JP2009153106A - Band-pass filter, high-frequency component, and communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a band-pass filter reduced in its size and loss, to provide a high-frequency component using the same, and to provide a communication apparatus. <P>SOLUTION: The band-pass filter is provided with two or more resonance lines arranged side by side in a direction orthogonal to a laminating direction in a laminate substrate formed by laminating a plurality of dielectric layers. Each resonance line has a first coil pattern portion formed in one of the dielectric layers and a second coil pattern portion formed in the dielectric layer different from that where the first coil pattern is formed. The first and second coil pattern portions are connected in series so as to be formed in a spiral shape. At least one of the first and second coil pattern portions is formed as lines in parallel in the plurality of dielectric layers. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a band-pass filter used for 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 component and a communication device 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. Along with the downsizing and high functionality of wireless devices, there is a strong demand for miniaturization while integrating many high-frequency components to high-frequency components that implement the high-frequency circuit. It is essential.

  Among such high-frequency components, a bandpass filter that selectively passes a signal in a predetermined band is an important component of the communication device. The band-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 to remove unnecessary waves existing near the outside of the pass band.

  For example, Patent Document 1 discloses a multilayer bandpass filter. In the bandpass filter described in Patent Document 1, a plurality of coil electrodes are connected to each other to form a spiral electrode, and the spiral electrode is electromagnetically coupled. With this configuration, the bandpass filter is reduced in size.

JP-A-6-53704

  However, in the band-pass filter described in Patent Document 1, since the spiral electrode itself remains long, the loss cannot be sufficiently reduced. Further, in the band-pass filter disclosed in Patent Document 1, there is a possibility that the impedance changes due to a shift in the lamination process and the filter characteristics fluctuate. That is, when the coil electrode formed on each dielectric layer is displaced in the in-plane direction, the effective inner diameter of the coil viewed from the projection direction (winding axis direction) is deviated from the design value, and the impedance changes. As described above, the multilayer band-pass filter in which the electrodes of the resonator are formed over a plurality of layers has a problem of characteristic fluctuations due to misalignment.

  Accordingly, an object of the present invention is to provide a bandpass filter that can be reduced in size and reduced in size, a high-frequency component using the bandpass filter, and a communication device. Another object of the present invention is to suppress fluctuations in filter characteristics due to misalignment in such a bandpass filter.

  The bandpass filter of the present invention is a bandpass filter comprising two or more resonant lines arranged in a direction perpendicular to the laminating direction in a laminated substrate formed by laminating a plurality of dielectric layers, Each resonance line has at least a first coil pattern portion formed in the dielectric layer and a second coil pattern portion formed in a dielectric layer different from the first coil pattern, and The first and second coil pattern portions are formed in a spiral by connecting them in series, and at least one of the first and second coil pattern portions is formed as a parallel line on a plurality of dielectric layers. It is characterized by that. According to this configuration, it is possible to reduce the size and loss of the bandpass filter.

  In the bandpass filter, it is preferable that at least one of the parallel lines has a width larger than that of the other lines of the parallel line. According to such a configuration, fluctuations in filter characteristics due to stacking deviation can be suppressed.

  Furthermore, in the bandpass filter, at least one of the parallel lines has a width larger than the other lines of the parallel line so as to spread inside the spirally formed resonant line. Is preferred.

  Furthermore, in the bandpass filter, it is preferable that a line having a width larger than that of the other line is disposed in an intermediate layer among a plurality of dielectric layers in which the resonance line is formed. Here, the intermediate layer refers to a layer excluding upper and lower layers in the stacking direction among a plurality of dielectric layers in which resonant lines are formed. If a line whose width is increased is arranged in the intermediate layer, the influence of the stacking deviation can be further suppressed.

  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.

  Furthermore, in the high frequency component, the high frequency circuit preferably includes a low noise amplifier, and the band pass filter is connected to an input side of the low noise amplifier. Since the bandpass filter has a low loss, it is preferable to arrange it on the input side of the low noise amplifier.

  Furthermore, in the high-frequency component, it is preferable that a band-pass filter configured using a linear resonant line is connected to the output side of the low-noise amplifier. Furthermore, the sensitivity of the received signal can be improved by disposing a bandpass filter that is configured using a linear resonance line and has excellent attenuation characteristics on the output side of the low noise amplifier.

  The communication device of the present invention uses the bandpass filter or the high-frequency component.

  ADVANTAGE OF THE INVENTION According to this invention, a small and low-loss band pass filter, a high frequency component using the same, and a communication apparatus can be provided.

  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 shows a conductor pattern of each layer of an embodiment of the multilayer bandpass filter according to the present invention. A bandpass filter configured on a ceramic multilayer substrate having a conductor pattern as shown in FIG. 1 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 as appropriate, and sintering. I can do it. Note that high-frequency components such as a front-end module can also be manufactured by the same ceramic multilayer substrate manufacturing process as that of the band-pass filter. 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 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.

  One embodiment of the band-pass filter according to the present invention shown in FIG. 1 is composed of 11 dielectric layers. The uppermost first layer and the lowermost eleventh layer are dielectric layers on which ground electrodes are formed. Conductor patterns for capacitive elements are mainly formed on the second to fifth layers, and conductor patterns for inductance elements are mainly formed on the sixth to tenth layers.

  FIG. 4 shows an equivalent circuit of a band-pass filter constituted by the laminate of FIG. It consists of lines lb1 and lb2 which are resonant lines, and capacitive elements cb1 to cb6. An input / output capacitor cb1 is provided between the input / output port P1 and the line lb1, a grounded capacitor cb2 is provided between the line lb1 and the ground, and similarly, an input / output capacitor cb6 is provided between the input / output port P2 and the line lb2. A grounded capacitor cb5 is connected between the line lb2 and the ground. A coupling capacitor cb3 is connected between the input / output port P1 and the line lb2, and a coupling capacitor cb4 is connected between the input / output port P2 and the line lb1.

  FIG. 4 shows an equivalent circuit of the bandpass filter shown in FIG. 1, but the bandpass filter of the present invention is not limited to this. For example, the coupling capacitors cb3 and cb4 can be omitted. In this case, the capacitor electrode patterns cb3 and cb4 shown in the fourth layer in FIG. 1 are unnecessary.

  The layers are laminated in order from the 11th layer to the 1st layer, and the laminating direction is a direction orthogonal to the paper surface of FIG. A resonance line lb1 composed of lb1a to lb1e and a resonance line lb2 composed of lb2a to lb2e are arranged side by side in a direction orthogonal to the stacking direction (in-plane direction in FIG. 1). 1 is not limited to a bandpass filter including two resonance lines, and a bandpass filter including two or more resonance lines can be configured by arranging the resonance lines side by side.

  In the embodiment shown in FIG. 1, the ends of the first coil pattern portions formed on the sixth layer and the seventh layer are connected in parallel to form a parallel line, and the eighth coil formed on the eighth to tenth layers. The end portions of the two coil pattern portions are connected in parallel to constitute a parallel line. Here, the shape of each parallel line forming the second coil pattern portion has substantially the same shape except for the width. The first coil pattern portion of the sixth layer and the seventh layer and the second coil pattern portion of the eighth to tenth layers are connected in series to form a spiral inductance element. In this embodiment, the first and second coil pattern portions are parallel lines to reduce the resistance component of the conductor, reduce the loss, and increase the Q value. Note that it is not necessary that both the first and second coil pattern portions are parallel lines, and if at least one of them is formed as a parallel line on a plurality of dielectric layers, an effect of reducing loss is exhibited. However, in order to sufficiently exhibit the effect of reducing the loss, it is more preferable that both the first and second coil pattern portions are parallel lines. The resonance line may further include a coil pattern portion in addition to the first and second coil pattern portions. In this case, it is more preferable that all the coil pattern portions are parallel lines. Further, as compared with a linear inductance element used in a general band-pass filter, it is easier to realize a larger inductance component when a spiral inductance element is formed as in the present invention. For this reason, considering the case where inductance components having the same value are formed, the size of the inductance element itself can be reduced, so that the entire band-pass filter can be miniaturized, and further, the high-frequency component combined using it can be miniaturized. Can also be planned.

  An embodiment of the bandpass filter shown in FIG. 1 will be described in detail for each layer. In the drawing, a minute square portion indicates the via conductor 1. The first layer is a ground layer in which a ground electrode is formed as a whole. The rectangular capacitive electrodes cb2a and cb5a formed on the second layer in a direction orthogonal to the stacking direction form a ground capacitance with the ground layer (GND) of the first layer. This corresponds to the capacitors cb2 and cb5 in the equivalent circuit diagram of the bandpass filter shown in FIG. The capacitive electrodes cb1a and cb6a formed on the third layer and the capacitive electrodes cb1b and cb6b formed on the fifth layer are the capacitive electrodes cb2a and cb5a formed on the second layer and the capacitance formed on the fourth layer. A capacitance is formed between the electrodes cb2b and cb5b. This corresponds to the capacitors cb1 and cb6 connected to the input / output ports P1 and P2 of the equivalent circuit diagram of the bandpass filter shown in FIG.

  In the third layer, input / output electrodes p1 and p2 connected to the input / output ports P1 and P2 are positioned symmetrically with respect to the center of the substantially rectangular region forming the bandpass filter, that is, diagonally. It extends toward the side. The input / output electrodes p1 and p2 are connected to the capacitance electrodes cb1a and cb6a, respectively, to form an integral electrode pattern.

  In the fourth layer, a capacitor electrode cb4 connected to the capacitor electrode cb2b via a connection wiring is further formed. Between the capacitor electrode cb6a formed in the third layer and the capacitor electrode cb6b formed in the fifth layer. Form a capacity. This corresponds to the coupling capacitance cb4 in the equivalent circuit diagram of the bandpass filter shown in FIG. Similarly, the capacitor electrode cb3 connected to the capacitor electrode cb5b via the connection wiring is formed on the fourth layer, and between the capacitor electrode cb1a formed in the third layer and the capacitor electrode cb1b formed in the fifth layer. Form a capacity. This corresponds to the coupling capacitor cb3 in the equivalent circuit diagram of the bandpass filter shown in FIG. Here, the connection wiring connecting the capacitance electrode cb2b and the capacitance electrode cb4 and the connection wiring connecting the capacitance electrode cb5b and the capacitance electrode cb3 are made thinner than the electrodes on both sides to be connected. Further, both end sides of the connection wiring thus thinned are overlapped with the capacitor electrodes formed in the third layer and the fifth layer when viewed from the stacking direction. In other words, the connection portion between the capacitor electrode cb2b and the capacitor electrode cb4 and the connection wiring is located inside the capacitor electrodes cb1a, cb1b, cb6a, cb6b when viewed from the stacking direction. Similarly, the connection portion between the capacitor electrode cb5b and the capacitor electrode cb3 and the connection wiring is located inside the capacitor electrodes cb1a, cb1b, cb6a, cb6b (in the electrode plane) when viewed from the stacking direction. According to such a configuration, it is possible to reduce interference with other electrodes, and it is possible to minimize capacitance fluctuation when a stacking error occurs.

  The lines of the first coil pattern portions formed in the sixth layer and the seventh layer are connected in parallel, and the lines of the second coil pattern portions formed in the eighth to tenth layers are connected in parallel. Then, the first coil pattern part formed as a parallel line on the sixth layer and the seventh layer and the second coil pattern part formed as a parallel line on the eighth to tenth layers are connected in series. A resonance line is formed as a spiral inductance element.

  Here, the parallel line will be described. FIG. 2 is a schematic diagram (perspective view) showing a connection state of the resonance line on the left side of the multilayer substrate of FIG. The end portion of the line lb1a formed in the sixth layer and the end portion of the line lb1b formed in the seventh layer are respectively connected in parallel by the via conductor 1 to form a parallel line. Such parallel lines have the same number of turns, outer shape, and inner shape. The lines lb1a and lb1b having the same electrode pattern shape and connected in parallel constitute a part of the coil pattern (first coil pattern portion).

  On the other hand, the end of the line lb1c formed in the eighth layer, the end of the line lb1d formed in the ninth layer, and the end of the line lb1e formed in the tenth layer are connected in parallel by via conductors. Form a track. Lines lb1c to lb1e having substantially the same electrode pattern shape and connected in parallel constitute another part of the coil pattern (second coil pattern part). The line lb1c formed in the eighth layer is different in line width from the lines lb1d and lb1e, but the number of turns and the outer shape are the same. Then, the first coil pattern part constituted by the lines lb1a and lb1b connected in parallel and the second coil pattern part constituted by the lines lb1c, lb1d and lb1e connected in parallel are connected in series. The resonant line is formed in a spiral shape. The right resonance line that is electromagnetically coupled to the left resonance line of the multilayer substrate in FIG. 1 is configured in the same manner.

  The substantially U-shaped (C-shaped) line of approximately 5/8 turns formed in the sixth layer constitutes a part of the rectangular resonant lines lb1 and lb2 when viewed from the stacking direction. In this embodiment, the line lb1a and the line lb2a are disposed so that their one sides face each other in parallel. The degree of coupling of the resonance lines varies depending on the interval between the sides. Along with this, the pass characteristics of the bandpass filter also change. Therefore, the design may be changed as appropriate.

  Similarly, a line of approximately 5/8 turns that forms part of the resonance lines lb1 and lb2 is also formed in the seventh layer. The line formed in the seventh layer having the same shape as the line formed in the sixth layer is disposed so as to overlap the line formed in the sixth layer. The seventh layer line and the sixth layer line are connected in parallel by via conductors.

  In the eighth layer, a substantially rectangular line of approximately 7/8 turns that forms another part of the resonant lines lb1 and lb2 is formed. In this embodiment, the widths of the lines lb1c and lb2c formed in the same dielectric layer and arranged side by side are made larger than the widths of the lines formed in other dielectric layers. This is to prevent the filter characteristics from fluctuating due to stacking deviation. Specifically, the line lb1c has a line width such that the inner side of the spiral resonance line (coil) is narrower than the other lines of the parallel line, that is, the inner side of the spiral resonance line. Has increased. Accordingly, the other lines lb1d and lb1e constituting the second coil pattern portion have the same outer shape and the same number of turns, but have different inner shapes. Similarly, the line lb2c has a larger line width so that the inside of the spiral resonance line is narrower than the other lines. Accordingly, the other lines lb2d and lb2e constituting the second coil pattern portion have the same outer shape and the same number of turns, but have different inner shapes. Further, the sides forming the outer shape of the lines lb1a and lb1b constituting the first coil pattern portion are formed so as to overlap the sides forming the outer shape of the line lb1c having a larger width. The same applies to the relationship between the lines lb2a, lb2b, and lb2c. That is, the lines of the coil pattern portions that form the spiral resonance line are formed so that the outer shape of the coil is constant as a whole, and only the shapes of the lines lb1c and lb2c inside the coil are different. Although it is possible to increase the line width so that it spreads inside and outside the coil, if it is also increased outside, the distance between the resonant lines that are electromagnetically coupled decreases, and the degree of coupling changes. As shown in FIG. 1, it is more preferable to increase the line width so as to spread inside the coil. The effect of arranging a line having a large line width will be described later.

  As shown in FIG. 1, other lines (lb1a, lb1b, lb1d, lb1e, lb2a, lb2b, lb2d, lb2e) have lines (lb1c, lb2c) having a plurality of dielectric lines on which resonant lines are formed. It arrange | positions to the intermediate | middle layer (in the case of FIG. 1, 8th layer) of a body layer (6th-10th layer). However, the present invention is not limited to this, and the width of the line arranged in another layer can be increased. Here, the intermediate layer is a layer (seventh layer to tenth layer) excluding the sixth layer at the upper end in the stacking direction and the tenth layer at the lower end among the plurality of dielectric layers (sixth layer to tenth layer) in which the resonance lines are formed. 9th layer).

  Similarly, on the ninth layer and the tenth layer, a substantially rectangular line of approximately 7/8 turns that forms another part of the resonance lines lb1 and lb2 is formed. The lines of the eighth to tenth layers are connected in parallel by via conductors. The eleventh layer is a ground layer in which a ground electrode is formed as a whole. However, the ground layer is not necessarily essential, and when omitted, the impedance of the lines arranged in the sixth to tenth layers becomes large. Accordingly, when a large impedance is required, the eleventh ground layer can be omitted.

  Each line of the first and second coil pattern portions constituting the resonance line lb1 and each line of the first and second coil pattern portions constituting the resonance line lb2 are each dielectric layer in which they are formed. In all, they face each other in parallel straight portions, and the layers are arranged with the same interval. Thereby, the coupling between the resonant lines can be enhanced. In the present embodiment, the first and second coil patterns are formed substantially point-symmetric with respect to the center point of the band-pass filter, but may be formed line-symmetrically. As a result, the coupling between the resonant lines can be changed more flexibly, and the degree of design freedom increases. In addition, the electrodes for forming each resonance line lb1, lb2, its ground capacitances cb2, cb5 and its input / output capacitances cb1, cb6 are formed separately on both sides across the center of the bandpass filter formation region, and they overlap each other Thus, the miniaturization is achieved.

  The shape of the resonant line viewed from the stacking direction is not limited to the rectangle shown in FIG. The shape can be changed as appropriate. For example, when it is desired to increase the coupling between the resonance lines, it is preferable that the resonance lines are adjacent to each other at a straight line portion. Therefore, the shape of the resonance line is preferably rectangular. The rectangle includes a rounded corner and a rounded shape as shown in FIG. In order to form the band-pass filter spatially without waste, it is preferable that the shape of the resonant line viewed from the stacking direction is rectangular. Considering the electric field distribution in the resonance line, generally, the electric field concentrates on the corner portion of the resonance line and a loss occurs. As a result, the Q of the resonant line may decrease. When the characteristic deterioration due to the Q reduction is remarkable, the resonance line is preferably formed in a circular shape.

  In the embodiment shown in FIG. 1, the lines formed in the sixth layer and the seventh layer are connected in parallel and the lines formed in the eighth to tenth layers are connected in parallel, but other configurations are possible. For example, the 10th layer may be omitted, and the parallel lines may be configured by the lines formed in the 8th and 9th layers, and the number of parallel lines in each coil pattern may be the same. It is within the scope of the technical idea of the invention to appropriately change the design according to the requirements of the inductance value and the filter characteristics necessary for the resonance line.

  Here, in the band-pass filter according to the present invention with reference to FIG. 3, among the lines forming the resonant line, by arranging a line having a line width larger than that of other lines, fluctuations in impedance due to stacking deviation are suppressed. Explain what will be done. FIG. 3A shows the line lb1b in the seventh layer and the line lb1c in the eighth layer shown in FIG. The dimension inside the coil of the substantially rectangular coil pattern portion corresponds to the inner diameter of the coil, and this dimension is important. This is because the inductance of the coil is determined by the amount of change in the amount of flux linkage of the coil with respect to a minute change in the current flowing through the coil. The dimension inside the coil indicates the inner diameter in the case of a coil having a circular shape when viewed from the coil winding axis direction, and indicates the interval between opposing sides in the coil in the case of a rectangle as shown in FIG. The area of the hatched portion inside FIG. 3A is related to the amount of change in the flux linkage.

  3 (b) shows a case where the upper and lower lines are shifted in the X direction in the laminated plane, FIG. 3 (c) shows a case where the upper and lower lines are shifted in the Y direction in the laminated plane, and FIG. The case where a track | line is shifted | deviated diagonally within a lamination surface is shown typically. As can be seen from FIGS. 3A to 3D, the air-core cross-sectional area (the effective area forming the air-core portion when projected from the stacking direction) of the hatched portion inside the wound line is the stacking deviation. It can be seen that even if there is, it is substantially unchanged. This is because the width of the line lb1c is increased so as to spread inward. By making the width of one of the parallel lines larger than that of the other parallel lines, it is possible to suppress the characteristic variation due to the stacking deviation within the range of the width difference. Of the parallel lines, two or more lines that have a width larger than other parallel lines may be used, but between the lines with a larger width, the stacking misalignment leads to a decrease in the effective area of the coil inner part. More preferably, the line whose width is increased is formed in only one layer in the stacking direction, that is, one line per one resonance line. Further, in order to prevent the air-core cross-sectional area from changing, it is preferable that the shape of the line having a large width is a substantially rectangular shape exceeding 3/4 turns. Since the line having such a shape forms a line in which the inside of the coil is substantially closed with two pairs of sides, the air-core cross-sectional area is substantially equal even when the other line is shifted in any direction in the plane (XY plane). This is because it is possible to suppress the change.

  In general, since stacking deviation often occurs in one direction, the farther from the layer on which the line having a large line width is formed, the closer to the limit for absorbing stacking shift. Therefore, if the number of stacked layers is the same, it is preferable to dispose a line having a large width in the intermediate layer with respect to stacking misalignment. From this point of view, if the number of dielectric layers forming the resonance line is odd, the width is increased to the center dielectric layer, and if it is even, one of the pair of dielectric layers located in the center is increased in width. It is more preferable to arrange the line. For the same reason, in the parallel line, it is preferable to increase the line width of the layer adjacent to the other coil pattern portion. In this way, the width of at least one of the parallel lines (in this example, the lines lb1c and lb2c) is made larger than the other lines (lb1a, lb1b, lb1d, lb1e, lb2a, lb2b, lb2d, and lb2e). As a result, it is possible to prevent fluctuations in impedance due to misalignment in the manufacturing process, and consequently fluctuations in the characteristics of the bandpass filter.

  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 multilayer body in which electrode patterns are formed on a plurality of dielectric layers, and a chip element such as a semiconductor element or an inductor mounted on the surface of the multilayer body, and has a high-frequency circuit used in a communication device A high-frequency 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 that integrates an antenna switch module and a high-frequency amplifier module. A typical configuration of such a high-frequency component 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 with the transmission terminal or the reception terminal.

  An example of a dual-band wireless LAN front-end module as an example of a high-frequency component formed by using a laminated body in which electrode patterns are formed on a plurality of dielectric layers and an element mounted on the surface of the laminated body Is shown in FIG. 5 and FIG. FIG. 5 is an equivalent circuit diagram of the front end module. The front end module shown in FIG. 5 includes an antenna terminal ANT connected to an antenna, a transmission terminal TX2 to which a 2.4 GHz band transmission signal is input, a transmission terminal TX5 to which a 5 GHz band transmission signal is input, and 2. A switch circuit that switches the connection between the reception terminal RX2 that outputs a reception signal in the 4 GHz band, the reception terminal RX5 that outputs a reception signal in the 5 GHz band, and the antenna terminal ANT and the transmission terminals TX2 and TX5 or the reception terminals RX2 and RX5. With SPDT. 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. The transmission side demultiplexing circuit DIP1 includes a high-pass filter unit HPF and a low-pass filter unit LPF, and the reception-side demultiplexing circuit DIP2 includes a high-pass filter unit HPF and a bandpass filter unit BPF4. 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 TX2, and between the transmission side branching circuit DIP1 and the transmission terminal TX5. A high frequency amplifier circuit PA2 for amplifying a transmission signal in the 5 GHz band is connected. 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 RX2, and the receiving side demultiplexing circuit DIP2 and the receiving terminal RX5 are connected to each other. A low noise amplifier circuit LNA2 for amplifying a received signal in the 5 GHz band is connected between them. A band pass filter BPF3 is connected to the output side of the low noise amplifier circuit LNA1, and a low pass filter LPF3 is connected to the output side of the low noise amplifier circuit LNA2. In the front end module shown in FIG. 5, the high-frequency circuit has a low-noise amplifier LNA1 in the 2.4 GHz band reception path on the low-frequency side, and the band-pass filter BPF4 according to the present invention on the input side of the low-noise amplifier. Is connected.

  FIG. 6 is a lamination pattern diagram of a laminated body of front end modules having the equivalent circuit shown in FIG. The bandpass filter according to the present invention may be used for the bandpass filter BPF1 and the bandpass filter unit BPF4 constituting a part of the receiving-side branching circuit DIP2. 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. FIG. 7 shows the arrangement of each bandpass filter viewed from the stacking direction. The bandpass filter BPF1 arranged in the 2.4 GHz band transmission path is arranged in the lower right of the center of the laminate in the figure. The LC electrode patterns of the bandpass filter BPF1 and the bandpass filter BPF4 are formed from the fourth layer to the twelfth layer sandwiched between the third layer and the thirteenth layer where the ground electrode is formed. Yes. That is, the lines ltbb1a, ltbb1b, ltbb2a, ltbb2b constituting the first coil pattern part are in the eighth layer and the ninth layer, and the lines ltbb1c-e, ltbb2c-e constituting the second coil pattern part are the tenth layer. To 12th layer. Capacitance electrodes (ctbb1a, ctbb1b, ctbb2, ctbb3a, ctbb3b, ctbb4, ctbb5a, ctbb5b) constituting the coupling capacitance and ground capacitance of the bandpass filter BPF1 are formed in the fourth to seventh layers. The configuration of each line and each capacitor electrode constituting the bandpass filter BPF1 is the same as that shown in FIG.

  In the embodiment shown in FIG. 6, the same configuration as the bandpass filter shown in FIG. 1 is used for the bandpass filter BPF4. The band-pass filter BPF1 and the band-pass filter unit BPF4 are arranged via a plurality of shield vias and a strip-shaped shield electrode connected thereto, but the directions in which the coupled resonance lines are juxtaposed are different by 90 degrees. The ends of the first coil pattern portions formed in the eighth layer and the ninth layer are connected in parallel to form a parallel line, and the second coil pattern portions formed in the tenth to twelfth layers The points where the ends are connected in parallel to form a parallel line, the first coil pattern portion of the eighth layer and the ninth layer, and the second coil pattern portion of the tenth to twelfth layers are in series. The point etc. which are connected and the helical inductance element is formed are the same as that of the band pass filter BPF1. BPF1 and BPF4 configured using parallel lines are particularly excellent in insertion loss. The lines lrdb1a, lrdb1b, lrdb2a, lrdb2b constituting the first coil pattern part are in the eighth layer and the ninth layer, and the lines lrdb1c to e, lrdb2c to e constituting the second coil pattern part are the tenth layer to the tenth layer. It is formed in 12 layers. Capacitance electrodes (crdb1a, crdb1b, crdb2, crdb3a, crdb3b, crdb4, crdb5a, crdb5b) constituting the coupling capacitance and ground capacitance of the bandpass filter BPF4 are formed in the fourth to seventh layers. The widths of the line lrdb1c and the line lrdb2c formed in the same dielectric layer (the tenth layer) and arranged side by side are larger than the widths of the lines formed in the other dielectric layers. The via holes for connecting the ends of the lines lrdb1c to e and lrdb2c to e constituting the second coil pattern part (the end opposite to the end connected to the first coil pattern) are the lines. It is formed at a position spaced from the end of the. With such a configuration, it is possible to suppress characteristic variation due to stacking deviation.

  On the other hand, in the embodiment shown in FIG. 6, the band-pass filter BPF2 and the band-pass filter BPF3 use a linear resonance line instead of the spiral resonance line. The bandpass filter can provide an excellent attenuation. That is, a band pass filter BPF3 configured using a linear resonance line is connected to the output side of the low noise amplifier LNA1. As shown in FIG. 7, the bandpass filter BPF2 is provided at the upper right corner of the laminate, and the bandpass filter BPF3 is provided at the lower right corner. The bandpass filter BPF2 is a three-stage resonator bandpass filter, and linear resonance lines are juxtaposed on the dielectric layer and coupled to each other. The band-pass filter BPF3 is a two-stage resonator band-pass filter, and each of the polygonal resonance lines is juxtaposed on the dielectric layer and coupled to each other. Each resonant line pattern is composed of a parallel line in which one ends of line patterns lrbb1a to c and lrbb2a to c having the same shape formed in different dielectric layers are connected to each other. In the resonance line of the bandpass filter BPF2, lines formed in the eighth to eleventh layers constitute one resonance line. Similarly, in the resonance line of the bandpass filter BPF3, linear lines ltba1a to d, ltba2a to d, and ltba3a to d formed in the ninth to eleventh layers respectively constitute one resonance line. The seventh layer and the thirteenth layer sandwiching the eighth to twelfth layers in which the first coil pattern portion and the second coil pattern portion of the BPF1 and BPF4 are formed adjacent to each other in the stacking direction are the first layer 13th layer. A capacitor electrode and a ground electrode are formed so as to sandwich the coil pattern portion and the second coil pattern. On the other hand, on the seventh layer and the twelfth layer sandwiching the eighth to eleventh layers where the BPF2 resonance line is formed adjacent to each other in the stacking direction, the capacitor electrode and the ground electrode sandwiching these layers are not formed. Instead, they are formed in the sixth and thirteenth layers through one layer. Similarly, the 8th and 12th layers sandwiching the ninth to eleventh layers in which the resonance lines of BPF3 are formed are adjacent to each other in the laminating direction, and capacitive electrodes and ground electrodes are formed so as to sandwich them. Instead, they are formed in the seventh layer and the thirteenth layer through one layer.

  The band-pass filter according to the present invention can be applied to each band-pass filter in a high-frequency component such as a front-end module. In particular, the band-pass filter disposed on the input side of the low-noise amplifier in the reception path uses the band-pass filter according to the present invention in which a resonance line is formed in a spiral shape, and the band disposed on the output side of the reception low-noise amplifier. As the pass filter, it is more preferable to use a band pass filter in which a resonance line is formed in a linear shape. According to this circuit configuration, the BPF of the present invention can reduce the insertion loss on the input side of the low noise amplifier, and the BPF on the output side of the low noise amplifier can secure the attenuation amount outside the band, thereby greatly improving the reception sensitivity. Things will be possible. This effect is brought about by arranging the band-pass filters having relatively different insertion loss and attenuation amount before and after the low-noise amplifier in the high-frequency module including the low-noise amplifier. The configuration is not limited to the bandpass filter, and other configurations may be used.

  The bandpass filter of the present invention can be widely applied not only to the high frequency switch module and the front end 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 (IEEE802.11b and / or IEEE802.11g) and 5 GHz band wireless LAN (IEEE802.11a). 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 exploded perspective view for showing electrode arrangement of a band pass filter concerning an embodiment of the present invention. It is the schematic diagram which looked at the connection state of the resonant line of a laminated substrate from the laminated substrate side. It is a figure which shows the overlapping state of the lines which form a resonant line. It is an equivalent circuit schematic of the band pass filter concerning the embodiment of the present invention. It is an equivalent circuit diagram of the front end module according to the embodiment of the present invention. It is a sheet | seat development view of the front end module which concerns on embodiment of this invention. It is a figure which shows arrangement | positioning of the band pass filter in the front end module which concerns on embodiment of this invention.

Explanation of symbols

cb1, cb6: input / output capacitors cb2, cb5: grounded capacitors cb3, cb4: coupling capacitors cb1a, cb2a, cb5a, cb6a: capacitor electrodes cb1b, cb2b, cb5b, cb6b: capacitor electrodes lb1, lb2: resonant lines lb1a-lb1 ˜lb2e: Line GND: Ground electrode P1, P2: Input / output port p1, p2: Input / output electrode 1: Via conductor

Claims (8)

A bandpass filter comprising two or more resonant lines arranged in a direction perpendicular to the stacking direction in a stacked substrate formed by stacking a plurality of dielectric layers,
Each of the resonance lines includes at least a first coil pattern portion formed in the dielectric layer and a second coil pattern portion formed in a dielectric layer different from the first coil pattern, The first and second coil pattern portions are formed in a spiral by connecting in series,
A band-pass filter, wherein at least one of the first and second coil pattern portions is formed as a parallel line on a plurality of dielectric layers.   The bandpass filter according to claim 1, wherein at least one of the parallel lines has a width larger than that of the other lines of the parallel line.   The width of at least one of the parallel lines is larger than the other lines of the parallel line so as to spread inside a spirally formed resonant line. The described bandpass filter.   4. The bandpass filter according to claim 2, wherein the line having a width larger than that of the other line is disposed in an intermediate layer among a plurality of dielectric layers in which the resonance line is formed. . The high-frequency circuit used in the communication device is a high-frequency component configured 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 has a band-pass filter;
A high-frequency component using the band-pass filter according to claim 1 as the band-pass filter. The high frequency circuit has a low noise amplifier,
The high-frequency component according to claim 5, wherein the band-pass filter is connected to an input side of the low-noise amplifier.   The high-frequency component according to claim 6, wherein a band-pass filter configured using a linear resonance line is connected to an output side of the low-noise amplifier.   A communication device using the bandpass filter according to any one of claims 1 to 4 or the high-frequency component according to any one of claims 5 to 7.

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