Transformer

Abstract

The present invention relates to a transformer in which parasitic capacitance is reduced by dividing a second conductive pattern, the transformer including: a core unit including an upper core and a lower core; a first conductive pattern substrate printed with a first conductive pattern forming at least one turn around a through-hole through which a center leg of the core unit passes; and a second conductive pattern substrate that is printed with the second conductive pattern composed of a plurality of metal plates divided on one plane and is disposed on at least one of the upper portion or the lower portion of the first conductive pattern substrate. By dividing a secondary coil pattern into multiple parts and disposing the multiple parts on a single substrate and connecting the multiple parts using a center tap, it is possible to reduce the inter-winding capacitance between a primary coil and secondary coils and the capacitance (parasitic capacitance) between the secondary coils, and lower the temperature of the generated heat while designing the stack height of the secondary coils to be low.

Description

Transformers

[0001] The present invention relates to a transformer, and more particularly, to a transformer capable of reducing parasitic capacitance by dividing a second conductive pattern.

[0002] Magnetic elements, also known as magnetic coupling devices, include inductors, transformers, and EMI filters consisting of inductors and capacitors. These magnetic elements can be mounted on various types of circuit boards, such as the board of a power supply unit (PSU).

[0003] Recently, in line with the trend toward slimmer electronic products, slim magnetic elements in which the coils that make up the magnetic elements have the form of a printed circuit board (PCB) and share the middle part of the magnetic core are becoming popular.

[0004] In the case of a transformer, the core portion may include a primary side and a secondary side coil portion. The core portion may include an upper core and a lower core, and a coil portion in the form of a PCB as shown in Fig. 1 is placed between the upper core and the lower core.

[0005] However, in the coil section, the conductive patterns of the primary coil and the secondary coil are laminated to perform the function of the coil, but these conductive patterns have a problem that resistance may increase due to the skin effect or greater loss may occur due to the proximity effect between the conductive patterns. This problem can be solved to some extent by increasing the thickness of the conductive pattern, but since the conductive pattern is generally formed of copper, an increase in thickness leads to an increase in the unit price of the magnetic element, and the thickness of the pattern that can be formed on the substrate is also limited.

[0006] The present invention aims to provide a transformer capable of increasing efficiency by reducing leakage inductance.

[0007] Another object of the present invention is to provide a transformer capable of reducing parasitic capacitance and heat generation.

[0008] In order to achieve these objects, a transformer according to the present invention comprises: a core portion including an upper core and a lower core; a coil portion at least partially disposed inside the core portion; wherein the coil portion comprises a first conductive pattern substrate including a first through-hole formed so as to allow a middle foot of the core portion to pass through, and a first conductive pattern having at least one turn formed to surround the first through-hole; and a second conductive pattern substrate including a plurality of second conductive patterns including a second through-hole formed so as to allow a middle foot of the core portion to pass through, and at least one turn formed to surround the second through-hole, wherein the second conductive pattern substrate is disposed at at least one position among the upper and lower portions of the first conductive pattern substrate.

[0009] In a transformer according to the present invention, the second conductive pattern comprises a first metal plate pattern (NS1); and a second metal plate pattern (NS2) spaced apart from the first metal plate pattern (NS1).

[0010] In the transformer according to the present invention, the plurality of second metal plate patterns (NS2) include a second-first metal plate pattern (NS2-1) arranged between the first metal plate pattern (NS1) and the second through hole; and a second-second metal plate pattern (NS2-2) arranged spaced apart from the second-first metal plate pattern (NS2-1).

[0011] In the transformer according to the present invention, the first conductive pattern substrate includes a first connection pattern (CP1) formed around the first conductive pattern, and the first connection pattern (CP1) includes a first via hole and a second via hole.

[0012] In the transformer according to the present invention, each of the plurality of second metal plate patterns (NS2) includes a via hole, and the via hole of the second-first metal plate pattern (NS2-1) is electrically connected to the first via hole, and the via hole of the second-second metal plate pattern (NS2-2) is electrically connected to the second via hole.

[0013] In the transformer according to the present invention, the first conductive pattern substrate comprises: an upper primary substrate having a first wire pattern formed with a center tab formed on one side; and a lower primary substrate disposed below the upper primary substrate and having a second wire pattern formed in a shape symmetrical to the first wire pattern.

[0014] In the transformer according to the present invention, the second conductive pattern substrate comprises a plurality of substrates, including an upper secondary substrate disposed on top of the first conductive pattern substrate and a lower secondary substrate disposed on a lower side of the first conductive pattern substrate and including a plurality of second conductive patterns.

[0015] In the transformer according to the present invention, the plurality of second conductive patterns of the lower secondary substrate include a third metal plate pattern (NS3) and a plurality of fourth metal plate patterns (NS4) spaced apart from each other with the third metal plate pattern (NS3) interposed therebetween.

[0016] In the transformer according to the present invention, the 4-1 metal plate pattern and the 4-2 metal plate pattern are electrically connected to each other.

[0017] In the transformer according to the present invention, the lower primary substrate includes a second connection pattern (CP2) formed around the second wire pattern, and the second connection pattern (CP2) includes a third via hole and a fourth via hole.

[0018] In the transformer according to the present invention, the 4-1 metal plate pattern and the 4-2 metal plate pattern each include a via hole, and the via hole of the 4-1 metal plate pattern is electrically connected to the third via hole, and the via hole of the 4-2 metal plate pattern is electrically connected to the fourth via hole.

[0019] The transformer according to the present invention may further include a conductive line disposed on the second conductive pattern substrate and electrically connecting the second-1 metal plate pattern and the second-2 metal plate pattern to each other.

[0020] In the transformer according to the present invention, the area of ​​the first metal plate pattern (NS1) and the area of ​​the second metal plate pattern (NS2) may be different from each other.

[0021] The transformer according to the present invention can improve the heating temperature by making the magnetic flux distribution uniform, and can reduce the parasitic capacitance by minimizing the overlapping area between coils.

[0022] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0023] Figure 1 is an exemplary diagram showing an example of a typical transformer configuration.

[0024] Figure 2 is a perspective view of a transformer according to the present invention.

[0025] Figure 3 is an exploded perspective view of a transformer according to the present invention.

[0026] FIG. 4 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to the first embodiment of the present invention.

[0027] Fig. 5 is an exemplary diagram showing the cross-section and magnetic flux distribution of a transformer according to the first embodiment.

[0028] FIG. 6 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a second embodiment of the present invention.

[0029] Fig. 7 is an exemplary diagram showing the cross-section and magnetic flux distribution of a transformer according to the prior art.

[0030] FIG. 8 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a third embodiment of the present invention.

[0031] FIG. 9 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a fourth embodiment of the present invention.

[0032] Fig. 10 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a fifth embodiment of the present invention.

[0033] Fig. 11 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a sixth embodiment of the present invention.

[0034] Fig. 12a is an example diagram showing the waveform noise of a transformer according to the prior art, and Fig. 12b is an example diagram showing the waveform noise of a transformer according to the first embodiment.

[0035] With respect to the embodiments of the present invention disclosed in the text, specific structural and functional descriptions are merely illustrative for the purpose of explaining the embodiments of the present invention, and the embodiments of the present invention may be implemented in various forms and should not be construed as being limited to the embodiments described in the text.

[0036] The present invention is susceptible to various modifications and takes various forms. Specific embodiments are illustrated in the drawings and described in detail herein. However, this is not intended to limit the present invention to specific disclosed forms, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0037] While terms like "first" and "second" may be used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component."

[0038] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components in between. Conversely, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between. Other expressions that describe the relationship between components, such as "between" and "immediately between" or "adjacent to" and "directly adjacent to", should be interpreted similarly.

[0039] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprises" or "has" indicate the presence of a disclosed feature, number, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0040] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted to have a meaning consistent with their meaning in the context of the relevant technology, and shall not be construed in an idealized or overly formal sense unless explicitly defined herein.

[0041] Meanwhile, if a particular embodiment can be implemented differently, the functions or operations specified within a particular block may occur in a different order than specified in the flowchart. For example, two consecutive blocks may actually be performed substantially simultaneously, or, depending on the related functions or operations, the blocks may be performed in reverse order.

[0042] Hereinafter, a magnetic element according to an embodiment of the present invention will be described in detail with reference to the attached drawings. For convenience of explanation, a transformer is described as an example of a magnetic coupling device in FIGS. 2 to 10. However, the transformer is only one example of the magnetic element according to the embodiment and is not necessarily limited thereto. For example, the magnetic element according to the embodiment may be a component of an inductor or an EMI filter.

[0043] Figure 2 is a perspective view of a transformer according to the present invention, and Figure 3 is an exploded perspective view of a transformer according to the present invention.

[0044] As illustrated, a transformer according to the present invention comprises a core portion (100) and a coil portion (200). The core portion (100) has the characteristics of a magnetic circuit and can act as a path for magnetic flux. The core portion (100) can include an upper core (110) coupled from the upper side and a lower core (120) coupled from the lower side.

[0045] The two cores (110, 120) may have a shape that is symmetrical vertically, or an asymmetrical shape, and may have a shape in which either the upper core (110) or the lower core (120) is removed. However, in the description below, it is assumed that the shapes are symmetrical vertically for convenience of explanation.

[0046] Each of the upper core (110) and the lower core (120) may include a body portion in the form of a flat plate and a plurality of leg portions (OL1-1, OL1-2, OL2-1, OL2-2, CL1, CL2) protruding from the body portion in a first direction (i.e., uniaxial direction) and extending along a predetermined direction. For example, the plurality of leg portions (OL1-1, OL1-2, CL1) of the upper core (110) may include two outer legs (OL1-1, OL1-2) spaced apart from each other along a second direction (i.e., 2-axial direction) intersecting the first direction on a plane, and one middle leg (CL1) arranged between the two outer legs (OL1-1, OL1-2). Additionally, each of the plurality of leg portions (OL1-1, OL1-2, OL2-1, OL2-2, CL1, CL2) can extend along a third direction (i.e., a triaxial direction) intersecting the first and second directions on the plane.

[0047] When the upper core (110) and the lower core (120) are connected vertically, the outer legs (OL1-1, OL1-2) and the middle legs (CL1) of the upper core (110) each face the corresponding outer legs (OL2-1, OL2-2) or middle legs (CL2) of the lower core (120). The outer leg pair (OL1-1, OL2-1) facing each other may be referred to as a first outer leg, the outer leg pair (OL1-2, OL2-2) facing each other may be referred to as a second outer leg, and the middle leg pair (CL1, CL2) may be referred to as a middle leg.

[0048] A gap of a predetermined distance (e.g., 10 to 200 m, but not necessarily limited thereto) may be formed between at least some of the opposing exo- or intermediate pairs. By adjusting the gap size of each of one intermediate pair and two external pairs, the inductance of the core portion (110) can be controlled, and heat generation can be controlled depending on the number of gaps.

[0049] Additionally, the core portion (100) may include a magnetic material, for example, iron or ferrite, but is not necessarily limited thereto.

[0050] Since the core part (100) surrounds a part of the coil part (200), it can be seen that a part of the coil part (200) is placed within the core part (100).

[0051] The coil portion (200) is composed of a first conductive pattern substrate (210) and a second conductive pattern substrate (220).

[0052] Each of the first conductive pattern substrate (210) and the second conductive pattern substrate (220) has a through hole (TH) through which the mid-foot portion (CL1, CL2) of the core portion (100) passes.

[0053] The first conductive pattern substrate (210) includes an upper first conductive pattern substrate (211) and a lower first conductive pattern substrate (212) disposed thereunder.

[0054] The second conductive pattern substrate (220) includes an upper second conductive pattern substrate (221) insulatively laminated on top of the upper first conductive pattern substrate (211) of the first conductive pattern substrate (210), and a lower second conductive pattern substrate (222) insulatively arranged on bottom of the lower first conductive pattern (212) of the first conductive pattern substrate (210). Of course, each of the first conductive pattern substrate (210) and the second conductive pattern substrate (220) may be applied as a single substrate.

[0055] The first conductive pattern substrate (210) can form a primary coil of the transformer, and the second conductive pattern substrate (220) can form a secondary coil of the transformer. Of course, depending on the implementation, the first conductive pattern substrate (210) can form a secondary coil of the transformer, and the second conductive pattern substrate (220) can form a primary coil of the transformer.

[0056] The second conductive pattern substrate (220) may be formed by including an upper second conductive pattern substrate (221) and a lower second conductive pattern substrate (222).

[0057] In the longitudinal direction of the coil portion (200), a first terminal portion (TP1) may be arranged in parallel and spaced apart from each other along the short-axis direction at one end, and a second terminal portion (TP2) may be arranged in parallel and spaced apart from each other along the short-axis direction at the other end opposite to the one end in the longitudinal direction.

[0058] The terminal portion (TP1, TP2) may include a plurality of terminal pads (TP1_1 … TP1_4, TP2_1 … TP2_8) for electrically connecting the transformer to a circuit portion formed on the device substrate.

[0059] Each terminal pad (TP1_1, …, TP1_4, TP2_1, …, TP2_8) can be arranged on each of a plurality of conductive pattern substrates (211, 212, 221, 222), and the terminal pads of each conductive pattern can be aligned and electrically connected to each other in the vertical direction.

[0060] Fig. 4 is a split plan view schematically showing the arrangement of conductive pattern substrates in a transformer according to a first embodiment of the present invention. As shown, it is an exemplary diagram in which a plurality of conductive pattern substrates (221A, 211A, 212A, 222A) that are stacked to form a coil portion (200) are arranged sequentially from the top to the left to the right. At this time, the arrangement of the first metal plate pattern (NS1) and the second metal plate patterns (NS2-1, NS2-2) in the upper second conductive pattern substrate (221A) and the lower second conductive pattern substrate (222A) is symmetrical to each other. In the transformer according to the present invention, the first metal plate pattern (NS1) and the second metal plate pattern (NS2) may have areas of different sizes.

[0061] On the upper second conductive pattern substrate (221A) of the second conductive pattern substrate (220) disposed at the top, a second-first metal plate pattern (NS2-1) and a second-second metal plate pattern (NS2-2) are disposed spaced apart from each other with the first metal plate pattern (NS1) therebetween. At this time, the second-first metal plate pattern (NS2-1) is disposed to surround the second through hole (TH2). The second-first metal plate pattern (NS2-1) and the second-second metal plate pattern (NS2-2), which are spaced apart from each other, are electrically connected through via holes (VH1, VH2) formed in each pattern. At this time, the electrical connection is made through the first via hole (VH1) and the second via hole (VH2) of the first connection pattern (CP1) formed in the upper first conductive pattern substrate (211A) disposed below the upper second conductive pattern substrate (221A).

[0062] The upper first conductive pattern substrate (211A) includes a first wire pattern (201A) that forms at least one turn in a counterclockwise direction around a first through hole (TH1) formed at the center. The lower first conductive pattern substrate (212A) includes a second wire pattern (202A) that forms at least one turn in a clockwise direction around the first through hole (TH1) formed at the center. The first wire pattern (201A) is electrically connected to the second wire pattern (202A) arranged on the lower first conductive pattern substrate (212A). To this end, a fifth via hole (VH5) is formed at one end of the first wire pattern (201A) and one end of the second wire pattern (202A), respectively.

[0063] The first to fifth via holes formed in the conductive pattern and wire pattern of each conductive pattern substrate are vertically overlapped and electrically connected to each other, and are indicated by the same symbol.

[0064] Meanwhile, a second connection pattern (CP2) is formed on the lower first conductive pattern substrate (212A) for the same purpose as that of forming the first connection pattern (CP1) on the upper first conductive pattern substrate (211A). A third via hole (VH3) and a fourth via hole (VH4) are formed on the second connection pattern (CP2). The 4-1 metal plate pattern (NS4-1) and the 4-2 metal plate pattern (NS4-2), which are formed to be spaced apart from each other on the lower second conductive pattern substrate (222A), are electrically connected through the third via hole (VH3) and the fourth via hole (VH4). At this time, the electrical connection is made through the third via hole (VH3) and the fourth via hole (VH4) formed on the lower first conductive pattern substrate (212A).

[0065] Fig. 5 is an exemplary diagram showing a cross-section and a distribution of magnetic flux of a transformer according to the first embodiment. As illustrated in Fig. 5, in the transformer according to the present invention, the first metal plate pattern (NS1) and the second metal plate pattern (NS2) arranged on the upper second conductive pattern substrate may have a structure that is symmetrical with respect to the first metal pattern (NS1) and the second metal plate pattern (NS2) arranged on the lower second conductive pattern substrate with the primary coil as the center.

[0066] Fig. 6 is a split plan view schematically showing the arrangement of conductive pattern substrates in a transformer according to a second embodiment of the present invention, and Fig. 7 is an exemplary diagram showing a cross-section and magnetic flux distribution of a transformer according to the second embodiment. Fig. 6 is an exemplary diagram in which a plurality of conductive pattern substrates (221B, 211B, 212B, 222B) that are stacked to form a coil portion are arranged sequentially from the top to the left to the right, similar to the first embodiment of Fig. 4. At this time, the first metal plate pattern (NS1) and the second metal plate patterns (NS2-1, NS2-2) on the upper second conductive pattern substrate (221B) and the lower second conductive pattern substrate (222B) are arranged at the same position so as to be vertically overlapped.

[0067] A first metal plate pattern (NS1) and a second metal plate pattern (NS2) are formed on the upper second conductive pattern substrate (221B) of the second conductive pattern substrate (220) disposed at the top. The second metal plate pattern (NS2) is disposed such that a second-first metal plate pattern (NS2-1) and a second-second metal plate pattern (NS2-2) are spaced apart from each other with the first metal plate pattern (NS1) interposed therebetween. At this time, the second-first metal plate pattern (NS2-1), which is one of the second metal plate patterns, is disposed to surround the second through hole (TH2). The second metal plate patterns (NS2-1, NS2-2) spaced apart from each other are electrically connected through a first via hole (VH1) and a second via hole (VH2) formed in each pattern. At this time, the electrical connection is made through the first via hole (VH1) and the second via hole (VH2) of the first connection substrate (CP1) formed on the upper first conductive pattern substrate (211B) placed under the upper second conductive pattern substrate (221B).

[0068] The upper first conductive pattern substrate (211B) includes a first wire pattern (201B) that forms at least one turn in a counterclockwise direction around a first through hole (TH1) formed at the center. The lower first conductive pattern substrate (212B) includes a second wire pattern (202B) that forms at least one turn in a clockwise direction around the first through hole (TH1) formed at the center. The first wire pattern (201B) is electrically connected to the second wire pattern (202B) arranged on the lower first conductive pattern substrate (212B). To this end, a fifth via hole (VH5) is formed at one end of the first wire pattern (201B) and one end of the second wire pattern (202B), respectively.

[0069] Meanwhile, unlike the first embodiment, a second connection pattern (CP2) having the same shape as the first connection pattern (CP1) of the upper first conductive pattern substrate (211B) is formed at the same position in the vertical direction on the lower first conductive pattern substrate (212B) according to the second embodiment. A third via hole (VH3) and a fourth via hole (VH4) are formed on the second connection pattern (CP2) for electrical connection with the lower second conductive pattern substrate (222B).

[0070] The lower second conductive pattern substrate (222B) includes a fourth metal plate pattern (NS4-1, NS4-2) formed spaced apart from each other, and a third via hole (VH3) and a fourth via hole (VH4) formed at a position vertically overlapping with the third via hole (VH3) and the fourth via hole (VH4).

[0071] The via hole (VH3) of the 4-1 metal plate pattern (NS4-1) of the lower second conductive pattern substrate (222B) is electrically connected to the third via hole (VH3) of the lower first conductive pattern substrate (212B), and the fourth via hole (VH4) of the 4-2 metal plate pattern (NS4-2) of the lower second conductive pattern substrate (222B) is electrically connected to the fourth via hole (VH4) of the lower first conductive pattern substrate (212B).

[0072] In a transformer according to the present invention, the first metal plate pattern (NS1) and the second metal plate pattern (NS2-1, NS2-2) disposed on the upper second conductive pattern substrate (221B) may have a structure in which they are disposed to overlap in the vertical direction with respect to the third metal pattern (NS3) and the fourth metal plate pattern (NS4-1, NS4-2) disposed on the lower second conductive pattern substrate (222B).

[0073] Referring to FIGS. 5 and 7, in a transformer according to the prior art having a structure as illustrated in FIG. 7, the current flowing in the secondary coils (NS1 and NS2) alternates between up and down. Therefore, the magnetic flux is not evenly distributed throughout the core but is unevenly biased in one direction. However, when the secondary coils are arranged on the same plane as the first metal plate pattern (NS1) and the second metal plate pattern (NS2) as in the first and second embodiments of the present invention, the current alternates between up and down symmetrical directions. Therefore, the distribution of the magnetic flux becomes relatively uniform compared to the existing structure, thereby improving the heating temperature.

[0074] FIG. 8 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a third embodiment of the present invention, and FIG. 9 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a fourth embodiment of the present invention.

[0075] What the first and second embodiments have in common is that the second metal plate patterns (NS2-1, NS2-2) that are divided with the first metal plate pattern (NS1) interposed between them in the upper second conductive pattern substrate (221A, 221B) are electrically connected through the first via hole (VH1) and the second via hole (VH2) formed in the first connection pattern (CP1) formed in the upper first conductive pattern substrate (211A, 211B). In addition, the fourth metal plate patterns (NS4-1, NS4-2) that are divided with the third metal plate pattern (NS3) interposed between them in the lower second conductive pattern substrate (222A, 222B) are electrically connected through the third via hole (VH3) and the fourth via hole (VH4) formed in the second connection pattern (CP2) formed in the lower first conductive pattern substrate (212A, 212B).

[0076] In the third and fourth embodiments of FIGS. 8 and 9, the second metal plate patterns (NS2-1, NS2-2) and the fourth metal plate patterns (NS4-1, NS4-2) that are divided from each other are electrically connected by conductive lines, for example, bus bars.

[0077] Looking at the configuration of the third embodiment illustrated in FIG. 8, a first metal plate pattern (NS1) and second metal plate patterns (NS2-1, NS2-2) are spaced apart from each other on the upper second conductive pattern substrate (221C) disposed at the top, with the first metal plate pattern (NS1) interposed therebetween. At this time, the 2-1 metal plate pattern (NS2-1), which is one of the second metal plate patterns, is disposed to surround the second through hole (TH2). At this time, the 2-1 metal plate pattern (NS2-1) is electrically connected to the 2-2 metal plate pattern (NS2-2) that is divided and spaced apart from each other by the upper first conductive line (L11).

[0078] The upper first conductive pattern substrate (211C) includes a first wire pattern (201C) that forms at least one turn in a counterclockwise direction around a first through hole (TH1) formed at the center. The lower first conductive pattern substrate (212C) includes a second wire pattern (202C) that forms at least one turn in a clockwise direction around the first through hole (TH1) formed at the center. The first wire pattern (201C) of the upper first conductive pattern substrate (212C) is electrically connected to the second wire pattern (202C) arranged on the lower first conductive pattern substrate (212C). To this end, a fifth via hole (VH5) is formed at one end of the first wire pattern (201C) and one end of the second wire pattern (202C), respectively.

[0079] On the lower second conductive pattern substrate (222C), metal plate patterns (NS3, NS4-1, NS4-2) are formed that are symmetrical in the second direction with respect to the upper second conductive pattern substrate (221C) with the second through hole (TH2) as the center. At this time, the 4-1 metal pattern (NS4-1) of the lower secondary substrate (222C) is electrically connected to the spaced-apart 4-2 metal plate pattern (NS4-2) by the lower first conductive line (L21).

[0080] Looking at the configuration of the fourth embodiment illustrated in FIG. 9, second metal plate patterns (NS2-1, NS2-2) are spaced apart from each other on the upper second conductive pattern substrate (221D) disposed at the top with the first metal plate pattern (NS1) interposed therebetween. At this time, the 2-1 metal plate pattern (NS2-1), which is one of the second metal plate patterns, is disposed to surround the second through hole (TH2). At this time, the 2-1 metal plate patterns (NS2-1) spaced apart from the 2-2 metal plate pattern (NS2-2) are electrically connected to each other by the upper second conductive line (L21).

[0081] The upper first conductive pattern substrate (211D) includes a first wire pattern (201D) that forms at least one turn in a counterclockwise direction around a first through-hole (TH1) formed at the center. The lower first conductive pattern substrate (212D) includes a second wire pattern (202D) that forms at least one turn in a clockwise direction around the first through-hole (TH1) formed at the center. The first wire pattern (201D) is electrically connected to the second wire pattern (202D) arranged on the lower first conductive pattern substrate (212D). To this end, a fifth via hole (VH5) is formed at one end of the first wire pattern (201D) and one end of the second wire pattern (202D). A metal plate pattern having the same shape as the upper second conductive pattern substrate (221D) is arranged on the lower second conductive pattern substrate (222D). That is, on the lower second conductive pattern substrate (222D), the 4-1 metal plate pattern (NS4-1) and the 4-2 metal plate pattern (NS4-2) are arranged spaced apart from each other with the 3rd metal plate pattern (NS3) therebetween. At this time, the 4-2 metal plate pattern (NS4-2) of the lower second conductive pattern substrate (222D) is electrically connected to the spaced-apart 4-1 metal plate pattern (NS4-1) by the lower second conductive line (L22).

[0082] FIG. 10 is a split plan view schematically showing the arrangement of a conductive pattern substrate in a transformer according to a fifth embodiment of the present invention. Unlike the transformers according to the first to fourth embodiments, the second conductive pattern substrate is formed of one second conductive pattern substrate (220E). The first conductive pattern substrate (210) is formed of an upper first conductive pattern substrate (211E) and a lower first conductive pattern substrate (212E). A first metal plate pattern (NS1) and a second metal plate pattern (NS2) are formed on the second conductive pattern substrate (220E). The second metal plate pattern (NS2) includes a second-first metal pattern (NS2-1) and a second-second metal pattern (NS2-2). The second-first metal pattern (NS2-1) and the second-second metal pattern (NS2-2) are spaced apart from each other with the first metal plate pattern (NS1) therebetween. At this time, the 2-1 metal plate pattern (NS2-1) is arranged to surround the second through hole (TH2). The 2-1 metal plate pattern (NS2-1) and the 2-2 metal plate pattern (NS2-2), which are spaced apart from each other, are electrically connected through the first via hole (VH1) and the second via hole (VH2) formed in each pattern. At this time, the electrical connection is made through the first via hole (VH1) and the second via hole (VH2) of the first connection pattern (CP1) formed in the upper first conductive pattern substrate (211E) arranged under the second conductive pattern substrate (220E).

[0083] The upper first conductive pattern substrate (211E) includes a first wire pattern (201E) that forms at least one turn in a counterclockwise direction around a first through hole (TH1) formed at the center. The lower first conductive pattern substrate (212E) includes a second wire pattern (202E) that forms at least one turn in a clockwise direction around the first through hole (TH1) formed at the center. The first wire pattern (201E) is electrically connected to the second wire pattern (202E) arranged on the lower first conductive pattern substrate (212EA). To this end, a fifth via hole (VH5) is formed at one end of the first wire pattern (201E) and at each end of the second wire pattern (202E).

[0084] Fig. 11 is a split plan view schematically showing the arrangement of conductive pattern substrates in a transformer according to a sixth embodiment of the present invention. This is an embodiment in which the first conductive pattern substrate and the second conductive pattern substrate are each formed as one substrate. At this time, the second conductive pattern substrate (220F) includes a first metal plate pattern (NS1) and a second metal plate pattern (NS2). The second metal plate pattern (NS2) includes a 2-1 metal plate pattern (NS2-1) and a 2-2 metal plate pattern (NS2-2). The 2-1 metal plate pattern (NS2-1) and the 2-2 metal plate pattern (NS2-2) are spaced apart from each other with the first metal plate pattern (NS1) interposed therebetween. The 2-1 metal plate pattern (NS2-1) and the 2-2 metal plate pattern (NS2-2), which are spaced apart from each other, are electrically connected through a first via hole (VH1) and a second via hole (VH2) formed in each pattern. At this time, the electrical connection is made through the first via hole (VH1) and the second via hole (VH2) of the first connection pattern (CP1) formed on the first conductive pattern substrate (210F). The first conductive pattern substrate (210F) includes a first wire pattern (201F) that forms at least one turn in a counterclockwise direction around the first through hole (TH1) formed at the center.

[0085] When the capacitance between the primary coil and the secondary coil in a transformer according to the prior art having a vertically overlapping secondary coil pattern substrate of a printed circuit board type is 230 pF, the capacitance between the secondary coils is measured to be 90.44 pF and the heating temperature is 81.2°C. Fig. 12a is an example diagram showing a noise waveform in a transformer according to the prior art.

[0086] Meanwhile, in the case where the secondary coil is disposed on the same plane as the first metal plate pattern (NS1) and the second metal plate pattern (NS2) as in the first embodiment of the present invention, but the second metal plate pattern (NS2) is divided into a second-first metal plate pattern (NS2-1) and a second-second metal plate pattern (NS2-2), and the second metal plate pattern (NS1) is disposed spaced apart from each other, when the capacitance between the first coil and the second coil is 120 pF, the capacitance between the secondary coils is measured to be 79.9 pF and the heating temperature is 73.7°C. That is, since the current is transmitted in the upper and lower symmetrical directions, the distribution of the magnetic flux becomes uniform compared to the existing structure, and thus the parasitic capacitance and the heating temperature are relatively lowered compared to the prior art. Therefore, it can be seen that the noise of the waveform is improved, as in the noise waveform example of FIG. 12b.

[0087] As described above, by dividing the secondary coil pattern and placing it on one substrate and connecting the secondary coil pattern using a center tab, the inter-winding capacitance between the primary and secondary coils and the parasitic capacitance between the secondary coils can be reduced, and the heating temperature can be lowered while designing the stacking height of the secondary coil to be low.

[0088] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0089] The transformer according to the present invention can be applied to various electronic devices.

Claims

1. Core portion including an upper core and a lower core; A coil portion at least partially disposed inside the core portion; The above coil part, A first conductive pattern substrate including a first through hole formed so that the middle part of the core portion penetrates therethrough and a first conductive pattern having at least one turn formed to surround the first through hole; and A second conductive pattern substrate including a second through hole formed so that the middle of the core portion penetrates through it and a plurality of second conductive patterns having at least one turn formed to surround the second through hole, The second conductive pattern substrate is a transformer arranged at at least one position among the upper and lower portions of the first conductive pattern substrate.

2. In the first paragraph, the plurality of second challenging patterns are: First metal plate pattern (NS1); A transformer including a plurality of second metal plate patterns (NS2) spaced apart from each other with the first metal plate pattern (NS1) interposed therebetween.

3. In the second paragraph, a transformer in which the area of ​​the first metal plate pattern (NS1) and the area of ​​the second metal plate pattern (NS2) are different from each other.

4. In paragraph 2, The above plurality of second metal plate patterns (NS2) are, A second-first metal plate pattern (NS2-1) arranged between the first metal plate pattern (NS1) and the second through hole; and A transformer including a second-second metal plate pattern (NS2-2) spaced apart from the second-first metal plate pattern (NS2-1).

5. In paragraph 4, The above 2-1 metal plate pattern (NS2-1) and the 2-2 metal plate pattern (NS2-2) are a transformer electrically connected to each other.

6. In paragraph 5, A transformer further comprising a conductive line disposed on the second conductive pattern substrate and electrically connecting the second-1 metal plate pattern and the second-2 metal plate pattern to each other.

7. In paragraph 5, A transformer in which the first conductive pattern substrate includes a first connection pattern (CP1) formed around the first conductive pattern, and the first connection pattern (CP1) includes a first via hole and a second via hole.

8. In paragraph 7, Each of the above plurality of second metal plate patterns (NS2) includes a via hole, A transformer in which the via hole of the above 2-1 metal plate pattern (NS2-1) is electrically connected to the above 1st via hole, and the via hole of the above 2-2 metal plate pattern (NS2-2) is electrically connected to the above 2nd via hole.

9. In the 8th paragraph, the first conductive pattern substrate, An upper primary substrate having a first wire pattern formed on one side with a center tab formed thereon; and A transformer comprising a lower primary substrate disposed below the upper primary substrate and having a second wire pattern formed thereon, the second wire pattern having a shape symmetrical to the first wire pattern.

10. A transformer in claim 9, wherein the second conductive pattern substrate includes a plurality of upper secondary substrates arranged on top of the first conductive pattern substrate and a lower secondary substrate arranged on bottom of the first conductive pattern substrate and including a plurality of second conductive patterns.

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