阅读说明：本技术 多路复用器、高频模块以及通信装置 (Multiplexer, high-frequency module, and communication device ) 是由 五十岚一浩 永森启之 于 2020-03-11 设计创作，主要内容包括：本发明提供多路复用器、高频模块以及通信装置。在使第一通信频带的第一通信信号通过的第一滤波器中,进行第二通信频带以及第三通信频带上的衰减。多路复用器(1)具备第一滤波器(第一发送滤波器(31))、第二滤波器(第二接收滤波器(42))、第三滤波器(第三接收滤波器(43))、第一电感器(51)、以及第二电感器(52)。第一电感器(51)在第一滤波器的一个并联臂谐振器(第二并联臂谐振器)与接地之间,与一个并联臂谐振器串联连接。第二电感器(52)在第一滤波器的另一个并联臂谐振器(第三并联臂谐振器)与接地之间,与另一个并联臂谐振器串联连接。第一电感器(51)和第二电感器(52)的从第一滤波器侧向接地侧的卷绕方向大致相同。(The invention provides a multiplexer, a high-frequency module and a communication device. The first filter for passing the first communication signal of the first communication band performs attenuation in the second communication band and the third communication band. A multiplexer (1) is provided with a first filter (first transmission filter (31)), a second filter (second reception filter (42)), a third filter (third reception filter (43)), a first inductor (51), and a second inductor (52). The first inductor (51) is connected in series with one parallel arm resonator of the first filter between the one parallel arm resonator (second parallel arm resonator) and the ground. The second inductor (52) is connected in series with the other parallel arm resonator of the first filter between the other parallel arm resonator (third parallel arm resonator) and the ground. The winding directions of the first inductor (51) and the second inductor (52) from the first filter side to the ground side are substantially the same.)

1. A multiplexer is provided with:

a common terminal;

a first filter which is electrically connectable to the common terminal and which passes a first communication signal of a first communication frequency band, and which is a ladder filter including a plurality of parallel arm resonators;

a second filter that is electrically connectable to the common terminal and that passes a second communication signal in a second communication frequency band lower than the first communication frequency band;

a third filter that is electrically connectable to the common terminal and that passes a third communication signal in a third communication frequency band lower than the second communication frequency band;

a first inductor connected in series to one of the plurality of parallel arm resonators of the first filter between the one parallel arm resonator and a ground; and

a second inductor connected in series with the other parallel arm resonator among the plurality of parallel arm resonators of the first filter between the other parallel arm resonator and a ground,

the winding directions of the first inductor and the second inductor from the first filter side to the ground side are substantially the same.

2. The multiplexer of claim 1,

the plurality of parallel arm resonators include:

a first parallel arm resonator having a first resonance frequency lower than the first communication band;

a second parallel arm resonator which is the one parallel arm resonator and has a second resonance frequency lower than the first resonance frequency and included in the second communication band; and

the third parallel arm resonator is a parallel arm resonator which is the other parallel arm resonator, and has a third resonance frequency included in the third communication band.

3. The multiplexer of claim 1 or 2,

the first inductor and the second inductor face each other at a portion closest to each other, and the facing portions are substantially parallel to each other.

4. The multiplexer of claim 3,

further comprises a substrate provided with the first inductor and the second inductor,

the facing portions of the first inductor and the second inductor are provided in different layers of the substrate.

5. The multiplexer of claim 2,

further comprising a third inductor connected to the first filter,

the plurality of parallel arm resonators further includes a fourth parallel arm resonator having a fourth resonance frequency,

the third inductor is connected in series with the fourth parallel arm resonator between the fourth parallel arm resonator of the first filter and the ground,

the third inductor is wound in substantially the same direction as the first inductor and the second inductor from the first filter side to the ground side.

6. A multiplexer according to any one of claims 1 to 5,

the above-mentioned first communication signal is a transmission signal of a communication Band of Band1,

the above-mentioned second communication signal is a reception signal of the communication Band of Band3,

the third communication signal is a reception signal in the communication Band of Band 32.

7. A high-frequency module is provided with:

a multiplexer as claimed in any one of claims 1 to 6;

a first amplifier connected to the first filter;

a second amplifier connected to the second filter; and

and a third amplifier connected to the third filter.

8. A communication device is provided with:

the high frequency module of claim 7; and

and a signal processing circuit that processes the first communication signal, the second communication signal, and the third communication signal.

Technical Field

The present invention generally relates to a multiplexer, a high frequency module, and a communication apparatus. More specifically, the present invention relates to a multiplexer that can be used while supporting a plurality of different communications, a high-frequency module including the multiplexer, and a communication device including the high-frequency module.

Background

Conventionally, a multiplexer that can be used simultaneously in response to a plurality of communications different from each other is known (for example, see patent document 1).

In the multiplexer described in patent document 1, transmission of Band1 and reception of Band3 are simultaneously performed or transmission of Band1 and reception of Band32 are simultaneously performed by Carrier Aggregation (CA) for simultaneously transmitting and receiving signals of a plurality of frequency bands. The multiplexer described in patent document 1 bundles a plurality of carriers or channels.

Patent document 1: japanese laid-open patent publication No. 2015-201808

However, in the conventional multiplexer described in patent document 1, attenuation in the reception Band of the Band3 (second communication Band) may be insufficient in the transmission filter (first filter) of the Band1 (first communication Band). Similarly, in the transmission filter of Band1, attenuation in the reception Band of Band32 (third communication Band) may be insufficient.

Disclosure of Invention

The present invention has been made in view of the above-described points, and an object of the present invention is to provide a multiplexer, a high-frequency module, and a communication device capable of performing attenuation in a second communication band and a third communication band in a first filter that passes a first communication signal in a first communication band.

A multiplexer according to an aspect of the present invention includes a common terminal, a first filter, a second filter, a third filter, a first inductor, and a second inductor. The first filter is electrically connectable to the common terminal and is a filter that allows a first communication signal in a first communication frequency band to pass therethrough. The first filter is a ladder filter including a plurality of parallel arm resonators. The second filter is electrically connected to the common terminal and is configured to pass a second communication signal in a second communication frequency band lower than the first communication frequency band. The third filter is electrically connected to the common terminal and is configured to pass a third communication signal having a third communication frequency band lower than the second communication frequency band. The first inductor is connected in series with one of the plurality of parallel arm resonators of the first filter between the one parallel arm resonator and a ground. The second inductor is connected in series with the other parallel arm resonator among the plurality of parallel arm resonators of the first filter between the other parallel arm resonator and a ground. The winding directions of the first inductor and the second inductor from the first filter side to the ground side are substantially the same.

A high-frequency module according to an aspect of the present invention includes the multiplexer, the first amplifier, the second amplifier, and the third amplifier. The first amplifier is connected to the first filter. The second amplifier is connected to the second filter. The third amplifier is connected to the third filter.

A communication device according to an aspect of the present invention includes the high-frequency module and a signal processing circuit. The signal processing circuit processes the first communication signal, the second communication signal, and the third communication signal.

According to the multiplexer, the high-frequency module, and the communication device according to the above-described aspect of the present invention, the attenuation in the second communication band and the third communication band can be performed in the first filter that passes the first communication signal in the first communication band.

Drawings

Fig. 1 is a plan view of a multiplexer according to an embodiment.

Fig. 2 is a plan view of a main part of the multiplexer.

Fig. 3 is a schematic configuration diagram of the multiplexer described above.

Fig. 4 is a circuit diagram of a transmission filter in the multiplexer described above.

Fig. 5 is a graph showing the filter characteristics of the transmission filter in the multiplexer.

Fig. 6 is a schematic configuration diagram of a communication device according to the embodiment.

Fig. 7 is a plan view of a multiplexer according to a modification of the embodiment.

Fig. 8 is a plan view of a main portion of the multiplexer.

Fig. 9 is a graph showing the filter characteristics of the transmission filter in the multiplexer.

Description of the reference numerals

1 … multiplexer; 10 … a substrate; 101 … major face; 11 … a first terminal; 12 … a second terminal; 13 … a third terminal; 14 … fourth terminal; 15 … fifth terminal; 2 … common terminal; 31 … a first transmission filter (first filter, second filter); 32 … second transmit filter (third filter); 41 … a first receiving filter (first filter); 42 … second receive filter (second filter); 43 … third receive filter (third filter); 51 … a first inductor; 511-513 … conductor portions; 514 … opposite portions; 52 … second inductor; 521 ~ 523 … conductor part; 524. 525 … opposite portions; 53 … third inductor; 531 to 533 … conductor portions; 534 … opposite portions; 61 … first series arm resonator; 62 … second series arm resonator; 63 … third series arm resonator; 64 … fourth series arm resonator; 65 … fifth series arm resonator; 66 … first parallel arm resonator; 67 … second parallel arm resonator; 68 … third parallel arm resonator; 69 … fourth parallel arm resonator; 7 … high frequency module; 71 … power amplifier (first amplifier); 72 … power amplifier; 73 … LNA; a74 … LNA (second amplifier); 75 … LNA (third amplifier); 8 … a communication device; 81 … baseband signal processing circuit (signal processing circuit); 82 … RF signal processing circuitry (signal processing circuitry); 9 … antenna; t1 … first transmission path; t2 … second transmit path; r1 … first receive path; r2 … second receive path; r3 … third receive path; a P1 … first terminal; a P2 … second terminal; a P3 … third terminal; a P4 … fourth terminal; a P5 … fifth terminal; a P6 … sixth terminal; an N1 … first node; a second node of N2 …; a third node of N3 …; n4 … fourth node; the S1 … path; s21 … first path; s22 … second path; s23 … third path; s24 … fourth path; g1 … first ground terminal; g2 … second ground terminal; g3 … third ground terminal; a1 … characteristic; a2 … characteristic; a3 … characteristic; f1 … a first frequency; f2 … a second frequency; f3 … third frequency; f4 … fourth frequency; a first direction D1 …; d2 … second direction.

Detailed Description

Hereinafter, a multiplexer, a high-frequency module, and a communication device according to an embodiment will be described with reference to the drawings. The drawings referred to in the following embodiments and the like are schematic drawings, and the ratio of the size and thickness of each component in the drawings does not necessarily reflect the actual dimensional ratio.

(embodiment mode)

(1) Multiplexer

The overall configuration of the multiplexer 1 according to the embodiment will be described with reference to the drawings.

As shown in fig. 3, the multiplexer 1 according to the present embodiment includes a common terminal 2, a first transmission filter 31 (first filter), a second transmission filter 32, a first reception filter 41, a second reception filter 42 (second filter), and a third reception filter 43 (third filter). The multiplexer 1 includes a first terminal 11, a second terminal 12, a third terminal 13, a fourth terminal 14, and a fifth terminal 15. As shown in fig. 4, the multiplexer 1 further includes a first inductor 51, a second inductor 52, and a third inductor 53.

In the present embodiment, the multiplexer 1 handles simultaneous use of transmission of the first communication band and reception of the second communication band, and simultaneous use of transmission of the first communication band and reception of the third communication band. The multiplexer 1 performs a case of carrier aggregation in which a plurality of signals are simultaneously communicated. More specifically, the multiplexer 1 according to the present embodiment can perform carrier aggregation of the transmission signal of the first communication band and the reception signal of the second communication band, and carrier aggregation of the transmission signal of the first communication band and the reception signal of the third communication band. The multiplexer 1 is not limited to performing carrier aggregation.

The multiplexer 1 is for example used in a mobile phone like a smartphone. The multiplexer 1 is not limited to a mobile phone, and may be a wearable terminal such as a smart watch, for example. In summary, as shown in fig. 6, the multiplexer 1 is used for a communication device 8 that communicates with an external device (not shown).

(2) Each component of the multiplexer

Hereinafter, each constituent element of the multiplexer 1 according to the present embodiment will be described with reference to the drawings.

(2.1) common terminal

The common terminal 2 shown in fig. 3 is electrically connected to the antenna 9 (see fig. 6). The common terminal 2 is not limited to being directly connected to the antenna 9, and may be indirectly connected to the antenna 9. In other words, a circuit or a circuit element such as a matching circuit may be inserted between the common terminal 2 and the antenna 9.

(2.2) first transmitting Filter, first receiving Filter

As shown in fig. 3, the first transmission filter 31 is provided on a first transmission path T1 for transmitting a first transmission signal to the antenna 9 (see fig. 6). The first transmission path T1 is a path for transmitting a first transmission signal via the common terminal 2. The first transmission filter 31 passes a first transmission signal of a first communication band (first band). The first communication Band is, for example, Band1 (transmission Band: 1920 MHz-1980 MHz) of the LTE (Long Term Evolution: Long Term Evolution) standard (including the LTE-Advanced standard).

As described above, the first transmission filter 31 is a first filter that is provided on the first transmission path (the first transmission path T1) for transmitting the first communication signal (the first transmission signal) of the first communication frequency band via the common terminal 2 and that passes the first communication signal. The first communication signal is a transmission signal of a communication Band of Band 1.

As shown in fig. 3, the first reception filter 41 is provided in a first reception path R1 for receiving a first reception signal from the antenna 9 (see fig. 6). In other words, the first reception path R1 is a path for receiving the first reception signal via the common terminal 2. The first reception filter 41 passes a first reception signal of a first communication band (first band). The first communication band of the first reception signal is different from the first communication band of the first transmission signal. The first communication Band is, for example, Band1 (reception Band: 2110 MHz-2170 MHz) of the LTE (long termevision) standard (including the LTE-Advanced standard).

(2.3) second transmitting Filter and second receiving Filter

As shown in fig. 3, second transmission filter 32 is provided in second transmission path T2 for transmitting the second transmission signal to antenna 9 (see fig. 6). The second transmission path T2 is a path for transmitting a second transmission signal via the common terminal 2. The second transmission filter 32 passes a second transmission signal of a second communication band (second band). The second communication Band is, for example, Band3 (transmission Band: 1710 MHz-1785 MHz) of the LTE (long Term evolution) standard (including the LTE-Advanced standard).

As shown in fig. 3, the second reception filter 42 is provided in a second reception path R2 for receiving a second reception signal from the antenna 9 (see fig. 6). In other words, the second reception path R2 is a path for receiving the second reception signal via the common terminal 2. The second reception filter 42 passes the second reception signal of the second communication band (second band). The second communication band of the second reception signal is different from the second communication band of the second transmission signal. The second communication Band is, for example, Band3 (reception Band: 1805 MHz-1880 MHz) of the LTE (long termevision) standard (including the LTE-Advanced standard).

As described above, the second reception filter 42 is a second filter that is provided in the second transmission path (second reception path R2) for transmitting the second communication signal (second reception signal) in the second communication frequency band lower than the first communication frequency band via the common terminal 2 and passes the second communication signal. The second communication signal is a reception signal of the communication Band of Band 3. The upper limit frequency of the first communication band is lower than the lower limit frequency of the first communication band.

(2.4) third receiving Filter

As shown in fig. 3, the third reception filter 43 is provided in a third reception path R3 for receiving a third reception signal from the antenna 9 (see fig. 6). The third reception path R3 is a path for transmitting a third reception signal via the common terminal 2. The third reception filter 43 passes the third reception signal of the third communication band (third band). The third communication Band is, for example, Band32 (reception Band: 1452MHz to 1496MHz) of the LTE standard (including the LTE-Advanced standard).

As described above, the third reception filter 43 is a third filter that is provided in the third transmission path (third reception path R3) for transmitting the third communication signal (third reception signal) in the third communication frequency band lower than the second communication frequency band via the common terminal 2 and passes the third communication signal. The third communication signal is a reception signal of a communication Band of Band 32. The upper limit frequency of the third communication band is lower than the lower limit frequency of the second communication band.

(2.5) first to fifth terminals

As shown in fig. 3, the first terminal 11 is provided on the first transmission path T1 and electrically connected to the first transmission filter 31. The first terminal 11 is electrically connected to a power amplifier 71 (see fig. 6) described later. The second terminal 12 is provided on the second transmission path T2 and electrically connected to the second transmission filter 32. The second terminal 12 is electrically connected to a power amplifier 72 (see fig. 6) described later. The third terminal 13 is provided on the first reception path R1 and electrically connected to the first reception filter 41. The third terminal 13 is electrically connected to an LNA (Low Noise Amplifier)73 (see fig. 6) described later. The fourth terminal 14 is provided on the second reception path R2 and electrically connected to the second reception filter 42. The fourth terminal 14 is electrically connected to an LNA74 (see fig. 6) described later. The fifth terminal 15 is provided on the third receiving path R3 and electrically connected to the third receiving filter 43. The fifth terminal 15 is electrically connected to an LNA75 (see fig. 6) described later.

(2.6) detailed Structure of first Transmission Filter

As shown in fig. 4, the first transmission filter 31 (first filter) is a ladder filter. The first transmission filter 31 is provided with a plurality of (5 in the illustrated example) series arm resonators and a plurality of (4 in the illustrated example) parallel arm resonators. In addition, the first transmission filter 31 has a first terminal P1, a second terminal P2, a third terminal P3, a fourth terminal P4, a fifth terminal P5, and a sixth terminal P6.

As shown in fig. 4, the plurality of series-arm resonators include a first series-arm resonator 61, a second series-arm resonator 62, a third series-arm resonator 63, a fourth series-arm resonator 64, and a fifth series-arm resonator 65. A plurality of series-arm resonators are disposed on the path S1 between the fifth terminal P5 and the sixth terminal P6. The plurality of series-arm resonators are connected in series on the path S1. A plurality of series arm resonators are arranged in the order of the first series arm resonator 61, the second series arm resonator 62, the third series arm resonator 63, the fourth series arm resonator 64, and the fifth series arm resonator 65 from the common terminal 2 side.

As shown in fig. 4, the plurality of parallel arm resonators include a first parallel arm resonator 66, a second parallel arm resonator 67, a third parallel arm resonator 68, and a fourth parallel arm resonator 69.

The first parallel-arm resonator 66 has a first resonant frequency. The first resonance frequency is lower than the first communication band. More specifically, the first resonance frequency is lower than the lower limit frequency of the first communication band. The first parallel-arm resonator 66 is disposed between the path S1 and the ground. In more detail, the first parallel-arm resonator 66 is disposed on a first path S21 between the first node N1 and the first terminal P1 on the path S1. The first node N1 is located between the third series-arm resonator 63 and the fourth series-arm resonator 64 on the path S1. The first terminal P1 is electrically connected to ground. In other words, the potential of the first terminal P1 is the ground potential.

The second parallel-arm resonator 67 has a second resonance frequency. The second resonance frequency is lower than the first resonance frequency and is included in the second communication band. The second parallel arm resonator 67 is disposed between the path S1 and the ground. In more detail, the second parallel-arm resonator 67 is disposed on the second path S22 between the second node N2 and the second terminal P2 on the path S1. The second node N2 is located between the first series-arm resonator 61 and the second series-arm resonator 62 on the path S1.

The third parallel-arm resonator 68 has a third resonance frequency. The third resonance frequency is included in the third communication band. The third parallel arm resonator 68 is disposed between the path S1 and the ground. In more detail, the third parallel-arm resonator 68 is disposed on the third path S23 between the third node N3 and the third terminal P3 on the path S1. The third node N3 is located between the second series-arm resonator 62 and the third series-arm resonator 63 on the path S1.

The fourth parallel-arm resonator 69 has a fourth resonance frequency. The fourth parallel arm resonator 69 is provided between the path S1 and the ground. In more detail, the fourth parallel-arm resonator 69 is disposed on the fourth path S24 between the fourth node N4 and the fourth terminal P4 on the path S1. The fourth node N4 is located between the fourth series-arm resonator 64 and the fifth series-arm resonator 65 on the path S1.

(2.7) first to third inductors

As shown in fig. 4, the first inductor 51 is connected to the first transmission filter 31 (first filter). More specifically, the first inductor 51 is connected in series to the second parallel arm resonator 67 of the first transmission filter 31 between the second parallel arm resonator 67 and the ground.

The second inductor 52 is connected to the first transmission filter 31 (first filter). More specifically, the second inductor 52 is connected in series to the third parallel arm resonator 68 of the first transmission filter 31 between the third parallel arm resonator 68 and the ground.

The third inductor 53 is connected to the first transmission filter 31 (first filter). More specifically, the third inductor 53 is connected in series to the fourth parallel arm resonator 69 between the fourth parallel arm resonator 69 of the first transmission filter 31 and the ground.

Here, as shown in fig. 1, the multiplexer 1 further includes a substrate 10. A first inductor 51, a second inductor 52, and a third inductor 53 are provided on the substrate 10. In the example of fig. 1, the first inductor 51, the second inductor 52, and the third inductor 53 are provided on the main surface 101 of the substrate 10. Further, on the main surface 101 of the substrate 10, the first transmission filter 31, the second transmission filter 32, the first reception filter 41, the second reception filter 42, and the third reception filter 43 are arranged.

As shown in fig. 2, the first inductor 51 is provided on the main surface 101 of the substrate 10. One end of the first inductor 51 is connected to the second terminal P2. On the other hand, the other end of the first inductor 51 is connected to the first ground terminal G1. The first ground terminal G1 is connected to ground either directly or indirectly.

The first inductor 51 has a plurality of (3 in the example of the figure) conductor portions 511-513. The conductor portion 511 is disposed along the first direction D1, and is connected to the second terminal P2. The conductor portion 512 is disposed along the second direction D2 and is connected to the conductor portion 511. The conductor portion 513 is disposed along the first direction D1, and is connected to the conductor portion 512 and the first ground terminal G1. The plurality of conductor portions 511-513 are integrally provided. Further, the first inductor 51 is provided integrally with the second terminal P2 and the first ground terminal G1.

The first inductor 51 is provided around an axis along the normal direction of the main surface 101 of the substrate 10. The first inductor 51 may be wound for at least 1 cycle, or may be unwound for 1 cycle. The first inductor 51 may be provided not only on the main surface 101 of the substrate 10 but also on the inner surface of the main surface 101 and the substrate 10.

As shown in fig. 2, the second inductor 52 is provided on the main surface 101 of the substrate 10. One end of the second inductor 52 is connected to the third terminal P3. On the other hand, the other end of the second inductor 52 is connected to a second ground terminal G2. The second ground terminal G2 is connected to ground either directly or indirectly.

The second inductor 52 has a plurality of (3 in the example of the figure) conductor sections 521 ~ 523. The conductor portion 521 is disposed along the second direction D2 and is connected to the third terminal P3. The conductor portion 522 is disposed along the first direction D1 and connected to the conductor portion 521. The conductor portion 523 is disposed along the second direction D2, and is connected to the conductor portion 522 and the second ground terminal G2. The plurality of conductor sections 521-523 are provided integrally. Further, the second inductor 52 is integrally provided with the third terminal P3 and the second ground terminal G2.

The second inductor 52 is provided around an axis along the normal direction of the main surface 101 of the substrate 10. The second inductor 52 may be wound for at least 1 cycle, or may be unwound for 1 cycle. The second inductor 52 may be provided not only on the main surface 101 of the substrate 10 but also on the inner surface of the main surface 101 and the substrate 10.

As shown in fig. 2, the third inductor 53 is provided on the main surface 101 of the substrate 10. One end of the third inductor 53 is connected to a fourth terminal P4. On the other hand, the other end of the third inductor 53 is connected to a third ground terminal G3. The third ground terminal G3 is connected to ground either directly or indirectly.

The third inductor 53 has a plurality of (3 in the example of the figure) conductor portions 531 to 533. The conductor portion 531 is disposed along the first direction D1 and is connected to the fourth terminal P4. The conductor portion 532 is disposed along the second direction D2 and connected to the conductor portion 531. The conductor portion 533 is disposed along the first direction D1, and is connected to the conductor portion 532 and the third ground terminal G3. The plurality of conductor portions 531 to 533 are provided integrally. Further, the third inductor 53 is provided integrally with the fourth terminal P4 and the third ground terminal G3.

The third inductor 53 is provided around an axis along the normal direction of the main surface 101 of the substrate 10. The third inductor 53 may be wound for at least 1 cycle, or may be unwound for 1 cycle. The third inductor 53 may be provided not only on the main surface 101 of the substrate 10 but also on the inner surface of the main surface 101 and the substrate 10.

As shown in fig. 2, the winding directions of the first inductor 51 and the second inductor 52 from the first transmission filter 31 (first filter) side to the ground side are the same. In more detail, the winding direction from the second terminal P2 side to the first ground terminal G1 side in the first inductor 51 is the same as the winding direction from the third terminal P3 side to the second ground terminal G2 side in the second inductor 52. In fig. 2, the winding direction of the first inductor 51 and the winding direction of the second inductor 52 are both counterclockwise.

According to the above, even in the case where the first transmission signal (first communication signal) and the first reception signal (second communication signal) are simultaneously transmitted and the first transmission signal (first communication signal) and the second reception signal (third communication signal) are simultaneously transmitted, attenuation in Band3 (second communication Band) and Band32 (third communication Band) can be performed in the first transmission filter 31 (first filter) through which the first transmission signal (first communication signal) in Band1 (first communication Band) passes.

As shown in fig. 2, the third inductor 53 is wound in the same direction as the first inductor 51 and the second inductor 52 from the first transmission filter 31 (first filter) side to the ground side. In more detail, the winding direction from the fourth terminal P4 side to the third ground terminal G3 side in the third inductor 53 is the same as the winding direction from the second terminal P2 side to the first ground terminal G1 side in the first inductor 51 and the winding direction from the third terminal P3 side to the second ground terminal G2 side in the second inductor 52. In fig. 2, the winding direction of the third inductor 53 is the same as the winding direction of the first inductor 51 and the winding direction of the second inductor 52, and is counterclockwise.

However, as shown in fig. 2, the first inductor 51 and the second inductor 52 are opposed to each other at a portion closest to each other. In the first inductor 51 and the second inductor 52, the "portions closest to each other" mean the portions closest to each other in three dimensions. In addition, as in the example of fig. 2, when the first inductor 51 and the second inductor 52 are located on the same plane, the portions closest to each other are portions closest to each other on the plane.

The phrase "facing each other at the closest portion" means that the facing surfaces face each other in a state where the closest portions are close to each other. The phrase "opposed to portions closest to each other" means that there is no conductor different from the first inductor 51 and the second inductor between the portions, and the portions are opposed to each other.

Further, the opposing portions of the first inductor 51 and the second inductor 52 are substantially parallel to each other. In more detail, the opposing portion 514 of the first inductor 51 to the second inductor 52 and the opposing portion 524 of the second inductor 52 to the first inductor 51 are substantially parallel. Here, "the facing portion 514 is substantially parallel to the facing portion 524" includes a case where the facing portion 514 is completely parallel to the facing portion 524, and a case where an angle formed by the facing portion 514 and the facing portion 524 is 10 degrees or less. The "angle formed by the opposing portion 514 and the opposing portion 524" refers to an angle formed by a line segment along the longitudinal direction of the opposing portion 514 and a line segment along the longitudinal direction of the opposing portion 524. The "longitudinal direction of the facing portion 514" is a direction perpendicular to the width direction in the facing portion 514. The "longitudinal direction of the facing portion 524" is a direction perpendicular to the width direction in the facing portion 524.

In the present embodiment, the opposing portions 514, 524 in the first inductor 51 and the second inductor 52 are provided in the same layer in the substrate 10. In other words, the opposing portions 514, 524 are provided on the main surface 101 of the substrate 10.

The direction from the first transmission filter 31 (first filter) side to the ground side in the opposing portion 514 of the first inductor 51 is the opposite direction to the direction from the first transmission filter 31 side to the ground side in the opposing portion 524 of the second inductor 52. In other words, a direction from the second terminal P2 side to the first ground terminal G1 side in the opposing portion 514 (right direction in fig. 2) and a direction from the third terminal P3 side to the second ground terminal G2 side in the opposing portion 524 (left direction in fig. 2) are opposite directions in the second direction D2.

As shown in fig. 2, the second inductor 52 and the third inductor 53 face each other at a portion closest to each other. The closest portion of the second inductor 52 and the third inductor 53 to each other is the closest portion in three dimensions. In the case where the second inductor 52 and the third inductor 53 are located on the same plane (main surface 101) as in the example of fig. 2, the closest portion refers to the closest portion on the plane.

Further, in the second inductor 52 and the third inductor 53, the opposing portions are substantially parallel. In more detail, the opposing portion 525 of the second inductor 52 to the third inductor 53 is substantially parallel to the opposing portion 534 of the third inductor 53 to the second inductor 52. Here, "the facing portion 525 is substantially parallel to the facing portion 534" includes a case where the facing portion 525 is completely parallel to the facing portion 534 and a case where an angle formed by the facing portion 525 and the facing portion 534 is 10 degrees or less. The "angle formed by the opposing portion 525 and the opposing portion 534" refers to an angle formed by a line segment along the longitudinal direction of the opposing portion 525 and a line segment along the longitudinal direction of the opposing portion 534. The "longitudinal direction of the facing portion 525" is a direction perpendicular to the width direction in the facing portion 525. The "longitudinal direction of the facing portion 534" is a direction orthogonal to the width direction in the facing portion 534.

In the present embodiment, the opposing portions 525 and 534 in the second inductor 52 and the third inductor 53 are provided in the same layer in the substrate 10. In other words, the opposing portions 525, 534 are disposed on the main surface 101 of the substrate 10.

The direction from the first transmission filter 31 (first filter) side to the ground side in the opposing portion 525 of the second inductor 52 is the opposite direction to the direction from the first transmission filter 31 side to the ground side in the opposing portion 534 of the third inductor 53. In other words, a direction from the third terminal P3 side to the second ground terminal G2 side in the opposing portion 525 (right direction in fig. 2) and a direction from the fourth terminal P4 side to the third ground terminal G3 side in the opposing portion 534 (left direction in fig. 2) are opposite directions in the second direction D2.

(3) Characteristics of multiplexers

Hereinafter, the characteristics of the first transmission filter 31 in the multiplexer 1 will be described with reference to fig. 5. In fig. 5, a characteristic a1 is a filter characteristic of the first transmission filter 31 of the present embodiment. Fig. 5 shows not only the characteristic a1 but also the characteristic a2 and the characteristic A3 as comparative examples. The characteristic a2 is a filter characteristic when the winding directions of the first inductor and the second inductor are different. The characteristic a3 is a filter characteristic in the case where the first inductor and the second inductor are not provided.

Attenuation at the first frequency f1 of the communication Band close to the Band1 Tx (the transmission Band of the Band 1) is achieved by the first parallel-arm resonator 66. Attenuation at the second frequency f2 included in the communication Band of the Band3 Rx (the reception Band of the Band 3) is achieved by the second parallel-arm resonator 67 and the first inductor 51. Attenuation at the fourth frequency f4 of the communication Band (transmission Band of Band 3) included in Band3Tx is realized by the fourth parallel-arm resonator 69 and the third inductor 53.

Attenuation at the third frequency f3 included in the communication Band of the Band32 Rx (the reception Band of the Band 32) is achieved by the third parallel-arm resonator 68 and the second inductor 52. At this time, when the winding direction of the first inductor 51 is the same as the winding direction of the second inductor 52, the first inductor 51 and the second inductor 52 are hard to be magnetically coupled, so that the attenuation amount can be increased. On the other hand, when the first inductor 51 and the second inductor 52 are not provided, the attenuation amount is small as in the characteristic a3, and therefore, a sufficient attenuation effect cannot be obtained. When the winding direction of the first inductor 51 is different from the winding direction of the second inductor 52, the first inductor 51 and the second inductor 52 are magnetically coupled, and therefore the attenuation is insufficient as in the characteristic a 2.

According to the above, in the case where the winding direction of the first inductor 51 is the same as the winding direction of the second inductor 52, attenuation on the communication Band of the Band32 Rx away from the communication Band of the Band1 Tx can be achieved.

In particular, when the transmission signal of Band1 and the reception signal of Band3 are carrier-aggregated as in the present embodiment, the first transmission filter 31 of Band1 can realize attenuation in the reception Band of Band 3. Similarly, in the case where the transmission signal of Band1 is carrier-aggregated with the reception signal of Band32, attenuation in the reception Band of Band32 can be achieved also in the first transmission filter 31 of Band 1. In other words, even in carrier aggregation in which a plurality of signals are simultaneously communicated, attenuation of a frequency band other than a communication frequency band can be achieved.

(4) High frequency module

As shown in fig. 6, the high-frequency module 7 includes a multiplexer 1, a plurality of (2 in the example shown in the figure) power amplifiers 71 and 72, and a plurality of (3 in the example shown in the figure) lnas (low Noise amplifiers) 73 to 75. The power amplifier 71 is a first amplifier connected to the first transmission filter 31 (first filter). The power amplifier 72 is an amplifier connected to the second transmission filter 32. The LNA73 is connected to the first receiving filter 41. The LNA74 is a second amplifier connected to the second reception filter 42 (second filter). The LNA75 is a third amplifier connected to the third receiving filter 43 (third filter).

(5) Communication device

As shown in fig. 6, the communication device 8 includes a high-frequency module 7, a baseband signal processing circuit 81, and an RF signal processing circuit 82. The baseband signal processing circuit 81 and the RF signal processing circuit 82 constitute a signal processing circuit that processes the first transmission signal, the second transmission signal, the first reception signal, the second reception signal, and the third reception signal.

(5.1) Baseband Signal processing Circuit

As shown in fig. 6, the Baseband signal processing Circuit 81 is, for example, a BBIC (Baseband Integrated Circuit), and is electrically connected to the RF signal processing Circuit 82. The baseband signal processing circuit 81 generates an I-phase signal and a Q-phase signal from the baseband signal. The baseband signal processing circuit 81 performs IQ modulation processing by synthesizing the I-phase signal and the Q-phase signal, and outputs a first transmission signal and a second transmission signal. In this case, the first transmission signal and the second transmission signal are generated as modulation signals obtained by amplitude-modulating a carrier signal of a predetermined frequency at a cycle longer than the cycle of the carrier signal.

(5.2) RF Signal processing Circuit

As shown in fig. 6, the RF signal processing circuit 82 is, for example, an RFIC (Radio Frequency integrated circuit), and is disposed between the high-Frequency module 7 and the baseband signal processing circuit 81. The RF signal processing circuit 82 has a function of performing signal processing on the first transmission signal and the second transmission signal from the baseband signal processing circuit 81, and a function of performing signal processing on the first reception signal, the second reception signal, and the third reception signal received by the antenna 9. The RF signal processing circuit 82 is a multiband-compatible processing circuit, and is capable of generating and amplifying transmission signals (a first transmission signal and a second transmission signal) of a plurality of communication bands.

(6) Effect

The multiplexer 1 according to the present embodiment includes a first inductor 51 connected in series to the second parallel arm resonator 67 of the first transmission filter 31 (first filter), and a second inductor 52 connected in series to the third parallel arm resonator 68 of the first transmission filter 31. The winding directions of the first inductor 51 and the second inductor 52 from the first transmission filter 31 side to the ground side are the same. As a result, the first transmission filter 31 through which the first transmission signal (first communication signal) of the Band1 (first communication Band) passes can attenuate in the Band3 (second communication Band) and the Band32 (third communication Band).

(7) Modification example

A modified example of the present embodiment will be described below.

The opposing portions 514 and 524 of the first inductor 51 and the second inductor 52 may be provided on different layers of the substrate 10. In this case, the substrate 10 is a multilayer substrate composed of a plurality of layers.