Dual-band surface acoustic wave filter and composite high-frequency component

A dual-band surface acoustic wave filter is mounted on a circuit board together with a high-frequency switch, constitutes a composite high-frequency component together with the high-frequency switch, and significantly reduces and prevents deterioration of filter characteristics of the composite high-frequency component. A first input terminal is located on a first corner portion of a second principal surface of a wiring board. A second input terminal is located on the second principal surface of the wiring board and along a first long side or a first short side so as to be next to the first input terminal. First and second output terminals are arranged on an edge portion of the second principal surface of the wiring board on a second long side and along the second long side.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dual-band surface acoustic wave filter and a composite high-frequency component. Particularly, the present invention relates to a dual-band surface acoustic wave filter preferably for use in a composite high-frequency component including a high-frequency switch, and a composite high-frequency component including such a dual-band surface acoustic wave filter.

2. Description of the Related Art

In recent years, cellular phones supporting a plurality of communication methods having different frequency bands have been popularized. In such a cellular phone, in order to transmit and receive transmission and reception signals in the plurality of communication methods using a single antenna, a switch module capable of switching among a plurality of transmission and reception signals is used.

For example, Japanese Unexamined Patent Application Publication No. 2007-266840 described below describes a switch module100shown inFIG. 11, as an example of such a switch module.

As shown inFIG. 11, the switch module100includes a circuit board101composed of a plurality of laminated dielectric layers. On a front surface of the circuit board101, a high-frequency switch102, a plurality of surface acoustic wave filters103ato103c, a plurality of chip capacitors104ato104d, and a chip inductor104eare mounted. It should be noted that among the plurality of surface acoustic wave filters103ato103c, each of the surface acoustic wave filters103aand103cis a single-band surface acoustic wave filter including one surface acoustic wave filter portion. Meanwhile, the surface acoustic wave filter103bis a dual-band surface acoustic wave filter including two surface acoustic wave filter portions.

Although not shown, each of output terminals of the surface acoustic wave filters103ato103cis connected via a via-hole electrode continuous in a lamination direction of the circuit board101, to an external terminal formed on a back surface of the circuit board101. Thus, the external terminals of the circuit board101are located almost directly below the output terminals of the surface acoustic wave filters103ato103c, respectively, and hence an output side wiring that connects each output terminal to each external terminal is shortened and two output side wirings next to each other do not overlap each other in the lamination direction and are not close to each other. Therefore, a parasitic impedance and a parasitic capacitance are unlikely to occur.

Further, in this case, near an edge portion of the back surface of the circuit board101on an X1side in an x direction, a plurality of external terminals can be arranged along a y direction perpendicular to the x direction. Thus, wirings that connect the external terminals of the circuit board101to an RF-IC in which a part of an RF circuit at a stage subsequent to the switch module100is integrated can be shortened.

However, in the switch module100shown inFIG. 11, on the front surface of the circuit board101, the plurality of surface acoustic wave filters103ato103care arranged near the edge portion on the x1side and along the y direction, and the high-frequency switch102is arranged near a center of an edge portion on an x2side. Thus, the length dimension, in the y direction, of the space in which the plurality of surface acoustic wave filters103ato103care arranged tends to be larger than the length dimension, in the y direction, of the high-frequency switch102. Therefore, there is a problem that dead spaces occur on both sides of the high-frequency switch102in the y direction and the switch module100is increased in size.

Thus, for example, it is also considered that as shown inFIG. 12, two single-band surface acoustic wave filters103aand103band two single-band surface acoustic wave filters103cand103dare arranged on both sides, respectively, of the high-frequency switch102in the y direction. In this case, a dead space on the circuit board101can be smaller than that when the surface acoustic wave filters103ato103dare arranged linearly. Thus, the switch module can be reduced in size.

In the switch module shown inFIG. 12, unbalanced input terminals105ato105dof the surface acoustic wave filters103ato103dare connected to the high-frequency switch102. Thus, as shown inFIG. 12, the unbalanced input terminals105ato105dare preferably arranged near the high-frequency switch102. When so configured, first and second balanced output terminals106ato106dand107ato107dof the surface acoustic wave filters103ato103dare arranged on the opposite sides of the surface acoustic wave filters103ato103din the y direction with respect to the high-frequency switch102.

Here, when external terminals are provided directly below the output terminals of the surface acoustic wave filters103ato103dsimilarly to the case shown inFIG. 11, a plurality of the external terminals are separately arranged near a y1-side short side and a y2-side short side of the circuit board101in the case shown inFIG. 12. Thus, at least either of the wirings drawn from the y1-side external terminals and the wirings drawn from the y2side bypass and are connected to the RF-IC. As a result, the wirings are longer than existing ones, and hence the area of the board on which the high-frequency switch102and the RF-IC are mounted increases.

Thus, in the case shown inFIG. 12, it is necessary to arrange a plurality of external terminals108ato108hnear the edge portion of the circuit board101on the x1side and along the y direction and to electrically connect these external terminals108ato108hto the first and second balanced output terminals106ato106dand107ato107dof the surface acoustic wave filters103ato103dvia wirings formed on the front surface of the circuit board101and within the circuit board101.

However, as a result of an experiment, the inventor of the present invention has discovered that the filter characteristics of the surface acoustic wave filters of the switch module deteriorate when the arrangement configuration as shown inFIG. 12is used. In other words, when the arrangement configuration as shown inFIG. 12is used, output side wirings110ato110hthat electrically connect the plurality of external terminals108ato108hto the first and second balanced output terminals106ato106dand107ato107d, and input side wirings111ato111dthat electrically connect the high-frequency switch102to the unbalanced input terminal105ato105d, intersect each other in a lamination direction of the circuit board101and are close to each other as shown inFIG. 13. As a result, it was discovered that parasitic components occur between the output side wirings110ato110hand the input side wirings111ato111dand thus isolation between input and output and balance of a balanced output signal deteriorate.

SUMMARY OF THE INVENTION

In view of such discoveries, preferred embodiments of the present invention provide a dual-band surface acoustic wave filter that is mounted on a circuit board together with a high-frequency switch, that constitutes a composite high-frequency component together with the high-frequency switch, and that significantly reduces and prevents deterioration of filter characteristics of the composite high-frequency component, and a composite high-frequency component including the same.

A dual-band surface acoustic wave filter according to a preferred embodiment of the present invention includes a wiring board, a first surface acoustic wave chip, and a second surface acoustic wave chip. The wiring board includes first and second long sides, first and second short sides, a first corner portion defined by the first long side and the first short side, a second corner portion defined by the second long side and the second short side, and first and second principal surfaces. The first surface acoustic wave chip is mounted on the first principal surface of the wiring board. The first surface acoustic wave chip includes a first piezoelectric substrate and a first surface acoustic wave filter portion that is provided on the first piezoelectric substrate. The second surface acoustic wave chip is mounted on the first principal surface of the wiring board. The second surface acoustic wave chip includes a second piezoelectric substrate and a second surface acoustic wave filter portion that is provided on the second piezoelectric substrate. The second surface acoustic wave filter portion has a band different from that of the first surface acoustic wave filter portion. The first surface acoustic wave filter portion includes a first input pad electrode and a first output pad electrode. The second surface acoustic wave filter portion includes a second input pad electrode and a second output pad electrode. A first input terminal, a second input terminal, a first output terminal, and a second output terminal are provided on the second principal surface of the wiring board. The first input terminal is electrically connected to the first input pad electrode. The second input terminal is electrically connected to the second input pad electrode. The first output terminal is electrically connected to the first output pad electrode. The second output terminal is electrically connected to the second output pad electrode. The first input terminal is located on the first corner portion of the second principal surface of the wiring board. The second input terminal is located on the second principal surface of the wiring board and along the first long side or the first short side so as to be next to the first input terminal. The first and second output terminals are arranged on an edge portion on a second-long-side side of the second principal surface of the wiring board and along the second long side.

According to a specific aspect of the dual-band surface acoustic wave filter according to a preferred embodiment of the present invention, the first piezoelectric substrate and the second piezoelectric substrate preferably are integral with each other. According to this configuration, the dual-band surface acoustic wave filter can be reduced in size further.

According to another specific aspect of the dual-band surface acoustic wave filter according to a preferred embodiment of the present invention, each of the first and second surface acoustic wave filter portions has a balance-unbalance conversion function, and the two first output terminals and the two second output terminals are provided.

According to still another specific aspect of the dual-band surface acoustic wave filter according to a preferred embodiment of the present invention, each first output terminal preferably is integral with each second output terminal.

A composite high-frequency component according to another preferred embodiment of the present invention includes the above dual-band surface acoustic wave filter according to a preferred embodiment of the present invention, a high-frequency switch, and a circuit board. The circuit board includes a first principal surface on which the dual-band surface acoustic wave filter and the high-frequency switch are mounted, and a second principal surface facing the first principal surface. The dual-band surface acoustic wave filter is arranged such that a long side of the first principal surface of the circuit board faces the second short side of the dual-band surface acoustic wave filter; and a short side of the first principal surface of the circuit board faces the second long side of the dual-band surface acoustic wave filter. The high-frequency switch is arranged on the first principal surface of the circuit board so as to face the first long side of the dual-band surface acoustic wave filter. A plurality of external terminals are located on the second principal surface of the circuit board so as to be arranged on an edge portion on a side ipsilateral to the long side of the first principal surface of the circuit board and along the long side, and so as to be electrically connected to the first and second output terminals. An input side wiring that electrically connects the first and second input terminals to the high-frequency switch and a plurality of output side wirings that electrically connect the plurality of external terminals to the first and second output terminals are provided in the circuit board.

According to a specific aspect of the composite high-frequency component according to a preferred embodiment of the present invention, the composite high-frequency component includes another dual-band surface acoustic wave filter. The other dual-band surface acoustic wave filter is arranged on the first principal surface of the circuit board such that the first long side thereof faces the high-frequency switch, the second short side thereof faces a long side of the first principal surface of the circuit board, and the second long side thereof faces another short side of the first principal surface of the circuit board. Another plurality of external terminals are arranged on the second principal surface of the circuit board so as to be arranged on an edge portion on a side ipsilateral to the long side of the first principal surface of the circuit board and along the long side with the plurality of external terminals, and so as to be electrically connected to first and second output terminals of the other dual-band surface acoustic wave filter. Another input side wiring that electrically connects first and second input terminals of the other dual-band surface acoustic wave filter to the high-frequency switch and another plurality of output side wirings that electrically connect the other plurality of external terminals to the first and second output terminals of the other dual-band surface acoustic wave filter are provided in the circuit board.

According to various preferred embodiments of the present invention, a dual-band surface acoustic wave filter that is mounted on a circuit board together with a high-frequency switch, that constitutes a composite high-frequency component together with the high-frequency switch, and that can significantly decrease and prevent deterioration of filter characteristics of the composite high-frequency component, and a composite high-frequency component including the same can be provided.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Preferred Embodiment

Hereinafter, preferred embodiments implementing the present invention will be described with a composite high-frequency component1shown inFIGS. 1 and 2as an example. However, the composite high-frequency component1shown inFIGS. 1 and 2is merely illustrative and exemplary. A composite high-frequency component according to the present invention is not limited to the composite high-frequency component1.

The composite high-frequency component1of the present preferred embodiment preferably supports four communication methods, GSM 1800, GSM 1900, GSM 850, and GSM 900. In the composite high-frequency component1, it is possible to switch among transmission and reception signals in the above four communication methods by a high-frequency switch10.

Specifically, as shown inFIG. 1, the composite high-frequency component1includes the high-frequency switch10electrically connected to an antenna terminal11, and six filter portions12to17electrically connected to the antenna terminal11via the high-frequency switch10. The first filter portion12serves as a transmission side filter (Tx) portion for GSM 1800 and GSM 1900. The second filter portion13serves as a transmission side filter (Tx) portion for GSM 850 and GSM 900. The third filter portion14serves as a reception side filter (Rx) portion for GSM 1800. The fourth filter portion15serves as a reception side filter (Rx) portion for GSM 1900. The fifth filter portion16serves as a reception side filter (Rx) portion for GSM 850. The sixth filter portion17serves as a reception side filter (Rx) portion for GSM 900.

The high-frequency switch10is a switch that selectively connects at least one of the first to sixth filter portions12to17to the antenna terminal11. The high-frequency switch10can be, for example, a GaAs switch.

It should be noted that as shown inFIG. 1, the first and second filter portions12and13have functions as low-pass filters. Meanwhile, the third to sixth filter portions14to17have functions as band-pass filters. In addition, the third to sixth filter portions14to17are filter portions having balance-unbalance conversion functions.

As shown inFIG. 2, the composite high-frequency component1includes a rectangular or substantially rectangular circuit board20including a plurality of laminated dielectric layers. The circuit board20includes first and second long sides20A and20B extending along a first direction x and first and second short sides20C and20D extending along a second direction y perpendicular to the first direction x. In addition, the circuit board20includes a first principal surface (front surface)20aand a second principal surface (back surface)20bfacing the first principal surface20a. On the first principal surface20aof the circuit board20, the high-frequency switch10, two dual-band surface acoustic wave filters30aand30b, and other chip components21ato21dare mounted.

Each of the dual-band surface acoustic wave filters30aand30bis a dual-band type surface acoustic wave filter including two surface acoustic wave filter portions having pass bands different from each other. Specifically, the dual-band surface acoustic wave filter30aincludes the third filter portion14and the fourth filter portion15shown inFIG. 1. Meanwhile, the dual-band surface acoustic wave filter30bincludes the fifth filter portion16and the sixth filter portion17.

These dual-band surface acoustic wave filters30aand30bhave generally the same configurations except details such as configurations of IDT electrodes. Thus, the specific configurations of the dual-band surface acoustic wave filters30aand30bwill be described with reference toFIG. 3, which is a schematic cross-sectional view of the dual-band surface acoustic wave filter30a, andFIGS. 4 to 6.

As shown inFIGS. 3 to 5, the dual-band surface acoustic wave filter30aincludes a rectangular or substantially rectangular wiring board31including a plurality of laminated dielectric layers. As shown inFIGS. 4 and 5, the dual-band surface acoustic wave filter30aincludes first and second long sides31A and31B, first and second short sides31C and31D, a first corner portion31E defined by the first long side31A and the first short side31C, and a second corner portion31F defined by the second long side31B and the second short side31D. In addition, as shown inFIGS. 3 to 5, the wiring board31includes a first principal surface (front surface)31aand a second principal surface (back surface)31bfacing the first principal surface31a.

As shown inFIG. 3, a surface acoustic wave chip32is flip-chip bonded on the first principal surface31aof the wiring board31and sealed by a resin package34. The surface acoustic wave chip32is a chip in which a first surface acoustic wave chip having the third filter portion14shown inFIG. 1and a second surface acoustic wave chip including the fourth filter portion15preferably are integral with each other.

As shown inFIG. 6, the surface acoustic wave chip32includes a piezoelectric substrate33in which a piezoelectric substrate of the first surface acoustic wave chip and a piezoelectric substrate of the second surface acoustic wave chip preferably are integral with each other. The piezoelectric substrate33can be made of an appropriate piezoelectric material. The piezoelectric substrate33can be made of LiNbO3, LiTaO3, crystal, or other suitable material, for example.

It should be noted that the first surface acoustic wave chip and the second surface acoustic wave chip may be separately provided by separately providing the piezoelectric substrates thereof.

On the piezoelectric substrate33, a first surface acoustic wave filter portion35constituting the third filter portion14and a second surface acoustic wave filter portion36constituting the fourth filter portion15are provided. The second surface acoustic wave filter portion36has a pass band different from that of the first surface acoustic wave filter portion35. In other words, in the present preferred embodiment, the reception frequency band of the second surface acoustic wave filter portion36is different from the reception frequency band of the first surface acoustic wave filter portion35.

The first surface acoustic wave filter portion35is a so-called balance type surface acoustic wave filter portion having a balance-unbalance conversion function. The first surface acoustic wave filter portion35includes a first input pad electrode35aand two first output pad electrodes35b1and35b2. A longitudinally-coupled resonator type surface acoustic wave element35cis electrically connected between the first input pad electrode35aand the two first output pad electrodes35b1and35b2. A surface acoustic wave resonator35dis electrically connected between the longitudinally-coupled resonator type surface acoustic wave element35cand the first output pad electrode35b1. A surface acoustic wave resonator35eis electrically connected between the longitudinally-coupled resonator type surface acoustic wave element35cand the first output pad electrode35b2.

Similarly to the first surface acoustic wave filter portion35, the second surface acoustic wave filter portion36is also a so-called balance-type surface acoustic wave filter portion having a balance-unbalance conversion function. The second surface acoustic wave filter portion36includes a second input pad electrode36aand two second output pad electrodes36b1and36b2. A longitudinally-coupled resonator type surface acoustic wave element36cis electrically connected between the second input pad electrode36aand the two second output pad electrodes36b1and36b2. A surface acoustic wave resonator36dis electrically connected between the longitudinally-coupled resonator type surface acoustic wave element36cand the second input pad electrode36a.

The first and second input pad electrodes35aand36aand the first and second output pad electrodes35b1,35b2,36b1, and36b2are electrically connected to electrodes38ato38fprovided on the first principal surface31aof the wiring board31as shown inFIG. 4, via bumps. Specifically, the first input pad electrode35ais electrically connected to the electrode38a. The second input pad electrode36ais electrically connected to the electrode38b. The first output pad electrode35b1is electrically connected to the electrode38c. The first output pad electrode35b2is electrically connected to the electrode38d. The second output pad electrode36b1is electrically connected to the electrode38e. The second output pad electrode36b2is electrically connected to the electrode38f. The ground pad electrodes37ato37care electrically connected to an electrode38gelectrically connected to a ground potential, via bumps. It should be noted that other electrodes38hand38iare dummy electrodes.

The electrode38ato38fare electrically connected via wirings40located within the wiring board31and schematically shown inFIG. 3, to input and output terminals39ato39flocated on the second principal surface (back surface)31bof the wiring board31as shown inFIG. 5. Specifically, the electrode38aelectrically connected to the first input pad electrode35ais electrically connected to the first input terminal39a. The electrode38belectrically connected to the second input pad electrode36ais electrically connect to the second input terminal39b. The electrode38celectrically connected to the first output pad electrode35b1is electrically connected to the first output terminal39c. The electrode38delectrically connected to the first output pad electrode35b2is connected to the first output terminal39d. The electrode38eelectrically connected to the second output pad electrode36b1is connected to the second output terminal39e. The electrode38felectrically connected to the second output pad electrode36b2is connected to the second output terminal39f.

As shown inFIG. 5, the first input terminal39ais located on the first corner portion31E of the second principal surface31bof the wiring board31. The first input terminal39afaces the first long side31A and the first short side31C. The second input terminal39bis located on the second principal surface31bof the wiring board31and along the first long side31A so as to be next to the first input terminal39a. In other words, the first and second input terminals39aand39bare arranged on the first corner portion31E side of the edge portion on the first long side31A side. Meanwhile, the first and second output terminals39cto39fare arranged on the edge portion of the second principal surface31bof the wiring board31on the second long side31B side and at equal intervals along the second long side31B.FIG. 5is a perspective plan view illustrating the first and second input terminals39aand39band the first and second output terminals39cto39fwhen seen through from the first principal surface31aside of the wiring board31. In addition, each of terminals other than the input and output terminals39ato39finFIG. 5is a ground terminal or a dummy terminal.

Next, a mode in which the high-frequency switch10and the two dual-band surface acoustic wave filters30aand30bare mounted on the first principal surface (front surface)20aof the circuit board20will be described mainly with reference toFIG. 2.

As shown inFIG. 2, the high-frequency switch10and the two dual-band surface acoustic wave filters30aand30bare arranged along the first direction x that is a direction in which the first and second long sides20A and20B of the circuit board20extend. Among the high-frequency switch10and the two dual-band surface acoustic wave filters30aand30b, the high-frequency switch10is located at the center in the first direction x. The dual-band surface acoustic wave filter30ais located on the x1side in the first direction x with respect to the high-frequency switch10. Meanwhile, the dual-band surface acoustic wave filter30bis located on the x2side in the first direction x with respect to the high-frequency switch10.

The dual-band surface acoustic wave filter30ais arranged such that the first long side20A of the first principal surface20aof the circuit board20faces the second short side31D of the dual-band surface acoustic wave filter30a; and the first short side20C of the first principal surface20aof the circuit board20faces the second long side31B of the dual-band surface acoustic wave filter30a.

The dual-band surface acoustic wave filter30bis arranged such that the first long side20A of the first principal surface20aof the circuit board20faces the second short side31D of the dual-band surface acoustic wave filter30b; and the second short side20D of the first principal surface20aof the circuit board20faces the second long side31B of the dual-band surface acoustic wave filter30b. It should be noted that the dual-band surface acoustic wave filter30bis configured such that the first and second input terminals39aand39band the first and second output terminals39cto39fare arranged to be mirror-symmetrical to the dual-band surface acoustic wave filter30a.

The high-frequency switch10preferably has a rectangular or substantially rectangular shape and is arranged on the first principal surface20aof the circuit board20so as to face the first long sides31A of the dual-band surface acoustic wave filters30aand30b. Thus, the first and second input terminals39aand39bof the dual-band surface acoustic wave filters30aand30bare located adjacent to the high-frequency switch10. The first and second input terminals39aand39bare electrically connected to the high-frequency switch10via input side wirings41aand41band via-hole electrodes which are provided within the circuit board20.

Meanwhile, the first and second output terminals39cto39fare electrically connected to a plurality of external terminals43ato43hlocated on the second principal surface (back surface)20bof the circuit board20. These external terminals43ato43hare arranged on an edge portion of the second principal surface20bof the circuit board20on the first long side20A side and along the first long side20A.

Specifically, in the present preferred embodiment, the first output terminal39cof the dual-band surface acoustic wave filter30ais electrically connected to the external terminal43cvia an output side wiring42aand a via-hole electrode which are located within the circuit board20. The first output terminal39dof the dual-band surface acoustic wave filter30ais electrically connected to the external terminal43dvia an output side wiring42band a via-hole electrode which are located within the circuit board20. The second output terminal39eof the dual-band surface acoustic wave filter30ais electrically connected to the external terminal43bvia an output side wiring42cand a via-hole electrode which are located within the circuit board20. The second output terminal39fof the dual-band surface acoustic wave filter30ais electrically connected to the external terminal43avia an output side wiring42dand a via-hole electrode which are located within the circuit board20.

Further, the first output terminal39cof the dual-band surface acoustic wave filter30bis electrically connected to the external terminal43fvia an output side wiring42eand a via-hole electrode which are located within the circuit board20. The first output terminal39dof the dual-band surface acoustic wave filter30bis electrically connected to the external terminal43evia an output side wiring42fand a via-hole electrode which are located within the circuit board20. The second output terminal39eof the dual-band surface acoustic wave filter30bis electrically connected to the external terminal43gvia an output side wiring42gand a via-hole electrode which are located within the circuit board20. The second output terminal39fof the dual-band surface acoustic wave filter30bis electrically connected to the external terminal43hvia an output side wiring42hand a via-hole electrode which are located within the circuit board20.

It should be noted that the chip components21ato21bare arranged on an edge portion of the first principal surface20aof the circuit board20on the y2side in the second direction y with respect to the high-frequency switch10and the dual-band surface acoustic wave filters30aand30band along the first direction x.

Each of the first and second filter portions12and13preferably includes an LC resonant circuit composed of a wiring pattern that is located within the circuit board20and not shown.

As described above, in the present preferred embodiment, the first input terminal39ais located on the first corner portion31E. The second input terminal39bis arranged along the first long side31A so as to be next to the first input terminal39a. The first and second output terminals39cto39fare arranged on the edge portion on the second long side31B side and along the second long side31B. Thus, even when the external terminals43ato43hof the composite high-frequency component1are arranged on the edge portion on the first long side20A side in order to cause a wiring, which connects the composite high-frequency component1to an RF-IC at a subsequent stage, to be the shortest, it can effectively be suppressed that the input side wirings41aand41band the output side wirings42ato42hintersect each other in a lamination direction of the circuit board20and are close to each other. Thus, occurrence of an unwanted parasitic component can effectively be significantly reduced and prevented. Therefore, deterioration of filter characteristics such as isolation between input and output and balance of a balanced output signal can be significantly reduced and prevented.

Hereinafter, this effect will be described in more detail on the basis of a specific example.

FIG. 7is a graph showing the insertion loss of a fourth filter portion in a composite high-frequency component according to an example of a preferred embodiment of the present invention and the insertion loss of a fourth filter portion in a composite high-frequency component according to a comparative example.FIG. 8is a graph showing the amplitude balance of the fourth filter portion in the composite high-frequency component according to the example of a preferred embodiment of the present invention and the amplitude balance of the fourth filter portion in the composite high-frequency component according to the comparative example.FIG. 9is a graph showing the phase balance of the fourth filter portion in the composite high-frequency component according to the example of a preferred embodiment of the present invention and the phase balance of the fourth filter portion in the composite high-frequency component according to the comparative example.

The composite high-frequency component according to the example of a preferred embodiment of the present invention which is shown inFIGS. 7 to 9preferably has the same configuration as that of the composite high-frequency component1according to the first preferred embodiment described above, and the composite high-frequency component according to the comparative example has the same configuration as that of the example except that the arrangement configuration of parts shown inFIG. 12and the layout of the internal wirings of the circuit board shown inFIG. 13are used. As shown inFIG. 7, isolation between input and output less deteriorates in the example in which the configuration of the first preferred embodiment is used, than in the comparative example. Thus, the insertion loss is low in the pass band, and an amount of attenuation is large in the outside of the pass band on the high frequency side. In addition, as shown inFIGS. 8 and 9, it appears that the balance of a balanced output signal is better in the example than in the comparative example. Due to the above, it appears that when the configuration of the first preferred embodiment described above is used, good filter characteristics are obtained.

Further, when the arrangement of the first and second input terminals39aand39band the first and second output terminals39cto39fin the dual-band surface acoustic wave filters30aand30bof the first preferred embodiment is used, flexibility in arranging the input side wirings41aand41band the output side wirings42ato42hof the circuit board20can be increased. Moreover, when the arrangement of the high-frequency switch10and the dual-band surface acoustic wave filters30aand30bon the circuit board20of the first preferred embodiment is used, the composite high-frequency component1can be reduced in size.

It should be noted that in the first preferred embodiment described above, the case has been described where the first and second input terminals39aand39bare preferably arranged along the first long side31A. However, the present invention is not limited to this configuration. For example, the first and second input terminals39aand39bcan be next to each other, and may be arranged along the first short side31C of the wiring board31.

Further, in the first preferred embodiment described above, the case has been described where in each of the dual-band surface acoustic wave filters30aand30b, all the first and second output terminals39cto39fare preferably arranged along the second long side31B. However, the present invention is not limited to this configuration. In the present invention, it suffices that at least either one of the two first output terminals and at least either one of the two second output terminals in the dual-band surface acoustic wave filter are arranged on the second long side31B side, and the other first output pad electrode or second output pad electrode may be arranged on the first short side31C side or on the second short side31D side.

Further, in the first preferred embodiment described above, the case has been described where the first and second surface acoustic wave filter portions of each dual-band surface acoustic wave filter preferably are a balance type and the four output terminals are provided in total. However, the present invention is not limited to this configuration. For example, the output terminals of the first surface acoustic wave filter portion may also be used as the output terminals of the second surface acoustic wave filter portion. In addition, the first and/or second surface acoustic wave filter portions may be an unbalance type which does not have a balance-unbalance conversion function. In these cases, two output terminals may be provided. For example, in an example shown inFIG. 10, two output terminals, namely, an output terminal39xin which the first output terminal39cand the second output terminal39epreferably are integral with each other and an output terminal39yin which the first output terminal39dand the second output terminal39fpreferably are integral with each other, are provided. In the example shown inFIG. 10, preferably, the output terminals39xand39yare arranged on the second corner portion31F, and the first and second input terminals39aand39bare arranged on the first corner portion31E. In other words, the output terminals39xand39yand the first and second input terminals39aand39bare preferably arranged in a diagonal relation.

It should be noted that in the example shown inFIG. 10, the case has been described where the output terminals39xand39yand the first and second input terminals39aand39bpreferably are arranged along the long sides, respectively, but the output terminals39xand39yand the first and second input terminals39aand39bmay be arranged along the short sides, respectively.

When the output terminals39xand39yand the first and second input terminals39aand39bare arranged as described above, the flexibility in arranging the input side wirings41aand41band the output side wirings42ato42hof the circuit board20can be increased further.