JP2015126476A - Lc filter and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply obtain an LC filter whose capacitance value is easily adjusted, and which has the large capacitance value and a large inductance value.SOLUTION: An LC filter 1 is constituted by comprising: a lower side base 2 and an upper side base 3 consisting of a non-magnetic material or a magnetic material; and a sheet 4 having insulation. The sheet 4 is bent in a period when four continuous surfaces on which valley surfaces V and mountain surfaces M alternately appear via a side face S is considered as one period. The lower side base 2 and the upper side base 3 have irregular shapes of engaging into rectangular curves of the sheet 4 from lower parts and upper parts, respectively. The sheet 4 is bent by sandwiching the sheet 4 between the lower side base 2 and the upper side base 3 to be pressed, a conductor path 5 provided by meandering on one surface of the sheet 4 shows a coil shape, a plurality of capacitor electrodes 6 provided on the other surface of the sheet 4 face each other, and the LC filter 1 is manufactured.

Description

  The present invention relates to an LC filter configured by providing a coil and a capacitor on a sheet, and a method for manufacturing the LC filter.

  Conventionally, as this type of LC filter, there is an LC noise filter disclosed in Patent Document 1, for example. As shown in FIGS. 2 and 3 of the same document, this LC noise filter is configured by providing a first conductor on the front surface side of the first insulating sheet and a second conductor on the back surface side. Yes. The first insulating sheet is formed by continuously arranging a plurality of folded portions that are folded and stacked via the folded portions.

  The first conductors are provided with ring-shaped inductor conductors that are partially cut out alternately and continuously on the front surface side of each of the folded portions that are continuously arranged. A coil having a predetermined number of turns is formed when the insulating sheets are alternately folded and stacked in the opposite direction. Input / output pins are attached to both ends of the first conductor as external connection conductors, that is, input / output terminals. The second conductor is composed of a capacitor conductor continuously provided on the back side of each folded portion of the first insulating sheet so as to face the inductor conductor. Capacitance is formed between them. A grounding pin is attached to one end of the second conductor as an external connection conductor, that is, a grounding terminal.

  A second insulating sheet having the same configuration as that of the first insulating sheet is prepared, and both the insulating sheets are laminated so that the second conductor is sandwiched between them, and bonded together, so that FIG. LC noise filter shown in FIG.

  9 and 10 of the same document describe a thin and flat SMD (surface mount device) type LC noise filter. As shown in FIG. 9 of the same document, this SMD type LC noise filter is provided with extended regions on both sides in the width direction of the insulating sheet. The input / output terminals at both ends of the first conductor are covered and formed on the extended region. Also, the grounding terminal at one end of the second conductor is also formed with a wide coating on the extended region. The extended region is cut and removed from the insulating sheet except for the region where the input / output terminal and the grounding terminal are covered. The insulating sheet formed in this way is folded as shown in FIG. 10 (A) of the same document to form a laminate. Furthermore, as shown in FIGS. 10 (B) and 10 (C) of the same document, the wide input / output terminal and the ground terminal projecting outward from the laminated body are sequentially folded, respectively. The SMD type LC noise filter shown in FIG.

JP-A-3-259608

  However, the conventional LC noise filter disclosed in Patent Document 1 is constituted by the first conductor on the surface side of the first insulating sheet, as in the equivalent circuit shown in FIG. Since the capacitor is formed between the coil and the coil constituted by the second conductor on the back surface side, a large capacitor capacity cannot be obtained, and adjustment of the capacitance value is difficult. Further, since only a thin insulating sheet exists between the capacitor electrodes, it is difficult to ensure a withstand voltage between the capacitor electrodes. Moreover, since the distance between each conductor which comprises the coil formed in each folding part is only the distance for the thickness of a thin insulating sheet, a big inductance value cannot be obtained.

  In addition, since the first insulating sheet and the second insulating sheet are laminated to form a laminate, a manufacturing process for laminating the sheets is necessary, which causes an increase in the product cost of the LC filter.

  In addition, since the external connection conductor is constituted by a pin and is connected to the first conductor and the second conductor to form the input / output terminal and the ground terminal, connection reliability is reduced at the connection portion between the pin and each conductor. .

  Further, in the conventional SMD type LC noise filter, it takes time to sequentially fold the wide input / output terminal and the ground terminal that protrude outward from the laminate. For this reason, the product cost of the LC filter also increases due to this man-hour.

The present invention has been made to solve such problems,
A sheet having electrical insulation;
A conductor path provided in a meandering manner on one side of the sheet and exhibiting a winding structure by repeatedly bending the sheet;
The LC filter was configured to include a plurality of capacitor electrodes provided on the other surface or one surface of the sheet and facing each other by repeatedly bending the sheet.

  According to this configuration, when one sheet is repeatedly bent, a conductor path formed on one surface of one sheet exhibits a winding structure to form a coil, and the other surface or one surface The capacitor electrodes formed on each other face each other to constitute a capacitor. Here, the distance between the capacitor electrodes facing each other can be easily adjusted by the bent shape of the sheet, and the area of the capacitor electrode can be easily adjusted by the pattern shape. Can be easily secured, and the capacitance value of the capacitor can be easily adjusted. Further, since the distance between the conductor paths constituting the coil, that is, the distance between the windings, can be ensured by a distance corresponding to the bending interval of the sheet, a large inductance value can be obtained. For this reason, unlike a conventional LC filter, unlike a configuration in which a pair of coils is formed on one and other surfaces of a sheet and a capacitor generated between the pair of coils is a capacitor, the capacitance value can be easily adjusted. Moreover, an LC filter having a large capacitance value and inductance value can be easily obtained.

  Further, the present invention is characterized in that the conductor path and the capacitor electrode are formed in a region where the sheets do not overlap.

  According to this configuration, since the conductor path constituting the coil and the capacitor electrode constituting the capacitor are formed in a region where the sheet does not overlap, the capacitor electrode exists in the inner diameter portion of the coil formed by bending the sheet. The capacitor electrode does not block the magnetic flux passing through the inner diameter portion of the coil. For this reason, even if a coil and a capacitor are formed on one sheet, the coil and the capacitor can coexist on one sheet without hindering the functions of the coil and the capacitor.

The present invention also provides:
The sheet is bent at a period of four consecutive surfaces, each having a valley surface and a mountain surface alternately appearing through the side surfaces.
The conductor path meanders on one side of the sheet, with the portion formed on the four continuous surfaces as one cycle,
The capacitor electrode is provided on each side surface on the other surface or one surface of the sheet.

  According to this configuration, the conductor path has a winding structure by meandering while alternately repeating the descending of the bent sheet to the trough and the rising to the crest via the side surface. The capacitor electrode constitutes a counter electrode of the capacitor by facing each side. Accordingly, a single sheet is simply bent at a cycle of four consecutive surfaces as one cycle, whereby a conductor path formed on one surface of the sheet is wound to form a coil, and the other surface or The capacitor electrodes formed on one surface face each other to form a capacitor, and an LC filter is formed.

The present invention also provides:
The sheet is bent with a period of two consecutive surfaces, where an uphill slope and a downhill slope appear alternately, and one cycle,
The conductor path meanders on one side of the sheet, with a portion formed on two continuous surfaces as one cycle,
The capacitor electrode is provided on every other surface of the continuous surface on the other surface or one surface of the sheet.

  According to this configuration, the conductor path has a winding structure by meandering while alternately repeating the rising of the folded sheet to the upslope and the downslope of the downslope. The capacitor electrodes are opposed to each other via an ascending slope or a descending slope, thereby constituting a counter electrode of the capacitor. Accordingly, a single sheet is simply bent at a cycle with two continuous surfaces as one cycle, so that a conductor path formed on one surface of the sheet is wound to form a coil, and the other surface or The capacitor electrodes formed on one surface face each other to form a capacitor, and an LC filter is formed.

  In addition, since the sheet is bent at a cycle with two consecutive surfaces as one cycle and the conductor path meanders at one cycle, the sheet is bent at a cycle with one cycle as one cycle. Compared with the configuration in which the cycle meanders, bending per winding can be performed with a small number of times. For this reason, in the LC filter having the same outer dimensions, a larger number of turns can be earned, so that an LC filter having a large inductance can be provided. Further, in the LC filter having the same number of winding coils, the number of times of folding the sheet can be reduced, so that the reliability of the sheet can be expected to be improved.

  Further, by increasing the width of the conductor path, the height of the conductor path formed on the slope in the radial direction of the coil increases. For this reason, the inner diameter of the wound structure coil is reduced, the cross-sectional area of the inner diameter portion of the coil is reduced, and the magnetic flux does not easily pass through the inner diameter portion of the coil. However, since the DC resistance value of the coil is low, an LC filter having a coil that can flow a large current can be configured. On the other hand, by reducing the width of the conductor path, the height of the conductor path formed on the slope in the radial direction of the coil is reduced. For this reason, since the size of the inner diameter and inner diameter cross-sectional area of the wound structure coil can be secured and the magnetic flux easily passes through the inner diameter of the coil, an LC filter having a coil having a high Q value can be configured. it can. Further, by increasing the meandering amplitude of the conductor path, the cross-sectional area of the inner diameter portion of the wound structure coil can be increased. For this reason, since it becomes easier for the magnetic flux to pass through the inner diameter part of the coil, an LC filter having a coil having a higher Q value can be configured.

  Further, the present invention is characterized in that the conductor path is formed so as to intersect with the folding line of the sheet.

  According to this configuration, the portion where the conductor path is bent by folding the sheet is only the portion where the conductor path intersects the folding line of the sheet. For this reason, since the part by which a conductor track is bent decreases, the improvement of the reliability of a conductor track can be expected. In addition, since most of the conductor track is located on the surface portion, the conductor track of any width can be formed without being affected by the folding of the sheet as compared with the case where the conductor track is formed along the folded portion of the sheet. It becomes easy. For this reason, compared with the case where the conductor path is formed along the folding line of the sheet, the width of the conductor path can be increased, and the DC resistance value of the coil can be easily reduced.

  In addition, the present invention is characterized by including a base material surrounding the periphery of the sheet.

  According to this configuration, the bent shape of the sheet is maintained by the base material surrounding the periphery of the sheet, and the strength is ensured, so that the product handleability of the LC filter is improved. In addition, by forming the base material with a material having a high insulation resistance, it is possible to easily ensure the withstand voltage between the capacitor electrodes, and an LC filter with high reliability can be obtained.

  The present invention also includes a lower base material having a concave and convex shape that fits from below into a sheet curvature, and an upper base material having a concave and convex shape that fits from above into a sheet curvature. It is characterized by that.

  According to this configuration, the bent shape of the sheet is maintained by sandwiching the sheet by the lower base material and the upper base material each having a concavo-convex shape that fits from below and above to the bending of the sheet, Since the strength is ensured, the product handleability of the LC filter is improved. Also with this configuration, by forming the base material with a material having a high insulation resistance, it is possible to easily ensure the withstand voltage between the capacitor electrodes, and an LC filter having high reliability can be obtained.

  Further, the present invention is characterized in that the substrate is made of a nonmagnetic material or a magnetic material.

  According to this configuration, when the base material is made of a non-magnetic material, the magnetic permeability of the base material becomes small, and the inductance value can be kept low, so that an LC filter for high frequency applications is provided. Further, since the magnetic permeability of the base material is increased when the base material is made of a magnetic material, an LC filter having an inductance value of a desired size can be obtained by selecting the type of the magnetic material to be used.

The present invention also provides:
Electrode pads are provided at both ends of the conductor path and at both ends of the plurality of capacitor electrodes, and an electrode pad provided at one end of the conductor path and an electrode pad provided at one end of the plurality of capacitor electrodes. An electrode pad provided at the other end of the conductor path and an electrode pad provided at the other end of the plurality of capacitor electrodes are provided on one side surface of the sheet.
The sheet is bent by exposing a commonly connected electrode pad and each electrode pad provided on one side of the sheet to the surface of the substrate.

  According to this configuration, the electrode pads connected in common and the electrode pads provided on one side surface of the sheet are exposed on the surface of the base material, thereby configuring the external electrodes. For this reason, an LC electrode can be provided with an external electrode, without having any connection part of an electrode pad and a pin. In addition, unlike the conventional LC filter, it is not necessary to sequentially fold the wide terminals protruding outward from the laminated body, and by simply bending the sheet by exposing each electrode pad to the surface of the substrate, the LC The filter can be provided with external electrodes. Therefore, the LC filter provided with the external electrode can be provided with high connection reliability and at low cost.

  The plurality of capacitor electrodes constitute a plurality of capacitors connected in series between electrode pads provided at both ends thereof. For this reason, the capacitance of the LC filter can also be adjusted by selecting the number of capacitors connected in series, and the value of the capacitance is adjusted to be small as the number of capacitors connected in series is increased.

The present invention also provides:
Electrode pads are provided at both ends of the conductor path, and electrode pads for commonly connecting every other capacitor electrode and electrode pads for commonly connecting the remaining capacitor electrodes are provided at both ends of the plurality of capacitor electrodes. The electrode pad provided at one end and the electrode pad provided at one end of the plurality of capacitor electrodes are commonly connected, and the electrode pad provided at the other end of the conductor path and the plurality of capacitor electrodes An electrode pad provided at the other end of the sheet is provided on one side of the sheet,
The sheet is bent by exposing a commonly connected electrode pad and each electrode pad provided on one side of the sheet to the surface of the substrate.

  Also in this configuration, the commonly connected electrode pads and the respective electrode pads provided on one side surface of the sheet are exposed on the surface of the base material to constitute the external electrodes. For this reason, it is possible to provide the LC filter with an external electrode without having any connection part between the electrode pad and the pin or the like, and without requiring man-hours for sequentially folding the wide terminals. The LC filter can be provided with high connection reliability and low cost.

  The plurality of capacitor electrodes constitute a plurality of capacitors connected in parallel between electrode pads provided at both ends thereof. For this reason, the capacitance of the LC filter can also be adjusted by selecting the number of capacitors connected in parallel, and the capacitance value is greatly adjusted when the number of capacitors connected in parallel is increased.

  Further, the present invention is characterized in that the sheet is bent by exposing the commonly connected electrode pads and each electrode pad provided on one side surface of the sheet to one side surface of the substrate.

  According to this configuration, since each electrode pad is exposed on one side surface of the base material, one side surface of the base material is mounted by mounting the base material on the circuit board with the one side surface of the base material facing the substrate surface of the circuit board. The electrode pads exposed to each can be connected to the lands formed on the substrate surface of the circuit board. For this reason, a thin and flat SMD type LC filter can be provided easily and inexpensively without requiring a manufacturing process of laminating a plurality of sheets, which causes an increase in product cost.

  Moreover, this invention comprised the manufacturing method of LC filter which bends a sheet | seat by pressing a sheet | seat between a lower base material and an upper base material.

  According to this configuration, the sheet is bent to form a winding structure, and a plurality of capacitor electrodes are opposed to each other, and the lower base material and the upper base material are fitted to each other to bend the sheet. The step of processing to maintain the strength is performed in one step of pressing with a sheet sandwiched between the lower substrate and the upper substrate. For this reason, a manufacturing process decreases and the product cost of LC filter can further be reduced.

  Further, the present invention is characterized in that pressing is performed with an adhesive applied to both sides of the sheet.

  According to this configuration, the sheet is bent to form a winding structure, and a plurality of capacitor electrodes are opposed to each other, and the lower base material and the upper base material are fitted to each other to bend the sheet. Pressing the sheet between the lower substrate and the upper substrate, and pressing the sheet between the lower substrate and the upper substrate. In one step. For this reason, the manufacturing process is further reduced, and the product cost of the LC filter can be further reduced.

  According to the present invention, as described above, the capacitance value can be easily adjusted, and an LC filter having a large capacitance value and inductance value can be easily obtained.

1 is an external perspective view of an LC filter according to a first embodiment of the present invention. (A) is an external appearance perspective view of the upper base material which comprises LC filter shown in FIG. 1, (b) is an external perspective view of a lower base material. (A) is a top view of the sheet | seat before the sheet | seat which comprises LC filter by 1st Embodiment is bent, (b) is a rear view. It is a schematic diagram for demonstrating the pattern period of the conductor path formed on the sheet | seat shown in FIG. FIG. 4 is a perspective view of a state in which the sheet illustrated in FIG. 3 is bent. It is the external appearance perspective view which looked at the LC filter by a 1st embodiment from the bottom side. It is an equivalent circuit diagram of the LC filter according to the first embodiment. (A) is a perspective view of a state in which the sheet shown in FIG. 3 is bent in another mode, and (b) is an LC filter according to a modification of the first embodiment obtained by including only the lower substrate. (C) is an external perspective view of an LC filter according to another modification of the first embodiment configured by placing the upper base material on the LC filter shown in (b). It is an external appearance perspective view of LC filter by the 2nd Embodiment of this invention. (A) is an external appearance perspective view of the upper base material which comprises LC filter shown in FIG. 9, (b) is an external perspective view of a lower base material. (A) is a top view of the sheet | seat before the sheet | seat which comprises LC filter by 2nd Embodiment is bent, (b) is a rear view. (A) is the perspective view of the state which the sheet | seat shown in FIG. 11 was bent, (b) is the external appearance perspective view which looked at the LC filter by 2nd Embodiment from the bottom face side. 11A is a perspective view of a state in which the sheet shown in FIG. 11 is bent in another mode, and FIG. 11B is an LC filter according to a modification of the second embodiment obtained by including only the lower substrate. (C) is an external perspective view of an LC filter according to another modified example of the second embodiment configured by placing the upper base material on the LC filter shown in (b). (A) is a top view which shows the modification of the sheet | seat which comprises LC filter by 1st Embodiment, (b) is a rear view. (A) is a top view which shows the modification of the sheet | seat which comprises LC filter by 2nd Embodiment, (b) is a rear view. FIG. 16 is an equivalent circuit diagram of an LC filter configured using the sheets shown in FIGS. 14 and 15.

  Next, a mode for carrying out the LC filter of the present invention and the manufacturing method thereof will be described.

  FIG. 1 is an external perspective view of an LC filter 1 according to the first embodiment.

  The LC filter 1 includes a lower base material 2 and an upper base material 3 made of a non-magnetic material or a magnetic material, and a sheet 4 having electrical insulation, and has a width W, a length L, and a thickness t. It has a rectangular parallelepiped shape. The lower base material 2 has a rack gear shape whose external appearance is shown in FIG. 2 (b), and has an uneven shape that fits from below into a rectangular bend of the sheet 4 on one surface 2b facing the bottom surface 2a. Have The outer appearance of the upper substrate 3 is shown in FIG. 2A, and has an uneven shape that fits from above into a rectangular bend of the sheet 4 on one surface 3b facing the upper surface 3a. The uneven shape formed on the lower base material 2 and the upper base material 3 is formed according to the number of turns of the coil provided in the LC filter 1 and the number of capacitors provided in the LC filter 1.

  The upper substrate 3 includes convex portions 3d and 3d at both ends so as to cover both side portions 2c and 2c of the lower substrate 2 and the crest surfaces 3c and 3c are aligned with the bottom surface 2a of the lower substrate 2. These convex parts 3d and 3d are larger than the convex part formed in the base-material center part. The length of the lower base material 2 is shorter than the length of the upper base material 3 by the amount of the convex portions 3d and 3d. The sheet 4 is made of a resin such as epoxy or polyimide, or a material such as ceramic, and is provided between the concave and convex portions of the lower base material 2 and the upper base material 3.

  FIG. 3 is a plan view before the sheet 4 is bent, and FIG. 3B is a rear view thereof. A single conductor path 5 is formed on the surface that is one surface of the sheet 4, and a plurality of capacitor electrodes 6 are formed on the back surface that is the other surface of the sheet 4. Electrode pads 5 a and 5 b are formed at both ends of the conductor path 5, and electrode pads 6 a and 6 b are formed at both ends of the plurality of capacitor electrodes 6.

  The electrode pad 5a provided at one end of the conductor path 5 and the electrode pad 6a provided at one end of the plurality of capacitor electrodes 6 are formed by vias penetrating between the front and back surfaces of the sheet 4 or the like. Are electrically connected to each other. Further, the electrode pad 5b provided at the other end of the conductor path 5 on the surface of the sheet 4 is electrically connected to the electrode pad 5c formed on the back surface of the sheet 4 by a similar via or the like. The electrode pad 5 c is provided at the other end of the conductor path 5. Accordingly, the electrode pad 5 c provided at the other end of the conductor path 5 and the electrode pad 6 b provided at the other end of the plurality of capacitor electrodes 6 are provided on one side surface of the sheet 4. The conductor path 5, the plurality of capacitor electrodes 6, and the electrode pads 5a, 5b, 5c, 6a, 6b are made of a general internal electrode material such as copper or silver, and are generally used for a printing method or a lithography technique. It is formed by the electrode forming method.

  The conductor path 5 has an amplitude with a predetermined trapezoidal wave pattern in the width W direction of the LC filter 1, and this trapezoidal wave pattern is periodically repeated in the length L direction of the LC filter 1 to form a meander shape. Yes. As shown in FIG. 1, the sheet 4 is bent at a period in which one period in which the trapezoidal wave pattern is repeated is one period in the thickness t direction, so that the conductor path 5 has a winding shape. That is, the conductor path 5 is provided meandering on one surface of the sheet 4 and exhibits a winding structure by the sheet 4 being repeatedly bent. Moreover, the sheet | seat 4 is repeatedly bent in this way, and the some capacitor electrode 6 opposes mutually.

  The above-described bending of the sheet 4 is performed with the line indicated by the alternate long and short dash line in FIG. 3 as the valley fold line v and the line indicated by the broken line as the mountain fold line m, and the valley surface V and the mountain surface M are side surfaces in the length L direction. It is performed in a cycle in which four consecutive surfaces appearing alternately through S are defined as one cycle. As shown in the schematic diagram of FIG. 4, this folding pattern has one cycle of valley fold-mountain fold-mountain fold-valley fold. In the figure, the same or corresponding parts as in FIG. The conductor path 5 has an amplitude as it approaches the side surface S of the second surface II that is next continuous in the valley surface V of the first surface I divided by the first valley fold line v among the four continuous surfaces. It swings in the width W direction where the height increases and crosses in the diagonal direction. Then, the side surface S of the next second surface II is traversed in parallel with the length L direction while maintaining the amplitude height. After that, the peak surface M of the next third surface III that is continuous with the second surface II swings in the width W direction in which the amplitude height decreases as it approaches the side surface S of the next continuous fourth surface IV, Cross diagonally. Then, the side surface S of the next fourth surface IV is traversed in parallel with the length L direction while maintaining the amplitude height.

  Accordingly, as the conductor path 5 advances in the length L direction, the bent sheet 4 descends to the valley surface V and rises to the mountain surface M in the thickness t direction of the LC filter 1. In the width W direction, the amplitude height is increased on the first surface I, maintained on the second surface II, decreased on the third surface III, and maintained on the fourth surface IV for amplitude in the width W direction. Presents.

  As shown in FIG. 6, the sheet 4 includes an electrode pad 6 a and a sheet 4 that are commonly connected to the electrode pad 5 a on the crest surfaces 3 c and 3 c of the protrusions 3 d and 3 d provided at both ends of the upper base material 3. Each electrode pad 5c, 6b provided on one side surface is exposed and bent. FIG. 6 is an external perspective view of the LC filter 1 as viewed from the bottom side. In FIG. 6, the same or corresponding parts as those in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof is omitted. Therefore, the conductor path 5 on the side surface S adjacent to the electrode pads 5a and 5b is formed longer than the length of the meander period on the other side surface S as shown in FIG. The heights of the convex portions 3d and 3d having the thickness t are substantially the same. Further, the capacitor electrode 6 on the side surface S adjacent to the electrode pads 6a and 6b is also formed longer than the width of the capacitor electrode 6 on the other side surface S, and is almost the same as the height of the convex portions 3d and 3d. ing. FIG. 5 is a perspective view of the sheet 4 in a state of being folded in this manner. In the figure, the same or corresponding parts as in FIG.

  In the present embodiment, by pressing the sheet 4 between the lower base material 2 and the upper base material 3 and pressing, the sheet 4 is bent as shown in FIG. 5, and the LC filter 1 is manufactured. At this time, an adhesive is applied to both surfaces of the sheet 4 and press working is performed. The type of adhesive used may be a general adhesive, for example, an epoxy resin adhesive.

  According to the LC filter 1 of this embodiment, the conductor path 5 meanders while alternately repeating the descending to the valley surface V and the ascent to the mountain surface M of the bent sheet 4 via the side surface S. This presents a winding structure. The capacitor electrode 6 constitutes a counter electrode of the capacitor by facing each side S. Accordingly, a single sheet 4 is simply bent at a period of four consecutive surfaces as one cycle, whereby a conductor path 5 formed on one surface of the sheet 4 is wound to form a coil, and the other The capacitor electrode 6 formed on this surface is opposed to form a capacitor, and the LC filter 1 is formed.

  In this LC filter 1, the distance between the capacitor electrodes 6 facing each other can be easily adjusted by the bending shape of the sheet 4 and the area of the capacitor electrode 6 by the pattern shape. Therefore, by securing a distance corresponding to the bending interval of the sheet 4, the breakdown voltage between the capacitor electrodes 6 can be easily ensured, and the capacitance value of the capacitor can be easily adjusted. Further, since the distance between the conductor paths 5 constituting the coil, that is, the distance between the windings, can be ensured by a distance corresponding to the bending interval of the sheet 4, a large inductance value can be obtained. For this reason, unlike the conventional LC filter disclosed in Patent Document 1 in which a pair of coils is formed on one and other surfaces of the sheet 4 and a capacitor generated between the pair of coils is a capacitor, An LC filter that is easy to adjust and has large capacitance values and inductance values can be easily obtained.

  Further, according to the LC filter 1 of the present embodiment, as shown in FIG. 3, the conductor path 5 that constitutes the coil and the capacitor electrode 6 that constitutes the capacitor are formed in a region where the sheet 4 does not overlap. The capacitor electrode 6 exists in the inner diameter portion of the coil formed by bending 4, and the capacitor electrode 6 does not block the magnetic flux passing through the inner diameter portion of the coil. For this reason, even if a coil and a capacitor are formed on one sheet 4, the coil and the capacitor can coexist on one sheet 4 without hindering the functions of the coil and the capacitor.

  In addition, according to the LC filter 1 of the present embodiment, the sheet 4 is sandwiched between the lower base material 2 and the upper base material 3 each having a concave and convex shape that fits from below and above to the bend of the sheet 4. Since the bending shape shown in FIG. 5 of the sheet 4 is maintained and the strength is ensured, the product handleability of the LC filter 1 is improved. In addition, by forming the lower base material 2 and the upper base material 3 with a material having a high insulation resistance, it is possible to easily secure a withstand voltage between the capacitor electrodes 6, and a highly reliable capacitor C and a large inductance value. The LC filter 1 having both of the coils L can be obtained.

  Further, according to the LC filter 1 of the present embodiment, the electrode pad 6a commonly connected to the electrode pad 5a and the electrode pads 5c and 6b provided on one side surface of the sheet 4 are arranged on the upper side as shown in FIG. It is exposed to the crest surfaces 3c, 3c of the convex portions 3d, 3d provided at both ends of the base material 3, and constitutes an external electrode. For this reason, unlike the conventional LC filter disclosed in Patent Document 1, the LC filter 1 can be provided with an external electrode without having any connection part between the electrode pads 5c, 6a, 6b and the pins. Further, as in the conventional LC filter disclosed in Patent Document 1, each of the crest surfaces 3c and 3c of the upper base material 3 is not required to have a man-hour for sequentially folding wide terminals protruding outward from the laminated body. The LC filter 1 can be provided with an external electrode simply by bending the sheet 4 while exposing the electrode pads 5c, 6a, 6b. Therefore, the LC filter 1 including the external electrode can be provided with high connection reliability and low cost.

  Further, the plurality of capacitor electrodes 6 constitutes a plurality of capacitors C connected in series between the electrode pads 6a and 6b provided at both ends as shown in FIG. FIG. 7 is an equivalent circuit diagram of the LC filter 1. The same or corresponding parts as those in FIG. The LC filter 1 constitutes a noise removal filter by the capacitor C and the coil L formed by the conductor path 5. For this reason, the capacitance of the LC filter 1 can also be adjusted by selecting the number of capacitors C connected in series. When the number of capacitors C connected in series is increased, the value of the capacitance is adjusted to be small.

  Further, according to the LC filter 1 of the present embodiment, as shown in FIG. 6, the electrode pads 5 c, 6 a, 6 b are exposed on one side surface of the base material constituted by the lower base material 2 and the upper base material 3. To do. The electrode pads 5c and 6a serve as hot electrodes, and a voltage is applied between the both ends of the coil L by applying a voltage between the electrode pads 5c and 6a. The electrode pad 6b serves as a ground electrode, and the electrode pad 6b is grounded, so that one end of the capacitor C connected in series is connected to the ground potential. Such an LC filter 1 is formed by mounting the base material on the circuit board so that one side surface of the base material from which the electrode pads 5c, 6a, 6b are exposed faces the circuit board surface of the circuit board (not shown). Each electrode pad 5c, 6a, 6b exposed on one side surface can be connected to each land formed on the substrate surface of the circuit board. For this reason, like the conventional LC filter disclosed in Patent Document 1, it is thin without requiring a manufacturing process for laminating a plurality of sheets, which causes an increase in product cost in order to form a laminate. The flat SMD type LC filter 1 can be provided easily and inexpensively.

  Further, in the LC filter 1 of the present embodiment, the conductor path 5 is formed so as to intersect with the folding lines v and m of the sheet 4, and the portion where the conductor path 5 is bent by the folding of the sheet 4 is the folding line v of the sea 4. , M only at the portion where the conductor path 5 intersects. For this reason, since the part by which the conductor path 5 is bent decreases, the improvement of the reliability of the conductor path 5 can be anticipated. In addition, since most of the conductor path 5 is located on the face portions of the valley surface V, the mountain surface M, and the side surface S, compared to the case where the conductor path 5 is formed along the folding lines v and m of the sheet 4, It becomes easy to form the conductor path 5 having an arbitrary width without being affected by the bending of the sheet 4. For this reason, compared with the case where the conductor path 5 is formed along the folding lines v and m of the sheet 4, the width of the conductor path 5 can be increased, and the direct current resistance value of the coil L can be easily reduced. Can be

  Further, in the LC filter 1 of the present embodiment, when the lower base material 2 and the upper base material 3 are made of a non-magnetic material or a magnetic material, and the non-magnetic material such as alumina is used, the permeability of the base material becomes small. . For this reason, since the inductance value can be kept low, the LC filter 1 for high frequency applications is provided. Further, when the lower substrate 2 and the upper substrate 3 are made of a magnetic material such as ferrite, the permeability of the substrate is increased. For this reason, the LC filter 1 having an inductance value of a desired magnitude can be obtained by selecting the type of magnetic material to be used.

  Moreover, according to the manufacturing method of the LC filter 1 of the present embodiment, the step of bending the sheet 4 to form the conductor path 5 and making the plurality of capacitor electrodes 6 face each other, the lower substrate 2 and the upper side The process of fitting the base material 3 to the strength to keep the bent shape of the sheet 4 is performed in one process of pressing the sheet 4 between the lower base material 2 and the upper base material 3 and pressing. Is called. For this reason, a manufacturing process decreases and the product cost of LC filter 1 can further be reduced.

  Moreover, according to the manufacturing method of the LC filter 1 of the present embodiment, the adhesive is applied to both sides of the sheet 4 and the above pressing is performed. Therefore, the sheet 4 is bent and the conductor path 5 is wound. A step of making a plurality of capacitor electrodes 6 face each other, a step of fitting the lower base material 2 and the upper base material 3 to a strength that maintains the bent shape of the sheet 4, and the lower base material 2 and the upper side The step of bonding the sheet 4 to the base material 3 is performed in one step of pressing the sheet 4 between the lower base material 2 and the upper base material 3 and pressing. For this reason, the manufacturing process is further reduced, and the product cost of the LC filter 1 can be further reduced.

  In the above-described embodiment, the case where the sheet 4 is folded along the valley fold line v and the mountain fold line m has been described. However, it is not always necessary to bend the sheet 4 along the fold line. By bending the sheet 4 in a wave shape or the like, the conductor path 5 formed on the sheet 4 has a winding structure and a plurality of capacitor electrodes 6 are opposed to each other. You may do it. In this case, the concavo-convex shape provided on the lower base material 2 and the upper base material 3 is not a step shape as shown in FIG.

  Further, in the above-described embodiment, the case where the structure that maintains the strength of the sheet 4 is configured by the lower base material 2 and the upper base material 3 that are fitted to the bend of the sheet 4 from below and above has been described. However, the structure which maintains the intensity | strength of the sheet | seat 4 is provided by exposing the electrode pad 5c, 6a, 6b, filling the circumference | surroundings of the sheet | seat 4 with resin, and providing the resin base material etc. which surround the circumference | surroundings of the sheet | seat 4 with resin in a rectangular parallelepiped shape. You may make it comprise. According to this configuration, the bent shape of the sheet 4 is maintained by the base material such as a resin surrounding the periphery of the sheet 4 and the strength is ensured, so that the product handleability of the LC filter 1 is also improved by this configuration.

  Moreover, the structure which maintains the intensity | strength of the sheet | seat 4 is comprised by not providing the upper side base material 3 but providing only the lower base material 2 which has the uneven | corrugated shape which fits in the curvature of the sheet | seat 4 from below on the one surface 2b. May be.

  At this time, unlike the above embodiment, the sheet 4 is turned over so that the back surface of the sheet 4 on which the capacitor electrode 6 is formed is exposed, and the fold line adjacent to the electrode pads 5a, 5b of the sheet 4 is defined as a mountain fold line m. To do. By folding in this way, as shown in the perspective view of FIG. 8A, the sheet 4 is folded into a shape in which the capacitor electrodes 6 are exposed and both end portions are folded inward. In FIG. 6A, the same or corresponding parts as those in FIG. For this reason, the external appearance of the LC filter 1A obtained by providing only the lower substrate 2 is shown in the perspective view of FIG. In FIG. 2B, the same or corresponding parts as those in FIG. In this LC filter 1A, the sheet 4 covers both side portions 2c, 2c of the lower base material 2 and both ends are bent back toward the bottom surface 2a side of the lower base material 2 so that the bottom surface 2a of the lower base material 2 is covered. The electrode pads 5c, 6a and 6b are exposed and bent.

  According to the LC filter 1A of the present configuration, the bent shape of the sheet 4 is maintained only by the lower base material 2 and the strength is ensured, so that the product handleability of the LC filter 1 is also improved by this configuration. Moreover, it is necessary to take the dimension for external electrode formation in the length L direction of LC filter 1A like the LC filter 1 shown in FIG. 1 by the sheet | seat 4 bend | folding back by the both sides of the lower base material 2. Thus, the entire length L direction of the LC filter 1A can be used to form the conductor path 5 and the capacitor electrode 6. For this reason, the acquisition efficiency of the inductance value and the capacitance value in the LC filter having the same outer dimensions and the same constituent materials can be increased.

  Further, the upper base material 3A shown in FIG. 8C is used and placed on the LC filter 1A shown in FIG. 8B, and the sheet 4 is sandwiched between the lower base material 2 and the upper base material 3A. Thus, the LC filter 1B can be formed. In the above embodiment, the upper base material 3 is provided with convex portions 3d and 3d larger than the convex portion formed at the central portion of the base material at both ends, and electrode pads are provided on the crest surfaces 3c and 3c of the convex portions 3d and 3d. 5c, 6a and 6b were exposed to form external electrodes. However, as shown in the external perspective view of FIG. 8C, an LC filter having a structure that maintains the strength of the sheet 4 even by using the upper base material 3A configured without the projections 3d and 3d. 1B is obtained, and the same operational effects as the operational effects of the LC filter 1A shown in FIG.

  FIG. 9 is an external perspective view of the LC filter 11 according to the second embodiment of the present invention.

  Similarly to the LC filter 1 according to the first embodiment, the LC filter 11 includes a lower base material 12 and an upper base material 13 made of a non-magnetic material or a magnetic material, and a sheet 14 having electrical insulation. It has a rectangular parallelepiped shape with a width W, a length L, and a thickness t. The outer appearance of the lower substrate 12 is shown in FIG. 10B, and has a concave-convex shape that fits from below into a serrated fold of the sheet 14 on one surface 12b facing the bottom surface 12a. The external appearance of the upper substrate 13 is shown in FIG. 10A, and has an uneven shape that fits from above into a serrated bend of the sheet 14 on one surface 13b facing the upper surface 13a. The uneven shape formed on the lower substrate 12 and the upper substrate 13 is formed according to the number of turns of the coil provided in the LC filter 11 and the number of capacitors provided in the LC filter 11.

  The upper base material 13 includes convex portions 13d and 13d at both ends so as to cover both side portions 12c and 12c of the lower base material 12 and the crest surfaces 13c and 13c are aligned with the bottom surface 12a of the lower base material 12. The thickness t of the LC filter 11 is the height of the convex portions 13d and 13d. The length of the lower substrate 12 is shorter than the length of the upper substrate 13 by the amount of these convex portions 13d and 13d. Similarly to the LC filter 1 according to the first embodiment, the sheet 14 is also made of a resin such as epoxy or polyimide, or a material such as ceramic, and between the concave and convex portions of the lower base material 12 and the upper base material 13. It is sandwiched and provided.

  FIG. 11A is a plan view before the sheet 14 used in the LC filter 11 according to the second embodiment is bent, and FIG. 11B is a rear view thereof. A single conductor path 15 is formed on the surface that is one surface of the sheet 14, and a capacitor electrode 16 is formed on the back surface that is the other surface of the sheet 14. Electrode pads 15 a and 15 b are formed at both ends of the conductor path 15, and electrode pads 16 a and 16 b are formed at both ends of the plurality of capacitor electrodes 16.

  The electrode pad 15a provided at one end portion of the conductor path 15 and the electrode pad 16a provided at one end portion of the plurality of capacitor electrodes 16 are formed by vias penetrating between the front surface and the back surface of the sheet 14 or the like. Are electrically connected to each other. Further, the electrode pad 15b provided at the other end of the conductor path 15 on the surface of the sheet 14 is electrically connected to the electrode pad 15c formed on the back surface of the sheet 14 by a similar via or the like. The electrode pad 15 c is provided at the other end of the conductor path 15. Therefore, the electrode pad 15 c provided at the other end of the conductor path 15 and the electrode pad 16 b provided at the other end of the plurality of capacitor electrodes 16 are provided on one side surface of the sheet 14. The conductor path 15, the plurality of capacitor electrodes 16, and the electrode pads 15a, 15b, 15c, 16a, and 16b are also made of a general internal electrode material such as copper or silver, and a general method such as a printing method or a lithography technique. It is formed by the electrode forming method.

  The conductor path 15 has an amplitude with a predetermined sine wave pattern in the width W direction of the LC filter 11, and this sine wave pattern is repeated in the length L direction of the LC filter 11 to form a meander shape. The sheet 14 is bent as shown in the perspective view of FIG. 12A at a period in which one cycle in which the sinusoidal pattern is repeated is one cycle in the thickness t direction, so that the conductor path 15 has a winding shape. The capacitor electrodes 16 are opposed to each other.

  In said 1st Embodiment, although the sheet | seat 4 was bend | folded with the period which makes four periods which the side surface S, the mountain surface M, the side surface S, and the trough surface V continue as 1 period, this 2nd Embodiment. Then, the sheet | seat 14 is bend | folded by the period which makes two continuous surfaces one cycle in which the uphill slope U and the downhill slope D appear alternately. That is, the above-described folding of the sheet 14 is performed with the folding line indicated by the alternate long and short dash line in FIG. 11 as the valley folding line v and the folding line indicated by the broken line as the mountain folding line m. The conductor path 15 is formed on the ascending slope U and the descending slope D so as to intersect the folding line of the sheet 14, and a half-cycle portion of one cycle of the sine wave amplitude pattern is formed on each of the ascending slope U and the descending slope D. Is formed. In other words, the conductor path 15 meanders on the surface of the sheet 14 with a portion formed on two continuous surfaces as one cycle. The capacitor electrode 16 is provided on every other continuous surface on the back surface of the sheet 14.

  Further, as shown in FIG. 12B, the sheet 14 is a perspective view of the appearance of the LC filter 11 viewed from the bottom surface side, and the crest surfaces 13 c of the convex portions 13 d and 13 d provided at both ends of the upper base material 13. 13c, the electrode pad 16a commonly connected to the electrode pad 15a and the electrode pads 15c and 16b provided on one side surface of the sheet 14 are exposed and bent. For this reason, the conductor path 15 adjacent to the electrode pads 15a and 15b is formed in a straight line as shown in FIG. The electrode pad 16a and the electrode pad 16b are formed to extend to the adjacent side surfaces S. The conductor path 15 on the side surface S is not necessarily formed in a straight line shape, and may be sine wave-like amplitude like the uphill slope U and downhill slope D.

  Also in the second embodiment, by pressing the sheet 14 between the lower base material 12 and the upper base material 13 and pressing, the sheet 14 is bent as shown in FIG. Is manufactured. At this time, an adhesive is applied to both surfaces of the sheet 14 and press working is performed.

  According to the LC filter 11 according to the second embodiment, the conductor path 15 meanders while alternately repeating the rising of the bent sheet 14 to the rising slope U and the lowering of the falling slope D. Presents a wound structure. The capacitor electrode 16 forms a counter electrode of the capacitor by facing through the downward slope D. Accordingly, a single sheet 14 is simply bent at a cycle of two continuous surfaces as one cycle, so that a conductor path 15 formed on one surface of the sheet 14 is wound to form a coil L. The capacitor electrode 16 formed on the other surface is opposed to form the capacitor C, and the LC filter 11 is formed. For this reason, also by the LC filter 11 according to the second embodiment, electrode pads 15c, 16a, and 16b are provided on one side surface of the base material including the lower base material 12 and the upper base material 13 shown in FIG. The SMD type thin flat LC filter 11 is obtained, and the same operational effects as the LC filter 1 according to the first embodiment are obtained.

  Further, in the LC filter 11 according to the second embodiment, the sheet 14 is bent at a cycle with two continuous surfaces as one cycle, and the conductor path 15 meanders with one cycle. As compared with the configuration of the first embodiment in which the conductor path 5 meanders in one cycle by being bent at a cycle of 1 cycle, bending per winding can be performed with a smaller number of times. For this reason, in the LC filter having the same outer dimensions, a larger number of turns can be obtained, and thus the LC filter 11 having a large inductance can be provided. Further, in the LC filter having the same number of winding coils, the number of times the sheet 14 is bent can be reduced, so that the reliability of the sheet 14 can be improved.

  In addition, by appropriately selecting the size of the width d of the conductor path 15 (see FIG. 11A) and the position where the conductor path 15 is formed on the sheet 14, the LC filter 11 having various characteristics can be easily manufactured. Can do.

  For example, by increasing the width d of the conductor path 15, the height of the conductor path 15 formed on the slope in the radial direction of the coil L increases. For this reason, the inner diameter of the wound coil L is reduced, the cross-sectional area of the inner diameter portion of the coil is reduced, and the magnetic flux is difficult to pass through the inner diameter portion of the coil. However, since the DC resistance value of the coil L is low, the LC filter 11 having the coil L that can flow a large current can be configured. On the other hand, by reducing the width d of the conductor path 15, the height of the conductor path 15 formed on the slope in the radial direction of the coil L is reduced. For this reason, since the magnitude | size of the internal diameter and internal diameter part cross-sectional area of the winding structure coil L can be ensured and a magnetic flux passes easily through a coil internal diameter part, LC filter 11 with the coil L which has high Q value is comprised. be able to. Further, by increasing the meandering amplitude of the conductor path 15, the cross-sectional area of the inner diameter portion of the wound structure coil L can be increased. For this reason, since the magnetic flux easily passes through the coil inner diameter portion, the LC filter 11 having the coil L having a higher Q value can be configured.

  In the second embodiment, the case where the structure that maintains the strength of the sheet 14 is configured by the lower base material 12 and the upper base material 13 that are fitted to the bend of the sheet 14 from below and above has been described. . However, a structure that maintains the strength of the sheet 14 by exposing the electrode pads 5c, 16a, and 16b, filling the periphery of the sheet 14 with resin, and including a resin base material that surrounds the periphery of the sheet 14 in a rectangular parallelepiped shape. You may make it comprise.

  Moreover, the structure which maintains the intensity | strength of the sheet | seat 14 is comprised by not providing the upper side base material 13 but providing only the lower side base material 12 which has the uneven | corrugated shape which fits in the curvature of the sheet | seat 14 from the one side 12b. May be.

  At this time, unlike the second embodiment, the sheet 14 is turned over so that the back surface of the sheet 14 on which the capacitor electrode 16 is formed is exposed, and the folding lines adjacent to the electrode pads 15a and 15b of the sheet 14 are folded in a mountain. Let line m. By folding in this way, as shown in the perspective view of FIG. 13A, the sheet 14 is folded into a shape in which the capacitor electrodes 16 are exposed and both end portions are folded inward. In FIG. 9A, the same or corresponding parts as in FIG. For this reason, the LC filter 11A obtained by providing only the lower substrate 12 has an appearance shown in the perspective view of FIG. In this LC filter 11A, the sheet 14 covers both side portions 12c, 12c of the lower base 12 and both ends are bent back toward the bottom surface 12a of the lower base 12 so that the bottom surface 12a of the lower base 12 is covered. The electrode pads 15c, 16a, and 16b are exposed and bent. Also with the LC filter 11A of this configuration, the bending shape of the sheet 14 is maintained only by the lower base material 12, and the strength is ensured.

  Further, using the upper base material 13A shown in FIG. 13 (c), the sheet 14 is sandwiched between the lower base material 12 and the upper base material 13A by placing it on the LC filter 11A shown in FIG. 13 (b). Thus, the LC filter 11B can be formed. In said 2nd Embodiment, it has convex parts 13d and 13d larger than the convex part formed in the base-material center part in the both ends of the upper base material 13, and the crest surfaces 13c and 13c of the convex parts 13d and 13d are provided. The electrode pads 15c, 16a, and 16b were exposed to form external electrodes. However, as shown in the external perspective view of FIG. 13 (c), an LC filter having a structure that maintains the strength of the sheet 14 even by using the upper base material 13A configured without the convex portions 13d and 13d. 11B is obtained, and the same operational effects as the operational effects of the LC filter 11A shown in FIG.

  In the first and second embodiments described above, as shown in FIGS. 3 and 11, electrode pads 6a, 6b, 16a, 16b are provided at both ends of the plurality of capacitor electrodes 6, 16, and a plurality of capacitor electrodes 6, 16 are provided. When the capacitor electrodes 6 and 16 constitute a plurality of capacitors C connected in series between the electrode pads 6a, 6b, 16a and 16b provided at both ends as shown in the equivalent circuit diagram shown in FIG. Explained. However, as shown in FIGS. 14 and 15, electrode pads 6c and 16c for commonly connecting every other one end of the plurality of capacitor electrodes 6A and 16A, and electrodes for commonly connecting the other ends of the remaining capacitor electrodes 6B and 16B. You may comprise so that the pads 6d and 16d may be provided in the both ends of the several capacitor electrodes 6 and 16. FIG. 14 and 15, the same or corresponding parts as those in FIGS. 3 and 11 are denoted by the same reference numerals, and the description thereof is omitted.

  Also in this case, the electrode pads 5a and 15a provided at one end of the conductor paths 5 and 15 and the electrode pads 6c and 16c provided at one end of the plurality of capacitor electrodes 6 and 16 are connected in common. The electrode pads 5c and 15c provided at the other end of the conductor paths 5 and 15 and the electrode pads 6d and 16d provided at the other end of the plurality of capacitor electrodes 6 and 16 are connected to the sheets 4 and 14, respectively. Provided on one side. The sheets 4 and 14 bend the electrode pads 6c and 16c connected in common and the electrode pads 5c, 6d, 15c and 16d provided on one side of the sheets 4 and 14 exposed on one side of the substrate.

  Also in this configuration, the electrode pads 6c, 16c and the electrode pads 5c, 6d, 15c, 16d provided on one side surface of the commonly connected electrode pads 6c, 16c are exposed on the surface of the base material, thereby forming an external electrode. To do. For this reason, there is no connection between the electrode pads 5c, 6c, 6d, 15c, 16c, and 16d and the pins, and the external electrode is not connected to the LC filter without requiring the steps of sequentially folding the wide terminals. The LC filter including the external electrode can be provided with high connection reliability and at low cost.

  Further, as shown in FIG. 16, the capacitor electrodes 6 and 16 constitute a plurality of capacitors C connected in parallel between the electrode pads 6c, 6d, 16c and 16d provided at both ends thereof. 16 that are the same as or correspond to those in FIGS. 14 and 15 are denoted by the same reference numerals, and description thereof is omitted. For this reason, the capacitance of the LC filter can also be adjusted by selecting the number of capacitors C connected in parallel, and the capacitance value is greatly adjusted when the number of capacitors C connected in parallel is increased.

  In each of the first and second embodiments and the modifications described above, the conductor paths 5 and 15 and the plurality of capacitor electrodes 6 and 16 are respectively connected to the sheets 4 and 14 as shown in FIGS. The case where it formed in both surfaces of one side and the other side was demonstrated. However, both the conductor paths 5 and 15 and the plurality of capacitor electrodes 6 and 16 may be formed only on one surface of the sheets 4 and 14. Even with such a configuration, the same operational effects as those of the first and second embodiments and the modifications described above can be obtained.

1, 1A, 1B, 11, 11A, 11B ... LC filter 2, 12 ... Lower substrate 2a, 12a ... Bottom surface 2b, 12b ... One surface 2c, 12c ... Side surface 3, 3A, 13, 13A ... Upper substrate 3a, 13a ... Upper surface 3b, 13b ... One surface 3c, 13c ... Mountain surface 3d, 13d ... Projection 4, 14 ... Sheet 5, 15 ... Conductor path 6, 16 ... Capacitor electrode 5a, 5b, 5c, 16a, 16b, 16c, 16d ... electrode pad v ... valley fold line m ... mountain fold line M ... mountain surface V ... valley surface U ... up slope D ... down slope S ... side

Claims (13)

A sheet having electrical insulation;
A conductor path that is provided meandering on one side of the sheet and that is repeatedly bent to provide a winding structure;
An LC filter comprising: a plurality of capacitor electrodes that are provided on the other surface of the sheet or the one surface and face each other when the sheet is repeatedly bent.   The LC filter according to claim 1, wherein the conductor path and the capacitor electrode are formed in a region where the sheet does not overlap. The sheet is folded in a cycle with four continuous surfaces as one cycle, where the valley surface and the mountain surface appear alternately via the side surfaces,
The conductor path meanders on one side of the sheet with a portion formed on four continuous surfaces as one cycle,
The LC filter according to claim 1, wherein the capacitor electrode is provided on each of the side surfaces of the other surface or the one surface of the sheet. The sheet is bent in a cycle with two continuous surfaces, each having an upward slope and a downward slope, appearing alternately,
The conductor path meanders on one side of the sheet with a portion formed on two continuous surfaces as one cycle,
3. The LC filter according to claim 1, wherein the capacitor electrode is provided on every other continuous surface of the other surface or the one surface of the sheet.   The LC filter according to claim 3, wherein the conductor path is formed so as to intersect a folding line of the sheet.   The LC filter according to any one of claims 1 to 5, further comprising a base material surrounding the periphery of the sheet.   A lower base material having a concave-convex shape that fits from below into the bending of the sheet, and an upper base material having a concave-convex shape that fits from above to the bending of the sheet. The LC filter according to any one of claims 1 to 5.   The LC filter according to claim 6 or 7, wherein the substrate is made of a non-magnetic material or a magnetic material. Electrode pads are provided at both ends of the conductor path and at both ends of the plurality of capacitor electrodes, and the electrode pads provided at one end of the conductor path and one end of the plurality of capacitor electrodes are provided. The electrode pad provided at the other end of the conductor path and the electrode pad provided at the other end of the plurality of capacitor electrodes are commonly connected to the electrode pad and one side surface of the sheet Provided in
9. The sheet according to claim 6, wherein the sheet is bent by exposing the electrode pads connected in common and the electrode pads provided on one side of the sheet to the surface of the base material. The LC filter according to any one of the above items. Electrode pads are provided at both ends of the conductor path, and electrode pads for commonly connecting every other capacitor electrode and electrode pads for commonly connecting the remaining capacitor electrodes are provided at both ends of the capacitor electrodes. The electrode pad provided at one end of the conductor path and the electrode pad provided at one end of the plurality of capacitor electrodes are commonly connected and provided at the other end of the conductor path. The electrode pad and the electrode pad provided at the other end of the plurality of capacitor electrodes are provided on one side of the sheet,
9. The sheet according to claim 6, wherein the sheet is bent by exposing the electrode pads connected in common and the electrode pads provided on one side of the sheet to the surface of the base material. The LC filter according to any one of the above items. 11. The sheet according to claim 9, wherein the sheet is bent by exposing the electrode pads commonly connected and the electrode pads provided on one side of the sheet to one side of the base material. LC filter described in 1.   The claim cited in any one of claim 7 or claim 8 to 10, wherein the sheet is bent by pressing the sheet between the lower substrate and the upper substrate. The method for producing an LC filter according to claim 9, which is cited in claim 7 or claim 11.   The method for producing an LC filter according to claim 12, wherein the pressing is performed by attaching an adhesive to both surfaces of the sheet.

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