer forming step, an etching step for etching unnecessary portions of the primary insulating layer 31 is performed (FIG. 3D). In the etching step, for example, unnecessary portions of the primary insulating layer 31 are removed on the primary insulating layer 31 by using a photolithography technique and an etching technique.

  After the etching step, a magnetic layer forming step for forming the primary magnetic layer 41 made of a conductive magnetic material is performed. In the magnetic layer forming process, for example, after the magnetic layer 41 is formed on the one surface side of the first ferrite substrate 1 by sputtering, vapor deposition, CVD, or the like, the surface side of the magnetic layer 41 is subjected to CMP. The structure shown in FIG. 3E is obtained by flattening by means of, for example.

For the second ferrite substrate 2, similarly to the first ferrite substrate 1, a conductor forming step for forming the secondary side conductor 21, the output terminal 22 and the wiring at the same time, comprising the SiO ₂ layer and the primary side An insulating layer forming step for forming the secondary side insulating layer 32 constituting the insulating layer 3 together with the insulating layer 31, an etching step for removing unnecessary portions of the secondary side insulating layer 32 by etching, and a conductive magnetic material. In addition, the magnetic layer forming step for forming the secondary magnetic layer 42 constituting the magnetic layer 4 together with the primary magnetic layer 41 is sequentially performed to obtain the structure shown in FIG.

  Thereafter, the primary conductor 11 and the secondary conductor 21 are formed by performing a joining step of joining the one surface side of the first ferrite substrate 1 and the one surface side of the second ferrite substrate 2. 3 including a coil portion 110, an insulating layer 3 including a primary insulating layer 31 and a secondary insulating layer 32, and a magnetic layer 4 including a primary magnetic layer 41 and a secondary magnetic layer 42. The structure shown in (f) is obtained.

  Therefore, in this embodiment, since the primary side conductor 11 is formed in a meandering open loop shape, the inductance can be increased without forming the primary side conductor 11 in a spiral shape. The wiring 13 connecting the end of the conductor 11 to the input terminal 12 does not need to intersect with the primary side conductor 11, and the secondary side conductor 21 is also formed in a meandering open loop shape. Since the inductance can be increased without forming the conductor 21 in a spiral shape, a wiring (not shown) connected to the output terminal 22 from the end of the secondary conductor 21 intersects the secondary conductor 21. Since it is not necessary, it can be easily manufactured while improving the efficiency of the transformer. In the transformer of this embodiment, as described above, the primary conductor 11, the input terminal 12, and the wiring 13 can be simultaneously formed on the one surface side of the first ferrite substrate 1 in the conductor forming step. The manufacturing process can be reduced, and the secondary conductor 21, the input terminal 22 and the wiring can be simultaneously formed on the one surface side of the second ferrite substrate 2, thereby reducing the manufacturing process. It can be manufactured easily, and the manufacturing cost can be reduced.

  In the transformer manufacturing method of this embodiment, the conductor forming step, the insulating layer forming step, and the magnetic layer forming step can be simultaneously performed on the first ferrite substrate 1 and the second ferrite substrate 2. In other words, among the steps performed on the first ferrite substrate 1 and the second ferrite substrate 2, the manufacturing steps can be simplified by simultaneously performing the steps except the joining step. Can be produced.

  Next, the result of simulating the magnetic field distribution during operation of the transformer, which is an example of this embodiment, will be described.

  The finite element method was used for the simulation of the magnetic field distribution during the operation of the transformer of this example. Further, the simulation of the magnetic field distribution is performed by comparing the primary side conductor 11 as the primary coil and the secondary side conductor 21 as the secondary coil in a rectangular open loop shape (see FIG. 4A) and the primary. The embodiment (see FIG. 4B) in which the side conductor 11 and the secondary conductor 21 are formed in an open loop shape meandering was performed.

  In the comparative example and the example, as shown in FIG. 4, the length of the first ferrite substrate 1 is set to 8 mm, the length in the short direction is set to 5 mm, and the thickness is set to 500 μm. For the ferrite substrate 2, as in the first ferrite substrate 1, the length in the longitudinal direction is set to 8 mm, the length in the short direction is set to 5 mm, and the thickness is set to 500 μm.

  In the comparative example and the example, the primary conductor 11, the secondary conductor 21 and the wiring 13 are set to have a width of 0.5 mm and a thickness of 3 μm, and the input terminal 12 and the output terminal 22 are arranged in the longitudinal direction. The dimension is set to 2.5 mm and the dimension in the lateral direction is set to 2.15 mm.

  The primary side conductor 11 of the comparative example is rectangular in a square area in plan view that overlaps with the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1 along the four sides of the area. It is formed in an open loop shape, and the distance from four sides is 0.5 mm. On the other hand, the secondary conductor 21 of the comparative example has a thickness of 3 μm and a width of 0.5 mm, and is a plan view that overlaps the first ferrite substrate 1 in a plan view on the one surface of the second ferrite substrate 2. In the square area, a rectangular open loop is formed along the four sides of the area, and the distance from the four sides is 0.5 mm.

  The primary side conductor 11 of the embodiment has a square shape in plan view in which the two first U-shaped portions 11 c overlap the second ferrite substrate 2 in plan view on the one surface of the first ferrite substrate 1. The region is formed along the four sides of the region, and the distance from the four sides is 0.5 mm. Further, the two first U-shaped portions 11c constituting a part of the primary conductor 11 have a distance of 0.5 mm between one end portions continuous to the wiring 13 and a distance between the other end portions. 1.0 mm. In addition, the second U-shaped portion 11 d constituting a part of the primary conductor 11 is formed from the both ends in the longitudinal direction of the central portion formed along the short direction of the first ferrite substrate 1. The length of both legs extended toward the end is 2.5 mm, and the distance between the legs is 1.0 mm. On the other hand, the secondary-side conductor 21 of the embodiment is square in plan view in which two first U-shaped portions overlap the first ferrite substrate 1 in plan view on the one surface of the second ferrite substrate 2. It is formed along the four sides of the region, and the distance from the four sides is 0.5 mm. The two first U-shaped portions constituting a part of the secondary conductor 2 have a distance of 0.5 mm between the one end portions continuous to the wiring and a distance of 1 between the other end portions. 0.0 mm. Further, the second U-shaped part constituting a part of the secondary conductor 2 is formed from both ends in the longitudinal direction of the central part formed along the short direction of the second ferrite substrate 2 and the other The length of both legs extended toward the end is 2.5 mm, and the distance between the legs is 1.0 mm.

  Further, the primary side conductor 11 and the secondary side conductor 21 are made of copper, the relative permeability of the first ferrite substrate 1 and the second ferrite substrate 2 is 1000, and the relative permeability of the magnetic layer 4 is 100. did.

  The result of the simulation of the magnetic field distribution in the transformer of the above-described embodiment is shown in FIG. 5 together with the comparative example. FIG. 5 shows a case where the power supplied to the primary conductor 11 is 1 W. Here, considering that the magnitude of the magnetic flux density is proportional to the magnitude of the magnetic field, the embodiment (see FIG. 5B) is compared with the comparative example (see FIG. 5A) from FIG. Then, the spread of the magnetic flux around the coil part 110 was suppressed, and it was confirmed that the magnetic flux exists only in the vicinity of the coil part 110.

  On the other hand, the size of the first ferrite substrate 1 and the second ferrite substrate 2 is a range in which the magnetic flux spreads in consideration of shielding the magnetic field generated in the coil unit 110 so as not to leak outside the transformer. It must be large enough to cover. Therefore, in the comparative example, since the primary side conductor 11 and the secondary side conductor 21 are formed in a rectangular open loop shape in plan view, the spread of magnetic flux around the primary side conductor 11 and the secondary side conductor 21 is relatively long. It was large and it was difficult to reduce the size of the transformer. On the other hand, in the embodiment, as can be seen from the result of the above-described simulation of the magnetic field distribution, the spread of the magnetic flux around the coil portion 110 is suppressed, so that the transformer can be downsized.

  Next, analysis results of inductance, leakage inductance, and coupling degree in the transformer of the embodiment will be described. Here, the inductance represents the self-inductance of each of the primary side conductor 11 that is a primary coil and the secondary side conductor 21 that is a secondary coil, and the degree of coupling is the magnitude of mutual inductance between the primary side conductor 11 and the secondary side conductor 21. Represents. The leakage inductance represents an inductance caused by a magnetic flux that is linked only to the primary side conductor 11 and not linked to the secondary side conductor 21.

  Table 1 shows the inductance, leakage inductance, and degree of coupling in the comparative example and the example.

  The degree of coupling in the example was 1.0, as in the comparative example, and it was confirmed that a highly efficient transformer could be realized. Further, in the comparative example, the inductance of the primary side conductor 11 and the secondary side conductor 21 is 4.2 μH, whereas in the example, the inductance of the primary side conductor 11 and the secondary side conductor 21 is 4.7 μH. In addition, it was confirmed that the inductance of the primary side conductor 11 and the secondary side conductor 21 can be improved by adopting the example as compared with the comparative example. Further, it was confirmed that the leakage inductance was 0 μH in both the example and the comparative example.

After all, in the embodiment, the primary side conductor 11 and the secondary side conductor 21 are formed in a meandering open loop shape so that the primary side conductor 11 and the secondary side conductor 21 do not meander as in the comparative example. Compared with the case where it is formed in a loop shape, a small and highly efficient transformer can be realized by suppressing the spread of the magnetic flux around the coil part 110.
(Embodiment 2)
The basic configuration of the transformer of the present embodiment is substantially the same as that of the first embodiment. As shown in FIGS. 6 and 7, the magnetic layer 4 has the one surface orthogonal to the thickness direction of the first ferrite substrate 1. A primary side magnetic layer 41 (see FIG. 7) in which a plurality of magnetic blocks 4a are arranged separately from each other, and a second ferrite substrate 2 perpendicular to the thickness direction of the second ferrite substrate 2. In addition, the second magnetic layer 42 is different from the first ferrite substrate 1 in that the second magnetic layer 42 is formed by disposing a plurality of magnetic blocks 4a on the one surface facing each other. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The manufacturing method of the transformer of this embodiment is substantially the same as the manufacturing method of Embodiment 1, and only the magnetic layer forming process is different. Here, in the magnetic layer formation step, the magnetic layers 41 and 42 are formed on one surface side of each of the first ferrite substrate 1 and the second ferrite substrate 2 by, for example, a sputtering method, a vapor deposition method, or a CVD method. Later, by patterning the magnetic layers 41 and 42 using a photolithographic technique and an etching technique, the primary magnetic layer 41 and the secondary magnetic layer 42 composed of the plurality of magnetic blocks 4a described above are formed. Form.

Thus, the magnetic layer 4 is formed by disposing the plurality of magnetic blocks 4a separately from each other in a plane perpendicular to the thickness direction of the first ferrite substrate 1 and the second ferrite substrate 2, When the magnetic layer 4 is formed in a continuous and integrated manner in each region where the coil portion 110 and the insulating layer 3 are not formed between the first ferrite substrate 1 and the second ferrite substrate 2. In comparison, since eddy current loss consumed in the magnetic layer 4 can be reduced, a highly efficient transformer can be provided.
(Embodiment 3)
The basic configuration of the transformer of the present embodiment is substantially the same as that of the second embodiment. As shown in FIG. 8, the magnetic body layer 4 has two types of magnetic body blocks 4 a having different areas in plan view. As the primary conductor 11 and the secondary conductor 21 are approached, the area of the magnetic body block 4a in plan view is gradually reduced and is disposed closest to the primary conductor 11 and the secondary conductor 21. The difference is that the area of the planar view shape of the magnetic body block 4a is formed to be equal to or less than the area of the planar view shape of the magnetic body block 4a disposed at another location. In addition, about the component similar to Embodiment 2, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The manufacturing method of the transformer of the present embodiment is substantially the same as that of the second embodiment. In the magnetic layer forming step, the magnetic layer 41 composed of two kinds of magnetic blocks 4a having different areas in plan view. , 42 are different.

  Here, when power is supplied to the primary side conductor 11, the magnetic flux density around the primary side conductor 11 is the largest in the vicinity of the primary side conductor 11, and the distance from the primary side conductor 11 is as shown in FIG. It gets smaller when it gets bigger.

  Therefore, in the present embodiment, the magnetic block 4a constituting the magnetic layer 4 is disposed closest to the primary side conductor 11 having a large magnetic flux density during energization, and is disposed in the vicinity of the primary side conductor 11. The area of the planar view shape of the element disposed closest to the secondary side conductor 21 is formed to be equal to or smaller than the area of the planar view shape of the element disposed in another location. Therefore, the eddy current loss consumed in the magnetic layer 4 can be further reduced as compared with the case where the area of the magnetic block 4a in plan view is uniform.

The transformer of Embodiment 1 is shown, (a) is principal part sectional perspective view, (b) is principal part schematic sectional drawing. It is a schematic perspective view same as the above. It is principal process sectional drawing for demonstrating the manufacturing method same as the above. It is a schematic explanatory drawing of one Example same as the above. It is a figure which shows the result of the simulation of the magnetic field distribution at the time of operation | movement of one Example same as the above. FIG. 6 is a schematic plan view of a main part of a transformer according to a second embodiment. It is a principal part schematic perspective view of a transformer same as the above. FIG. 6 is a schematic plan view of a main part of a transformer according to a third embodiment. It is a figure which shows distribution of the magnetic flux density at the time of operation | movement same as the above. A conventional example is shown, (a) is a schematic perspective view after assembly, (b) is a schematic plan view showing one of developed components, and (c) is a schematic perspective view showing one of the components. It is a main process schematic perspective view for demonstrating the manufacturing method same as the above.

Explanation of symbols

1 First ferrite substrate (first substrate)
2 Second ferrite substrate (second substrate)
3 Insulating layer 4 Magnetic layer 4a Magnetic block 11 Primary side conductor 12 Input terminal 21 Secondary side conductor 22 Output terminal 31 Primary side insulating layer 32 Secondary side insulating layer 41 Primary side magnetic layer 42 Secondary side magnetic layer 110 Coil part

Claims (3)

  A first substrate and a second substrate having one surface in the thickness direction facing each other, and a primary side formed in a region overlapping the second substrate in plan view on the one surface of the first substrate A conductor, a secondary conductor formed in a region overlapping the first substrate in plan view on the one surface of the second substrate and partially overlapping the primary conductor in plan view, and the one of the first substrate. Two input terminals formed in a region other than the region overlapping the second substrate on the surface and connected to both ends of the primary-side conductor via wiring, and the first substrate on the one surface of the second substrate Two output terminals formed in a region other than the region overlapping with the second side conductor and connected to both ends of the secondary side conductor via wiring, and a primary coil made of a primary side conductor between the first substrate and the second substrate, Coil composed of secondary coil made of secondary conductor And an insulating layer that insulates the primary side conductor and the secondary side conductor, and a magnet formed between the first substrate and the second substrate in a region where the coil portion and the insulating layer are not formed. A transformer comprising: a body layer, wherein both a primary side conductor and a secondary side conductor are formed in an open loop shape meandering in a plan view.   2. The transformer according to claim 1, wherein the magnetic layer is composed of a plurality of magnetic blocks made of magnetic bodies arranged in a separated manner in a plane perpendicular to the thickness direction. The magnetic body layer has at least two types of areas having different planar shapes as the magnetic block, and the area of the planar shape of the magnetic block becomes closer to each of the primary conductor and the secondary conductor. The area of the planar view of the magnetic body block that is gradually reduced and is disposed closest to the primary side conductor and the secondary side conductor is a plane of the magnetic body block that is disposed elsewhere. 3. The transformer according to claim 2, wherein the transformer is formed so as to have an area of a visual shape or less.