Stacked filter

Abstract

To provide a laminated filter in which an attenuation pole can be formed into a desired shape.SOLUTION: In a laminated filter, first to fourth resonance circuits are connected to an input / output part. The input / output part includes an input / output port group which consists of an imbalanced port and a pair of balanced ports, or an input / output port group which consists of two pairs of balanced ports. The first to fourth resonance circuits respectively include an inductor conductor and first and second capacitor conductors. The inductor conductor includes first and second ends. The first capacitor conductor is connected to the first end. The second capacitor conductor is connected to the second end. The second and third resonance circuits are magnetically connected with each other. The second and third resonance circuits are arrayed between the first resonance circuit and the fourth resonance circuit in a first direction. First and second electrodes of a jumping capacitor conductor are respectively connected to the inductor conductors of the first and fourth resonance circuits.SELECTED DRAWING: Figure 1

Description

Technical Field

[0006] , , , ,

[0001] The present invention relates to a laminated filter.

Background Art

[0002] A laminated filter including a laminate and a conductor part is known (for example, Patent Document 1). The laminate has a plurality of dielectric layers laminated thereon. The conductor part is provided inside the laminate. The conductor part includes an input / output part and a plurality of resonance circuits. The input / output part includes an input / output port group composed of a plurality of ports. In the example shown in Patent Document 1, the input / output part includes an unbalanced port and a balanced port.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A balanced laminated filter is used, for example, as a bandpass filter for processing balanced signals. The balanced laminated filter includes a balance-balance filter in addition to an unbalance-balance filter such as the laminated filter described above. In a bandpass filter, if a sharp attenuation pole is formed, the filtering process can be performed more reliably. However, in a balanced laminated filter including a plurality of resonance circuits, it is difficult to adjust the attenuation pole, and it is difficult to form an attenuation pole having a desired shape.

[0005] One aspect of the present invention aims to provide a laminated filter in which an attenuation pole can be formed in a desired shape.

Means for Solving the Problems

[0006] A multilayer filter according to one aspect of the present invention comprises a laminate and a conductor. The laminate has a plurality of dielectric layers stacked on top of each other. The conductor is provided inside the laminate. The conductor includes an input / output section, first, second, third, and fourth resonant circuits, and a skip capacitor. The first, second, third, and fourth resonant circuits are connected to the input / output section. The skip capacitor connects the first resonant circuit and the fourth resonant circuit. The input / output section includes a group of input / output ports consisting of an unbalanced port and a pair of balanced ports, or a group of input / output ports consisting of two pairs of balanced ports. The first, second, third, and fourth resonant circuits each include an inductor conductor, a first capacitor conductor, and a second capacitor conductor. The inductor conductor includes first and second ends. The first capacitor conductor is connected to the first end. The second capacitor conductor is connected to the second end. In the first, second, third, and fourth resonant circuits, the second and third resonant circuits are adjacent to each other in a first direction intersecting the stacking direction of the laminate. The second and third resonant circuits are magnetically coupled to each other. The first electrode of the skip capacitor is connected to the inductor conductor of the first resonant circuit. The second electrode of the skip capacitor is connected to the inductor conductor of the fourth resonant circuit.

[0007] In this multilayer filter, the input / output section includes an input / output port group consisting of an unbalanced port and a pair of balanced ports, or an input / output port group consisting of two pairs of balanced ports. The second and third resonant circuits are adjacent to each other and are magnetically coupled to each other. A skip capacitor is connected to the inductor conductor of the first resonant circuit and the inductor conductor of the fourth resonant circuit. With this configuration in which the second and third resonant circuits are magnetically coupled, a steep attenuation pole is formed. Furthermore, the skip capacitor forms an even steeper attenuation pole.

[0008] In one embodiment described above, the first, second, third, and fourth resonant circuits may be arranged in a first direction intersecting the stacking direction of the laminate. The second and third resonant circuits are positioned between the first and fourth resonant circuits in the first direction. In this case, the characteristics of the laminated filter can be ensured while the laminated filter can be configured compactly.

[0009] In one embodiment described above, the skip capacitor may include a first skip capacitor and a second skip capacitor. The first electrode of the first skip capacitor may be connected to the first end of the first resonant circuit. The second electrode of the first skip capacitor may be connected to the first end of the fourth resonant circuit. The first electrode of the second skip capacitor may be connected to the second end of the first resonant circuit. The second electrode of the second skip capacitor may be connected to the second end of the fourth resonant circuit. In this case, an even steeper attenuation pole is formed. In particular, a steeper attenuation pole is formed in the low-frequency range. Balance characteristics may also be improved.

[0010] In one of the above embodiments, the input / output section may include a group of input / output ports consisting of an unbalanced port and a pair of balanced ports. The capacitance values ​​of the first skip capacitor and the second skip capacitor may be different from each other. In this case, the attenuation pole can be adjusted more reliably.

[0011] In one of the above embodiments, the input / output section may include a group of input / output ports consisting of two pairs of balanced ports. The capacitance values ​​of the first skip capacitor and the second skip capacitor may be equivalent to each other. In this case, the attenuation pole can be adjusted more reliably.

[0012] In one embodiment described above, the multilayer filter further comprises a capacitor conductor connecting the inductor conductor of the second resonant circuit and the inductor conductor of the third resonant circuit. In this case, the attenuation pole can be adjusted more easily.

[0013] In one embodiment described above, the inductor conductor of the fourth resonant circuit may include first and second inductor conductors electrically connected to each other. The first inductor conductor may include a first end and a third end. The third end is connected to the second inductor conductor. The second inductor conductor may include a second end and a fourth end. The fourth end may be connected to the third end of the first inductor conductor. A pair of balanced ports included in the input / output section may include a balanced port connected to the first end and a balanced port connected to the second end. The third and fourth ends may be connected to external terminals. In this case, for example, a ground terminal or an RF ground terminal may be connected to the external terminals. As a result, the attenuation pole can be adjusted more reliably. [Effects of the Invention]

[0014] One aspect of the present invention aims to provide a multilayer filter in which the attenuation pole can be formed in a desired shape. [Brief explanation of the drawing]

[0015] [Figure 1] This is a perspective view of the stacked filter in this embodiment. [Figure 2] This is a perspective view of a stacked filter. [Figure 3] This is a circuit diagram of a stacked filter. [Figure 4] This is a perspective view of a stacked filter in a modified example of this embodiment. [Figure 5] This is a perspective view of a stacked filter in a modified example of this embodiment. [Figure 6] This is a circuit diagram of a stacked filter in a modified example of this embodiment. [Figure 7] This figure shows the characteristics of the stacked filter in this embodiment. [Figure 8] This diagram shows the characteristics of a stacked filter. [Figure 9] This diagram shows the characteristics of a stacked filter. [Figure 10] This diagram shows the characteristics of a stacked filter. [Figure 11] It is a diagram showing the characteristics of the multilayer filter. [Figure 12] It is a diagram showing the characteristics of the multilayer filter.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted. [[ID=​​​​​​​​​​The laminate 3 is, for example, insulating. The laminate 3 is composed of, for example, a magnetic material. The magnetic material includes, for example, at least one selected from Ni-Cu-Zn ferrite material, Ni-Cu-Zn-Mg ferrite material, and Ni-Cu ferrite material. The magnetic material constituting the laminate 3 may include Fe alloys, etc. The laminate 3 may be composed of a non-magnetic material. The non-magnetic material includes, for example, at least one selected from glass ceramic material and dielectric material.

[0020] The laminate 3 has, for example, a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and edges, and a rectangular parallelepiped shape with rounded corners and edges. The shape of the laminate 3 is not limited to a rectangular parallelepiped shape. In this embodiment, the Z-axis direction corresponds to the height direction of the laminate 3, and the X-axis direction and Y-axis direction correspond to the short side and long side direction of the laminate 3. For example, the length in the height direction of the laminate 3 is shorter than the length in the short side direction of the laminate 3.

[0021] The laminate 3 has a pair of main surfaces 2a, 2b, a pair of end surfaces 2c, 2d, and a pair of side surfaces 2e, 2f as its outer surface. The pair of main surfaces 2a, 2b face each other in the Z-axis direction. The pair of end surfaces 2c, 2d face each other in the Y-axis direction. The pair of side surfaces 2e, 2f face each other in the X-axis direction. The pair of main surfaces 2a, 2b, the pair of end surfaces 2c, 2d, and the pair of side surfaces 2e, 2f are, for example, planes. The pair of main surfaces 2a are, for example, aligned with the X-axis and Y-axis directions. The pair of end surfaces 2c, 2d are, for example, aligned with the X-axis and Z-axis directions. The pair of side surfaces 2e, 2f are, for example, aligned with the Y-axis and Z-axis directions.

[0022] The main surface 2b is defined as the mounting surface that faces other electronic devices when mounting the device on other electronic devices, for example. The main surface 2a corresponds to the opposing surface that faces the main surface 2b in the Z-axis direction.

[0023] The laminate 3 includes multiple dielectric layers. In the laminate 3, the multiple dielectric layers are stacked in the Z-axis direction. In other words, the Z-axis direction corresponds to the stacking direction of the multiple dielectric layers. Each dielectric layer corresponds to an insulating layer. Each dielectric layer is composed of, for example, a sintered body of a ceramic green sheet containing a dielectric material. The dielectric material includes, for example, at least one selected from BaTiO3-based materials, Ba(Ti,Zr)O3-based materials, (Ba,Ca)TiO3-based materials, glass materials, or alumina materials.

[0024] In the example shown in this embodiment, the length of the laminate 3 in the X-axis direction is 1.25 mm. The length of the laminate 3 in the Y-axis direction is 2.00 mm. The length of the laminate 3 in the Z-axis direction is 0.95 mm.

[0025] The conductor portion 5 is provided on the outer surface of the laminate 3. The conductor portion 5 is formed by known methods. The conductor portion 5 is made of, for example, a metallic material. The metallic material is, for example, copper, silver, gold, nickel, or chromium. The conductor portion 5 is formed, for example, by plating the electrode layer. The electrode layer consists of, for example, a conductive paste. The conductive paste is applied, for example, by printing or transfer. The plating process is, for example, electroplating or electroless plating. This plating process forms a plating layer on the outer surface of the conductive paste.

[0026] The conductor portion 5 includes a plurality of external electrodes 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, and 5i that are spaced apart from each other. The external electrodes 5a to 5i are each connected to the conductor portion 6. The external electrodes 5a to 5i are each provided on the main surface 2b. The external electrodes 5a to 5i are each rectangular in shape. In this specification, "connected" means connected in a state of direct contact. "Direct contact" means connected to each other without the use of other members shown in this specification. "Direct contact" does not exclude connection via members not explicitly shown in this specification.

[0027] The conductor section 6 is located inside the laminate 3. The conductor section 6 includes an input / output section 10, an external terminal 15, and a plurality of electrical circuits 20. The plurality of electrical circuits 20 are electromagnetically connected to each other inside the laminate 3, forming a single filter circuit. In this specification, "electromagnetic connection" includes electrical connections and magnetic connections. "Electrical connection" includes connections through which DC components are transmitted, and connections through which only AC components are transmitted without transmitting DC components. In this specification, an electrical connection is also simply referred to as a "connection".

[0028] The input / output unit 10 transmits the input signal through a plurality of electrical circuits 20 and outputs the signals transmitted from the plurality of electrical circuits 20. For example, the input / output unit 10 receives a signal from outside the stacked filter 1 and outputs a signal to the outside of the stacked filter 1. The input / output unit 10 includes a group of input / output ports consisting of an unbalanced port 11 and a pair of balanced ports 13 and 14. The pair of balanced ports 13 and 14 input and output balanced signals. In other words, the signals input and output to balanced port 13 and the signals input and output to balanced port 14 have opposite polarities.

[0029] Multiple electrical circuits 20 are connected to the input / output unit 10. Multiple electrical circuits 20 are electromagnetically connected to each other. Multiple electrical circuits 20 include multiple resonant circuits. Multiple electrical circuits 20 include electrical circuits 21, 22, 23, 24, 25, 26, 27, 28, 29, and 30. Electrical circuits 21, 22, 23, and 24 include resonant circuits. Electrical circuits 21, 22, 23, and 24 are, for example, LC resonant circuits. Each electrical circuit 21, 22, 23, and 24 forms an inductor and a capacitor. In electrical circuits 21, 22, 23, and 24, electrical circuits 22 and 23 are adjacent to each other in a direction intersecting the stacking direction of the laminate 3 and are magnetically coupled to each other. In the example shown in this embodiment, multiple electrical circuits 21, 22, 23, and 24 are arranged in a direction intersecting the stacking direction of the laminate 3. Multiple electrical circuits 21, 22, 23, and 24 are arranged in the X-axis direction. Electrical circuits 22 and 23 are arranged between electrical circuit 21 and electrical circuit 24 in the X-axis direction. Multiple electrical circuits 21, 22, 23, and 24 are electromagnetically connected to each other.

[0030] Electrical circuits 21, 22, 23, 24, 25, 26, 27, 28, 29, and 30 are separated from each other. In this specification, when "separated" is used in relation to electrical circuits, "separated" means a state in which they are not physically connected by a conductor and therefore DC components are not transmitted. Electrical circuits 21, 22, 23, 24, 25, 26, 27, 28, 29, and 30 are electrically connected to each other.

[0031] Each electrical circuit 20 is composed of multiple conductors. The conductors constituting each electrical circuit 20 include, for example, at least one selected from Ag and Pd. A plating layer is formed on the surface of each terminal electrode. The plating layer is formed, for example, by electroplating. The plating layer has a layer structure consisting of a Cu plating layer, a Ni plating layer, and a Sn plating layer, or a layer structure consisting of a Ni plating layer and a Sn plating layer.

[0032] As shown in Figure 3, the electrical circuit 21 includes an inductor conductor 41 and capacitor conductors 51a, 51b, 51c, 51d, 51e, and 51f. The inductor conductor 41 corresponds to a coil. The inductor conductor 41 includes a pair of ends 41a and 41b. The inductor conductor 41 forms an inductor. The capacitor conductors 51a, 51b, 51c, 51d, 51e, and 51f form a capacitor. In the electrical circuit 21, the end 41a and the capacitor conductors 51a, 51b, and 51c are electrically connected to each other. The unbalanced port 11 and the end 41a are electrically connected to each other. In the electrical circuit 21, the end 41b and the capacitor conductors 51d, 51e, and 51f are electrically connected to each other.

[0033] In the multilayer filter 1, the electrical circuit 21 corresponds to at least a part of the first resonant circuit. Capacitor conductors 51a and 51b correspond to the first capacitor conductors that form the first capacitor. Capacitor conductor 51c corresponds to a skip capacitor conductor that forms a skip capacitor. For example, capacitor conductor 51c corresponds to the first skip capacitor conductor that forms the first skip capacitor. The first skip capacitor conductor corresponds to the first electrode of a pair of electrodes that form the first skip capacitor.

[0034] Capacitor conductors 51d and 51e correspond to second capacitor conductors forming a second capacitor. Capacitor conductor 51f corresponds to a skip capacitor conductor forming a skip capacitor. For example, capacitor conductor 51f corresponds to a second skip capacitor conductor forming a second skip capacitor. The second skip capacitor conductor corresponds to the first electrode of a pair of electrodes forming the second skip capacitor.

[0035] The electrical circuit 22 includes an inductor conductor 42 that forms an inductor and capacitor conductors 52a, 52b, 52c, 52d, 52e, 52f that form a capacitor. The inductor conductor 42 corresponds to a coil. The inductor conductor 42 includes a pair of ends 42a, 42b. The inductor conductor 42 forms an inductor. Electrical circuits 21 and 22 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 51b and capacitor conductor 52b. Capacitor conductors 52a, 52b, 52c, 52d, 52e, 52f form a capacitor. In the electrical circuit 22, the end 42a and capacitor conductors 52a, 52b, 52c are electrically connected to each other. In the electrical circuit 22, the end 42b and capacitor conductors 52d, 52e, 52f are electrically connected to each other. In the multilayer filter 1, the electrical circuit 22 corresponds to at least a part of the second resonant circuit. Capacitor conductors 52a, 52b, and 52c correspond to first capacitor conductors that form the first capacitor. Capacitor conductors 52d, 52e, and 52f correspond to second capacitor conductors that form the second capacitor.

[0036] The electrical circuit 23 includes an inductor conductor 43 that forms an inductor and capacitor conductors 53a, 53b, 53c, 53d, 53e, 53f that form a capacitor. The inductor conductor 43 corresponds to a coil. The inductor conductor 43 includes a pair of ends 432a, 43b. The inductor conductor 43 forms an inductor. The capacitor conductors 53a, 53b, 53c, 53d, 53e, 53f form a capacitor. In the electrical circuit 23, the end 43a and the capacitor conductors 53a, 53b, 53c are electrically connected to each other. In the electrical circuit 23, the end 43b and the capacitor conductors 53d, 53e, 53f are electrically connected to each other.

[0037] In the multilayer filter 1, the electrical circuit 23 corresponds to at least a part of the third resonant circuit. Capacitor conductors 53a, 53b, and 53c correspond to the first capacitor conductors that form the first capacitor. Capacitor conductors 53d, 53e, and 53f correspond to the second capacitor conductors that form the second capacitor.

[0038] The electrical circuit 24 includes an inductor conductor 44 that forms an inductor and capacitor conductors 54a, 54b, 54c, 54d, 54e, and 54f that form a capacitor. The inductor conductor 44 includes an inductor conductor 45 and an inductor conductor 46 that are electrically connected to each other. The inductor conductors 45 and 46 correspond to coils. The inductor conductor 45 includes a pair of ends 45a and 45b. The inductor conductor 46 includes a pair of ends 46a and 46b. The end 45b of the inductor conductor 45 and the end 46b of the inductor conductor 46 are connected to each other.

[0039] Inductor conductors 45 and 46 form an inductor. Capacitor conductors 54a, 54b, 54c, 54d, 54e, and 54f form a capacitor. In the electrical circuit 24, terminal 45a and capacitor conductors 54a, 54b, and 54c are electrically connected to each other. The balanced port 13 and terminal 45a are electrically connected to each other. In the electrical circuit 24, terminals 45b, 46b, and the external terminal 15 are electrically connected to each other. In the electrical circuit 24, terminal 46a and capacitor conductors 54d, 54e, and 54f are electrically connected to each other. The balanced port 14 and terminal 46a are electrically connected to each other.

[0040] In the multilayer filter 1, the electrical circuit 24 corresponds to at least a part of the fourth resonant circuit. Capacitor conductors 54a and 54b correspond to the first capacitor conductors that form the first capacitor. Capacitor conductor 54c corresponds to a skip capacitor conductor that forms a skip capacitor. For example, capacitor conductor 53c corresponds to the first skip capacitor conductor that forms the first skip capacitor. The first skip capacitor conductor corresponds to the second electrode of a pair of electrodes that form the first skip capacitor.

[0041] Capacitor conductors 54d and 54e correspond to second capacitor conductors forming a second capacitor. Capacitor conductor 54f corresponds to a skip capacitor conductor forming a skip capacitor. For example, capacitor conductor 54f corresponds to a second skip capacitor conductor forming a second skip capacitor. The second skip capacitor conductor corresponds to the second electrode of a pair of electrodes forming the second skip capacitor.

[0042] Electrical circuit 25 includes capacitor conductors 55a and 55b that form a capacitor. Electrical circuit 22 and electrical circuit 25 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 52c and capacitor conductor 55a. Electrical circuit 23 and electrical circuit 25 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 53b and capacitor conductor 55b. In electrical circuit 25, capacitor conductor 55a and capacitor conductor 55b are electrically connected to each other.

[0043] Electrical circuit 26 includes capacitor conductors 56a and 56b that form a capacitor. Electrical circuit 21 and electrical circuit 26 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 51c and capacitor conductor 56a. Electrical circuit 24 and electrical circuit 26 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 54c and capacitor conductor 56b. In electrical circuit 26, capacitor conductor 56a and capacitor conductor 56b are electrically connected to each other.

[0044] A jump capacitor is formed by the electrical circuit 26 and the capacitor conductors 51c and 54c. For example, a first jump capacitor is formed by the electrical circuit 26 and the capacitor conductors 51c and 54c. This first jump capacitor jumps over electrical circuits 22 and 23, which are adjacent to each other in the X-axis direction, and connects electrical circuits 21 and 24. In other words, this first jump capacitor connects electrical circuits 21 and 24, which are arranged so as to sandwich electrical circuits 22 and 23, which are magnetically coupled to each other, in the X-axis direction.

[0045] Electrical circuit 27 includes capacitor conductors 57a and 57b that form a capacitor. Electrical circuit 21 and electrical circuit 27 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 51f and capacitor conductor 57a. Electrical circuit 24 and electrical circuit 27 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 54f and capacitor conductor 57b. In electrical circuit 27, capacitor conductor 57a and capacitor conductor 57b are electrically connected to each other.

[0046] A jump capacitor is formed by the electrical circuit 27 and the capacitor conductors 51f and 54f. For example, a second jump capacitor is formed by the electrical circuit 27 and the capacitor conductors 51f and 54f. This second jump capacitor jumps over electrical circuits 22 and 23, which are adjacent to each other in the X-axis direction, and connects electrical circuits 21 and 24. In other words, this second jump capacitor connects electrical circuits 21 and 24, which are arranged so as to sandwich electrical circuits 22 and 23, which are magnetically coupled to each other, in the X-axis direction. In the multilayer filter 1, the capacitance of the first jump capacitor and the capacitance of the second jump capacitor are different from each other.

[0047] Electrical circuit 28 includes capacitor conductors 58a and 58b that form a capacitor. Electrical circuit 22 and electrical circuit 28 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 52f and capacitor conductor 58a. Electrical circuit 23 and electrical circuit 28 are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 53e and capacitor conductor 58b. In electrical circuit 28, capacitor conductor 58a and capacitor conductor 58b are electrically connected to each other.

[0048] Electrical circuit 29 includes capacitor conductors 59a, 59b, 59c, and 59d that form a capacitor. Electrical circuit 21 and electrical circuit 29 are connected to each other by AC coupling. Electrical circuit 22 and electrical circuit 29 are connected to each other by AC coupling. Electrical circuit 23 and electrical circuit 29 are connected to each other by AC coupling. Electrical circuit 24 and electrical circuit 29 are connected to each other by AC coupling. In electrical circuit 29, capacitor conductors 59a, 59b, 59c, and 59d are connected to ground. A capacitor is formed by capacitor conductor 51a and capacitor conductor 59a. A capacitor is formed by capacitor conductor 52a and capacitor conductor 59b. A capacitor is formed by capacitor conductor 53a and capacitor conductor 59c. A capacitor is formed by capacitor conductor 54a and capacitor conductor 59d.

[0049] Electrical circuit 30 includes capacitor conductors 60a, 60b, 60c, and 60d that form a capacitor. Electrical circuit 21 and electrical circuit 30 are connected to each other by AC coupling. Electrical circuit 22 and electrical circuit 30 are connected to each other by AC coupling. Electrical circuit 23 and electrical circuit 30 are connected to each other by AC coupling. Electrical circuit 24 and electrical circuit 30 are connected to each other by AC coupling. In electrical circuit 30, capacitor conductors 60a, 60b, 60c, and 60d are connected to ground. A capacitor is formed by capacitor conductor 51d and capacitor conductor 60a. A capacitor is formed by capacitor conductor 52d and capacitor conductor 60b. A capacitor is formed by capacitor conductor 53d and capacitor conductor 60c. A capacitor is formed by capacitor conductor 54d and capacitor conductor 60d.

[0050] As shown in Figure 2, the inductor conductors 41, 42, 43, 45, and 46 are arranged inside the laminate 3. The inductor conductors 41, 42, 43, 45, and 46 have coil axes aligned with a direction perpendicular to the lamination direction. The inductor conductors 41, 42, 43, 45, and 46 have coil axes aligned with the X-axis direction.

[0051] In this embodiment, the inductor conductors 41, 42, 43, 45, and 46 are single-turn coils. Each of the inductor conductors 41, 42, 43, 45, and 46 includes, for example, at least one conductor layer 71 and a plurality of connecting conductors 72. The conductor layer 71 extends along the dielectric layers of the laminate 3. The conductor layer 71 is sandwiched between a pair of dielectric layers. The conductor layer 71 includes a pair of ends 71a and 71b located opposite each other.

[0052] Each of the multiple connecting conductors 72 is connected to the conductor layer 71. Each connecting conductor 72 extends in the Z-axis direction. Each connecting conductor 72 is formed by multiple vias 79 that penetrate the dielectric layer. In other words, the inductor conductors 41, 42, 43, 45, and 46 each include the conductor layer 71 and multiple vias 79. The multiple vias 79 are electrically connected to the corresponding conductor layer among the multiple conductor layers 71. The multiple vias 79 are arranged in the stacking direction. Each of the multiple connecting conductors 72 includes a connecting conductor 72 connected to end 71a and a connecting conductor 72 connected to end 71b.

[0053] For example, external electrode 5a is connected to the unbalanced port 11 and, through the unbalanced port 11, is connected to the connecting conductor 72 of the end 41a of the inductor conductor 41. External electrode 5b is connected to the balanced port 13A and, through the balanced port 13, is connected to the connecting conductor 72 of the end 45a of the inductor conductor 45. External electrode 5c is connected to the balanced port 14 and, through the balanced port 14, is connected to the connecting conductor 72 of the end 41b of the inductor conductor 46. External electrode 5d corresponds to the external terminal 15 of the electrical circuit 24. External electrodes 5e, 5f, 5g, 5h, and 5i are connected to capacitor conductors 59a, 59b, 59c, and 59d, and capacitor conductors 60a, 60b, 60c, and 60d.

[0054] Next, a modified example of the multilayer filter in this embodiment will be described with reference to Figures 4 to 6. Figure 4 is a perspective view of the multilayer filter in the modified example of this embodiment. Figure 5 is a perspective view of the multilayer filter in this modified example. Figure 6 is a circuit diagram of the multilayer filter in this modified example. This modified example is generally similar to or the same as the embodiment described above. This modified example differs from the embodiment described above in that the multilayer filter includes a bandpass filter with balanced characteristics. The differences between the embodiment described above and this modified example will be mainly described below.

[0055] In this modified example, the stacked filter 1A includes a bandpass filter having a balanced-balanced characteristic. The stacked filter 1A has conductor sections 5A and 6A instead of conductor sections 5 and 6. As shown in Figure 4, conductor section 5A includes three pairs of spaced-apart external electrodes 85a, 85b, and 85c. The three pairs of external electrodes 85a, 85b, and 85c are each connected to conductor section 6A.

[0056] One of each pair of external electrodes 85a, 85b, and 85c is provided on the side surface 2e and the main surfaces 2a and 2b, respectively, and is arranged in the Y-axis direction. One of each pair of external electrodes 85a, 85b, and 85c extends between the main surfaces 2a and 2b in the Z-axis direction. The other of each pair of external electrodes 85a, 85b, and 85c is provided on the side surface 2f and the main surfaces 2a and 2b, respectively, and is arranged in the X-axis direction. The other of each pair of external electrodes 85a, 85b, and 85c extends between the main surfaces 2a and 2b in the Z-axis direction.

[0057] The conductor section 6A is located inside the laminate 3. The conductor section 6A includes an input / output section 10A and a plurality of electrical circuits 20A. The plurality of electrical circuits 20A are electromagnetically connected to each other inside the laminate 3, forming a single filter circuit.

[0058] The input / output unit 10A transmits the input signal through multiple electrical circuits 20A and outputs the signals transmitted from the multiple electrical circuits 20A. For example, the input / output unit 10A receives a signal from outside the stacked filter 1A and outputs a signal to the outside of the stacked filter 1A. The input / output unit 10A includes an input / output port group consisting of two pairs of balanced ports 11A, 12A, 13A, and 14A. The pair of balanced ports 13A and 14A output balanced signals. In other words, the signals input and output to balanced port 13A and the signals input and output to balanced port 14A have opposite polarities.

[0059] Multiple electrical circuits 20A are connected to the input / output unit 10. Multiple electrical circuits 20A are electromagnetically connected to each other. Multiple electrical circuits 20 include multiple resonant circuits. Multiple electrical circuits 20 include electrical circuits 21A, 22A, 23A, 24A, 25A, 26A, 27A, 28A, 29A, 30A, 31A, and 32A. Electrical circuits 21A, 22A, 23A, and 24A include resonant circuits. Electrical circuits 21A, 22A, 23A, and 24A are, for example, LC resonant circuits. Each electrical circuit 21A, 22A, 23A, and 24A forms an inductor and a capacitor. In electrical circuits 21A, 22A, 23A, and 24A, electrical circuits 22A and 23A are adjacent to each other in a direction intersecting the stacking direction of the laminate 3 and are magnetically coupled to each other. In this modified example, the multiple electrical circuits 21A, 22A, 23A, and 24A are arranged in a direction intersecting the stacking direction of the laminate 3. The multiple electrical circuits 21A, 22A, 23A, and 24A are arranged in the X-axis direction. Electrical circuits 22A and 23A are arranged between electrical circuit 21A and electrical circuit 24A in the X-axis direction. The multiple electrical circuits 21A, 22A, 23A, and 24A are electromagnetically connected to each other.

[0060] Electrical circuits 21A, 22A, 23A, 24A, 25A, 26A, 27A, 28A, 29A, 30A, 31A, and 32A are separated from each other. Electrical circuits 21A, 22A, 23A, 24A, 25A, 26A, 27A, 28A, 29A, 30A, 31A, and 32A are electrically connected to each other.

[0061] Each electrical circuit 20A is composed of multiple conductors. Each electrical circuit 20A comprises at least one selected from, for example, Ag and Pd. A plating layer is formed on the surface of each terminal electrode. The plating layer is formed, for example, by electroplating. The plating layer has a layer structure consisting of a Cu plating layer, a Ni plating layer, and a Sn plating layer, or a layer structure consisting of a Ni plating layer and a Sn plating layer.

[0062] As shown in Figure 6, the electrical circuit 21A includes an inductor conductor 41A and capacitor conductors 91a, 91b, 91c, 91d, 91e, and 91f. The inductor conductor 41A corresponds to a coil. The inductor conductor 41A includes a pair of ends 41a and 41b. The inductor conductor 41A forms an inductor. The capacitor conductors 91a, 91b, 91c, 91d, 91e, and 91f form a capacitor. In the electrical circuit 21A, the end 41a and the capacitor conductors 91a, 91b, and 91c are electrically connected to each other. The balanced port 11A and the end 41a are electrically connected to each other. In the electrical circuit 21, the end 41b and the capacitor conductors 91d, 91e, and 91f are electrically connected to each other.

[0063] In the multilayer filter 1A, the electrical circuit 21A corresponds to at least a part of the first resonant circuit. Capacitor conductors 91a and 91b correspond to the first capacitor conductors forming the first capacitor. Capacitor conductor 91c corresponds to a skip capacitor conductor forming a skip capacitor. For example, capacitor conductor 91c corresponds to the first skip capacitor conductor forming the first skip capacitor. The first skip capacitor conductor corresponds to the first electrode of a pair of electrodes forming the first skip capacitor.

[0064] Capacitor conductors 91d and 91e correspond to the second capacitor conductors that form the second capacitor. Capacitor conductor 91f corresponds to the skip capacitor conductor that forms the skip capacitor. For example, capacitor conductor 91f corresponds to the second skip capacitor conductor that forms the second skip capacitor. The second skip capacitor conductor corresponds to the first electrode of the pair of electrodes that form the second skip capacitor.

[0065] Electrical circuit 22A includes an inductor conductor 42A that forms an inductor and capacitor conductors 92a, 92b, 92c, 92d, 92e, 92f that form a capacitor. The inductor conductor 42A corresponds to a coil. The inductor conductor 42A includes a pair of ends 42a, 42b. The inductor conductor 42A forms an inductor. Electrical circuits 21A and 22A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 91a and capacitor conductor 92a. Capacitor conductors 92a, 92b, 92c, 92d, 92e, 92f form a capacitor.

[0066] In the electrical circuit 22A, terminal 42a and capacitor conductors 92a, 92b, and 92c are electrically connected to each other. In the electrical circuit 22A, terminal 42b and capacitor conductors 92d, 92e, and 92f are electrically connected to each other. In the multilayer filter 1, the electrical circuit 22A corresponds to at least a part of the second resonant circuit. Capacitor conductors 92a, 92b, and 92c correspond to the first capacitor conductors that form the first capacitor. Capacitor conductors 92d, 92e, and 92f correspond to the second capacitor conductors that form the second capacitor.

[0067] The electrical circuit 23A includes an inductor conductor 43A that forms an inductor and capacitor conductors 93a, 93b, 93c, 93d, 93e, 93f that form a capacitor. The inductor conductor 43A corresponds to a coil. The inductor conductor 43A includes a pair of ends 432a, 43b. The inductor conductor 43A forms an inductor. The capacitor conductors 93a, 93b, 93c, 93d, 93e, 93f form a capacitor. In the electrical circuit 23A, the end 43a and the capacitor conductors 93a, 93b, 93c are electrically connected to each other. In the electrical circuit 23A, the end 43b and the capacitor conductors 93d, 93e, 93f are electrically connected to each other.

[0068] In the multilayer filter 1A, the electrical circuit 23A corresponds to at least a part of the third resonant circuit. Capacitor conductors 93a, 93b, and 93c correspond to the first capacitor conductors forming the first capacitor. Capacitor conductors 93d, 93e, and 93f correspond to the second capacitor conductors forming the second capacitor.

[0069] The electrical circuit 24A includes an inductor conductor 44A that forms an inductor and capacitor conductors 94a, 94b, 94c, 94d, 94e, 94f that form a capacitor. The inductor conductor 44A includes a pair of ends 44a, 44b. The inductor conductor 44A forms an inductor. The capacitor conductors 94a, 94b, 94c, 94d, 94e, 94f form a capacitor. In the electrical circuit 24A, the end 44a and the capacitor conductors 94a, 94b, 94c are electrically connected to each other. The balanced port 13A and the end 44a are electrically connected to each other. In the electrical circuit 24A, the end 44b and the capacitor conductors 94d, 94e, 94f are electrically connected to each other. The balanced port 14A and the end 44b are electrically connected to each other.

[0070] In the multilayer filter 1A, the electrical circuit 24A corresponds to at least a part of the fourth resonant circuit. Capacitor conductors 94a and 94b correspond to the first capacitor conductors forming the first capacitor. Capacitor conductor 94c corresponds to a skip capacitor conductor forming a skip capacitor. For example, capacitor conductor 94c corresponds to the first skip capacitor conductor forming the first skip capacitor. The first skip capacitor conductor corresponds to the second electrode of a pair of electrodes forming the first skip capacitor.

[0071] Capacitor conductors 94d and 94e correspond to the second capacitor conductors that form the second capacitor. Capacitor conductor 94f corresponds to the skip capacitor conductor that forms the skip capacitor. For example, capacitor conductor 94f corresponds to the second skip capacitor conductor that forms the second skip capacitor. The second skip capacitor conductor corresponds to the second electrode of the pair of electrodes that form the second skip capacitor.

[0072] Electrical circuit 25A includes capacitor conductors 95a and 95b that form a capacitor. Electrical circuit 22A and electrical circuit 25A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 91c and capacitor conductor 95a. Electrical circuit 23A and electrical circuit 25A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 91e and capacitor conductor 95b. In electrical circuit 25A, capacitor conductor 95a and capacitor conductor 95b are electrically connected to each other.

[0073] Electrical circuit 26A includes capacitor conductors 96a and 96b that form a capacitor. Electrical circuit 21A and electrical circuit 26A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 92b and capacitor conductor 96a. Electrical circuit 24A and electrical circuit 26A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 92e and capacitor conductor 96b. In electrical circuit 26A, capacitor conductor 96a and capacitor conductor 96b are electrically connected to each other.

[0074] Electrical circuit 27A includes capacitor conductors 97a and 97b that form a capacitor. Electrical circuit 21A and electrical circuit 27A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 93b and capacitor conductor 97a. Electrical circuit 24A and electrical circuit 27A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 93f and capacitor conductor 97b. In electrical circuit 27A, capacitor conductor 97a and capacitor conductor 97b are electrically connected to each other.

[0075] Electrical circuit 28A includes capacitor conductors 98a and 98b that form a capacitor. Electrical circuit 22A and electrical circuit 28A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 94b and capacitor conductor 98a. Electrical circuit 23A and electrical circuit 28A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 94e and capacitor conductor 98b. In electrical circuit 28A, capacitor conductor 98a and capacitor conductor 98b are electrically connected to each other.

[0076] Electrical circuit 29A includes capacitor conductors 99a and 99b that form a capacitor. Electrical circuit 21A and electrical circuit 29A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 91c and capacitor conductor 99a. Electrical circuit 24A and electrical circuit 28A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 94c and capacitor conductor 99b. In electrical circuit 29A, capacitor conductor 99a and capacitor conductor 99b are electrically connected to each other.

[0077] A jump capacitor is formed by the electrical circuit 29A and the capacitor conductors 91c and 94c. For example, a first jump capacitor is formed by the electrical circuit 29A and the capacitor conductors 91c and 94c. This first jump capacitor jumps over electrical circuits 22A and 23A, which are adjacent to each other in the X-axis direction, and connects electrical circuits 21A and 24A. In other words, this first jump capacitor connects electrical circuits 21A and 24A, which are arranged so as to sandwich electrical circuits 22A and 23A, which are magnetically coupled to each other, in the X-axis direction.

[0078] Electrical circuit 30A includes capacitor conductors 100a and 100b that form a capacitor. Electrical circuit 21A and electrical circuit 30A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 91f and capacitor conductor 100a. Electrical circuit 24A and electrical circuit 30A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 94f and capacitor conductor 100b. In electrical circuit 30A, capacitor conductor 100a and capacitor conductor 100b are electrically connected to each other.

[0079] A jump capacitor is formed by the electrical circuit 30A and the capacitor conductors 91f and 94f. For example, a second jump capacitor is formed by the electrical circuit 30A and the capacitor conductors 91f and 94f. This second jump capacitor jumps over electrical circuits 22A and 23A, which are adjacent to each other in the X-axis direction, and connects electrical circuits 21A and 24A. In other words, this second jump capacitor connects electrical circuits 21A and 24A, which are arranged so as to sandwich the magnetically coupled electrical circuits 22A and 23A in the X-axis direction. In the multilayer filter 1A, the capacitance of the first jump capacitor and the capacitance of the second jump capacitor are equivalent. Here, in this specification, "equal capacitance" means that the capacitance value of one is within ±20% of the capacitance value of the other.

[0080] Electrical circuit 31A includes capacitor conductors 101a and 101b that form a capacitor. Electrical circuit 22A and electrical circuit 31A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 92c and capacitor conductor 101a. Electrical circuit 23A and electrical circuit 31A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 93c and capacitor conductor 101b. In electrical circuit 31A, capacitor conductor 101a and capacitor conductor 101b are electrically connected to each other. In electrical circuit 31A, capacitor conductors 101a and 101b are connected to ground.

[0081] Electrical circuit 32A includes capacitor conductors 102a and 102b that form a capacitor. Electrical circuit 22A and electrical circuit 32A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 92f and capacitor conductor 102a. Electrical circuit 23A and electrical circuit 32A are connected to each other by AC coupling. A capacitor is formed by capacitor conductor 93f and capacitor conductor 102b. In electrical circuit 32A, capacitor conductor 102a and capacitor conductor 102b are electrically connected to each other. In electrical circuit 32A, capacitor conductors 102a and 102b are connected to ground.

[0082] As shown in Figures 4 and 5, the inductor conductors 41A, 42A, 43A, and 44A are arranged inside the laminate 3. Inductor conductors 42A and 43A have coil axes aligned with the direction perpendicular to the lamination direction. Inductor conductors 42A and 43A have coil axes aligned with the X-axis direction. Inductor conductors 41A and 44A have coil axes aligned with the lamination direction. Inductor conductors 41A and 44A have coil axes aligned with the Z-axis direction.

[0083] In this embodiment, inductor conductors 42A and 43A are single-turn coils. Inductor conductors 41A and 44A are double-turn coils. Each of the inductor conductors 41A, 42A, 43A, and 44A includes, for example, at least one conductor layer 71 and a plurality of connecting conductors 72. Each of the inductor conductors 41A, 42A, 43A, and 44A includes a conductor layer 71 and a plurality of vias 79.

[0084] Each of the pair of external electrodes 85a is connected to, for example, an electrical circuit 21A. For example, one of the pair of external electrodes 85a is connected to a balanced port 11A and, through the balanced port 11A, to a connecting conductor 72 of the end 41a of the inductor conductor 41A. For example, the other of the pair of external electrodes 85a is connected to a balanced port 12A and, through the balanced port 12A, to a connecting conductor 72 of the end 41b of the inductor conductor 41A.

[0085] The pair of external electrodes 85b are connected to electrical circuits 31A and 32A, respectively. One end of the pair of external electrodes 85b is connected to capacitor conductors 101a and 101b. The other end of the pair of external electrodes 85b is connected to capacitor conductors 102a and 102b.

[0086] Each of the pair of external electrodes 85c is connected to an electrical circuit 24A. For example, one of the pair of external electrodes 85c is connected to a balanced port 13A, and through the balanced port 13A is connected to a connecting conductor 72 at the end 43a of the inductor conductor 43A. For example, the other of the pair of external electrodes 85c is connected to a balanced port 14A, and through the balanced port 14A is connected to a connecting conductor 72 at the end 41b of the inductor conductor 44A.

[0087] Next, the effects and advantages of the stacked filters 1 and 1A in this embodiment and its modified form will be explained with reference to Figures 7 to 12.

[0088] In the multilayer filter 1, the input / output section 10 includes an input / output port group consisting of an unbalanced port 11 and a pair of balanced ports 13 and 14. In the multilayer filter 1A, electrical circuits 22 and 23 are magnetically coupled to each other. Electrical circuits 22 and 23 are arranged between electrical circuits 21 and 24 in direction A. Electrical circuits 21, 22, 23, and 24 correspond to resonant circuits. A skip capacitor is connected to the inductor conductor 41 of electrical circuit 21 and the inductor conductor 44 of electrical circuit 24. With this configuration in which electrical circuits 22 and 23 are magnetically coupled, a steep attenuation pole is formed. Furthermore, the skip capacitor forms an even steeper attenuation pole. The multilayer filter 1A includes an input / output section 10A instead of the input / output section 10. The input / output section 10A includes an input / output port group consisting of two pairs of balanced ports 11A, 12A, 13A, and 14A. In this case as well, the stacked filter 1A can achieve the same effects as the stacked filter 1.

[0089] For example, Figures 7 to 12 show various characteristics of the multilayer filter 1. In Figures 7 and 8, data D1 and D3 show the characteristics of the multilayer filter 1 which includes four resonator circuits. Data D2 and D4 show the characteristics of a multilayer filter which includes three resonator circuits. In other words, data D1 and D3 show the characteristics of a four-pole multilayer filter, and data D2 and D4 show the characteristics of a three-pole multilayer filter.

[0090] Data D1 and Data D2 show the relationship between the frequency passing through the stacked filter and the attenuation. As shown in Figure 7, it was confirmed that Data D1 exhibits steeper attenuation compared to Data D2. In other words, it was confirmed that Data D1 is superior to Data D2 in terms of attenuation in the passband around 6000-7000 Hz.

[0091] Data D3 and D4 show the relationship between the frequency through which the signal passes through the stacked filter and the common-mode rejection ratio (CMRR). As shown in Figure 8, it was confirmed that data D3 has a lower CMRR compared to data D4 in the passband of 6000-7000 Hz. In this respect as well, it was confirmed that data D1 is superior to data D2 in terms of attenuation near the passband of 6000-7000 Hz.

[0092] In Figures 9 and 10, data D5 and D7 show the characteristics of the multilayer filter 1 including the first and second skip capacitors. Data D6 and D8 show the characteristics of the multilayer filter without the skip capacitors.

[0093] Data D5 and D6 show the relationship between the frequency passing through the stacked filter and the attenuation. As shown in Figure 9, it was confirmed that data D5 exhibits steeper attenuation compared to data D6. In other words, it was confirmed that data D5 is superior to data D6 in terms of attenuation in the passband around 6000-7000 Hz.

[0094] Data D7 and D8 show the relationship between the frequency through which the signal passes through the stacked filter and the CMRR. As shown in Figure 10, it was confirmed that data D7 has a lower CMRR than data D8 in the passband of 6000-7000 Hz. In this respect as well, it was confirmed that data D7 is superior to data D8 in terms of attenuation near the passband of 6000-7000 Hz.

[0095] In the multilayer filter 1, the capacitor conductor 51c of the first skip capacitor is connected to the end 42a of the inductor conductor 42 of the electrical circuit 21. The capacitor conductor 54c of the first skip capacitor is connected to the end 45a of the inductor conductor 45 of the electrical circuit 24. The capacitor conductor 51f of the second skip capacitor is connected to the end 42b of the inductor conductor 42 of the electrical circuit 21. The capacitor conductor 54f of the second skip capacitor is connected to the end 46a of the inductor conductor 46 of the electrical circuit 24. In this case, an even steeper attenuation pole is formed. In particular, a steeper attenuation pole is formed in the low-frequency range. Balance characteristics can also be improved. The multilayer filter 1A has the same configuration as the multilayer filter 1.

[0096] In Figures 11 and 12, data D9 and D11 show the characteristics of the multilayer filter 1 including the first and second skip capacitors. Data D10 and D12 show the characteristics of a multilayer filter that includes the first skip capacitor but does not include the second skip capacitor.

[0097] Data D9 and D10 show the relationship between the frequency passing through the stacked filter and the attenuation. As shown in Figure 11, it was confirmed that data D9 exhibits steeper attenuation compared to data D10. In other words, it was confirmed that data D9 is superior to data D10 in terms of attenuation in the passband around 6000-7000 Hz.

[0098] Data D11 and D12 show the relationship between the frequency through which the signal passes through the stacked filter and the CMRR. As shown in Figure 11, it was confirmed that data D11 has a lower CMRR compared to data D12 in the passband of 6000-7000 Hz. In this respect as well, it was confirmed that data D11 is superior to data D12 in terms of attenuation near the passband of 6000-7000 Hz.

[0099] In the stacked filter 1, the input / output section 10 includes an input / output port group consisting of an unbalanced port 11 and a pair of balanced ports 13 and 14. The capacitance values ​​of the first skip capacitor, composed of capacitor conductors 51c, 56a, 56b, and 54c, and the capacitance values ​​of the second skip capacitor conductor, composed of capacitor conductors 52c, 55a, 55b, and 53b, are different from each other. In this case, the attenuation pole can be adjusted more reliably.

[0100] In the stacked filter 1A, the input / output section 10A includes an input / output port group consisting of two pairs of balanced ports 11A, 12A, 13A, and 14A. The capacitance values ​​of the first skip capacitor conductor, composed of capacitor conductors 91c, 99a, 99b, and 94c, and the capacitance values ​​of the second skip capacitor conductor, composed of capacitor conductors 91f, 100a, 100b, and 94f, may be equivalent to each other. In this case, the attenuation pole can be adjusted more reliably.

[0101] In the multilayer filter 1, the inductor conductor 44 of the electrical circuit 24 includes inductor conductors 45 and 46 that are electrically connected to each other. Inductor conductor 45 includes ends 45a and 45b. End 45b is connected to inductor conductor 46. Inductor conductor 46 may include ends 46a and 46b. End 46b is connected to end 45b of inductor conductor 45. A pair of balanced ports 13 and 14 included in the input / output section 10 include a balanced port 13 connected to end 45a and a balanced port 14 connected to end 46a. Ends 45b and 46b are connected to an external terminal 15. In this case, for example, a ground terminal or an RF ground terminal may be connected to the external terminal 15. As a result, the attenuation pole can be adjusted more reliably.

[0102] The multilayer filter 1 further comprises capacitor conductors 52c, 55a, 55b, 53b and capacitor conductors 52f, 58a, 58b, 53e that connect the inductor conductor 42 of the electrical circuit 22 and the inductor conductor 43 of the electrical circuit 23. In this case, the attenuation pole can be adjusted more easily. The multilayer filter 1A has a similar configuration.

[0103] In the multilayer filter 1, the inductor conductor 41 includes a conductor layer 71 and a plurality of vias 79. The conductor layer 71 extends in a direction intersecting the stacking direction. The plurality of vias 79 are electrically connected to the conductor layer 71. The plurality of vias 79 are arranged in the stacking direction. With this configuration, the length of the conductive path in the inductor conductor 41 can be ensured in a compact multilayer filter. Multilayer filter 1A has a similar configuration.

[0104] In the multilayer filter 1A, the electrical circuit 21 includes an inductor conductor 41, capacitor conductors 51a, 51b, 51c, and capacitor conductors 51d, 51e, 51f. The inductor conductor 41 has ends 41a and 41b. The capacitor conductors 51a, 51b, and 51c are connected to end 41a. The capacitor conductors 51d, 51e, and 51f are connected to end 41b. In this case, high-frequency spurious emissions can be reduced in the multilayer filter 1A having a balanced-balance characteristic.

[0105] In the stacked filter 1A, electrical circuits 21A and 24A have a mirror-image symmetrical configuration. In this case, variations are suppressed, and a stacked filter with the desired impedance can be realized.

[0106] In the multilayer filter 1A, the coil axes of inductor conductors 41A and 44A intersect with those of inductor conductors 42A and 43A. In this case, magnetic coupling between inductor conductors 41A, 42A and inductor conductors 43A, 44A is suppressed.

[0107] While embodiments and modifications of the present invention have been described above, the present invention is not necessarily limited to the embodiments and modifications described above, and various modifications are possible without departing from the spirit of the invention.

[0108] For example, in the embodiments and modifications described above, the electrical circuits 21 and 24 may be coils wound one or three or more times around a coil axis. The electrical circuits 22 and 23 may be coils wound multiple times or more around a coil axis.

[0109] As can be seen from the descriptions of the embodiments described above, this specification includes disclosures of the following embodiments. (Note 1) A laminate in which multiple dielectric layers are stacked, The laminate comprises a conductive portion provided inside the laminate, The conductor section includes an input / output section, first, second, third, and fourth resonant circuits connected to the input / output section, and a skip capacitor connecting the first resonant circuit and the fourth resonant circuit. The input / output unit includes an input / output port group consisting of an unbalanced port and a pair of balanced ports, or an input / output port group consisting of two pairs of balanced ports. The first, second, third, and fourth resonant circuits each include an inductor conductor having first and second ends, a first capacitor conductor connected to the first end, and a second capacitor conductor connected to the second end. In the first, second, third, and fourth resonant circuits, the second and third resonant circuits are adjacent to each other in a first direction intersecting the stacking direction of the laminate, and are magnetically coupled to each other. It is arranged between the first resonant circuit and the fourth resonant circuit, The first electrode of the skip capacitor is connected to the inductor conductor of the first resonant circuit. A multilayer filter in which the second electrode of the skip capacitor is connected to the inductor conductor of the fourth resonant circuit. (Note 2) The first, second, third, and fourth resonant circuits are arranged in a first direction intersecting the stacking direction of the laminate, The stacked filter according to claim 1, wherein the second and third resonant circuits are arranged between the first resonant circuit and the fourth resonant circuit in the first direction. (Note 3) The aforementioned skip capacitor conductor includes a first skip capacitor conductor and a second skip capacitor conductor. The first electrode of the first skip capacitor conductor is connected to the first end of the first resonant circuit, The second electrode of the first skip capacitor conductor is connected to the first end of the fourth resonant circuit. The first electrode of the second skip capacitor conductor is connected to the second end of the first resonant circuit. The multilayer filter according to Appendix 1 or Appendix 2, wherein the second electrode of the second skip capacitor conductor is connected to the second end of the fourth resonant circuit. (Note 4) The input / output unit includes an input / output port group consisting of the unbalanced port and the pair of balanced ports, The multilayer filter described in Appendix 3, wherein the capacitance value of the first skip capacitor conductor and the capacitance value of the second skip capacitor conductor are different from each other. (Note 5) The input / output unit includes an input / output port group consisting of the two pairs of balanced ports, The multilayer filter described in Appendix 3, wherein the capacitance value of the first skip capacitor conductor and the capacitance value of the second skip capacitor conductor are equivalent to each other. (Note 6) The multilayer filter according to any one of the appendices 1 to 5, further comprising a capacitor conductor connecting the inductor conductor of the second resonant circuit and the inductor conductor of the third resonant circuit. (Note 7) The inductor conductor of the fourth resonant circuit includes first and second inductor conductors that are electrically connected to each other. The first inductor conductor includes the first end and the third end connected to the second inductor conductor. The second inductor conductor includes the second end and a fourth end connected to the third end of the first inductor conductor. The pair of balanced ports included in the input / output unit include a balanced port connected to the first end and a balanced port connected to the second end. The stacked filter described in any one of the appendices 1 to 6, wherein the third end and the fourth end are connected to an external terminal. [Explanation of symbols]

[0110] 1,1A…Multilayer filter, 3…Laminate, 5,5A,6,6A…Conductor part, 15…External terminal, 10,10A…Input / output part, 11…Unbalanced port, 11A,12A,13,13A,14,14A…Balanced port, 41,41A,42,42A,43,43A,44,44A,45,46…Inductor conductor, 51a,51b,51c,51d,51e,51f,52a,52b,52c,52d,52e,52f,53a,53b,53c,53d,53e,53f,54a,54b,54c,54d,54e,54f,55a,5 5b,56a,56b,57a,57b,58a,58b,59a,59b,59c,59d,60a,60b,60c,60d ,91a,91b,91c,91d,91e,91f,92a,92b,92c,92d,92e,92f,93a,93b,9 3c,93d,93e,93f,94a,94b,94c,94d,94e,94f,95a,95b,96a,96b,97a,97b,98a,98b,99a,99b,100a,100b,101a,101b,102a,102b...Capacitor conductor.

Claims

1. A laminate in which multiple dielectric layers are stacked, The laminate comprises a conductive portion provided inside the laminate, The conductor section includes an input / output section, first, second, third, and fourth resonant circuits connected to the input / output section, and a skip capacitor connecting the first resonant circuit and the fourth resonant circuit. The input / output unit includes a group of input / output ports consisting of an unbalanced port and a pair of balanced ports. The first resonant circuit is connected to the unbalanced port, The fourth resonant circuit is connected to the pair of balanced ports, The second and third resonant circuits are arranged between the first resonant circuit and the fourth resonant circuit. The first, second, third, and fourth resonant circuits each include an inductor conductor having first and second ends, a first capacitor conductor connected to the first end, and a second capacitor conductor connected to the second end. In the first, second, third, and fourth resonant circuits, the second and third resonant circuits are adjacent to each other in a first direction intersecting the stacking direction of the laminate, and are magnetically coupled to each other. The first resonant circuit and the second resonant circuit are capacitively coupled to each other. The third resonant circuit and the fourth resonant circuit are capacitively coupled to each other. The first electrode of the skip capacitor is connected to the inductor conductor of the first resonant circuit. A multilayer filter in which the second electrode of the skip capacitor is connected to the inductor conductor of the fourth resonant circuit.

2. The aforementioned skip capacitor includes a first skip capacitor and a second skip capacitor. The first electrode of the first skip capacitor is connected to the first end of the first resonant circuit. The second electrode of the first skip capacitor is connected to the first end of the fourth resonant circuit. The first electrode of the second skip capacitor is connected to the second end of the first resonant circuit. The multilayer filter according to claim 1, wherein the second electrode of the second skip capacitor is connected to the second end of the fourth resonant circuit.

3. The stacked filter according to claim 2, wherein the capacitance value of the first skip capacitor and the capacitance value of the second skip capacitor are different from each other.

4. The multilayer filter according to claim 1, further comprising a capacitor conductor connecting the inductor conductor of the second resonant circuit and the inductor conductor of the third resonant circuit.

5. The inductor conductor of the fourth resonant circuit includes first and second inductor conductors that are electrically connected to each other. The first inductor conductor includes the first end and the third end connected to the second inductor conductor. The second inductor conductor includes the second end and a fourth end connected to the third end of the first inductor conductor. The pair of balanced ports included in the input / output unit include a balanced port connected to the first end and a balanced port connected to the second end. The stacked filter according to claim 1, wherein the third end and the fourth end are connected to an external terminal.

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