JP2010154138A - Layered multiplexer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a layered multiplexer capable of securing an excellent attenuation characteristic in a wide frequency range and downsizing a layered body. <P>SOLUTION: The layered multiplexer (layered diplexer 10) is provided with a plurality of filters 11, 12 which are composed into a layered body layering a plurality of conductive layers are different in passband width. A first filter 11 having the lowest first frequency as a passband width includes a resonator R1 connected to an input side, a resonator R2 connected to a rear stage of the resonator R1, and a resonator R3 connected to a rear stage of the resonator R2. The respective resonators R1, R2, and R3 are composed of via-conductors penetrating the conductive layers in the layer direction and conductive patterns connected to the via-conductors on the conductive layers, and the respective conductive patterns of the resonators R1 and R2 are placed opposite to the layer direction, and are opposite to respective conductive patterns of the resonators R2 and R3 in the layer direction. Thus, the layered multiplexer becomes small and has an excellent attenuation characteristic. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a stacked multiplexer that is mounted on a mobile communication device or the like and includes a plurality of filters each having a different pass band.

In recent years, mobile communication devices are generally configured to be able to share a plurality of different frequency bands. Therefore, a configuration is adopted in which a multiplexer is disposed between the antenna terminal and a high frequency circuit provided for each frequency band, and signals in a plurality of frequency bands are selectively transmitted. Taking a diplexer that selectively transmits signals in two frequency bands as an example, the diplexer can be constituted by, for example, a low-pass filter for a low-frequency band and a high-pass filter for a high-frequency band. However, with this configuration, each signal in the two frequency bands can be separated, but unnecessary components on the low frequency side of the low frequency band and the high frequency side of the high frequency band cannot be removed. For this reason, a technique for configuring a band pass filter corresponding to each frequency band in a diplexer or a multiplexer is known. For example, a distributed-constant band-pass filter (see Patent Document 1) configured with a plurality of resonators using striplines (transmission lines), or a band-pass filter configured by combining a low-pass filter and a high-pass filter (Patent Document 2) See).
Japanese Patent No. 3204753 JP 2007-251107 A

  Among the conventional configurations described above, a bandpass filter configured using a plurality of resonators configures a resonator corresponding to a low frequency band because the resonance frequency of each resonator is determined depending on the length of the stripline. In this case, the stripline becomes long, which leads to an increase in the filter size in the plane direction. In particular, in a multilayer multiplexer corresponding to a plurality of frequency bands, it is necessary to form a plurality of band pass filter circuit elements having different pass bands in a multilayer body, and it is important to suppress the filter size as much as possible. The size limitation due to the resonator using the above becomes a problem. In addition, a band-pass filter configured by combining a low-pass filter and a high-pass filter has a higher degree of design freedom than a distributed-constant band-pass filter, but has a sufficient attenuation in a wide frequency range including a low frequency region. It is difficult to obtain and disadvantageous in terms of characteristics.

  Therefore, the present invention has been made to solve these problems, and is a multilayer multiplexer that can ensure good attenuation characteristics in a wide frequency range and can reduce the size of the multilayer body by suppressing the filter size in the plane direction. The purpose is to provide.

  In order to solve the above-described problem, a multilayer multiplexer according to the present invention is a multilayer multiplexer that is configured as a multilayer body in which a plurality of dielectric layers are stacked and includes a plurality of filters each having a different pass band. A first filter whose pass band is the lowest first frequency band is a first resonator formed of a transmission line connected to an input side of the first filter; A second resonator composed of a transmission line connected to the subsequent stage of the first resonator, and a third resonator composed of a transmission line connected to the subsequent stage of the second resonator. Each of the first to third resonators is a distributed constant type band-pass filter, and each of the first to third resonators includes a via conductor penetrating the dielectric layer in a stacking direction and a conductor pattern connected to the via conductor on the dielectric layer And consists of and before The conductor pattern of the first resonator and the conductor pattern of the second resonator are arranged to face each other in the stacking direction, and the conductor pattern of the second resonator and the conductor of the third resonator Patterns are arranged opposite to each other in the stacking direction.

  According to the multilayer multiplexer of the present invention, the first filter of the multilayer multiplexer has a three-stage configuration including the first to third resonators, and passes the lowest first frequency band to the pass band. It functions as a distributed constant type bandpass filter. Each of these three resonators is composed of a conductor pattern formed in a plurality of dielectric layers and via conductors in the stacking direction connected thereto, and the conductor patterns of adjacent resonators face each other in the stacking direction. Has been placed. Therefore, the size in the plane direction of the resonator can be suppressed by combining the via conductor and the conductor pattern while ensuring the steep attenuation characteristic especially in the vicinity of the passband based on the three-stage attenuation characteristic, and the adjacent resonance The electromagnetic coupling between the units can be appropriately adjusted according to the shape and arrangement of the conductor pattern, and a small-sized and favorable characteristic multilayer multiplexer can be realized.

  In the present invention, the first resonator is connected between a first node and the ground, the second resonator is connected between a second node and the ground, and the third resonator is connected. Is connected between the third node and the ground, and the first filter includes a first capacitor connected between the first node and the ground, the second node and the ground. It is good also as a structure containing the 2nd capacitor | condenser connected between these, and the 3rd capacitor | condenser connected between the said 3rd node and the ground. In this case, the first filter is connected between the first capacitor and the second node, and between the second node and the third node. The fifth capacitor may be configured to include a sixth capacitor connected between the first node and the third node. Further, the first filter includes an inductor connected between an input terminal and the first node, and a parallel resonant circuit connected between the third node and the output terminal. Also good.

  In the present invention, it is preferable that all the plurality of filters are configured using distributed constant type bandpass filters including one or more resonators. In this case, it is preferable that each of the plurality of filters is formed in different regions in the planar direction of the stacked body and arranged so as not to overlap each other in the stacking direction.

  Moreover, you may form the shield conductor part connected to the ground in the said laminated body in the predetermined position which isolate | separates each area | region of these filters. In this case, the shield conductor portion includes a conductor pattern arranged at the predetermined position on each dielectric layer, and a via conductor connected to the conductor pattern and penetrating the dielectric layer in the stacking direction. be able to.

  According to the present invention, a distributed constant type band-pass filter having a three-stage configuration including three resonators is configured for the lowest frequency band, and is connected to a conductor pattern of a plurality of dielectric layers and to it. Each resonator is composed of via conductors in the stacking direction, and a conductive multiplexer pattern between adjacent resonators is arranged opposite to each other in the stacking direction to form a stacked multiplexer. Therefore, it is possible to ensure good attenuation characteristics in a wide frequency range including the vicinity of the passband of the bandpass filter, thereby reliably removing unnecessary components outside the band, and suppressing the filter size in the plane direction of the resonator, thereby reducing the laminate size. It is possible to realize a stacked multiplexer suitable for downsizing.

  Embodiments of the present invention will be described with reference to the drawings. In the following description, the present invention is applied to a multilayer diplexer that selectively transmits signals in two frequency bands and a multilayer triplexer that selectively transmits signals in three passbands as multiplexers mounted on mobile communication devices. The case of applying is described.

[First Embodiment]
In the first embodiment, a case where the present invention is applied to a laminated diplexer will be described. FIG. 1 is a diagram illustrating an equivalent circuit of the multilayer diplexer 10 according to the first embodiment. The multilayer diplexer 10 of the first embodiment includes a distributed constant type band-pass filter 11 (first filter of the present invention) having a first frequency band on the low frequency side as a pass band, and a first frequency band. And a distributed constant type band-pass filter 12 having a higher second frequency band as a pass band. One band pass filter 11 is disposed between the common terminal T0 and the terminal T1, and the other band pass filter 12 is disposed between the common terminal T0 and the terminal T2. The common terminal T0 is a terminal connected to an antenna or the like, the terminal T1 is a terminal connected to the transmission / reception circuit for the first frequency band, and the terminal T2 is connected to the transmission / reception circuit for the second frequency band. Terminal.

  The bandpass filter 11 for the first frequency band includes inductors L10 and L11, capacitors C10, C11, C12, C13, C14, C15, and C16, and three resonators R1 and R2 formed using transmission lines. , R3. In order from the input side, the resonator R1 is connected between the node Na and the ground, the resonator R2 is connected between the node Nb and the ground, and the resonator R3 is connected between the node Nc and the ground. Note that adjacent resonators R1 and R2 are electromagnetically coupled to each other (denoted as M in the drawing) via a conductor pattern described later, and adjacent resonators R2 and R3 are electromagnetically coupled to each other. On the input side, the inductor L10 is connected between the common terminal T0 and the node Na. On the output side, the inductor L11 and the capacitor C16 connected in parallel are connected between the node Nc and the terminal T1. Capacitors C10, C11, and C12 are connected in this order between each of the nodes Na, Nb, and Nc and the ground. Further, a capacitor C13 is connected between the node Na and the node Nb, a capacitor C14 is connected between the node Nb and the node Nc, and a capacitor C15 is connected between the node Na and the node Nc.

  On the other hand, the bandpass filter 12 for the second frequency band includes inductors L20 and L21, capacitors C20, C21, C22, C23 and C24, and two resonators R4 and R5 formed using transmission lines. It consists of The front stage resonator R4 is connected between the node Nd and the ground, and the rear stage resonator R5 is connected between the node Ne and the ground. Adjacent resonators R4 and R5 are electromagnetically coupled to each other. On the input side, the inductor L20 and the capacitor C20 connected in parallel are connected between the common terminal T0 and the node Nd. On the output side, the inductor L21 and the capacitor C24 connected in parallel are connected between the node Ne and the terminal T2. A capacitor C21 is connected between the node Nd and the ground, and a capacitor C22 is connected between the node Ne and the ground. Further, a capacitor C23 is connected between the node Nd and the node Ne.

  As shown in FIG. 1, the bandpass filter 11 for the first frequency band has a three-stage configuration including three resonators R1, R2, and R3, whereas the bandpass filter for the second frequency band. The filter 12 has a two-stage configuration including two resonators R4 and R5. Three resonances corresponding to the resonance frequencies of the resonators R1, R2, and R3 occur in the transmission characteristics of the bandpass filter 11, and the transmission characteristics of the bandpass filter 12 include the resonance frequencies of the resonators R4 and R5. Two corresponding resonances occur. Thus, the configuration of the bandpass filter 11 is suitable for improving the attenuation characteristics on the band side of the first frequency band and ensuring a sufficient attenuation amount over a wide frequency range including the vicinity of the passband. Details will be described later.

  In the configuration of FIG. 1, among the received signals transmitted from the antenna to the common terminal T 0, the received signal in the first frequency band passes through the band-pass filter 11 and is sufficiently attenuated by the band-pass filter 12. It is transmitted to T1. On the other hand, among the above reception signals, the reception signal in the second frequency band is sufficiently attenuated by the bandpass filter 11 while passing through the bandpass filter 12 and transmitted to the terminal T2. Each transmission signal in the first and second frequency bands transmitted from the terminals T1 and T2 via the band-pass filters 11 and 12 through the reverse path is transmitted to the antenna via the common terminal T0. In the transmission characteristics described later of the bandpass filter 11, a transmission direction is assumed in which a reception signal in the first frequency band is input to the common terminal T0 as an input terminal and output to the terminal T1 as an output terminal.

  Next, referring to FIG. 2 to FIG. 5, a structural example using a laminated body in which a plurality of dielectric layers are laminated as one form of the laminated diplexer 10 of the first embodiment will be described. FIG. 2 is an external perspective view of a multilayer body 10a in which the multilayer diplexer 10 according to the first embodiment is configured. A stacked body 10a shown in FIG. 2 has a structure in which a plurality of dielectric layers on which conductor patterns are formed are stacked. A common terminal T0, a first frequency band side terminal T1, a second frequency band side terminal T2, and three ground terminals Tg are formed on the side surface of the laminated body 10a, and each can be externally connected. It has become. Each of these terminals is connected to the conductor pattern on the inner layer of the laminate 10a.

  As shown in FIG. 2, the stacked body 10a is divided into two regions R1 and R2 in the planar direction. The circuit element of the bandpass filter 11 for the first frequency band is formed in the region R1, and the circuit element of the bandpass filter 12 for the second frequency band is formed in the region R2. As a result, the two band-pass filters 11 and 12 are arranged in a region where they do not overlap each other in the stacking direction, ensuring sufficient isolation between them, and as described later, electromagnetic waves between the resonators R1 to R5 in FIG. The arrangement is suitable for securing the coupling.

  3-5 is a top view which shows the structure of each layer of the laminated body 10a. Dielectric layers M1 to M15 using ceramic green sheets are laminated in order from the lower layer inside the laminated body 10a. A large number of conductor patterns and a large number of electrodes as circuit elements are formed on the dielectric layers M1 to M15. The thickness and dielectric constant of each of the dielectric layers M1 to M15 are appropriately set according to necessary electrical characteristics. Each region of each of the dielectric layers M1 to M15 is divided according to FIG. 2, with the right side corresponding to the region R1 of the bandpass filter 11 and the left side of the bandpass filter 12 on the basis of the substantially central position. This corresponds to the region R2.

  Also, a large number of via conductors V (shown by dotted lines in the figure) penetrating in the stacking direction are formed to connect the conductor patterns and electrodes formed in the dielectric layers M1 to M15 to each other. Here, the via conductor V that is a part of each of the resonators R1, R2, and R3 of the bandpass filter 11 is indicated with a symbol in parentheses to distinguish it from the other via conductors V. Each of these via conductors V is formed to extend in the stacking direction via each via hole opened in the dielectric layers M1 to M15. In the following description, the arrangement of the circuit elements of the dielectric layers M1 to M15 is first described, and then the connection relationship in the stacking direction by the via conductor V is described. In each of the dielectric layers M1 to M15, much explanation of the individual via conductors V in each layer is omitted.

  As shown in FIG. 3, a wide ground pattern 15 is formed in the lowermost dielectric layer M1, and its outer edge is connected to the three ground terminals Tg in FIG. Note that a conductor pattern is formed at the position of each terminal in FIG. 2 on the back surface (not shown) of the dielectric layer M1.

  On the dielectric layer M2, an electrode 20 of a capacitor C10, an electrode 21 of a capacitor C11, and an electrode 22 of a capacitor C12 are formed as circuit elements of the bandpass filter 11. These electrodes 20 to 22 are arranged to face the ground pattern 15 in the lower layer. The circuit element of the bandpass filter 12 is not formed on the dielectric layer M2.

  On the dielectric layer M3, as a circuit element of the bandpass filter 11, an electrode 30 common to the capacitors C13 and C15 and an electrode 31 common to the capacitors C14 and C15 are formed. The electrode 32 of the capacitor C21 and the electrode 33 of the capacitor C22 are formed.

  The dielectric layer M4 is provided with an electrode 40 of a capacitor C15 as a circuit element of the bandpass filter 11 and an electrode 41 common to the capacitors C13 and C14, and as a circuit element of the bandpass filter 12, the capacitor C20. Electrode 42 and electrode 43 of capacitor C24 are formed. The electrodes 40 and 41 are disposed opposite to the electrodes 30 and 31 directly below. The electrode 42 is connected to the common terminal T0 on the side surface, and the electrode 43 is connected to the terminal T2 on the side surface.

  In the dielectric layer M5, as a circuit element of the bandpass filter 11, an electrode 50 common to the capacitors C13 and C15 and an electrode 51 common to the capacitors C14, C15, and C16 are formed, and a circuit of the bandpass filter 12 is formed. As elements, an electrode 52 common to the capacitors C20 and C23 and an electrode 53 common to the capacitors C23 and C24 are formed. The electrodes 50 and 51 are disposed opposite to the electrodes 40 and 41 directly below. Further, the electrode 52 is disposed to face the electrode 42 directly below, and the electrode 53 is disposed to face the electrode 43 directly below.

  On the dielectric layer M6, an electrode 60 of a capacitor C16 is formed as a circuit element of the bandpass filter 11, and an electrode 61 of a capacitor C23 is formed as a circuit element of the bandpass filter 12. The electrode 60 is disposed opposite to the electrode 51 directly below, and the electrode 61 is disposed opposite to the electrodes 52 and 53 directly below. The electrode 60 is connected to the terminal T1 on the side surface.

  The dielectric layer M7 is provided with a conductor pattern 70 common to the inductor L10 and the resonator R1 and a conductor pattern 71 of the inductor L11 as circuit elements of the bandpass filter 11, and as a circuit element of the bandpass filter 12. A conductor pattern 72 that is a part of the resonator R4 and a conductor pattern 73 that is a part of the resonator R5 are formed. The conductor pattern 71 is connected to the side terminal T1.

  In the dielectric layer M8, as a circuit element of the band-pass filter 11, a conductor pattern 80 that becomes a part of the inductor L10 and a conductor pattern 81 that becomes a part of the inductor L11 are formed, and the circuit of the band-pass filter 12 As elements, a conductor pattern 82 which is a part of the inductor L20 and a conductor pattern 83 which is a part of the inductor L21 are formed.

  In the dielectric layer M9, as a circuit element of the bandpass filter 11, a conductor pattern 90 that becomes a part of the inductor L10 and a conductor pattern 91 that becomes a part of the resonator R2 are formed. As circuit elements, a conductor pattern 92 that is a part of the inductor L20 and a conductor pattern 93 that is a part of the inductor L21 are formed. The conductor pattern 90 is connected to the side common terminal T0, and the conductor pattern 93 is connected to the side terminal T2.

  In the dielectric layer M10, as circuit elements of the band-pass filter 11, a conductor pattern 100 that is a part of the resonator R1, a conductor pattern 101 that is a part of the resonator R2, and a part of the resonator R3. A conductor pattern 102 is formed, and a conductor pattern 103 that is a part of the inductor L20 is formed as a circuit element of the bandpass filter 12.

  The dielectric layer M11 is provided with a conductor pattern 110 which is a part of the resonator R1 as a circuit element of the bandpass filter 11, and a conductor which is a part of the inductor L20 as a circuit element of the bandpass filter 12. A pattern 111 is formed. The conductor pattern 111 is connected to the common terminal T0 on the side surface.

  In the dielectric layer M12, a conductor pattern 120 that is a part of the resonator R2 is formed as a circuit element of the bandpass filter 11.

  On the dielectric layer M13, as a circuit element of the bandpass filter 11, a conductor pattern 130 that is a part of the resonator R3 and a conductor pattern 131 that is a part of the resonator R2 are formed.

  In the dielectric layer M14, only a plurality of via-hole conductors V that are paths of the circuit elements are formed, and other circuit elements are not formed.

  In the dielectric layer M15, a ground pattern 150 having the same shape as the ground pattern 15 of the dielectric layer M1 is formed, and its outer edge is connected to the three ground terminals Tg in FIG. Note that a dielectric layer (not shown) on which no element is formed is provided on the dielectric layer M15 as a cover of the stacked body 10a.

  Next, the connection relationship in the stacking direction for each circuit element of the dielectric layers M1 to M15 will be described. First, in the band pass filter 11, the inductor L10 on the input side has a structure in which the conductor patterns 70, 80, 90 of the dielectric layers M7, M8, M9 are connected by the via conductor V, respectively. The output-side inductor L11 has a structure in which the conductor patterns 71 and 81 of the dielectric layers M7 and M8 are connected by via conductors V, respectively.

  The resonator R1 connects the via conductor V (1a) extending downward from one end of the conductor pattern 70 of the dielectric layer M7, the other end of the conductor pattern 70, and one end of the conductor pattern 100 of the dielectric layer M10. Via conductor V (1b), via conductor V (1c) connecting the other end of the conductor pattern 100 and one end of the conductor pattern 110 of the dielectric layer M11, and the other end of the conductor pattern 110 and the dielectric layer M15. A via conductor V (1d) connecting the ground pattern 150 is included.

  The resonator R2 connects the via conductor V (2a) extending downward from one end of the conductor pattern 91 of the dielectric layer M9 to the other end of the conductor pattern 91 and one end of the conductor pattern 101 of the dielectric layer M10. Via conductor V (2b), via conductor V (2c) connecting the other end of the conductor pattern 101 and one end of the conductor pattern 120 of the dielectric layer M12, and the other end of the conductor pattern 120 and the dielectric layer M13 A via conductor V (2d) connecting one end of the conductor pattern 131 and a via conductor V (2e) connecting the other end of the conductor pattern 131 and the ground pattern 150 of the dielectric layer M15 are included.

  The resonator R3 connects the via conductor V (3a) extending downward from one end of the conductor pattern 102 of the dielectric layer M10 to the other end of the conductor pattern 102 and one end of the conductor pattern 130 of the dielectric layer M13. The via conductor V (3b) includes a via conductor V (3c) that connects the other end of the conductor pattern 130 and the ground pattern 150 of the dielectric layer M15.

  As described above, each of the resonators R <b> 1 to R <b> 3 is configured by a combination of a via conductor V that penetrates a plurality of dielectric layers in the stacking direction and a substantially L-shaped conductor pattern connected thereto. As shown in FIG. 5, between the two dielectric layers M11 and M12, the conductor pattern 110 of the resonator R1 and the conductor pattern 120 of the resonator R2 are arranged to face each other in the stacking direction. Similarly, between the two dielectric layers M12 and M13, the conductor pattern 120 of the resonator R2 and the conductor pattern 130 of the resonator R3 are arranged to face each other in the stacking direction. In the present embodiment, a desired resonance frequency corresponding to the combination of each via conductor V and the conductor pattern is given to the resonators R1 to R3. On the other hand, since a sufficiently large electromagnetic coupling cannot be obtained only between the via conductors V of the resonators R1 to R3, the shape and size of each conductor pattern arranged close to each other in the stacking direction are appropriately set. By preparing, a structure capable of ensuring sufficient electromagnetic coupling is realized.

  Next, the characteristics of the multilayer diplexer 10 of the first embodiment will be specifically described. FIG. 6 shows the attenuation characteristics of the band-pass filters 11 and 12 obtained by simulation of the multilayer diplexer 10 having the structure of FIGS. In FIG. 6, the characteristic SL1 of the bandpass filter 11 for the first frequency band and the characteristic SH1 of the bandpass filter 12 for the second frequency band are shown superimposed. The characteristic SL1 represents the frequency characteristic of the S parameter S21 (transmission characteristic) from the common terminal T0 to the terminal T1 in the bandpass filter 11, and the characteristic SH1 is the S parameter S21 from the common terminal T0 to the terminal T2 in the bandpass filter 12. The frequency characteristics of (transmission characteristics) are shown. The band pass filter 11 sets a range of approximately 2 to 3 GHz as a pass band, and the band pass filter 12 sets a range of approximately 4.7 to 5.7 GHz as a pass band. The characteristics SL1 and SH1 both have a low loss in the pass band, and the attenuation is large on the low band side and the high band side of the pass band.

  In the multilayer diplexer 10 of the first embodiment, the characteristic SL1 of the low-frequency side band-pass filter 11 has a steep attenuation characteristic in the vicinity of the passband as compared with the high-frequency side band-pass filter 12. As described above, this is because the three-stage configuration of the bandpass filter 11 including the three resonators R1, R2, and R3 and the two-stage configuration of the bandpass filter 12 including the two resonators R4 and R5. Based on the difference with the configuration. In addition, the characteristic SL1 has a wide frequency on the low-pass side and the high-pass side of the pass band as compared with a conventional band-pass filter in which a general low-pass filter and a high-pass filter are connected in series (for example, the configuration of Patent Document 2). A large amount of attenuation can be secured over a range, and unnecessary components from other mobile communication devices can be reliably removed. In general, in order to improve the attenuation characteristics of a bandpass filter, it is necessary to arrange a plurality of resonators having a long transmission line length, and therefore it is unavoidable to increase the filter size in the plane direction. If the structure of the first embodiment as shown in FIG. 5 is adopted, it is possible to realize good attenuation characteristics while keeping the filter size small.

[Second Embodiment]
In the second embodiment, a shield conductor portion is added to the multilayer diplexer 10 of the first embodiment. 7-9 is a top view which shows the structure of each layer of the laminated body 10a which comprised the laminated diplexer 10 of 2nd Embodiment. In the second embodiment, the equivalent circuit shown in FIG. 1 and the external perspective view shown in FIG. 2 are the same as those in the first embodiment, and a description thereof will be omitted.

  As shown in FIGS. 7 to 9, dielectric layers M <b> 1 to M <b> 15 using ceramic green sheets are laminated inside the laminated body 10 a of the second embodiment, as in FIGS. 3 to 5. The circuit elements themselves in each of these dielectric elements M1 to M15 are arranged in the same manner as in the first embodiment. On the other hand, the dielectric layers M1 to M15 of the second embodiment are different from the first embodiment in that five via conductors Vs serving as a shield structure are arranged in parallel near the boundary between the regions R1 and R2 (FIG. 2). It is a point that has been.

  Each via conductor Vs has a lower end connected to the ground pattern 15 of the lowermost dielectric layer M1, extends through the dielectric layers M2 to M15 in sequence, and has an upper end formed as a ground pattern of the dielectric layer M15. 150. Accordingly, a shield conductor portion made of a columnar via conductor Vs is disposed between the region R1 and the region R2 in each of the dielectric layers M1 to M15, and electromagnetic interference between the two bandpass filters 11 and 12 is achieved. There is an effect to suppress.

  In addition, the structure of the shield conductor part shown in 2nd Embodiment is an example, and is not restricted to the structure which arrange | positions the five via conductors Vs. For example, a structure in which only two via conductors Vs at both ends of the five via conductors Vs in FIGS. 7 to 9 are disposed and the two are connected by an elongated reinforcing conductor pattern may be employed.

  Next, the characteristics of the laminated diplexer 10 of the second embodiment will be specifically described. FIG. 10 shows the isolation characteristics obtained by the simulation of the laminated diplexer 10 having the structure of FIGS. In FIG. 10, the isolation characteristic I2 of the multilayer diplexer 10 of the second embodiment is shown by a solid line, and the shield conductor portion is removed from the multilayer diplexer 10 of the second embodiment so as to overlap it (with the first embodiment). The isolation characteristic I1 of the same structure is indicated by a dotted line. 11 and 12 show the attenuation characteristics of the band-pass filters 11 and 12 under the same conditions as in FIG. 6 for the multilayer diplexer 10 having the structure of FIGS. 7 to 9. Also in FIGS. 11 and 12, the characteristics SL2 and SH2 of the bandpass filters 11 and 12 of the second embodiment are indicated by solid lines, respectively, and the characteristics SL1 and SH1 of the structure of the first embodiment are also indicated by dotted lines. .

  As shown in FIG. 10, the isolation characteristic I2 of the second embodiment is improved in a wide frequency range from the low frequency side to the high frequency side compared to the isolation characteristic I1, and the isolation improvement by adopting the shield conductor portion is improved. The effect was confirmed. Further, as shown in FIG. 11, the characteristic SL2 of the bandpass filter 11 of the second embodiment is also improved to some extent on the low frequency side and the high frequency side compared to the characteristic SL1, and this is because the shield conductor This is probably because the ground was strengthened by the department.

[Third Embodiment]
In the third embodiment, a case where the present invention is applied to a stacked triplexer will be described. FIG. 13 is a diagram illustrating an equivalent circuit of the stacked triplexer 200 according to the third embodiment. Of the multilayer triplexer 200 of the third embodiment, the bandpass filter 201 (the first filter of the present invention) whose passband is the first frequency band having the lowest frequency is the bandpass filter 11 of the first embodiment. The band-pass filter 203 having the same circuit configuration as that of the first embodiment and having the third frequency band having the highest frequency as the pass band has the same circuit configuration as the band-pass filter 12 of the first embodiment. Omitted. On the other hand, a band pass filter 202 having a second frequency band between the first frequency band and the third frequency band as a pass band is connected to a common terminal T0 and a terminal TM (a transmission / reception circuit for the second frequency band is connected). Terminal). Note that the terminals TL and TH in FIG. 13 correspond to the terminals T1 and T2 in FIG. 1, respectively.

  The bandpass filter 202 for the second frequency band includes an inductor L30, capacitors C30, C31, C32, C33, and C34, and two resonators R6 and R7 formed using transmission lines. Yes. The configuration of the bandpass filter 202 is different from the bandpass filter 203 in that a capacitor C30 is connected in series between the input-side common terminal T0 and the node Nf. On the other hand, the circuit portion including the resonators R6 and R7, the capacitors C31 to C34, the inductor L30, and the nodes Nf and Ng is configured in the same manner as the bandpass filter 203 (the bandpass filter 12 in FIG. 1). Omitted.

  Next, referring to FIGS. 14 to 17, a structural example using a stacked body in which a plurality of dielectric layers are stacked will be described as an embodiment of the stacked triplexer 200 of the third embodiment. FIG. 14 is an external perspective view of a multilayer body 200a in which the multilayer triplexer 200 according to the third embodiment is configured. The basic structure of the stacked body 200a is the same as that of the stacked body 10a of FIG. 2, but the area sections are different. Further, the terminal arrangements formed on the side surfaces of the laminated body 10a corresponding to the region sections are also different. A common terminal T0 and two ground terminals Tg on both sides are formed on one long side, and a second frequency band side terminal TM and ground terminals Tg on both sides are formed on the other long side. Has been. A terminal TL on the first frequency band side is formed on one short side, and a terminal TH on the third frequency band side is formed on the other short side. Each of these terminals is connected to the conductor pattern on the inner layer of the multilayer body 200a.

  As shown in FIG. 14, the stacked body 200a is divided into three regions RL, RM, and RH in the planar direction corresponding to the three frequency bands. In the region RL, the circuit element of the bandpass filter 201 for the first frequency band is formed, in the region RM, the circuit element of the bandpass filter 202 for the second frequency band is formed, and in the region RH The circuit element of the bandpass filter 203 for the third frequency band is formed. Accordingly, the three band pass filters 201, 202, and 203 are arranged in a region that does not overlap in the stacking direction, and the effect described in the first embodiment can be obtained.

  15-17 is a top view which shows the structure of each layer of the laminated body 200a. The laminated body 200a has a structure in which dielectric layers M1 to M15 in which circuit elements are formed are laminated, similarly to the laminated body 10a of FIGS. Each region of each of the dielectric layers M1 to M15 is divided according to FIG. 14 and corresponds to the region RL of the bandpass filter 201, the region RM of the bandpass filter 202, and the region RH of the bandpass filter 203 in order from the right side. To do. In FIG. 15 to FIG. 17, the circuit elements in the central region RM are shown as different regions RL and RH.

  In the dielectric layers M1 to M15, the circuit elements of the band pass filter 201 are slightly different in position and shape from those in FIGS. 3 to 5 of the first embodiment, reflecting the size of the region RL and the difference in terminal arrangement. The basic connection form is common. That is, the band pass filter 201 of the third embodiment has substantially the same structure as the band pass filter 11 of the first embodiment. Many of the circuit elements of the bandpass filter 203 are common to the connection form of the bandpass filter 12 of the first embodiment. Therefore, the circuit elements of the band-pass filter 201 and the circuit elements common to the first embodiment of the band-pass filter 203 are denoted by the same reference numerals as in FIGS. 3 to 5 and description thereof is omitted. Hereinafter, the circuit elements of the bandpass filter 202 will be described, and then, the circuit elements of the bandpass filter 203 different from the first embodiment will be described.

  First, as a circuit element of the band-pass filter 202, an electrode 35 of a capacitor C31 and an electrode 36 of a capacitor C32 are formed on the dielectric layer M3, and are disposed opposite to the ground pattern 15 of the dielectric layer M1, respectively. An electrode 45 of a capacitor C33 is formed on the dielectric layer M4. The dielectric layer M5 is provided with an electrode 54 of the capacitor C30 and an electrode 55 common to the capacitors C33 and C34. The electrodes 35, 45, 54 are connected via the via conductor V, and the electrodes 36, 55 are connected via the via conductor V.

  An electrode 64 of a capacitor C30 and an electrode 65 of a capacitor C34 are formed on the dielectric layer M6. The electrode 64 is connected to the side common terminal T0, and the electrode 65 is connected to the side terminal TM. Further, as a part of the inductor L30, a conductor pattern 76 of the dielectric layer M7 and a conductor pattern 86 of the dielectric layer M8 are formed.

  One resonator R6 includes conductor patterns 96, 106, 116, and 123 formed in the dielectric layers M9, M10, M11, and M12, respectively, and via conductors V that connect these in the stacking direction. The other resonator R7 includes conductor patterns 97, 107, 117, and 124 formed in the dielectric layers M9, M10, M11, and M12, respectively, and via conductors V that connect them in the stacking direction. Yes. The resonator R6 is connected to the lower electrode 54 and the upper ground pattern 150 via the via conductor V, and the resonator R7 is connected to the lower electrode 55 and the upper ground pattern 150 via the via conductor V.

  Next, among the circuit elements of the bandpass filter 203, those having a connection form different from that of the first embodiment will be described. A ground pattern 23 is formed on the dielectric layer M2, and is connected to the two ground terminals Tg on the side surface. On the dielectric layer M3, the electrode 33 of the capacitor C21 and the electrode 34 of the capacitor C22 are formed, and are disposed to face the ground pattern 23 immediately below. On the dielectric layer M4, the electrode 44 of the capacitor C23 is formed, and is disposed opposite to the electrodes 52 and 53 directly above. On the dielectric layer M6, an electrode 62 of a capacitor C20 and an electrode 63 of a capacitor C24 are formed. The electrode 62 is connected to the side common terminal T0, and the electrode 63 is connected to the side terminal TH. The electrode 62 is disposed opposite to the electrode 52 directly below, and the electrode 63 is disposed opposite to the electrode 53 directly below.

  Regarding the resonators R4 and R5, the number of conductor patterns is increased as the area of the region RH is smaller than that of the first embodiment. That is, one resonator R4 includes conductor patterns 74 and 113 formed in the dielectric layers M7 and M11, respectively, and via conductors V connecting them in the stacking direction. The other resonator R5 is composed of conductor patterns 75 and 114 formed in the dielectric layers M7 and M11, respectively, and via conductors V connecting them in the stacking direction. In the dielectric layer M13, a conductor pattern 133 common to the resonators R4 and R5 is formed.

  As with the inductors L20 and L21, the number of conductor patterns is increased as compared with the first embodiment. That is, conductor patterns 121 and 132 respectively formed on the dielectric layers M12 and M13 are added to the inductor L20, and conductor patterns 105 and 112 respectively formed on the dielectric layers M10, M11, and M12 are added to the inductor L21. , 122 are added. As another circuit element, a ground pattern 141 is added to the dielectric layer M14. The ground pattern 141 is connected to the ground pattern 150 immediately above and the conductor pattern 133 directly below via the via conductor V, respectively.

  The connection form of the band-pass filter 201 is substantially the same as that of the first embodiment, but the conductor pattern 140 is formed on the dielectric layer M14 and is connected to the conductor pattern 102 of the dielectric layer M10 via the via conductor V. Is different.

  Next, the characteristics of the multilayer triplexer 200 of the third embodiment will be specifically described. FIG. 18 shows the attenuation characteristics of the band-pass filters 201, 202, and 203 obtained by simulation of the multilayer diplexer 10 having the structure of FIGS. In FIG. 18, based on the same conditions as in FIG. 6, the characteristic SL3 of the bandpass filter 201 for the first frequency band, the characteristic SM3 of the bandpass filter 202 for the second frequency band, and the third frequency The characteristic SH3 of the band-pass filter 203 for the band is shown superimposed.

  As can be seen from FIG. 18, each of the bandpass filters 201, 202, and 203 has a low loss in the passband, and the attenuation is large on the low band side and the high band side of the pass band. In particular, the characteristic SL3 corresponding to the lowest first frequency band is steep in the vicinity of the pass band, and sufficient attenuation can be obtained in a wide frequency range on the low frequency side. As described above, the same effect as that of the multilayer diplexer 10 according to the first embodiment can be realized with respect to the multilayer triplexer 200 according to the third embodiment.

  The contents of the present invention have been specifically described above based on the present embodiment, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, in the above embodiment, the case where the present invention is applied to a diplexer that selectively transmits signals in two frequency bands and a triplexer that selectively transmits signals in three frequency bands has been described. The present invention can be widely applied to multiplexers that selectively transmit signals in a large number of frequency bands. Assuming N different frequency bands, N filters connected between the common terminal and each of the N terminals are provided, and a filter (this book) having the lowest frequency band among them as a pass band is provided. The first filter of the invention can be configured as shown in the first to third embodiments. This makes it possible to suppress the influence of extraneous unnecessary components caused by mobile communication devices or the like in the multiplexer, particularly in the low frequency region.

It is a figure which shows the equivalent circuit of the laminated diplexer 10 of 1st Embodiment. It is an external appearance perspective view of the laminated body 10a with which the laminated diplexer 10 of 1st Embodiment is comprised. It is a 1st top view showing the structure of each layer of layered product 10a of a 1st embodiment. It is a 2nd top view which shows the structure of each layer of the laminated body 10a of 1st Embodiment. It is a 3rd top view showing the structure of each layer of layered product 10a of a 1st embodiment. It is a figure which shows the attenuation | damping characteristic of the laminated diplexer 10 of 1st Embodiment. It is a 1st top view showing the structure of each layer of layered product 10a of a 2nd embodiment. It is a 2nd top view showing the structure of each layer of layered product 10a of a 2nd embodiment. It is a 3rd top view showing the structure of each layer of layered product 10a of a 2nd embodiment. It is a figure which shows the isolation characteristic of the laminated diplexer 10 of 2nd Embodiment. It is a figure which shows the attenuation | damping characteristic of the band pass filter 11 among the multilayer diplexers 10 of 2nd Embodiment. It is a figure which shows the attenuation | damping characteristic of the band pass filter 12 among the multilayer diplexers 10 of 2nd Embodiment. It is a figure which shows the equivalent circuit of the laminated | stacked triplexer 200 of 3rd Embodiment. It is an external appearance perspective view of the laminated body 200a with which the laminated triplexer 200 of 3rd Embodiment is comprised. It is a 1st top view showing the structure of each layer of layered product 200a of a 3rd embodiment. It is the 2nd top view showing the structure of each layer of layered product 200a of a 3rd embodiment. It is a 3rd top view showing the structure of each layer of layered product 200a of a 3rd embodiment. It is a figure which shows the attenuation | damping characteristic of the lamination type triplexer 200 of 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Laminated diplexer 200 ... Laminated triplexer 10a, 200a ... Laminated body 11, 12, 201, 202, 203 ... Band pass filter 15, 23, 141, 150 ... Ground pattern 20-22, 30-36, 40-45 , 50 to 55, 60 to 65 ... electrodes 70 to 76, 80 to 86, 90 to 97, 100 to 107, 110 to 114, 116, 117, 120 to 124, 130 to 133, 140 ... conductor patterns C10 to C16, C20-C24, C30-C34: Capacitors L10, L11, L20, L21, L30 ... Inductors R1-R7 ... Resonator T0 ... Common terminals T1, T2, TL, TM, TH ... Terminal Tg ... Ground terminals M1-M15 ... Dielectric Body layer V ... via conductor

Claims (8)

A multilayer multiplexer comprising a plurality of dielectric layers and a plurality of filters each having a different passband,
Of the plurality of filters, the first filter having the lowest first frequency band as the pass band is:
A first resonator composed of a transmission line connected to the input side of the first filter;
A second resonator composed of a transmission line connected to a subsequent stage of the first resonator;
A third resonator composed of a transmission line connected to a subsequent stage of the second resonator;
Each of the first to third resonators is connected to the via conductor passing through the dielectric layer in the stacking direction and the via conductor on the dielectric layer. And the conductor pattern of the first resonator and the conductor pattern of the second resonator are arranged to face each other in the stacking direction, and the conductor pattern of the second resonator and the conductor pattern of the second resonator A stacked multiplexer, wherein the conductor pattern of the third resonator is arranged opposite to the stacking direction. The first resonator is connected between a first node and ground, the second resonator is connected between a second node and ground, and the third resonator is a third node. Connected between the node and ground,
The first filter includes a first capacitor connected between the first node and ground, a second capacitor connected between the second node and ground, and the third filter. The multilayer multiplexer according to claim 1, further comprising: a third capacitor connected between the node and the ground.   The first filter includes a fourth capacitor connected between the first node and the second node, and a second capacitor connected between the second node and the third node. The multilayer multiplexer according to claim 2, further comprising: a fifth capacitor, and a sixth capacitor connected between the first node and the third node.   The first filter includes an inductor connected between an input terminal and the first node, and a parallel resonant circuit connected between the third node and an output terminal. The stacked multiplexer according to claim 3.   2. The multilayer multiplexer according to claim 1, wherein all the plurality of filters are distributed constant type band-pass filters including one or a plurality of resonators.   6. The multilayer multiplexer according to claim 5, wherein each of the plurality of filters is formed in different regions in the planar direction of the multilayer body and is arranged so as not to overlap each other in the lamination direction.   7. The multilayer multiplexer according to claim 6, wherein a shield conductor portion connected to a ground is formed in the multilayer body at a predetermined position separating each region of the plurality of filters. The shield conductor portion is composed of a conductor pattern arranged at the predetermined position on each dielectric layer and a via conductor connected to the conductor pattern and penetrating the dielectric layer in the stacking direction. The stacked multiplexer according to claim 7.

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