JP2010136288A - Band pass filter, radio frequency component, and communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a band pass filter of a lamination type which saves its surface area, a radio frequency component using the filter, and a communication device using the component. <P>SOLUTION: In the band pass filter of a lamination type, electrode patterns lp1, lp2 forming a resonance line and electrode patterns cp1, cp2 forming a grounding capacity are made on respectively different dielectric layers. The electrode patterns lp1, lp2 forming the resonance line are arranged so as to be electromagnetically coupled with each other and to be at least partially overlapped with each other when viewed in a lamination direction. Grounding electrodes are arranged so as to sandwich the electrode patterns lp1, lp2 forming the resonance line in the lamination direction. The electrode patterns forming the grounding capacity are arranged between the grounding electrodes and the electrode patterns lp1, lp2 forming the resonance line in the lamination direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bandpass filter used for signal transmission such as wireless transmission such as a cellular phone and a wireless LAN, and a high-frequency component and a communication device using the same.

  In communication equipment, bandpass filters play an important role. While passing only a specific frequency band with low loss, it works to prevent unnecessary high-frequency and low-frequency noise from passing. Along with the miniaturization of communication devices used in portable radio communication systems and the like, many band-pass filters that are advantageous for miniaturization are used.

  As a first conventional example, the structure of a multilayer bandpass filter disclosed in Patent Document 1 is shown in FIGS. FIG. 7 is an equivalent circuit diagram of a band-pass filter of the first conventional example, and FIG. 8 is an electrode pattern diagram (hereinafter abbreviated as “lamination diagram”) of each layer when it is composed of a laminate. In this multilayer bandpass filter, as shown in FIG. 7, single-sided short-circuited strip resonator electrodes 23a, 23b, and 23c are arranged in parallel on the same sheet, and the short-circuited sides of the resonator electrodes are staggered in different directions. ing. Wavelength shortening electrodes 22a, 22b, and 22c are disposed on the sheet different from the sheet on which the resonator electrode is disposed, at corresponding positions on the side opposite to the short-circuit side of the resonator electrode. . A jumper capacitor electrode 28 is disposed on a sheet different from the sheet on which the three resonator electrodes are disposed. Further, the resonator electrodes on the input / output side of the resonator electrodes are capacitively coupled by the interlaced capacitive electrodes.

  FIG. 9 shows a laminated structure of an LC bandpass filter disclosed in Patent Document 2 as a second conventional example. In such an LC band-pass filter, the resonance line and the capacitor electrode are arranged so as to be vertically stacked in the stacking direction. These resonant lines and capacitive electrodes are connected via side electrodes formed on the side surfaces of the ceramic laminate.

JP 2006-166136 A (FIGS. 1 and 4) Japanese Laid-Open Patent Publication No. 11-97963 (Fig. 1)

  These band-pass filters are used alone, but are often built in high-frequency components such as a high-frequency switch module. Due to the recent miniaturization and thinning of mobile phones and mobile terminals, high-frequency components are required to be further miniaturized and highly integrated, and the band-pass filter is also required to be miniaturized.

  In response to such a demand, the band-pass filter of the first conventional example has a problem that the occupied area of the band-pass filter increases because a plurality of resonant lines are arranged in parallel on the same layer, It was disadvantageous for downsizing.

  In the second conventional example, the resonance line and the capacitor electrode are connected via the side electrode. However, in order to integrate the bandpass filter inside the high-frequency component, these connections are made via the through hole. Need to do. When connecting through the through holes, the through holes are respectively installed between the two resonance lines in FIG. 7 and the capacitor electrode in the lower layer, and a new installation area of the through holes is required. In addition, since the distance between the two resonant lines and the ground electrode is greatly different, the impedance on the input side and the output side tends to be unbalanced especially when the bandpass filter is made thin, and matching is difficult. It was.

  Accordingly, an object of the present invention is to provide a multilayer bandpass filter capable of saving area, and a high-frequency component and a communication device using the same.

  The band-pass filter of the present invention includes a band in which first and second LC parallel resonant circuits configured using a resonant line and a grounded capacitor are formed in a multilayer body formed by laminating a plurality of dielectric layers. In the pass filter, an electrode pattern constituting a resonant line of the first and second LC parallel resonant circuits and an electrode pattern constituting a grounded capacitor are formed on different dielectric layers, respectively, The electrode patterns constituting the resonant line of the second LC parallel resonant circuit are arranged so that at least a part thereof overlaps each other when viewed from the stacking direction so as to be electromagnetically coupled to each other, and the first and second LCs A first ground electrode is provided on the electrode pattern side constituting the resonance line of the first LC parallel resonance circuit so that the electrode pattern constituting the resonance line of the parallel resonance circuit is sandwiched in the stacking direction. However, a second ground electrode is arranged on the electrode pattern side constituting the resonance line of the second LC parallel resonant circuit, and the stacking direction, the first ground electrode and the first LC parallel resonant circuit are arranged. The electrode pattern of the ground capacitance is arranged between the electrode pattern constituting the resonance line of the first and the second ground electrode and the electrode pattern constituting the resonance line of the second LC parallel resonance circuit. It is characterized by. With such a structure, the resonance lines and the grounding capacitors constituting the plurality of resonators of the bandpass filter are arranged at positions overlapping each other when viewed from the stacking direction, so that the area occupied by the bandpass filter is reduced. In addition, since the ground capacitance is arranged on the upper side and the lower side of the resonance line, the through-holes connecting each resonance line and the corresponding ground capacitance are also distributed on the upper and lower layers of the resonance line. Be placed. Therefore, the area required for the arrangement of the through holes can be reduced. Furthermore, the area where the resonance line and the ground electrode directly face each other is reduced by disposing the capacitor electrode pattern constituting the ground capacitance between the resonance line and the ground electrode. Since this configuration suppresses the parasitic capacitance between the resonant line and the ground electrode, it is also effective in improving the insertion loss.

  Further, between the one input / output terminal provided in the band pass filter and the resonance line of the first LC parallel resonant circuit, and the other input / output terminal provided in the band pass filter and the second LC parallel resonant circuit. Input / output capacitors are connected to each of the resonance lines, the electrode patterns forming the input / output capacitors, the electrode patterns constituting the resonance lines of the first and second LC parallel resonance circuits, and the It is preferable that the grounding capacitor electrode patterns are arranged so that at least a part thereof overlaps each other when viewed from the stacking direction. According to such a configuration, an increase in the area occupied by the bandpass filter can be suppressed even when the input / output capacitance is formed.

  Further, in the band pass filter, in the stacking direction, an interval between the first ground electrode and an electrode pattern constituting a resonance line of the first LC parallel resonant circuit, and the second ground electrode and the second The interval between the electrode pattern constituting the resonance line of the LC parallel resonance circuit and the electrode pattern constituting the resonance line of the first LC parallel resonance circuit constitutes the resonance line of the second LC parallel resonance circuit. It is preferable that the distance is smaller than the distance from the electrode pattern. With this configuration, it is possible to reduce the size of the bandpass filter while suppressing parasitic capacitance.

  Furthermore, in the band pass filter, a first transmission line having one end connected to an electrode pattern constituting a resonance line of the first LC parallel resonance circuit, and a resonance line of the second LC parallel resonance circuit at one end A second transmission line connected to an electrode pattern constituting the first dielectric line, wherein the first and second transmission lines are formed with an electrode pattern constituting a resonance line of the first LC parallel resonant circuit. The other end of the first and second transmission lines is formed on the dielectric layer between the body layer and the dielectric layer on which the electrode pattern constituting the resonance line of the second LC parallel resonance circuit is formed. Are preferably grounded through the same via electrode. With such a structure, the resonant line is grounded via a parasitic inductance component, which is effective for widening the bandpass filter. In addition, since the inductance balance including the parasitic inductance is excellent among the plurality of resonance circuits, design such as matching is facilitated.

  In the bandpass filter, one end of the electrode pattern constituting the resonance line of the first LC parallel resonance circuit and one end of the electrode pattern constituting the resonance line of the second LC parallel resonance circuit are via electrodes. And a dielectric layer formed with an electrode pattern forming the resonance line of the first LC parallel resonance circuit and a dielectric layer formed with an electrode pattern forming the resonance line of the second LC parallel resonance circuit It is also preferable that the via electrode is grounded via a transmission line formed in a dielectric layer different from the body layer. Even with such a configuration, the resonance line is grounded via the parasitic inductance component, which is effective for widening the bandpass filter.

  The high-frequency component of the present invention is a high-frequency circuit configured for a high-frequency circuit used in a communication device, using a laminated body in which an electrode pattern is formed on a plurality of dielectric layers, and an element mounted on the surface of the laminated body. The high-frequency circuit includes a band-pass filter, and the band-pass filter according to the present invention is used as the band-pass filter.

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

  According to the present invention, it is possible to realize a laminated band-pass filter with a small occupation area. It also contributes to the miniaturization of high-frequency modules using bandpass filters.

  Embodiments of the present invention will be described below in detail with reference to the drawings, but the present invention is not limited thereto. FIG. 1 is an equivalent circuit of an embodiment of a bandpass filter according to the present invention. The bandpass filter shown in FIG. 1 is a multilayer bandpass filter in which two resonance lines lp1 and lp2 are electromagnetically coupled. lp1 and cp1 and lp2 and cp2 constitute an LC parallel resonance circuit, respectively. c1 and c2 are capacitors arranged in series in the input / output section of the bandpass filter, and have a DC cut function and an impedance matching function for cutting off a direct current.

  FIG. 2 is an exploded perspective view of a laminated structure in an embodiment of the bandpass filter according to the present invention. In the figure, small squares indicate through holes, and broken lines connecting the squares in the stacking direction indicate connection between the through holes. Illustration of the connection of the ground through hole is omitted for convenience. Further, the electrode patterns corresponding to the resonance line and the capacitance of the bandpass filter shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG. In the band-pass filter according to the present invention, the first and second LC parallel resonance circuits configured using the resonance line and the grounded capacitor are formed in the multilayer body formed by laminating a plurality of dielectric layers. Yes. The band-pass filter shown in FIG. 2 is configured using ten dielectric layers (dielectric sheets). An electrode pattern is printed on each dielectric layer with a conductive paste. The through holes for electrically connecting the electrode patterns of the respective dielectric layers are also filled with a conductive paste to form via electrodes. Each dielectric layer is laminated and integrated.

  As shown in FIG. 2, the electrode patterns constituting the resonance line lp1 of the first resonance circuit and the resonance line lp2 of the second LC parallel resonance circuit and the electrode patterns constituting the grounding capacitors cp1 and cp2 are different from each other. Layers (seventh layer, fourth layer, ninth layer, second layer) are formed. The electrode patterns lp1 and lp2 constituting the resonance lines of the first and second LC parallel resonance circuits are band-like electrodes having a shape in which one end of the straight line portion is bent. The electrode patterns lp1 and lp2 are disposed so as to overlap each other when viewed from the stacking direction so as to be electromagnetically coupled to each other through the dielectric layer. In the embodiment shown in FIG. 2, the electrode patterns lp1 and lp2 are arranged so as to overlap each other. However, if the electrode patterns lp1 and lp2 are arranged so that at least some of them overlap each other, for example, so as to be electromagnetically coupled in a straight portion Good.

  A first ground electrode e1 is arranged on the tenth layer on the electrode pattern lp1 side and a second ground electrode e2 is arranged on the first layer on the electrode pattern lp2 side so as to sandwich the electrode patterns lp1 and lp2 in the stacking direction. ing. Furthermore, electrode patterns cp1 and cp2 of ground capacitance are arranged in the stacking direction, between the first ground electrode e1 and the electrode pattern lp1, and between the second ground electrode e2 and the electrode pattern lp2, respectively. . The electrode pattern cp1 forms a ground capacitance with the ground electrode e1, and the electrode pattern cp2 forms a ground capacitance with the ground electrode e1. The arrangement of the electrode patterns cp1 and cp2 prevents at least a part of the electrode patterns lp1 and lp2 from directly facing the first ground electrode e1 and the second ground electrode e2, respectively, thereby suppressing parasitic capacitance. Yes.

  In addition, the electrode patterns lp1 and lp2 of the resonance lines constituting the plurality of resonators of the bandpass filter and the electrode patterns cp1 and cp2 of the grounding capacitor are arranged at positions where at least a part thereof overlaps when viewed from the stacking direction. The area occupied by the pass filter is reduced. Furthermore, by arranging the electrode pattern cp2 of the ground capacitance on the upper side of the resonance line lp2 and the electrode pattern cp1 of the ground capacitance on the lower side of the resonance line lp1, a gap between one end of each resonance line and the corresponding ground capacitance is provided. The through holes to be connected are also distributed and arranged on the upper layer side and the lower layer side of the resonance lines lp1 and lp2. As a result, the area necessary for arranging the through holes can be reduced. In the embodiment shown in FIG. 2, a through hole that connects the electrode pattern lp1 of the resonance line and the electrode pattern cp1 of the ground capacitance, and a through hole that connects the electrode pattern lp2 of the resonance line and the electrode pattern cp2 of the ground capacitance are formed. By arranging so as to overlap, the area required for through-hole arrangement is particularly reduced.

  In the embodiment shown in FIG. 2, in the stacking direction, the distance between the first ground electrode e1 and the electrode pattern lp1 constituting the resonance line of the first LC parallel resonant circuit (hereinafter also referred to as the distance d1), and the second The distance between the ground electrode e2 and the electrode pattern lp2 constituting the resonance line of the second LC parallel resonance circuit (hereinafter also referred to as the distance d2) is the electrode pattern lp1 constituting the resonance line of the first LC parallel resonance circuit And an interval between the electrode pattern lp2 constituting the resonance line of the second LC parallel resonance circuit (hereinafter also referred to as an interval d0). Although the configuration related to these intervals is not limited to the configuration shown in FIG. 2, the electrode pattern lp1 and the electrode pattern lp2 formed with a predetermined width are opposed to each other in the stacking direction, so that electromagnetic coupling is strong. . Therefore, it is preferable that the electrode pattern lp1 and the electrode pattern lp2 have a certain distance. Therefore, it is preferable that the distances d1 and d2 be smaller than the distance d0 so that the dimension in the stacking direction does not increase. If d1 and d2 are simply reduced, the parasitic capacitance formed between the electrode patterns lp1 and lp2 and the ground electrodes e1 and e2 increases. However, in the configuration shown in FIG. Because of the arrangement, parasitic capacitance is difficult to form. Therefore, in the embodiment shown in FIG. 2, a configuration in which the intervals d1 and d2 are smaller than the interval d0 is effective.

  As shown in FIG. 1, between one input / output terminal P1 of the bandpass filter and the resonance line lp1 of the first LC parallel resonance circuit, and between the other input / output terminal P2 and the second LC parallel resonance circuit. Input / output capacitors c1 and c2 are respectively connected to the resonance line lp2. The electrode pattern c1 is formed on the eighth layer between the electrode pattern cp1 of the ground capacitor and the electrode pattern lp1 constituting the resonance line, and the input / output capacitor c1 is formed between the electrode pattern cp1 of the ground capacitor. ing. The electrode pattern c1 is connected to the input / output terminal P1 through a through hole. On the other hand, the electrode pattern c2 is formed on the third layer between the electrode pattern cp2 of the ground capacitance and the electrode pattern lp2 constituting the resonance line, and the input / output capacitance c2 is formed between the electrode pattern cp2 of the ground capacitance. is doing. The electrode pattern c2 is connected to the input / output terminal P2 through a through hole.

  The electrode patterns that form the input / output capacitors c1 and c2, the electrode patterns lp1 and lp2 that form the resonance lines of the first and second LC parallel resonant circuits, and the electrode patterns cp1 and cp2 of the grounded capacitor are viewed from the stacking direction. It is arranged so that at least some of them overlap each other when viewed. That is, the electrode patterns lp1, lp2, the ground capacitor electrode patterns cp1, cp2 and the input / output capacitor electrode patterns c1, c2 constituting the resonance line are all arranged so that at least a part thereof overlaps each other when viewed from the stacking direction. Thus, the area occupied by the bandpass filter is reduced. The through hole connecting the electrode pattern forming the input / output capacitor c1 and the input / output terminal P1 and the through hole connecting the electrode pattern forming the input / output capacitor c2 and the input / output terminal P2 overlap each other. As a result, the area required for through-hole arrangement is particularly small. Note that the configuration related to the input / output capacity is not limited to the configuration shown in FIG. 2, and the configuration including the presence or absence can be changed as appropriate.

  A dielectric layer (seventh layer) on which the electrode pattern lp1 constituting the resonance line of the first LC parallel resonance circuit was formed, and an electrode pattern lp2 constituting the resonance line of the second LC parallel resonance circuit were formed. On the sixth layer, which is a dielectric layer between the dielectric layer (fourth layer), an electrode pattern le1 constituting a first transmission line having one end connected to the electrode pattern lp1 is formed. Similarly, the adjacent fifth layer located between the fourth layer and the seventh layer has one end connected to the electrode pattern lp2 constituting the resonance line of the second LC parallel resonance circuit. An electrode pattern le2 constituting one transmission line is formed. The first transmission line le1 and the second transmission line le2 are shorter than the electrode patterns lp1 and lp2, and are bent. One end side of the first transmission line le1 and the second transmission line le2 extends in a direction orthogonal to the electrode patterns lp1 and lp2, and the other end side extends in a direction parallel to the electrode patterns lp1 and lp2. Yes. The other ends of the first transmission line le1 and the second transmission line le2 are grounded through the same via electrode Ve. By doing so, the resonance line is grounded via the parasitic inductance, the flatness of the insertion loss in the band of the band pass filter is increased, and the bandwidth can be widened. Furthermore, since the electrode patterns of a plurality of resonance lines including the parasitic inductance are connected to the same ground electrode and grounded, the inductance balance is excellent. The first transmission line le1 and the first transmission line le2 have the same shape and are arranged so as to overlap in the stacking direction. The configuration of the electrode pattern related to the plurality of resonant lines up to the connection to the via electrode Ve, including the transmission line, is symmetric about the fifth dielectric layer, and is particularly excellent in the balance of inductance. Is realized. In addition, since the electrode pattern having a large capacity and the electrode pattern of the resonance line having a small area are arranged symmetrically in the stacking direction, warpage is unlikely to occur during firing of the ceramic multilayer substrate.

  The configuration for grounding the resonant line via the parasitic inductance is not limited to the configuration shown in FIG. For example, one end of the electrode pattern lp1 constituting the resonance line of the first LC parallel resonance circuit and one end of the electrode pattern lp2 constituting the resonance line of the second LC parallel resonance circuit are connected by the via electrode. The dielectric layer formed with the electrode pattern lp1 constituting the resonance line of the LC parallel resonance circuit of the second LC is different from the dielectric layer formed with the electrode pattern lp2 constituting the resonance line of the second LC parallel resonance circuit. A configuration in which a transmission line is formed in the body layer and the via electrode is grounded through the transmission line can also be used.

  FIG. 3 shows the results of evaluating the pass characteristics of the bandpass filter according to the present embodiment. A large amount of attenuation is obtained on both sides of the passband, indicating excellent characteristics as a bandpass filter. Further, the occupied area of the band pass filter can be reduced by about 50% compared to the conventional configuration in which the electrode pattern of the resonant line is arranged in parallel on one dielectric layer.

  The bandpass filter according to the present invention is not limited to the bandpass filter shown in FIG. For example, a bandpass filter may be configured with three or more resonators by further adding a resonator to the two-stage resonator shown in FIG. FIG. 4 shows an equivalent circuit of another embodiment of the bandpass filter according to the present invention. The bandpass filter shown in FIG. 4 is a stacked bandpass filter in which three resonance lines lpa1 to 3pa are electromagnetically coupled. lp1 and cp1, lp2 and cp2, and lp3 and cp3 constitute an LC parallel resonance circuit, respectively. FIG. 1 shows that a third resonance circuit composed of lp3 and cp3 is provided between a first resonance circuit composed of lp1 and cp1 and a second resonance circuit composed of lp2 and cp2. Different from the embodiment shown.

  FIG. 5 is an exploded perspective view of a laminated structure according to another embodiment shown in FIG. The electrode pattern lp3 constituting the resonance line of the third LC parallel resonance circuit is formed on the seventh layer, and the electrode pattern cp3 of the ground capacitance is formed on the thirteenth layer. The electrode pattern cp3 of the ground capacitance is sandwiched between the second ground electrode e2 and the third ground electrode e3 in the stacking direction to form a ground capacitance. Between the dielectric layer in which the transmission line le2 is formed and the dielectric layer in which the transmission line le1 is formed, a dielectric layer in which the dielectric layer in which the transmission line le3 is formed and the electrode pattern lp3 that forms the resonance line is formed. The dielectric in which the third ground electrode e3 is formed between the inserted point, the dielectric layer in which the electrode pattern cp1 of the ground capacitance is formed, and the dielectric layer in which the first ground electrode e1 is formed The embodiment is different from the embodiment shown in FIG. 2 in that the electrode pattern cp3 of the body layer and the ground capacitance is formed. The other points are the same as in the embodiment shown in FIG.

  The electrode patterns lp1 to lp3 constituting the resonance lines of the first to third LC parallel resonance circuits are arranged so that at least parts thereof overlap each other when viewed from the stacking direction so as to be electromagnetically coupled to each other. Further, the electrode patterns of the capacitors are arranged on both sides of the electrode patterns lp1 to 3 constituting the resonance line of the LC parallel resonance circuit in the stacking direction. The electrode pattern cp3 of the ground capacitance is arranged so that at least a part thereof overlaps with the electrode patterns lp1 to lp3 constituting the resonance line when viewed from the stacking direction. Note that one end side of the third transmission line le3 extends in a direction orthogonal to the electrode pattern lp3, and the other end side extends in a direction parallel to the electrode pattern lp3. The other end of the third transmission line le3 is grounded through the same via electrode Ve as the first and second transmission lines le1 and 2. With the configuration shown in FIG. 4, even when a resonance circuit is added, the occupied area of the bandpass filter can be kept small.

  The band-pass filter according to the present invention may be configured as a single band-pass filter, but may be used in a high-frequency circuit that requires a band-pass filter. For example, a high-frequency circuit having a high-frequency circuit that is used in a communication device, including a stacked body in which electrode patterns are formed on a plurality of dielectric layers, and elements such as semiconductor elements and inductors mounted on the surface of the stacked body. In the component, the band-pass filter according to the present invention is used as a band-pass filter included in the high-frequency circuit.

  Examples of the high-frequency component include an antenna switch module that switches between transmission and reception of wireless communication such as a wireless LAN, and a composite module in which the antenna switch module and the high-frequency amplifier module are integrated. Such high-frequency components include, for example, 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 from which a reception signal is output, the antenna terminal, And at least one switch circuit for switching connection with the transmission terminal or the reception terminal. FIG. 6 shows an equivalent circuit of a wireless LAN front-end module as an example of a high-frequency circuit constituting a high-frequency component. The front end module shown in FIG. 6 includes an antenna terminal Ant connected to an antenna, a transmission terminal Tx_2.4G to which a 2.4 GHz band transmission signal is input, a transmission terminal Tx_5G to which a 5 GHz band transmission signal is input, A reception terminal Rx_2.4G from which a reception signal of 2.4 GHz band is output, a reception terminal Rx_5G from which a reception signal of 5 GHz band is output, an antenna terminal Ant and transmission terminals Tx_2.4G, Tx_5G or a reception terminal Rx_2.4G, And a switch circuit SPDT for switching connection to Rx_5G. An antenna terminal Ant is connected to the common terminal of the switch circuit SPDT, and a transmission-side branching circuit DIP1 and a reception-side branching circuit DIP2 are connected to the two switching terminals, respectively. A high-frequency amplifier circuit PA1 for amplifying a 2.4 GHz band transmission signal is connected between the transmission-side branching circuit DIP1 and the transmission terminal Tx_2.4G, and between the transmission-side branching circuit DIP1 and the transmission terminal Tx_5G Is connected to a high frequency amplifier circuit PA2 for amplifying a transmission signal of 5 GHz band. Band-pass filters BPF1 and BPF2 are connected to the input sides of the high-frequency amplifier circuits PA1 and PA2, respectively, and low-pass filters LPF1 and LPF2 are connected to the output side. On the other hand, a low noise amplifier circuit LNA1 for amplifying a 2.4 GHz band received signal is connected between the receiving side demultiplexing circuit DIP2 and the receiving terminal Rx_2.4G, and the receiving side demultiplexing circuit DIP2 and the receiving terminal Rx_5G are connected. Is connected to a low noise amplifier circuit LNA2 for amplifying a received signal of 5 GHz band. Bandpass filters BPF3 and BPF4 are connected to the output sides of the low noise amplifier circuits LNA1 and LNA2, respectively. The bandpass filter according to the present invention may be used for these bandpass filters. The IC chips of the switch circuit SPDT, the high frequency amplifier circuits PA1 and PA2, and the low noise amplifier circuits LNA1 and LNA2 are mounted on a laminated substrate.

A band-pass filter in which a conductor pattern as shown in FIG. 2 is formed on a ceramic multilayer substrate is 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 has a thickness of Manufactured by printing a conductive paste such as Ag or Cu having a low resistivity on a green sheet of 10 μm to 200 μm to form a predetermined electrode pattern, laminating a plurality of green sheets appropriately, and sintering. I can do it.
As the dielectric material, for example, Al, Si, Sr as a main component, Ti, Bi, Cu, Mn, Na, K as a minor component, 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 may be 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 a band-pass filter is configured with a ceramic multilayer substrate, pattern electrodes for inductance elements, capacitive elements, wiring, and ground electrodes are appropriately configured in each layer, and via conductors are formed between the layers. A desired circuit is configured.

  The bandpass filter of the present invention can be widely applied not only to the high frequency switch module but also to other high frequency components. Further, the bandpass filter of the present invention and the high-frequency component using the same 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 supports a high-frequency front-end module or IEEE 802.11n standard that can share two communication systems of 2.4 GHz band wireless LAN (IEEE 802.11b and / or IEEE 802.11g) and 5 GHz band wireless LAN (IEEE 802.11a). It is possible to realize a small-sized multiband communication device equipped with such a high-frequency front-end module. 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 peripherals 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.

It is an equivalent circuit diagram showing an embodiment of a band pass filter concerning the present invention. It is a lamination figure in an embodiment of a band pass filter concerning the present invention. It is an attenuation characteristic figure of an embodiment of a band pass filter concerning the present invention. It is an equivalent circuit schematic which shows other embodiment of the band pass filter which concerns on this invention. It is a lamination figure in other embodiments of the band pass filter concerning the present invention. 1 is an equivalent circuit diagram of an embodiment of a high-frequency component according to the present invention. It is an equivalent circuit diagram of a conventional bandpass filter. It is an electrode pattern figure of each layer in the conventional lamination type band pass filter. It is an electrode pattern figure of each layer in the conventional lamination type band pass filter.

Explanation of symbols

lp1-3: resonant lines le1-3: transmission lines cp1-cp3, c1, c2: capacitive electrodes P1, P2: input / output terminals

Claims (7)

A bandpass filter in which first and second LC parallel resonant circuits configured using a resonant line and a grounded capacitor are formed inside a multilayer body formed by laminating a plurality of dielectric layers,
The electrode pattern constituting the resonant line of the first and second LC parallel resonant circuits and the electrode pattern constituting the grounded capacitor are formed in different dielectric layers, respectively.
The electrode patterns constituting the resonance lines of the first and second LC parallel resonance circuits are arranged so that at least a part thereof overlaps each other when viewed from the stacking direction so as to be electromagnetically coupled to each other,
A first ground is provided on the side of the electrode pattern constituting the resonance line of the first LC parallel resonance circuit so that the electrode pattern constituting the resonance line of the first and second LC parallel resonance circuit is sandwiched in the stacking direction. A second ground electrode is disposed on the electrode pattern side where the electrode forms the resonance line of the second LC parallel resonance circuit,
The stacking direction, between the first ground electrode and the electrode pattern constituting the resonance line of the first LC parallel resonance circuit, and between the second ground electrode and the resonance line of the second LC parallel resonance circuit A band-pass filter, wherein an electrode pattern of the grounded capacitance is disposed between the electrode pattern to be configured. Resonance between one input / output terminal provided in the band-pass filter and the resonance line of the first LC parallel resonant circuit, and resonance between the other input / output terminal provided in the band-pass filter and the second LC parallel resonant circuit. Input / output capacitors are connected to the tracks,
The electrode patterns forming the input / output capacitors, the electrode patterns constituting the resonance lines of the first and second LC parallel resonance circuits, and the electrode patterns of the ground capacitors are at least partially viewed from the stacking direction. The band-pass filter according to claim 1, wherein the band-pass filters are arranged so as to overlap each other.   In the stacking direction, the distance between the first ground electrode and the electrode pattern constituting the resonance line of the first LC parallel resonance circuit, and the resonance line of the second ground electrode and the second LC parallel resonance circuit Is smaller than the distance between the electrode pattern constituting the resonant line of the first LC parallel resonant circuit and the electrode pattern constituting the resonant line of the second LC parallel resonant circuit. The band-pass filter according to claim 1 or 2, wherein A first transmission line having one end connected to an electrode pattern constituting a resonance line of the first LC parallel resonance circuit;
A second transmission line connected at one end to an electrode pattern constituting a resonance line of the second LC parallel resonance circuit;
The first and second transmission lines constitute a dielectric layer on which an electrode pattern constituting the resonance line of the first LC parallel resonance circuit is formed, and a resonance line of the second LC parallel resonance circuit. Formed on the dielectric layer between the dielectric layer on which the electrode pattern is formed,
The band-pass filter according to any one of claims 1 to 3, wherein the other ends of the first and second transmission lines are grounded through the same via electrode. One end of the electrode pattern constituting the resonance line of the first LC parallel resonance circuit and one end of the electrode pattern constituting the resonance line of the second LC parallel resonance circuit are connected by a via electrode,
A dielectric layer on which an electrode pattern constituting a resonance line of the first LC parallel resonance circuit is formed, and a dielectric layer on which an electrode pattern constituting a resonance line of the second LC parallel resonance circuit is formed The band pass filter according to any one of claims 1 to 3, wherein the via electrode is grounded via a transmission line formed in a different dielectric layer. A high frequency circuit used in a communication device is a high frequency component configured by using a laminate in which electrode patterns are formed on a plurality of dielectric layers, and an element mounted on the surface of the laminate,
The high-frequency circuit has a band-pass filter;
A high-frequency component using the band-pass filter according to claim 1 as the band-pass filter.   A communication device using the high-frequency component according to claim 6.

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