JP2005064321A - Coil component and electronic device equipped with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coil component that can be reduced in size by reducing the mounting area by reducing the number of components, and to provide electronic device equipped with the component. <P>SOLUTION: The coil component is provided with a magnetic core 11 formed by press-molding the powder of a magnetic material after the powder is covered with an insulating coating film and a binder is mixed in the powder, a plurality of coils 12 embedded in the core 11, and terminals 13 connected to or extended from the coils 12 and protruded from the core 11. The coils 12 are embedded in the core 11 and, at the same time, are made to jointly function as a voltage converting component in a DC-DC circuit by connecting the coils 12 in parallel with each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a coil component used for various electronic devices and the like and an electronic device on which the coil component is mounted.

  Hereinafter, a conventional coil component and an electronic device on which the coil component is mounted will be described with reference to the drawings.

  13 is a cross-sectional view of a conventional coil component, FIG. 14 is a block diagram of an electronic device on which the coil component is mounted, and FIG. 15 is an equivalent circuit diagram of a multi-phase circuit of the coil component.

  As shown in FIG. 13, a conventional coil component includes a magnetic core 1 made of powdered magnetic material, covered with an insulating film, mixed with a binder, and press-molded, and one coil 2 embedded in the magnetic core 1. Further, both ends of the coil 2 are extended, and a terminal portion 3 formed by protruding from the magnetic core 1 is provided.

  For example, as shown in FIG. 14, the coil component is used in a drive power supply circuit of a CPU 4 used in an information terminal device. This drive power supply circuit is composed of a multi-phase circuit 6 having a DC-DC circuit 5 for supplying power for operating the CPU 4. The DC-DC circuit 5 has the above-described coil components for the choke coil 7. Used. Since a large current of about several tens of amperes is required for the consumption current of the CPU 4, a plurality of the above coil components in which the coil 2 is embedded alone in the magnetic core 1 are used, and a large current is generated by connecting the coils 2 in parallel with each other. It has gained.

  At this time, each coil 2 embedded alone in each magnetic core 1 functions as a voltage conversion component in the DC-DC circuit 5 together.

  An equivalent circuit of the multiphase circuit 6 is as shown in FIG.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2002-252120 A

  In the above configuration, in order to drive one CPU 4, a large current is obtained by connecting a plurality of coil components in parallel for the choke coil 7 to the DC-DC circuit 5. Since a plurality of coil parts are used, the mounting area of the total number of coil parts is required as much, and the above configuration has a problem that the mounting area cannot be reduced and the size cannot be reduced.

  An object of the present invention is to solve the above problems, and to provide a coil component capable of reducing the mounting area by reducing the number of components and reducing the size, and an electronic device on which the coil component is mounted.

  In order to solve the above problems, the present invention has the following configuration.

  According to the first aspect of the present invention, a magnetic material is powdered, the surface is covered with an insulating film, a magnetic core is formed by pressing a binder and mixed, a coil embedded in the magnetic core, and a connection or extension to the coil. A multi-phase circuit having a DC-DC circuit, wherein a plurality of the coils are embedded in the magnetic core and connected in parallel to each other, and the coils are jointly connected. In addition to functioning as a voltage conversion component in the DC-DC circuit, the temperature characteristics and circuit efficiency are functioning as voltage conversion components in the DC-DC circuit by the coils embedded in the magnetic core. In this case, the temperature characteristics and circuit efficiency are almost the same.

  With the above configuration, a plurality of coils are embedded in a magnetic core and are connected in parallel to each other. Therefore, in a DC-DC circuit, a single coil is embedded in one magnetic core and a plurality of coil components are used. The function of a plurality of coil components can be obtained with one coil component, the number of coil components used can be reduced, and the mounting area can be reduced.

  The invention according to claim 2 of the present invention is the configuration according to claim 1, in particular, wherein the plurality of coils are arranged at positions where the coupling coefficient of the adjacent coils is 0.7 or more.

  With the above configuration, each coil can easily function as a voltage conversion component in a DC-DC circuit, and the temperature characteristics and circuit efficiency are also shared by each coil embedded in a plurality of magnetic cores. The temperature characteristics and circuit efficiency when functioning as a voltage conversion component in a DC-DC circuit can be made substantially equal.

  According to a third aspect of the present invention, in the first aspect of the present invention, in particular, the magnetic core is formed by combining a single magnetic core in which a plurality of the coils are individually embedded.

  With the above configuration, a plurality of coils can be embedded in a magnetic core easily and accurately, and can be connected in parallel with each other.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, in particular, the plurality of coils are arranged with the winding axis direction in the same direction.

  With the above configuration, the direction of the magnetic flux generated from each coil can be aligned in the same direction, and the generated magnetic flux can be easily balanced. The amount of magnetic flux interacting with each other coil is also easily reduced, and each coil can be made to function jointly as a voltage conversion component in the DC-DC circuit.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, in particular, the plurality of coils are laminated.

  With the above configuration, each coil is laminated while reducing the amount of magnetic flux interacting with each other coil, so that the mounting area is also reduced, and each coil is jointly used as a voltage conversion component in each DC-DC circuit. Can function.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, in particular, the plurality of coils are configured such that the winding axes are positioned in the same straight line.

  With the above configuration, each coil is laminated so that the winding axis is positioned in the same straight line while reducing the amount of magnetic flux interacting with each other coil, so that the mounting area is further reduced and each coil is shared. Thus, it can function as a voltage conversion component in each DC-DC circuit.

  According to a seventh aspect of the present invention, in the sixth aspect of the present invention, in particular, between the coils, the magnetic permeability is smaller than the magnetic permeability of the magnetic core, and a through hole is formed on the opposing surface of the coil. And a spacer having a gap portion interposed between the end portions of the magnetic core without being in contact with both ends of the magnetic core.

  With the above configuration, a plurality of coils can be embedded in a magnetic core easily and accurately, and can be connected in parallel with each other. In particular, the magnetic flux generated from the coils is likely to interact with each coil.

  According to an eighth aspect of the present invention, in the sixth aspect of the present invention, between the coils, the magnetic permeability is larger than the magnetic permeability of the magnetic core, and a spacer is interposed on the opposing surface of the coil. It is a configuration.

  With the above configuration, a plurality of coils can be embedded in a magnetic core easily and accurately, and can be connected in parallel with each other. In particular, the magnetic flux generated from the coils is likely to interact with each coil.

  According to a ninth aspect of the present invention, in the fourth aspect of the present invention, in particular, the terminal portions of the coils are connected or extended in opposite directions so as to protrude from the magnetic cores, and between the adjacent coils. A terminal part is the structure arrange | positioned so that it may become zigzag form.

  With the above configuration, it is possible to improve the processing and mounting of the terminal portion with less interference between the upper and lower coils adjacent to each other.

  According to a tenth aspect of the present invention, in the invention according to the fourth aspect, particularly, the adjacent coils have the same polarity.

  With the above configuration, since the magnetic fluxes generated from the coils work to strengthen each other, it is easy to increase the amount of magnetic flux that interacts with each other, and each coil is jointly used for voltage conversion in the DC-DC circuit. It can function as a component.

  According to an eleventh aspect of the present invention, the coil component according to the first aspect is mounted on an electronic device.

  With the above configuration, the mounting area of the coil component can be reduced, and at least the electronic device can be reduced in size by the reduced mounting area.

  As described above, according to the present invention, a plurality of coils are embedded in a magnetic core, and are connected in parallel with each other to function together. Therefore, in a DC-DC circuit, one coil is embedded in one magnetic core and a plurality of coils are embedded. Compared to the conventional case where coil parts are used, the function of a plurality of coil parts can be obtained with one coil part, and the number of coil parts used can be reduced and the mounting area can be reduced. Further, the electronic device can be miniaturized at least by the reduced mounting area of the coil component.

  DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

  1 is a cross-sectional view of a coil component according to an embodiment of the present invention, FIG. 2 is a perspective view of the coil component, FIG. 3 is a perspective view of a coil in which a terminal portion used for the coil component is extended, and FIG. FIG. 5 is an equivalent circuit diagram of the multi-phase circuit of the coil component, FIG. 6 is a characteristic waveform diagram showing temperature characteristics in the multi-phase circuit, and FIG. 7 is the multi-phase circuit. FIG. 8 is an explanatory diagram showing a state of magnetic flux flow in the coil component.

  1 to 3, a coil component according to an embodiment of the present invention includes a magnetic core 11 made of powdered magnetic material, covered with an insulating film, mixed with a binder, and press-molded, and embedded in the magnetic core 11. And a terminal portion 13 connected to or extending from the coil 12 and projecting from the magnetic core 11.

  For example, as shown in FIG. 4, the coil component is mounted on an electronic device using a drive power circuit of a CPU 14 used in an information terminal device. This drive power supply circuit is composed of a multi-phase circuit 16 having a DC-DC circuit 15 for supplying power for operating the CPU 14, and the above-described coil component is used for the choke coil 17 in the DC-DC circuit 15. ing. Since a large current of about several tens of amperes is required for the consumption current of the CPU 14, a large current is obtained by adjusting, for example, by shifting the phase of input signals input to the plurality of DC-DC circuits 15.

  In the multi-phase circuit 16 having the DC-DC circuit 15, the coil components include a plurality of coils 12 embedded in the magnetic core 11 and connected in parallel to each other, and the coils 12 jointly operate on the voltage in the DC-DC circuit 15. It functions as a conversion part. An equivalent circuit of the multiphase circuit 16 is as shown in FIG.

  At this time, the temperature characteristics and circuit efficiency are substantially the same as the temperature characteristics and circuit efficiency when each coil 12 embedded in a plurality of magnetic cores 11 functions as a voltage conversion component in the DC-DC circuit 15.

  The outer dimensions of this coil component are 10 mm square or less in length and width and 7.5 mm or less in height, and when functioning as a voltage conversion component in the DC-DC circuit 15, its temperature characteristics and circuit efficiency are: These are as shown in FIGS. 6 and 7, respectively.

  The characteristic waveform 21 showing the temperature characteristic in FIG. 6 rises as the output current increases.

  The characteristic waveform 22 showing the efficiency in FIG. 7 shows the maximum in a specific current region as the output current increases, and then decreases as the output increases. When the input voltage is 15 V, the upper characteristic is shown. When the input voltage is 19V, the lower characteristic waveform is obtained. This efficiency is calculated by the equation of (output voltage) × (output current) / (input voltage) × (input current).

  In addition, the plurality of coils 12 embedded in the magnetic core 11 are arranged at positions where the coupling coefficient of the adjacent coils 12 is 0.7 or more. In general, the coupling coefficient is obtained by the following equation.

  In particular, in the above coupling coefficient range, the coupling between the coils 12 is very large. In order to easily obtain the coupling coefficient range, a plurality of coils 12 embedded in the magnetic core 11 are used. Is a magnetic permeability smaller than the magnetic permeability of the magnetic core 11, has a through hole in the opposing surface of the coil 12, does not contact both ends of the magnetic core 11, and forms a gap portion 24 between the end portions of the magnetic core 11. A spacer 18 is interposed.

  As shown in FIGS. 2 and 3, the plurality of coils 12 are stacked so that the winding axis direction (A) is in the same direction such as the vertical direction, and the winding axis 20 is positioned in the same straight line. Yes. At this time, the terminal portions 13 of the coils 12 are connected or extended in opposite directions so as to protrude from the magnetic core 11 and arranged so as to be staggered from the terminal portions 13 of the adjacent upper and lower coils 12. In order not to overlap each other.

  Further, the upper and lower adjacent coils 12 have the same polarity.

  The flow of the magnetic flux 19 of the coil component mounted on such an electronic device is as shown in FIG. That is, the magnetic flux 19 generated from the plurality of coils 12 circulates around the spacer 18 so as to strengthen each other, and the magnetic flux 19 generated by each coil 12 easily interacts with the adjacent upper and lower coils 12. The coupling coefficient between them increases.

  With the above configuration, a plurality of coils 12 are embedded in the magnetic core 11 and are connected in parallel to each other. Therefore, in the DC-DC circuit 15, one coil 12 is embedded in one magnetic core 11 and a plurality of coil components are used. Compared to the conventional case, the function of a plurality of coil parts can be obtained with one coil part, the number of coil parts used can be reduced, and the mounting area can be reduced.

  In particular, since each coil 12 is disposed at a position where the coupling coefficient of adjacent coils 12 is 0.7 or more, each coil 12 can easily function as a voltage conversion component in the DC-DC circuit 15. Can be made. The temperature characteristics and circuit efficiency can also be made substantially equal to the temperature characteristics and circuit efficiency when each coil 12 embedded in a plurality of magnetic cores 11 functions as a voltage conversion component in the DC-DC circuit 15.

  At this time, between the plurality of coils 12 embedded in the magnetic core 11, the magnetic permeability is smaller than the magnetic permeability of the magnetic core 11, and the through-holes are formed on the opposing surface of the coil 12, and the magnetic core 11 is not brought into contact with both ends. Since the spacer 18 having the gap portion 24 is interposed between the end portions of the magnetic core 11, the magnetic flux 19 generated from each coil 12 circulates around the spacer 18 and passes between the adjacent upper and lower coils 12. It becomes easy to interact and the coupling coefficient between the coils 12 becomes large. Therefore, the above effects can be obtained easily and accurately.

  Further, since the plurality of coils 12 are arranged with the winding axis direction (A) in the same direction such as the vertical direction, the direction of the magnetic flux 19 generated from each coil 12 can be aligned in the same direction. If the spacer 18 is interposed between the coils 12, the amount of the magnetic flux 19 that interacts with each coil 12 can be increased equally and easily. The DC-DC circuit 15 can be easily combined with each coil 12. Can function as a voltage conversion component.

  In particular, if a plurality of coils 12 are stacked and the winding shaft 20 is positioned on the same straight line, the mounting area can be reduced, and if the coils 12 have the same polarity, the magnetic flux generated from each coil 12 can be reduced. Since 19 works to strengthen each other, the above effect can be further obtained while reducing the mounting area.

  Further, the terminal portion 13 of the coil 12 is connected or extended in the opposite direction so as to protrude from the magnetic core 11 and is arranged so as to be staggered from the terminal portion 13 of the adjacent coil 12. Between the upper and lower coils 12 adjacent to the portion 13, the processing and mounting properties of the terminal portion 13 can be improved with little interference with each other. Such a configuration includes, for example, those shown in FIG. 9 and FIG. 10. In short, it is only necessary that the terminal portions 13 do not overlap each other between adjacent upper and lower coils 12.

  If such a coil component is used, the mounting area of the coil component can be reduced, and the electronic device can be reduced in size by the reduced mounting area.

  As described above, according to the embodiment of the present invention, a plurality of the coils 12 are embedded in the magnetic core 11 and are connected in parallel to each other so as to function together. Therefore, in the DC-DC circuit 15, one magnetic core 11 is provided. Compared to the conventional case in which one coil 12 is embedded and a plurality of coil parts are used, the function of a plurality of coil parts can be obtained with one coil part, the number of coil parts used is reduced, and the mounting area is reduced. Can be reduced.

  Further, the electronic device can be miniaturized at least by the reduced mounting area of the coil component.

  The spacer 18 in the present embodiment has a magnetic permeability smaller than the magnetic permeability of the magnetic core 11, has a through-hole on the opposing surface of the coil 12, does not contact with both ends of the magnetic core 11, and ends of the magnetic core 11. The gap portion 24 is provided between the magnetic core 11 and the magnetic core 11, but the magnetic permeability of the magnetic core 11 may be larger than that of the magnetic core 11, as shown in FIG.

  Further, as shown in FIG. 12, the magnetic core 11 may be formed by combining a single magnetic core 11 in which a plurality of coils 12 are individually embedded. In this case, similarly to the above, a spacer 18 having a magnetic permeability smaller than that of the single magnetic core 11 is interposed between the single magnetic cores 11 or a spacer 18 having a magnetic permeability larger than that of the single magnetic core 11. May be interposed.

  Although the material of the spacer 18 shown above is not mentioned, any material may be used as long as it does not deviate from its purpose, such as various adhesive materials, resin materials, and conductive materials.

  The present invention has an effect that the mounting area can be reduced, and can be applied to a coil component used in various electronic devices and the like and an electronic device on which the coil component is mounted.

Sectional drawing of the coil components of one embodiment of this invention Perspective perspective view of the coil component The perspective view of the coil extended in the terminal part used for the coil component Block diagram of electronic equipment equipped with the coil components Equivalent circuit diagram of multi-phase circuit of the same coil component Characteristic waveform diagram showing temperature characteristics in the multi-phase circuit Characteristic waveform diagram showing circuit efficiency in the same multi-phase circuit Explanatory drawing which shows the state of the flow of magnetic flux in the coil component The perspective view of the coil component of other embodiment which improved the terminal part of this invention The perspective view of the terminal part of the coil components of other embodiment Sectional drawing of the coil component of other embodiment which improved the spacer of this invention Sectional drawing of the coil component of other embodiment which improved the magnetic core of this invention Sectional view of conventional coil components Block diagram of electronic equipment equipped with the coil components Equivalent circuit diagram of multi-phase circuit of the same coil component

Explanation of symbols

11 Magnetic core 12 Coil 13 Terminal section 14 CPU
DESCRIPTION OF SYMBOLS 15 DC-DC circuit 16 Multiphase circuit 17 Choke coil 18 Spacer 19 Magnetic flux 20 Winding shaft 21 The characteristic waveform which shows a temperature characteristic 22 The characteristic waveform which shows efficiency 24 Gap part

Claims (11)

Magnetic material is powdered, the surface is covered with an insulating film, a binder is mixed and pressure-molded magnetic core, a coil embedded in the magnetic core, and a terminal portion connected to or extending from the coil and protruding from the magnetic core In the multi-phase circuit having a DC-DC circuit, a plurality of the coils are embedded in the magnetic core and connected in parallel to each other, and the coils are jointly used as voltage conversion parts in the DC-DC circuit. In addition to functioning, temperature characteristics and circuit efficiency are substantially the same as temperature characteristics and circuit efficiency when each of the coils embedded alone in a plurality of the magnetic cores collectively function as a voltage conversion component in the DC-DC circuit. Coil parts. The coil component according to claim 1, wherein the plurality of coils are arranged at a position where a coupling coefficient between adjacent coils is 0.7 or more. The coil component according to claim 1, wherein the magnetic core is formed by combining a single magnetic core in which a plurality of the coils are individually embedded. The coil component according to claim 1, wherein the plurality of coils are arranged with the winding axis direction in the same direction. The coil component according to claim 4, wherein the plurality of coils are stacked. The coil component according to claim 5, wherein the plurality of coils are arranged such that winding axes are positioned in the same straight line. Between the coils, the magnetic permeability is smaller than the magnetic permeability of the magnetic core, and the through-holes are formed on the opposing surface of the coil, and are not brought into contact with both ends of the magnetic core, and between the ends of the magnetic core. The coil component according to claim 6, wherein a spacer having a gap portion is interposed. The coil component according to claim 6, wherein a space between the coils is greater than a permeability of the magnetic core, and a spacer is interposed between opposing surfaces of the coils. The coil component according to claim 4, wherein the terminal portions of the coil are connected or extended in opposite directions so as to protrude from the magnetic core, and are arranged so as to be staggered from the terminal portions of the adjacent coils. The coil component according to claim 4, wherein the adjacent coils have the same polarity. An electronic device on which the coil component according to claim 1 is mounted.

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