JP2010041316A - High-pass filter, high frequency module, and communication equipment using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pass filter whose bandwidth is increased, a high frequency module, and communication equipment using the same. <P>SOLUTION: In a laminate high-pass filter, an inductance element includes: first coil patterns Lhs 1b, Lhs 1d, Lhs 2b, Lhs 2d which are formed on a dielectric layer to constitute a coil exceeding 1/2 turns; and second coil patterns Lhs 1a, Lhs 1c, Lhs 2a, Lhs 2c which are formed on a dielectric layer different from that of the first coil patterns to constitute a coil exceeding 1/2 turns, one-side ends of the first and second coil patterns are serially connected to form a spiral coil, a first coil cross section which is formed when the first coil pattern is extended to one turn is smaller than a second coil cross section which is formed when the second coil pattern is extended to one turn, and the first coil cross section does not protrude from the second coil cross section when viewed from the lamination direction of a laminate substrate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a high-pass filter used in a wireless communication device such as a wireless LAN that performs wireless transmission between mobile communication devices such as mobile phones and electronic / electrical devices, and a high-frequency module using the same.

  At present, data communication using a wireless LAN represented by the IEEE 802.11 standard is widely used. Wireless LANs are, for example, personal computers (PCs), PC peripherals such as printers and hard disks, FAX, standard televisions (SDTVs), high-definition televisions (HDTVs), mobile phones and other electronic devices, automobiles and airplanes. Adopted as a signal transmission means instead of wired communication, wireless data transmission is performed between each electronic device.

  A high-frequency circuit used in such a multiband communication apparatus using a wireless LAN is one that can be transmitted and received by two communication systems (IEEE802.11a and IEEE802.11b and / or IEEE802.11g) having different communication frequency bands. The high frequency switch for switching the connection between the antenna and the transmission side circuit and the reception side circuit is provided, and the transmission side circuit and the reception side circuit of the two communication systems are switched. With the downsizing and high functionality of wireless devices, there is a strong demand for miniaturization while integrating many high frequency modules into high frequency modules that implement the high frequency circuit. It is essential.

  Of the circuits used in such a high-frequency module, a high-pass filter that passes a signal having a predetermined frequency or higher is an important component of the communication device. The high-pass filter is disposed between the front end of the antenna circuit, the circuit of the transmission / reception circuit, and the like, and is used for prevention of saturation of the LNA (low noise amplifier) on the reception side due to unnecessary waves, ESD (electrostatic breakdown) countermeasures, and the like.

  FIG. 7 shows an equivalent circuit diagram of a high-frequency module provided with a high-pass filter (lower right HPF 502 in the figure) disclosed in Patent Document 1. A capacitive element RCc1 connected in series to the signal path between the input / output terminals P501 and P503, and an inductance element RLt2 having one end connected to the signal path between the input / output terminals and the other end grounded via the capacitive element RCt2. Prepare.

  FIG. 8 shows a part of the laminated pattern of the high-frequency module that realizes the equivalent circuit of FIG. The high-frequency module according to FIG. 8 is composed of 20 layers of dielectrics. The high-pass filter HPF 502 in FIG. 7 has one end of the coil pattern RLt2 connected in series in FIG. 8, and a spiral coil is formed across the six layers from the dielectric layer 7 to the dielectric layer 12.

  In FIG. 8, the coil pattern RLt2 is formed, for example, when the coil cross section formed when the coil pattern of the dielectric layer 8 is extended to one turn and when the coil pattern of the dielectric layer 9 is extended by one turn. The coil cross section is the same. The same applies to the dielectric layers 10 to 12. That is, the coil pattern has the same coil cross section in each layer.

  In multiband communication, a high-pass filter may be arranged at the antenna top to prevent ESD or prevent saturation of a low-noise amplifier. In this case, the high-pass filter needs to pass signals in a plurality of communication bands, and the high-pass filter needs to be widened.

JP 2008-48450 A

  However, in the high-pass filter described in Patent Document 1, the coil pattern RLt2 is formed of a plurality of layers, and the coil electrodes of the respective layers have parasitic capacitances.

  Accordingly, an object of the present invention is to provide a high-pass filter that is small in size but has a wide band, a high-frequency module using the high-pass filter, and a communication device using the high-frequency module.

  The high-pass filter according to the present invention includes a pair of input / output terminals, a capacitive element connected in series to a signal path between the input / output terminals, one end connected to the signal path between the input / output terminals, and the other end grounded A high-pass filter comprising a laminated substrate formed by laminating a plurality of dielectric layers, wherein the inductance element is formed on the dielectric layer and has a half turn or more. A first coil pattern that forms a coil portion and a second coil pattern that is formed in a different dielectric layer from the first coil pattern and forms a coil portion of more than 1/2 turn, The first and second coil patterns have one end connected in series to form a spiral coil, and the first coil cross section formed when the first coil pattern is extended to one turn is 2 is smaller than the second coil cross section formed when the coil pattern is extended to one turn, and the first coil cross section is viewed from the second coil cross section when viewed from the stacking direction of the multilayer substrate. This is a high-pass filter that does not protrude. According to such a configuration, it is possible to reduce the overlap of the first coil pattern and the second coil pattern forming the inductance element as viewed from the stacking direction, and to suppress the parasitic capacitance between the wirings of the inductance element. A broadband high-pass filter can be realized.

  The high-pass filter includes a plurality of at least one of the first coil pattern and the second coil pattern, and the first coil pattern and the second coil pattern are arranged in a stacking direction of the stacked substrate. It is preferable that they are alternately arranged on different dielectric layers, and are connected in series to form a helical coil. According to such a configuration, by forming the coil that forms the inductance element with a plurality of layers, the high-pass filter can be reduced in size even when a large inductance is formed, and the parasitic capacitance between the wires of the inductance element can also be reduced. Therefore, a small and wide band high-pass filter can be realized.

  Further, in the high pass filter, the capacitive electrode having another capacitive element connected in series to the inductance element, wherein the capacitive electrode forming the other capacitive element is seen from the lamination direction of the multilayer substrate, the second coil cross section It is preferable that the portion of the spiral coil closest to the capacitive electrode is the first coil pattern. According to this configuration, the capacitive element and the inductance element can be formed in the same region with respect to the stacking direction. Further, by setting the portion of the spiral coil closest to the capacitor electrode as the first coil pattern, the parasitic capacitance formed by the spiral coil facing another electrode such as the capacitor electrode is reduced. can do.

  The high-pass filter includes another capacitive element connected in series to the inductance element, and the capacitive electrode forming the other capacitive element is a cross section of the second coil as viewed from the lamination direction of the multilayer substrate. It is also preferable that a ground electrode is disposed between the spiral coil and the capacitive electrode. According to this configuration, the parasitic capacitance between the inductance element and the capacitive element can be reduced by the ground electrode disposed between the capacitive element and the inductance element, and a wideband high-pass filter can be realized.

  Furthermore, in the high-pass filter, a plurality of capacitive electrodes forming a capacitive element connected in series in a signal path between the input / output terminals are formed on a dielectric layer different from the spiral coil, and the spiral coil The coil pattern closest to the plurality of capacitive electrodes when viewed from the stacking direction of the multilayer substrate is a coil portion of at least a half turn of the coil pattern of the multilayer substrate. It is preferable that it does not overlap with the capacitive electrode closest to the spiral coil when viewed from the stacking direction. According to this configuration, it is possible to reduce the parasitic capacitance between the capacitive electrode that forms the capacitive element connected in series in the signal path between the input and output terminals and the coil pattern that forms the spiral coil.

  The high-pass filter further includes a plurality of the inductance elements having one end connected to a signal path between the input / output terminals and the other end grounded, wherein the spiral coil of each inductance element is perpendicular to the stacking direction. Are preferably arranged in parallel. According to such a configuration, by increasing the number of stages of circuits constituting the high-pass filter, it is possible to obtain a characteristic with a wider band and a large attenuation. In addition, since the parasitic capacitance between the wires of the inductance element and the parasitic capacitance between the inductance element and the capacitance element can be reduced at each stage, a broadband high-pass filter can be realized.

  Furthermore, in the high-pass filter, it is preferable that the magnetic field generation direction of the spiral coil of each inductance element is opposite between adjacent inductance elements. It is also possible to attenuate a desired band by adjoining the helical coils of the inductance elements and magnetically coupling the inductance elements.

  Further, in the high-pass filter, in the adjacent inductance elements, the first coil patterns and the second coil patterns arranged on the same dielectric layer are substantially line symmetric with respect to the center line therebetween. It is preferable to be formed. As a result, the reflection characteristics at the input and output are symmetric, and the design is facilitated.

  The high-frequency module according to the present invention is a high-frequency module used for switching between transmission and reception of two or more communication systems having different frequency bands, and includes an antenna terminal, a transmission terminal and a reception terminal of each communication system, and the antenna terminal. The transmission / reception path having a high-frequency switch circuit that switches a connected transmission / reception path between a transmission path connected to the transmission terminal and a reception path connected to the reception terminal, and through which signals of the two or more communication systems flow The high-pass filter having a pass band that is a frequency band of the two or more communication systems is disposed in at least one of the reception paths. Thereby, in a high frequency module for multiband used in a wireless LAN or the like, unnecessary signals on the low frequency side can be attenuated while passing signals of two or more communication systems to be used.

  In the high-frequency module, one of the high-pass filters is arranged in the transmission / reception path and the reception path through which signals of the two or more communication systems flow, and each coil pattern of the high-pass filter arranged in the transmission / reception path and the reception Each coil pattern of the high-pass filter disposed in the path is preferably formed on the same dielectric layer of the multilayer substrate. Thereby, it is possible to realize a high-frequency module that can be applied to a wider band. In addition, the high-frequency module can be reduced in height by sharing the dielectric layer among the spiral coil patterns.

  The communication device of the present invention is characterized by using the high-frequency module.

  ADVANTAGE OF THE INVENTION According to this invention, a small-sized and broadband high-pass filter, a high frequency module, and a communication apparatus using the same can be provided.

  The present invention provides a multilayer high-pass filter having a coil pattern in a plurality of layers, a coil having a large coil cross section (large diameter) and a small coil cross section so as to reduce overlapping of the coil patterns as viewed from the stacking direction ( By alternately laminating coils with small diameters, the parasitic capacitance of the inductance element is reduced, and the broadband of the high-pass filter is achieved.

1 (a) to 1 (d), a pair of input / output terminals, a capacitive element connected in series to a signal path between these input / output terminals, and one end connected to the signal path between the input / output terminals. An example of an equivalent circuit of the high-pass filter according to the present invention including an inductance element having the other end grounded is shown. The high-pass filter shown in FIG. 1A includes a capacitive element C11 connected in series to a signal path between a pair of input / output terminals T _in / T _out , and one end of the signal path between the input / output terminals T _in / T _out ( and connected to a path) between the T _out and C11, and an inductance element L11 which is grounded at the other end.

The high-pass filter shown in FIG. 1B has a capacitive element C21 connected in series to a signal path between a pair of input / output terminals T _in / T _out and one end connected to the signal path between the input / output terminals T _in / T _out. And an inductance element L21 having the other end grounded. Further, a grounded capacitive element C22 is connected in series to the ground side of the inductance element L21. Such a configuration is shown in FIG. 1A in that another capacitive element C22 is connected in series to the inductance element in addition to the capacitive element connected in series to the signal path between the input / output terminals T _in / T _out . Different from high pass filter. In order to adjust the position of the attenuation pole according to the required characteristics of the high-pass filter, the presence / absence of the capacitive element and the capacitance value can be appropriately selected.

The high-pass filter shown in FIG. 1C includes a capacitive element C31 connected in series to a signal path between a pair of input / output terminals T _in / T _out and one end connected to a signal path between the input / output terminals T _in / T _out. An inductance element L31 that is connected and grounded at the other end is provided. Such a configuration includes an inductance element L31 having one end connected to a signal path between the input / output terminals T _in / T _out (path between T _in and C31) and the other end grounded, as shown in FIG. Different from the high-pass filter shown. A high-pass filter according to this embodiment, for example, by connecting the input and output terminals T _in the antenna terminal of the front end module, a subsequent IC etc. of the front end module is suitable for a case to protect against ESD voltage.

The high-pass filter shown in FIG. 1 (d) includes capacitive elements C41, C43 and C45 connected in series in a signal path between the input / output terminals T _in / T _out , and one end of the signal between the input / output terminals T _in / T _out. Inductance elements L41 and L42 connected to the path and grounded at the other end via capacitive elements C42 and C44, respectively. One end of the inductance element L41 is connected between the capacitive element C41 and the capacitor C43 of the signal path between the input and output terminals _T in _{/ T out,} one end of the inductance element L42 is between the input and output terminals _T in _{/ T out} Are connected between the capacitive element C43 and the capacitive element C45. The high-pass filter according to this embodiment is inserted in a reception-side path between a change-over switch such as a single pole dual throw (SPDT) in a high-frequency module and a low-noise amplifier LNA, for example. This is suitable for securing a high attenuation outside the band.

  The structure of the high-pass filter of the present invention will be described in detail below with reference to the drawings, but the present invention is not limited to these. The high-pass filter according to the present invention may be a high-pass filter in which an inductance element and a capacitive element are combined, and the circuit configuration is not limited to the configuration shown in FIG. Depending on where the attenuation pole of the filter is set, the connection position of the capacitive element may be changed as appropriate.

  The embodiment of the present invention will be described below in comparison with the conventional example shown in FIG. In the high-pass filter in the conventional example shown in FIG. 8, the coil pattern RLt2 includes, for example, a coil cross section formed when the seventh layer coil pattern is extended to one turn and the eighth layer coil pattern extended to one turn. The coil sections formed in the case have the same shape and the same size. The same applies to the ninth to twelfth layers. That is, the plurality of coil patterns RLt2 formed over the seventh to twelfth layers have a coil cross section that is projected and superimposed from the stacking direction. Moreover, in the adjacent layers, two orthogonal linear portions overlap each other in the rectangular coil pattern when extended to one turn. Therefore, it has been found that in the conventional high-pass filter as shown in FIG. 8, a large parasitic capacitance is generated between the plurality of coil patterns RLt2, which narrows the band.

The high-pass filter according to the present invention solves the above problem by a new configuration relating to the coil pattern. FIG. 2 is a lamination pattern diagram of a high-pass filter in which the equivalent circuit shown in FIG. 1D is configured using a laminated substrate in which a plurality of dielectric layers are laminated. The high-pass filter shown in FIG. 2 is formed of eleven dielectric layers of first to eleventh layers. In the first layer, electrodes corresponding to the pair of input / output terminals T _in / T _out are formed. Capacitance electrodes that form capacitive elements C41, C43, and C45 connected in series in the signal path between the input / output terminals T _in / T _out are arranged from the second layer to the fifth layer. Capacitance electrodes Chs1a and Chs1b formed in the second layer and the fourth layer and connected by via electrodes are opposed to capacitance electrodes Chs3b and Chs3f formed in the third layer and the fifth layer and connected by via electrodes. Thus, the capacitive element C41 is formed. Similarly, capacitive electrodes Chs5a and Chs5b formed in the second layer and the fourth layer and connected by via electrodes are formed in the third layer and the fifth layer, and capacitive electrodes Chs3c and Chs3g connected by via electrodes and The capacitive element C45 is formed by facing each other. Capacitance electrodes Chs3a and Chs3e whose one ends are connected to Chs3c and chs3g by via electrodes are formed in the second layer and the fourth layer. Such capacitive electrodes Chs3a and Chs3e are opposed to a part of the capacitive electrodes Chs3b and Chs3f, thereby forming the capacitive element C43.

In the sixth to ninth layers, inductance elements L41 and L42 having one end connected to the signal path between the input / output terminals T _in / T _out and the other end grounded in the equivalent circuit of FIG. Coil patterns Lhs1a to Lhs1d and coil patterns Lhs2a to Lhs2d to be formed are formed. The coil patterns Lhs1a to Lhs1d and the coil patterns Lhs2a to Lhs2d each form one end of the coil pattern connected in series to form a spiral coil. In the tenth layer, capacitive electrodes Chs2 and Chs4 are formed, which form the other capacitive elements C42 and C44 connected in series to the inductance element in the equivalent circuit of FIG. Capacitance electrodes Chs2 and Chs4 constitute a grounded capacitance facing the ground layer formed in the eleventh layer.

  The inductance element L41 is a dielectric layer different from the first coil pattern Lhs1d, which is formed in the ninth dielectric layer and forms a coil portion of more than 1/2 turn, and the first coil pattern Lhs1d. A second coil pattern Lhs1c is formed on the eighth layer and constitutes a coil portion of more than 1/2 turn. Then, the first coil pattern Lhs1d and the second coil pattern Lhs1c are interlayer-connected by via holes to form a spiral coil. Similarly, the inductance element L42 includes a first coil pattern Lhs2d that is formed in the ninth dielectric layer and forms a coil portion of more than 1/2 turn, and a dielectric layer different from the first coil pattern Lhs2d. The second coil pattern Lhs2c is formed in the eighth layer and constitutes a coil portion of more than 1/2 turn. In the configuration shown in FIG. 2, each coil pattern is approximately 3/4 turns composed of three sides of a one-turn rectangular coil. Then, the first coil pattern Lhs2d and the second coil pattern Lhs2c are interconnected by via holes to form a spiral coil.

  The relationship between the first coil patterns Lhs1d and Lhs2d formed on the ninth layer and the second coil patterns Lhs1c and Lhs2c formed on the eighth layer will be described with reference to FIG. FIG. 3 shows the second coil patterns Lhs1c and Lhs2c ((a) (i)) formed on the eighth layer, and the first coil patterns Lhs1d and Lhs2d ((b) (i) formed on the ninth layer. )), And the positional relationship ((c) (i)) of the coil patterns of the eighth layer and the ninth layer seen from the lamination direction. Moreover, the coil cross section formed when each coil pattern shown to (a)-(b) is extended to 1 turn was shown as (ii). In the plane perpendicular to the winding axis direction of the coil (surface of each dielectric layer), the shaded portion in the figure is the coil cross section. Each coil pattern is constituted by three linear patterns orthogonal to each other, and constitutes a coil portion having more than 1/2 turn. The coil cross section formed when each coil pattern is extended to one turn is the two linear patterns facing each other when the coil pattern is composed of three linear patterns orthogonal to each other as shown in FIG. The rectangular area | region which makes the outer side of the longer pattern and the outer side of the pattern orthogonal to the two patterns the two orthogonal sides. In addition, when the coil pattern is configured by four linear patterns orthogonal to each other, it indicates a rectangular region configured by the outer sides of the rectangular frame-shaped pattern configured when each linear pattern is extended. In the case of the embodiment shown in FIG. 2, the coil cross section formed when extending to one turn is a rectangle, but is not necessarily limited to a rectangle.

  The first coil cross section formed when the first coil pattern Lhs1d (Lhs2d) is extended to one turn is the second coil cross section formed when the second coil pattern Lhs1c (Lhs2c) is extended to one turn. It is designed to be smaller than the coil cross section. That is, in other words, of the two coil patterns, the coil pattern having a relatively small coil cross section is the first coil pattern. Moreover, the first coil cross section does not protrude from the second coil cross section when viewed from the stacking direction of the multilayer substrate. In other words, when each coil pattern is extended to one turn, the outer periphery of the first coil pattern viewed from the stacking direction is arranged to be inside the outer periphery of the second coil pattern. As a result, the overlap of the first coil pattern Lhs1d (Lhs2d) and the second coil pattern Lhs1c (Lhs2c) forming the inductance element as viewed from the stacking direction can be reduced, and the parasitic capacitance between the inductance wirings can be suppressed. A high-pass filter can be realized. Even if a part of the first coil pattern and the second coil pattern overlap, the first coil cross section is made smaller than the second coil cross section so that it does not protrude from the second coil cross section. The parasitic capacitance is reduced. In the configuration shown in FIG. 2, the first coil pattern Lhs1d (Lhs2d) and the second coil pattern Lhs1c (Lhs2c) themselves are arranged so as not to overlap when viewed from the stacking direction, except for the portion related to the via electrode. Yes. Such a configuration further enhances the effect of parasitic capacitance suppression. It is possible to avoid overlapping of coil patterns between adjacent dielectric layers by forming coil patterns of 1/2 turn or less on each dielectric layer and connecting them. Since many dielectric layers are required to form a spiral coil, the high-pass filter cannot be reduced in size.

  In the embodiment shown in FIG. 2, first coil patterns Lhs1b and Lhs2b having a smaller coil cross section than the second coil pattern are formed on the seventh layer, and the first layer of the seventh layer is formed on the sixth layer. Second coil patterns Lhs1a and Lhs2a having a larger coil cross section than the coil patterns Lhs1b and Lhs2b are formed. From the sixth layer to the ninth layer, the first coil pattern and the second coil pattern are alternately arranged in different dielectric layers in the stacking direction of the stacked substrate, and are connected in series to each other in a spiral coil. Is forming. That is, coil patterns having relatively different coil cross-sectional sizes are arranged so that the coil cross-sections are alternately large and small. The structure having at least one of the first coil pattern and the second coil pattern while suppressing the overlap between the first coil pattern and the second coil pattern can increase the inductance of the inductance element of the high-pass filter. In spite of this, it is possible to realize a small and wide band high-pass filter. The first coil patterns formed on different layers and the second coil patterns formed on different layers do not necessarily have the same coil cross section. However, if the coil sections of the first coil patterns formed in different layers and / or the second coil patterns formed in different layers are different, parasitic capacitance can be further suppressed. In the embodiment shown in FIG. 2, the first coil pattern Lhs1b (Lhs2b) formed in the seventh layer and the first coil pattern Lhs1d (Lhs2d) formed in the ninth layer are at least 1 / The two turns do not overlap, and the coil cross section is different.

  On the other hand, it is possible to reduce the size by simplifying the configuration related to the first coil pattern and the second coil pattern depending on the required characteristics. FIG. 4 shows an example in which only the spiral coil and the grounded capacitance electrode are extracted. In the embodiment shown in FIG. 4A, the sixth and seventh coil patterns of the embodiment shown in FIG. 2 are omitted, and the first coil pattern and the second coil pattern are each one. It is embodiment comprised by these. The embodiment shown in FIG. 4B omits the sixth layer coil pattern of the embodiment shown in FIG. 2, and uses two first coil patterns and one second coil pattern. It is the embodiment comprised. What is necessary is just to change the shape of the capacity | capacitance electrode formed in an upper layer rather than a coil pattern according to the connection method with the coil pattern formed in the 8th layer.

  In the embodiment shown in FIG. 2 or FIG. 4, the magnitude relation of the coil cross section is in the order of small, large, small, large from the grounded capacitance side, but can also be in the order of large, small, large, small. However, in the spiral coil, the portion closest to the capacitive electrode forming the grounded capacitive element connected in series to the inductance element is the first coil having a small coil cross section as in the embodiment shown in FIG. 2 or FIG. A pattern is preferred. In the embodiment shown in FIG. 2 or FIG. 4, the capacitive electrodes Chs2 and Chs4 forming the grounded capacitive element connected in series with the inductance element have the second coil cross section (perpendicular to the laminating direction) when viewed from the laminating direction of the laminated substrate. The area occupied by the high-pass filter in the direction perpendicular to the stacking direction is reduced by being arranged so as to overlap with the maximum occupied area of the spiral coil in the direction. In this case, in order to suppress a change in impedance caused by facing the capacitive electrodes Chs2 and Chs4 forming the grounded capacitive element and the ground electrode formed thereunder, a grounded capacitive element connected in series to the inductance element is formed. It is preferable that the coil pattern closest to the capacitor electrode to be smaller is smaller. The capacitance electrodes Chs2 and Chs4 and the second coil cross section need only partially overlap each other, but it is more preferable that the entire capacitance electrodes Chs2 and Chs4 overlap the second coil cross section as in the example of FIG.

  In the case of a high-pass filter configured using a plurality of inductance elements, the configuration related to the above-described inductance element and the configuration related to the capacitive element shown below may be provided in at least one portion related to the inductance element. More preferably, the portion related to the inductance element is provided.

In the embodiment shown in FIG. 2, the plurality of capacitive electrodes forming the capacitive elements C41, C43 and C45 connected in series in the signal path between the input / output terminals T _in / T _out are arranged from the sixth layer to the ninth layer. It is formed in a dielectric layer (second layer to fifth layer) different from the formed spiral coil. Here, the coil patterns Lhs1a and Lhs2a that are closest to the plurality of capacitive electrodes when viewed from the stacking direction of the multilayer substrate among the coil patterns that form the spiral coil are the leftmost pattern portion, the rightmost pattern portion in the sixth layer, and The pattern portion on the lower end side does not overlap the capacitive electrodes Chs3f and Chs3g that are closest to the spiral coil when viewed from the stacking direction of the multilayer substrate among the plurality of capacitive electrodes. With this configuration, the parasitic capacitance between the coil pattern of the inductance element and the electrode of the capacitive element is suppressed. That is, each of the three orthogonal linear pattern portions of the coil pattern Lhs1a does not overlap with the capacitive electrode Chs3f over the entire linear portion. Although such a configuration is more preferable, if the coil portion of at least 1/2 turn of the coil pattern Lhs1a is not overlapped with the capacitance electrode Chs3f, the effect of suppressing the parasitic capacitance is exhibited. In the embodiment shown in FIG. 2, even in the portion of the capacitive electrode Chs3f that overlaps the coil pattern Lhs1a, the width in the extending direction (vertical direction in the drawing) of the coil pattern Lhs1a related to the overlapping portion is larger than the width of other portions. To reduce the parasitic capacitance. This configuration is the same in the relationship between the capacitive electrode Chs3g and the coil pattern Lhs2a.

Further, _{in the} embodiment shown in FIG. 2 in which one end is connected to the signal path between the input / output terminals T _in / T _out and the other end is grounded, the coil pattern and the inductance constituting the inductance element L41 are provided. The coil pattern constituting the element L42 is formed on the same dielectric layer (sixth to ninth layers). Capacitance electrodes forming the grounded capacitive elements C42 and C44 are also formed in the same tenth layer. Capacitance electrodes forming the capacitive elements C41 and C45 connected to the signal path between the input / output terminals T _in / T _out are also formed on the same dielectric layer (second layer to fifth layer). In order to increase the bandwidth and increase the attenuation by increasing the number of stages of the circuits constituting the high-pass filter, the spiral coils of the inductance elements L41 and L42 are arranged in parallel in the direction perpendicular to the stacking direction using the above configuration. As a result, the high-pass filter can be miniaturized and the parasitic capacitance between the stages can be reduced. Here, the parallel arrangement means that the spiral coils of the inductance elements are arranged close to each other and arranged in a line.

  The winding direction of the coil of each inductance element constituting the high-pass filter is not particularly limited, but in the embodiment shown in FIG. 2, the magnetic field generation direction of the spiral coil of each inductance element is the adjacent inductance element. L41 and L42 are in opposite directions. It is also possible to attenuate a desired band by adjoining the spiral coils of the inductance elements and magnetically coupling the inductance elements.

  In the embodiment shown in FIG. 2, in adjacent inductance elements, the first coil patterns (Lhs1d and Lhs2d, Lhs1b and Lhs2b) and the second coil patterns (Lhs1c and Lhs2c) arranged on the same dielectric layer are arranged. Lhs1a and Lhs2a) are formed substantially symmetrical with respect to the center line therebetween. As a result, the reflection characteristics at the input and output are symmetric, and the design is facilitated. Here, “substantially line symmetric” is not intended to be completely line symmetric, but is intended to allow deviations from symmetry due to connection portions between patterns that do not affect coil characteristics and manufacturing variations. .

  FIG. 5 shows another embodiment of the high-pass filter according to the present invention. The high-pass filter of this embodiment corresponds to the equivalent circuit of FIG. Since the structure concerning the 1st layer-the 9th layer of FIG. 5 is the same as that of embodiment shown in FIG. 2, description is abbreviate | omitted. In the embodiment shown in FIG. 5, similarly to the embodiment shown in FIG. 2, other capacitive elements C42 and C44 respectively connected in series to the inductance elements L41 and L42 are provided, and the capacitive electrodes Chs2 and Chs4 that form the capacitive elements are provided. The size is reduced by being arranged so as to overlap with the second coil cross section related to Lhs1c and Lhs2c when viewed from the lamination direction of the laminated substrate. However, the configuration related to the capacitance electrodes Chs2 and Chs4 is different from the embodiment shown in FIG. That is, in the embodiment shown in FIG. 5, a ground electrode is further arranged in the tenth layer between the spiral coils (Lhs1a to Lhs1d, Lhs2a to Lhs2d) and the capacitive electrodes Chs2 and Chs4. The parasitic capacitance formed between the coil pattern and the capacitance electrode forming the ground capacitance is reduced. A high-pass filter was formed on the 10th layer so as to overlap the spiral coil when viewed from the stacking direction except for the periphery of the via electrode for connecting the coil pattern of the 9th layer and the capacitor electrode of the 11th layer. A ground electrode is formed over the entire dielectric layer portion. A ground electrode is also formed over the entire dielectric layer portion on which the high-pass filter is formed in the twelfth layer. Since the capacitance electrodes Chs2 and Chs4 are sandwiched between the ground electrodes and a large capacitance can be formed, the degree of freedom of capacitance formation is increased. Note that the ground electrode formed in the twelfth layer may be omitted.

  The high-pass filter according to the present invention may be configured as a single high-pass filter, but may be used in a high-frequency circuit that requires a high-pass filter. The high-frequency circuit includes, for example, a laminated body in which electrode patterns are formed on a plurality of dielectric layers, and an element such as a semiconductor element or an inductor mounted on the surface of the laminated body, and is used in a communication device. A high-frequency module having a high-frequency circuit. The high-pass filter according to the present invention is used as a high-pass filter included in the high-frequency circuit.

  Examples of the high-frequency module include an antenna switch module that switches between transmission and reception of wireless communication such as a wireless LAN, and a composite module that integrates an antenna switch module and a high-frequency amplifier module. A typical configuration of such a high-frequency module includes at least one antenna terminal connected to an antenna, at least one transmission terminal to which a transmission signal is input, at least one reception terminal to which a reception signal is output, and the antenna terminal. And at least one switch circuit that switches connection between the transmission terminal and the reception terminal.

  FIG. 6 shows a high-frequency switch module used for switching between transmission and reception of two communication systems having different frequency bands as an example of the high-frequency module according to the present invention. A 2.4 GHz band and a 5 GHz band wireless LAN are taken as examples of the communication system. Antenna terminal Ant, transmission terminals TX5 and TX2.4 and reception terminals RX5 and RX2.4 of each communication system, and transmission / reception paths connected to the antenna terminal Ant are transmission paths connected to transmission terminals TX5 and TX2.4. And a high-frequency switch circuit SPDT for switching to the reception path connected to the reception terminals RX5 and RX2.4. The high-pass filter according to the present invention has a frequency band of two communication systems of 2.4 GHz band and 5 GHz band as a pass band in at least one of the transmission / reception path and the reception path through which signals of the two communication systems flow. Is arranged. On the switching terminal side of the high-frequency switch circuit SPDT, a transmission-side branching circuit DIP1 and a reception-side branching circuit DIP2 are connected, and the branching circuit branches the transmission path and reception path into paths for different communication systems. Is done. High-frequency amplifier circuits PA1 and PA2 are connected between the transmission-side branching circuit DIP1 and the transmission terminals TX5 and TX2.4 for each communication band. Further, between the high-frequency amplifier circuits PA1 and PA2 and the transmission terminals TX5 and TX2.4, Between them, band-pass filters BPF1 and BPF3 are connected. On the other hand, a low noise amplifier LNA for amplifying the received signals of the two communication systems is connected between the high frequency switch circuit SPDT and the receiving side branching circuit DIP2. Band-pass filters BPF2 and BPF4 are connected between the receiving-side branching circuit DIP2 and the receiving terminals RX5 and RX2.4. Note that the transmission terminal and the reception terminal in the 5 GHz band are connected to a balun and are balanced terminals. However, portions other than the configuration related to the arrangement of the high-pass filter, such as a high-frequency amplifier circuit, a band-pass filter, and a balun, may be omitted or changed as appropriate according to the required functions and characteristics.

  The equivalent circuit of the high-pass filter used in the high-frequency module shown in FIG. 6 is not particularly limited, but the high-pass filter HPF1 provided between the antenna terminal Ant and the high-frequency switch circuit SPDT is shown in FIG. The circuit is more suitable, and protects the high-frequency module and the IC provided in the subsequent stage from the ESD voltage and attenuates unnecessary signals outside the communication band. The high-pass filter HPF2 provided between the high-frequency switch circuit SPDT and the low-noise amplifier LNA is more preferably the circuit shown in FIG. 1D, and attenuates unnecessary signals outside the reception band. Since the high-pass filter arranged in the signal path through which the signals of the two communication systems having different frequency bands flow requires a wide band characteristic, the high-pass filter according to the present invention that is advantageous for widening the band can be preferably used. The configuration of the high-pass filter according to the present invention is not limited to the case where there are two communication systems, and can be applied to a high-frequency module that handles two or more communication systems having different frequency bands. In other words, the high-pass filter according to the present invention may be used in which at least one of the transmission / reception path and the reception path through which signals of two or more communication systems flow has a frequency band of two or more communication systems as a pass band.

  The high pass filter HPF1 and the high pass filter HPF2 shown in FIG. 6 are preferably formed on the same dielectric layer in the multilayer substrate. That is, the high-pass filters HPF1 and HPF2 according to the present invention are arranged in the transmission / reception path and the reception path through which signals of the two communication systems flow, and each coil pattern of the high-pass filter HPF1 arranged in the transmission / reception path and the high-pass arranged in the reception path Each coil pattern of the filter HPF2 is preferably formed on the same dielectric layer of the multilayer substrate. The high-pass filter according to the present invention forms a coil pattern in a plurality of dielectric layers, but can reduce the total number of dielectrics necessary for forming a plurality of high-pass filters to the minimum necessary. Such a configuration contributes to the miniaturization of a high-frequency module incorporating a plurality of high-pass filters.

  The high-pass filter according to the present invention can be widely applied not only to the high-frequency switch module but also to other high-frequency modules. In addition, the high-pass filter and the high-frequency module using the same according to the present invention can be applied to various communication devices. Especially applicable to mobile phones, Bluetooth (registered trademark) communication devices, wireless LAN communication devices (802.11a / b / g / n), WIMAX (802.16e), IEEE802.20 (I-burst), etc. that handle high frequencies. It is possible. For example, it corresponds to the high-frequency front-end module or IEEE802.11n standard that can share two communication systems of 2.4GHz band wireless LAN (IEEE802.11b and / or IEEE802.11g) and 5GHz band wireless LAN (IEEE802.11a) It is possible to realize a small multiband communication device equipped with the high-frequency front-end module that can be used.

  The communication system is not limited to the frequency band and communication standard described above, and can be used for various communication systems. In addition to the two communication systems, for example, by adopting a mode in which the branching circuit is further branched in multiple stages, it is possible to cope with a larger number of communication systems.

  Examples of multiband communication devices include wireless communication devices typified by mobile phones, personal computers (PCs), PC peripheral devices such as printers and hard disks, broadband routers, fax machines, refrigerators, standard televisions (SDTV), and high-definition televisions. (HDTV), camera, video, etc. can be deployed in home electronic devices.

  The laminated high-pass filter and the high-frequency module according to the present invention are made of a ceramic dielectric material LTCC (Low Temperature Co-fired Ceramics) that can be sintered at a low temperature of 1000 ° C. or less, for example, and have a thickness of 10 μm to 200 μm. In addition, a conductive paste such as Ag or Cu having a low resistivity is printed to form a predetermined electrode pattern, and a plurality of green sheets are appropriately integrally laminated and sintered. As the dielectric material, for example, Al, Si, Sr as a main component, Ti, Bi, Cu, Mn, Na, K as a subcomponent, Al, Si, Sr as a main component, Ca, Pb, A material containing Na and K as subcomponents, a material containing Al, Mg, Si, and Gd, and a material containing Al, Si, Zr, and Mg are used, and a material having a dielectric constant of about 5 to 15 is used.

In addition to the ceramic dielectric material, a composite material formed by mixing a resin material or a resin and ceramic dielectric powder can be used for the dielectric layer constituting the laminated substrate. Further, the ceramic laminated substrate may be manufactured using HTCC (high temperature co-fired ceramic) technology. That is, the ceramic laminated substrate may be configured using a dielectric material mainly composed of Al ₂ O ₃ and a metal conductor that can be sintered at a high temperature such as tungsten or molybdenum. When configuring a high-pass filter with a ceramic multilayer substrate, pattern electrodes for inductance elements, capacitor elements, terminals / wirings, and ground electrodes are appropriately configured in each layer, and via conductors are formed between the layers. Thus, a desired circuit is configured.

It is an example of the equivalent circuit of the high pass filter which concerns on this invention. It is a lamination pattern figure showing an embodiment of a high pass filter concerning the present invention. It is a figure which shows the positional relationship of a coil pattern, and a coil cross section. It is a lamination pattern figure showing a coil pattern of other embodiments of a high pass filter concerning the present invention. It is a lamination pattern figure showing another embodiment of a high pass filter concerning the present invention. It is a circuit block diagram showing an embodiment of a high frequency module according to the present invention. It is a circuit diagram which shows the conventional high frequency module. It is a lamination pattern figure of the conventional high frequency module.

Explanation of symbols

T _in , T _out : Input / output terminals C11, C21, C22, C31, C32, C41 to C45: Capacitance elements L11, L21, L31, L32, L41, L42: Inductance elements Chs1a, Chs1b: Capacitance electrodes Chs2: Capacitance electrodes Chs3a , Chs3c, Chs3e, Chs3g: capacitive electrode Chs4: capacitive electrode Chs5a, Chs5b: capacitive electrode GND: ground electrode Lhs1b, Lhs1d, Lhs2b, Lhs2d: first coil pattern Lhs1a, Lhs1c, Lhs2 : Antenna terminals DIP1, DIP2: Demultiplexing circuit HPF1, HPF2: High-pass filter LNA: Low noise amplifier PA1, PA2: High frequency amplifier circuit SPDT: High frequency switch circuit BAL1, BAL2: Run BPF1~4: a band-pass filter

Claims (11)

A pair of input and output terminals;
A capacitive element connected in series in the signal path between the input and output terminals;
An inductance element having one end connected to the signal path between the input and output terminals and the other end grounded;
A high-pass filter configured using a multilayer substrate formed by laminating a plurality of dielectric layers,
The inductance element is formed in a dielectric layer different from the first coil pattern and the first coil pattern that is formed in the dielectric layer and constitutes a coil portion of more than 1/2 turn, and is formed in 1/2 turn. A second coil pattern constituting a super coil portion,
The first and second coil patterns have one end connected in series to form a spiral coil,
The first coil cross section formed when the first coil pattern is extended to one turn is smaller than the second coil cross section formed when the second coil pattern is extended to one turn. ,
The high-pass filter, wherein the first coil cross section does not protrude from the second coil cross section when viewed from the stacking direction of the multilayer substrate. A plurality of at least one of the first coil pattern and the second coil pattern;
In the stacking direction of the stacked substrate, the first coil pattern and the second coil pattern are alternately arranged on different dielectric layers, and are connected in series to form a spiral coil. The high-pass filter according to claim 1, wherein: Having another capacitive element connected in series to the inductance element;
The capacitive electrode forming the other capacitive element is disposed so as to overlap the second coil cross section when viewed from the stacking direction of the stacked substrate,
3. The high-pass filter according to claim 1, wherein a portion of the spiral coil that is closest to the capacitive electrode is the first coil pattern. Having another capacitive element connected in series to the inductance element;
The capacitive electrode forming the other capacitive element is disposed so as to overlap the second coil cross section when viewed from the stacking direction of the stacked substrate,
The high pass filter according to claim 1, wherein a ground electrode is disposed between the spiral coil and the capacitive electrode. A plurality of capacitive electrodes forming a capacitive element connected in series in a signal path between the input / output terminals are formed on a dielectric layer different from the spiral coil,
Of the coil patterns forming the spiral coil, the coil pattern closest to the plurality of capacitive electrodes when viewed from the stacking direction of the multilayer substrate is such that at least a half turn coil portion of the plurality of capacitive electrodes 5. The high-pass filter according to claim 1, wherein the high-pass filter does not overlap with a capacitive electrode closest to the spiral coil when viewed from the stacking direction of the multilayer substrate. One end is connected to the signal path between the input and output terminals, the other end is grounded, and a plurality of the inductance elements are provided,
The high-pass filter according to claim 1, wherein the spiral coils of the inductance elements are arranged side by side in a direction perpendicular to the stacking direction.   The high-pass filter according to claim 6, wherein the magnetic field generation direction of the spiral coil of each inductance element is opposite between adjacent inductance elements.   In the adjacent inductance elements, the first coil patterns and the second coil patterns arranged on the same dielectric layer are substantially symmetrical with respect to the center line therebetween. 8. The high-pass filter according to claim 7, wherein A high-frequency module used for switching between transmission and reception of two or more communication systems having different frequency bands,
An antenna terminal;
A transmission terminal and a reception terminal of each communication system;
A high-frequency switch circuit that switches a transmission / reception path connected to the antenna terminal to a transmission path connected to the transmission terminal and a reception path connected to the reception terminal;
The high-pass filter according to any one of claims 1 to 8, wherein a frequency band of the two or more communication systems is a pass band in at least one of the transmission / reception path and the reception path through which signals of the two or more communication systems flow. A high-frequency module characterized in that is arranged. The high-pass filter according to any one of claims 1 to 8 is disposed in the transmission / reception path and the reception path through which signals of the two or more communication systems flow.
The coil patterns of the high-pass filter arranged in the transmission / reception path and the coil patterns of the high-pass filter arranged in the reception path are formed on the same dielectric layer of the multilayer substrate. High frequency module.   A communication device using the high-frequency module according to claim 9 or 10.

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