JP4550915B2 - FILTER CIRCUIT, FILTER CIRCUIT ELEMENT, MULTILAYER CIRCUIT BOARD AND CIRCUIT MODULE HAVING THE SAME - Google Patents

Description

  The present invention relates to a band-pass filter circuit and a filter circuit element having a wide pass band, a multilayer circuit board and a circuit module including the same.

  In recent years, development of a wireless system using a broadband has been studied. In a wireless system using a wide band, a band pass filter (BPF) that selects a necessary signal and an unnecessary signal is desired to be matched in a wide band and to have a low insertion loss.

  For example, Japanese Patent Application Laid-Open No. 2005-295316 (Patent Document 1) discloses a conventional filter intended for use in a wide band. A high-frequency ring filter with small loss, flat passband, constant group delay characteristics, and steep attenuation, and a wideband bandpass filter using the same are disclosed.

  Japanese Patent Laying-Open No. 2005-318428 (Patent Document 2) discloses a filter device and a circuit module that are small in size and have a wide band-pass characteristic, and that are configured by a distributed constant circuit and have a band-eliminating characteristic. A filter device having bandpass characteristics by first filter means and second filter means for attenuating frequencies below the low-frequency attenuation pole frequency and above the high-frequency attenuation pole frequency of the band-eliminating characteristics of the first filter; A circuit module having this is disclosed.

Japanese Patent Laying-Open No. 2007-068123 (Patent Document 3) discloses a band-pass filter having a specific band characteristic of 20% or more and low attenuation in the frequency band of the UWB standard. The bandpass filter includes a plurality of coupling conductors that are broad-side coupled, an input-side waveguide that includes an earth conductor and a waveguide conductor, and an electric signal is input to one of the coupling conductors, and a ground conductor and a waveguide conductor. An output side waveguide that outputs an electrical signal from the other one of the coupling conductors is used.
JP 2005-295316 A JP 2005-318428 A JP 2007-068123 A

  However, the filters disclosed in Patent Document 1 and Patent Document 2 are broadband filters using ring resonators, and these filters can be realized with a flat and easy structure, but constitute one resonance circuit. However, since a transmission line having one wavelength or more is required, the problem is that the shape becomes large.

  As a method of realizing with a small resonator, there is a method using the broad sideband coupled resonator described in Patent Document 3. However, this technique requires extremely strong coupling between the resonators in order to realize a wide band, and a process with high accuracy is a prerequisite for this. In addition, since one resonance circuit is realized by two lines, the circuit scale is larger than that of a stub type resonator.

  Each method is a method using a distributed constant circuit, and an example of realizing a wideband filter in a frequency band of 3 to 10 GHz without using a distributed constant element is not known.

  The present invention has been made in view of the above-described problems, and provides a bandpass filter circuit and a filter circuit element that are small and can realize a wideband pass characteristic, and a multilayer circuit board and a circuit module including the same. With the goal.

In order to achieve the above object, the present invention provides a first impedance element provided on an input side, an input terminal connected to an output terminal of the first impedance element, and provided on an output side. A second impedance element made of the same element; a distributed constant resonance circuit having one end connected to a connection point between an output end of the first impedance element and an input end of the second impedance element; and an input of the first impedance element And a third impedance element having one end connected to the end and the other end connected to the output end of the second impedance element, and at least one of the first to third impedance elements has a predetermined concentration. It is constituted by an element having a constant, other impedance element is constituted by an element having a predetermined distributed constant It said first and second impedance elements proposes a filter circuit comprising a transmission line.

  The filter circuit of the present invention is a method of configuring a resonator or a filter using only a distributed constant circuit in the conventional example, whereas a distributed constant resonant circuit, an element having a lumped constant, an element having a distributed constant, By combining these, a filter circuit having a small size and good wideband characteristics, which was difficult in the conventional example, is realized.

  The present invention also provides a filter circuit element in which the filter circuit is formed inside an element body constituting the element body, a multilayer circuit board on which the filter circuit is formed, and the filter circuit. Proposed circuit module.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to provide the filter circuit corresponding to an ultra wide band, the wide band filter circuit which has a some attenuation pole can be provided. Furthermore, an attenuation pole can be provided at the frequency of the harmonic resonance generated by the distributed constant resonance circuit. As a result, a small broadband filter circuit having various characteristics can be realized. In addition, by a new method combining a lumped constant element and a distributed constant element, it is possible to realize an unprecedented small-sized broadband filter circuit in a laminated circuit component and a circuit board.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a filter circuit in a first embodiment of the present invention. The filter circuit of the present invention has a first impedance element 111 having one end connected to the input terminal 101 and an output terminal connected to the output terminal of the first impedance element 111, as in the filter circuit 100 shown in FIG. One end is connected to the connection point between the output terminal of the first impedance element 111 and the input terminal of the second impedance element 112. The other end is connected to the output terminal. And the third impedance element 114 having one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112. . In the first embodiment, the first impedance element 111 and the second impedance element 112 are composed of a distributed constant resonance circuit constituted by a transmission line having a predetermined distributed constant, and the other end of the distributed constant resonance circuit 113 is opened. The third impedance element 114 includes a capacitor having a predetermined lumped constant. The open stub type resonance circuit includes a transmission line having a predetermined distributed constant.

  This filter circuit 100 is a band-pass filter circuit that realizes a wide band by canceling the periodic attenuation pole of the distributed constant stub type resonance circuit which is the distributed constant resonance circuit 113 in principle, and is one distributed constant type. The stub type resonance circuit, two transmission lines (a very short transmission line of about one-tenth wavelength) and one capacitor are very simple.

  In the present embodiment, a filter circuit that realizes a band-pass filter that uses a frequency band of 3 to 10 GHz as a wide-band pass frequency band will be described. Therefore, in this embodiment, the open stub type resonance circuit of the distributed constant resonance circuit 113 is set to have an electrical length of 180 ° and a characteristic impedance of 40Ω when the resonance frequency is 6 GHz.

  FIG. 3 shows a filter circuit as a reference example for comparison with the present invention. The filter circuit 10 is obtained by removing the third impedance element 114 from the filter circuit 100. In general, a distributed constant filter such as a multilayer filter such as the filter circuit 10 shown in FIG. 3 is mainly composed of a stub type resonance circuit having a quarter wavelength or a half wavelength. ing. However, since the impedance of the distributed constant type stub type resonance circuit (distributed constant resonance circuit 113) changes periodically with a tangent function (tan function) depending on the frequency, the attenuation pole (impedance = 0) at an integral multiple of the frequency. ), Passbands (impedance = infinity) are generated alternately. Due to this periodicity, it has been impossible in principle to construct a filter circuit that realizes ultra-wideband characteristics using a distributed constant stub type resonant circuit. That is, as shown in the frequency characteristic diagram of FIG. 4, it can be seen that attenuation poles are generated at frequencies three to five times 3 GHz. Therefore, it can be seen that the band cannot be fundamentally widened by the attenuation pole that appears regularly. In FIG. 4, the horizontal axis represents frequency, and the vertical axis represents attenuation and reflection. Further, in FIG. 4, a characteristic curve A indicates a transmission characteristic, and a characteristic curve B indicates a reflection characteristic. Note that the distributed constant stub type resonant circuit 113, which is the distributed constant resonant circuit 113 in the filter circuit 10 of FIG. 3, has a characteristic of an electrical length of 180 ° and a characteristic impedance = 40Ω at a frequency of 6 GHz.

  FIG. 2 is a diagram illustrating a characteristic example of the filter circuit 100 according to the first embodiment. In FIG. 2, the horizontal axis represents frequency, and the vertical axis represents attenuation and reflection. Further, in FIG. 2, a characteristic curve A indicates a transmission characteristic, and a characteristic curve B indicates a reflection characteristic. As can be seen from FIG. 2, in the filter circuit 100 of the first embodiment, the 9 GHz attenuation pole that the stub type resonance circuit (distributed constant resonance circuit 113) has periodically disappears. It can also be seen that the matching frequency has increased to three. Therefore, the filter circuit 100 eliminates the attenuation pole that the distributed constant stub type resonance circuit has in principle, and widens the pass band of the distributed constant type stub type resonant circuit by increasing the matching frequency.

  The realization condition of the attenuation pole can be easily obtained by performing theoretical analysis. By setting the constant of each impedance element so as to satisfy this condition, the position of the attenuation pole in the frequency characteristic of the filter circuit 100, etc. Can be adjusted.

For example, an example of obtaining the attenuation pole frequency and the matching frequency in the circuit shown in FIG. 1 by theoretical analysis will be described below. Here, as shown in FIG. 5, the characteristic impedances of the transmission lines forming the first impedance element 111 and the second impedance element 112 are Z ₂ , the electrical length is θ ₂ , and the distributed constant resonance circuit 113. Is a half-wavelength open stub and its characteristic impedance is Z ₁ and its electrical length is θ ₁ , and further, the fourth impedance element 114 is a capacitor and its capacitance is C ₁ . Further, it is assumed that the characteristic impedances of the input end side and the output end side are Z ₀ .

  At this time, since the circuits shown in FIGS. 1 and 5 have a symmetrical circuit configuration, even-odd mode analysis can be performed. FIG. 6 is a diagram showing an even mode equivalent circuit, and FIG. 7 is a diagram showing an odd mode equivalent circuit.

The even-mode equivalent circuit shown in FIG. 6 includes a transmission line TL1 having one end connected to the terminal Port1 and a ½ wavelength open stub OES connected to the other end of the transmission line TL1. Here, the characteristic impedance of the terminal Port1 is Z _0, the characteristic impedance of the transmission line TL1 is Z _{2, 2} electrical length theta, the characteristic impedance of the open stub OES is 2Z _1, an electrical length of theta ₁ is there.

The odd-mode equivalent circuit shown in FIG. 7 includes a transmission line TL2 having one end connected to the terminal Port1 and the other end grounded, and a capacitor CP having one end connected to the terminal Port1 and the other end grounded. Has been. Here, the characteristic impedance of the terminal Port1 is Z _0, the characteristic impedance of the transmission line TL1 is Z _{2, 2} electrical length theta, capacitance of the capacitor CP is 2C _1.

From the even mode equivalent circuit shown in FIG. 6, the input impedance Z _even and the reflection coefficient Γ _even in the even mode are expressed by the following equations (1) and (2), respectively.

The odd-mode input impedance Z _odd and the reflection coefficient Γ _odd are expressed by the following equations (3) and (4), respectively.

Using the above equations (2) and (4), S ₁₁ and S ₂₁ can be derived as shown in the following equations (5) and (6).

Therefore, the matching frequency in the circuits shown in FIGS. 1 and 5 is determined by Γ _even = −Γ _odd which is a condition that satisfies S ₁₁ = 0. The attenuation pole frequency in the circuits shown in FIGS. 1 and 5 is determined by Γ _even = Γ _odd which is a condition satisfying S ₂₁ = 0.

  It goes without saying that the attenuation pole frequency and the matching frequency in the circuit can be obtained by performing even-odd mode logic analysis as described above even in circuits other than the circuit configuration of FIG. 1 described later.

  The frequency characteristic in Example 1 is shown in FIG. In FIG. 8, the horizontal axis represents frequency, and the vertical axis represents attenuation and reflection. In addition, the characteristic curve A indicates the pass characteristic, and the characteristic curve B indicates the reflection characteristic. In the first embodiment, the transmission line constituting each of the first impedance element 111 and the second impedance element 112 has a characteristic impedance of 30Ω, an electrical length at a frequency of 6 GHz is 18 °, and the transmission constituting the distributed constant resonance circuit 113. The characteristic impedance of the line is 40Ω, the electrical length when the frequency is 6 GHz is 180 °, and the capacitance of the capacitor constituting the third impedance element 114 is 0.68 pF.

  The frequency characteristics in Example 2 are shown in FIG. In FIG. 9, the horizontal axis represents frequency, and the vertical axis represents attenuation and reflection. In addition, the characteristic curve A indicates the pass characteristic, and the characteristic curve B indicates the reflection characteristic. In the second embodiment, the transmission line constituting each of the first impedance element 111 and the second impedance element 112 has a characteristic impedance of 32Ω, the electrical length at a frequency of 6 GHz is 56 °, and the transmission constituting the distributed constant resonance circuit 113. The characteristic impedance of the line is 40Ω, the electrical length when the frequency is 6 GHz is 180 °, and the capacitance of the capacitor constituting the third impedance element 114 is 0.14 pF.

  The position of the attenuation pole on the low frequency side, that is, the 3 GHz attenuation pole in the frequency characteristics of FIGS. 8 and 9 depends only on the length of the open stub type resonance circuit constituting the distributed constant resonance circuit 113. Further, the attenuation pole on the high frequency side, that is, the attenuation pole existing on the higher frequency side than 8 GHz in these examples, includes the transmission line and the third impedance element 114 constituting the first impedance element 111 and the second impedance element 112. It can be controlled by the capacitor to be configured. For example, if the electrical length of the transmission line constituting the first impedance element 111 and the second impedance element 112 is increased and the capacitance of the capacitor constituting the third impedance element 114 is set to be small, the attenuation pole on the high frequency side has a low frequency. Move towards. Further, if the electrical length of the transmission line constituting the first impedance element 111 and the second impedance element 112 is reduced and the capacitance of the capacitor constituting the third impedance element 114 is set to be large, the attenuation pole on the high frequency side has a high frequency. Move towards.

  It is also possible to make two or more attenuation poles adjacent to the high frequency side as shown in the frequency characteristics shown in FIGS. Also in this case, the position of the attenuation pole on the low frequency side depends only on the length of the open stub type resonance circuit constituting the distributed constant resonance circuit 113. The number and position of the attenuation poles on the high frequency side are the characteristic impedance and electrical length of the transmission line constituting the first impedance element 111 and the second impedance element 112, and the open stub type resonance circuit constituting the distributed constant resonance circuit 113. It depends on the characteristic impedance and the capacitance of the capacitor constituting the third impedance element 114.

  Next, a second embodiment of the present invention will be described.

  FIG. 12 is a diagram showing a filter circuit according to the second embodiment of the present invention, and FIG. 13 is a diagram showing frequency characteristics thereof. In the present embodiment, a filter circuit that realizes a band-pass filter that uses a frequency band of 3 to 10 GHz as a wide pass frequency band will be described.

  The filter circuit 100B shown in FIG. 12 has a first impedance element 111 having one end connected to the input terminal 101, an input terminal connected to the output terminal of the first impedance element 111, and an output terminal connected to the output terminal. A second impedance element 112 made of the same element as the first impedance element 111; a distributed constant resonance circuit 113 having one end connected to a connection point between the output end of the first impedance element 111 and the input end of the second impedance element 112; The third impedance element 114 has one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112.

  In the second embodiment, the first impedance element 111 and the second impedance element 112 are inductors having a predetermined lumped constant, and the distributed constant resonance circuit 113 is a transmission line having a predetermined distributed constant with the other end opened. The third impedance element 114 is constituted by a capacitor having a predetermined lumped constant.

  Similarly to the filter circuit 100 of the first embodiment, the filter circuit 100B of the second embodiment cancels the periodic attenuation pole that the distributed constant stub type resonance circuit 113, which is the distributed constant resonance circuit 113, has in principle, and widens the bandwidth. The realized band-pass filter circuit has a very simple configuration including one distributed constant stub type resonance circuit, two inductors, and one capacitor.

  In the present embodiment, the inductance of the inductors constituting the first and second impedance elements 111 and 112 is 0.35 nH, the characteristic impedance of the transmission line constituting the distributed constant resonance circuit 113 is 18Ω, and the electrical length when the frequency is 6 GHz is 18 ° The capacitance of the capacitor constituting the third impedance element 114 is 0.54 pF.

  Thereby, also in this embodiment, as shown in FIG. 13, the band pass type filter circuit which makes the frequency band of 3-10 GHz into a wide pass frequency band is implement | achieved.

  Note that the condition for realizing the attenuation pole can be easily obtained by performing theoretical analysis in the same manner as in the first embodiment, and by setting the constant of each impedance element so as to satisfy this condition, the filter circuit 100B can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, a third embodiment of the present invention will be described.

  FIG. 14 is a diagram showing a filter circuit according to the third embodiment of the present invention, and FIG. 15 is a diagram showing frequency characteristics thereof. In the present embodiment, a filter circuit that realizes a band-pass filter that uses a frequency band of 3 to 10 GHz as a wide pass frequency band will be described.

  The filter circuit 100C shown in FIG. 14 has a first impedance element 111 having one end connected to the input terminal 101, an input terminal connected to the output terminal of the first impedance element 111, and an output terminal connected to the output terminal. A second impedance element 112 made of the same element as the first impedance element 111; a distributed constant resonance circuit 113 having one end connected to a connection point between the output end of the first impedance element 111 and the input end of the second impedance element 112; The third impedance element 114 has one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112.

  In the third embodiment, the first impedance element 111 and the second impedance element 112 are formed of capacitors having a predetermined lumped constant, and the distributed constant resonance circuit 113 is a transmission line having a predetermined distributed constant with the other end opened. The third impedance element 114 is constituted by a transmission line having a predetermined distributed constant.

  Similarly to the filter circuit 100 of the first embodiment, the filter circuit 100C of the third embodiment cancels the periodic attenuation pole that the distributed constant stub type resonance circuit 113, which is the distributed constant resonance circuit 113, has in principle, and widens the bandwidth. The realized band-pass filter circuit has a very simple configuration including one distributed constant stub type resonance circuit, two capacitors, and one distributed constant transmission line.

  In this embodiment, the capacitance of the capacitors constituting the first and second impedance elements 111 and 112 is 1.14 pF, the electrical impedance when the characteristic impedance of the transmission line constituting the distributed constant resonance circuit 113 is 32.5Ω, and the frequency is 6 GHz. 180 °, the characteristic impedance of the transmission line constituting the third impedance element 114 is 30Ω, and the electrical length when the frequency is 6 GHz is 36 °.

  Thereby, also in the present embodiment, as shown in FIG. 15, a band-pass filter circuit having a frequency band of 3 to 10 GHz and a wide pass frequency band is realized.

  Note that the condition for realizing the attenuation pole can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constant of each impedance element so as to satisfy this condition, the filter circuit 100C can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, a fourth embodiment of the present invention will be described.

  FIG. 16 is a diagram showing a filter circuit according to a fourth embodiment of the present invention, and FIG. 17 is a diagram showing frequency characteristics thereof. In the present embodiment, a filter circuit that realizes a band-pass filter having a frequency band of 4 to 14 GHz and a wide pass frequency band will be described.

  The filter circuit 100D shown in FIG. 16 has a first impedance element 111 having one end connected to the input terminal 101, an input terminal connected to the output terminal of the first impedance element 111, and an output terminal connected to the output terminal. A second impedance element 112 made of the same element as the first impedance element 111; a distributed constant resonance circuit 113 having one end connected to a connection point between the output end of the first impedance element 111 and the input end of the second impedance element 112; The third impedance element 114 has one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112.

  In the fourth embodiment, the first impedance element 111 and the second impedance element 112 are composed of capacitors having a predetermined lumped constant, and the distributed constant resonance circuit 113 is a transmission line having a predetermined distributed constant with the other end opened. The third impedance element 114 is constituted by an inductor having a predetermined lumped constant.

  Similarly to the filter circuit 100 of the first embodiment, the filter circuit 100D of the fourth embodiment cancels the periodic attenuation pole that the distributed constant stub type resonance circuit 113, which is the distributed constant resonance circuit 113, in principle, and widens the bandwidth. The realized band-pass filter circuit has a very simple configuration including one distributed constant stub type resonance circuit, two inductors, and one capacitor.

  In the present embodiment, the capacitance of the capacitors constituting the first and second impedance elements 111 and 112 is 1.416 pF, the transmission line constituting the distributed constant resonance circuit 113 has the characteristic impedance of 35.2Ω, and the electrical length when the frequency is 6 GHz. Is 180 °, and the inductance of the inductor constituting the third impedance element 114 is 0.42 nH.

  Thereby, also in the present embodiment, as shown in FIG. 17, a band-pass filter circuit having a wide frequency band of 4 to 14 GHz is realized.

  Note that the condition for realizing the attenuation pole can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constant of each impedance element so as to satisfy this condition, the filter circuit 100D can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, another embodiment of the present invention will be described.

  Here, an example in which the configuration of the distributed constant resonance circuit 113 is changed will be described.

  Examples of modified configuration examples of the distributed constant resonance circuit 113 include configurations shown in FIGS. The configuration example shown in FIG. 18 is a short stub type resonance circuit including a transmission line 121 having a predetermined distributed constant whose other end is grounded. The configuration example shown in FIG. 19 includes a transmission line 122 having a predetermined distributed constant whose other end is grounded via a capacitor 123. The configuration example shown in FIG. 20 includes a transmission line 125 having a predetermined distributed constant with a capacitor 124 connected to one end and the other end grounded. The configuration example shown in FIG. 21 is obtained by connecting one ends of two transmission lines 126 and 127 having a predetermined distributed constant with the other ends open. The configuration example shown in FIG. 22 is obtained by connecting one ends of two transmission lines (distributed constant resonance circuits) 128 and 129 having a predetermined distributed constant whose other end is grounded.

  Next, as a fifth embodiment of the present invention, an example in which the transmission line shown in FIG. 18 is used as the distributed constant resonance circuit 113 will be described.

  FIG. 23 is a diagram illustrating a filter circuit according to a fifth embodiment of the present invention, and FIG. 24 is a diagram illustrating frequency characteristics thereof. In the present embodiment, a filter circuit that realizes a band-pass filter that uses a frequency band of 3 to 10 GHz as a wide pass frequency band will be described.

  A filter circuit 100E shown in FIG. 23 has a first impedance element 111 having one end connected to the input terminal 101, an input terminal connected to the output terminal of the first impedance element 111, and an output terminal connected to the output terminal. A second impedance element 112 made of the same element as the first impedance element 111; a distributed constant resonance circuit 121 having one end connected to a connection point between the output end of the first impedance element 111 and the input end of the second impedance element 112; The third impedance element 114 has one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112.

  In the fifth embodiment, the first impedance element 111 and the second impedance element 112 are composed of a distributed constant resonance circuit configured by a transmission line having a predetermined distributed constant, and the other end of the distributed constant resonance circuit 121 is grounded. The third impedance element 114 is formed of a capacitor having a predetermined lumped constant. The third impedance element 114 includes a short stub type resonance circuit including a transmission line having a predetermined distributed constant.

  The filter circuit 100E of the fifth embodiment is a band-pass filter circuit realizing a wide band, and has a very simple configuration including one distributed constant stub type resonance circuit, two transmission lines, and one capacitor. .

  In the present embodiment, the transmission line (distributed constant resonance circuit) constituting the first and second impedance elements 111 and 112 has a characteristic impedance of 50Ω, the electrical length at a frequency of 6 GHz is 180 °, and the transmission constituting the distributed constant resonance circuit 121. The characteristic impedance of the line is 50Ω, the electrical length when the frequency is 6 GHz is 20 °, and the capacitance of the capacitor constituting the third impedance element 114 is 0.85 pF.

  Thereby, also in the present embodiment, as shown in FIG. 24, a band-pass filter circuit having a wide frequency band of 3 to 10 GHz is realized.

  The attenuation pole realization condition can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constants of the impedance elements so as to satisfy this condition, the filter circuit 100E can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, an example in which the transmission line 122 and the capacitor 123 shown in FIG. 19 are used as the distributed constant resonance circuit 113 will be described as a sixth embodiment of the present invention.

  FIG. 25 is a diagram showing a filter circuit according to the sixth embodiment of the present invention, and FIG. 26 is a diagram showing frequency characteristics thereof. In the present embodiment, a filter circuit that realizes a band-pass filter having a wide frequency band of 7 to 13 GHz as a wide pass frequency band will be described.

  The filter circuit 100F shown in FIG. 25 has a first impedance element 111 having one end connected to the input terminal 101, an input terminal connected to the output terminal of the first impedance element 111, and an output terminal connected to the output terminal. A transmission line 122 having one end connected to a connection point between the output terminal of the first impedance element 111 and the input terminal of the second impedance element 112; One end is connected to the other end of 122 and the other end is grounded, and one end is connected to the input end of the first impedance element 111 and the other end is connected to the output end of the second impedance element 112. And a third impedance element 114.

  In the sixth embodiment, the first impedance element 111 and the second impedance element 112 are composed of distributed constant resonance circuits constituted by transmission lines having a predetermined distributed constant, and the third impedance element 114 has a predetermined lumped constant. It is comprised by the capacitor which has.

  The filter circuit 100F of the sixth embodiment is a band-pass filter circuit that realizes a wide band, and has a very simple configuration including one distributed constant type stub type resonance circuit resonator, two transmission lines, and two capacitors. It is.

  In this embodiment, the transmission line (distributed constant resonance circuit) constituting the first and second impedance elements 111 and 112 has a characteristic impedance of 35Ω, the electrical length at a frequency of 6 GHz is 18 °, and the transmission line that constitutes the distributed constant resonance circuit. The characteristic impedance of 122 is 50Ω, the electrical length when the frequency is 6 GHz is 180 °, the capacitance of the capacitor 123 is 2 pF, and the capacitance of the capacitor constituting the third impedance element 114 is 1.15 pF.

  Thereby, also in the present embodiment, as shown in FIG. 26, a band-pass filter circuit is realized in which the frequency band of 7 to 13 GHz is a wide pass frequency band.

  Note that the condition for realizing the attenuation pole can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constant of each impedance element so as to satisfy this condition, the filter circuit 100F can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, as a seventh embodiment of the present invention, an example in which the capacitor 124 and the transmission line 125 shown in FIG. 20 are used as the distributed constant resonance circuit 113 will be described.

  FIG. 27 is a diagram showing a filter circuit in a seventh embodiment of the present invention, and FIG. 28 is a diagram showing its frequency characteristics. In the present embodiment, a filter circuit that realizes a band-pass filter that uses a 7 to 12 GHz frequency band as a wide pass frequency band will be described.

  A filter circuit 100G shown in FIG. 27 has a first impedance element 111 having one end connected to the input terminal 101, an input end connected to the output end of the first impedance element 111, and an output end connected to the output terminal. A second impedance element 112 made of the same element as the first impedance element 111; a capacitor 124 having one end connected to a connection point between the output terminal of the first impedance element 111 and the input terminal of the second impedance element 112; A transmission line 125 having one end connected to the other end and the other end grounded, and one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112 And a third impedance element 114.

  In the seventh embodiment, the first impedance element 111 and the second impedance element 112 comprise a distributed constant resonance circuit constituted by a transmission line having a predetermined distributed constant, and the third impedance element 114 has a predetermined lumped constant. It is comprised by the capacitor which has.

  The filter circuit 100G of the seventh embodiment is a band-pass filter circuit that realizes a wide band, and has a very simple configuration including one distributed constant stub type resonance circuit, two transmission lines, and two capacitors. .

  In this embodiment, the characteristic impedance of the transmission line constituting the first and second impedance elements 111 and 112 is 37Ω, the electrical length at a frequency of 6 GHz is 30 °, and the characteristic impedance of the transmission line 125 constituting the distributed constant resonance circuit is 40Ω. The electrical length at a frequency of 6 GHz is 180 °, the capacitance of the capacitor 124 is 2 pF, and the capacitance of the capacitor constituting the third impedance element 114 is 0.65 pF.

  Thereby, also in the present embodiment, as shown in FIG. 28, a band-pass filter circuit is realized in which the frequency band of 7 to 12 GHz is a wide pass frequency band.

  The attenuation pole realization condition can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constant of each impedance element so as to satisfy this condition, the filter circuit 100G can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, as an eighth embodiment of the present invention, an example in which the transmission lines 126 and 127 shown in FIG. 21 described above are used as the distributed constant resonance circuit 113 will be described.

  FIG. 29 is a diagram illustrating a filter circuit according to an eighth embodiment of the present invention, and FIG. 30 is a diagram illustrating frequency characteristics thereof. In this embodiment, a filter circuit that realizes a band-pass filter having a frequency band of 4 to 18 GHz and a wide pass frequency band will be described.

  The filter circuit 100H shown in FIG. 29 has a first impedance element 111 having one end connected to the input terminal 101, an input end connected to the output end of the first impedance element 111, and an output end connected to the output terminal. One end is connected to the connection point between the second impedance element 112 made of the same element as the first impedance element 111, and the output terminal of the first impedance element 111 and the input terminal of the second impedance element 112, and the other end is opened. Two transmission lines 126 and 127 and a third impedance element 114 having one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112 are configured.

  In the eighth embodiment, the first impedance element 111 and the second impedance element 112 are composed of a distributed constant resonance circuit constituted by a transmission line having a predetermined distributed constant, and the third impedance element 114 has a predetermined lumped constant. It is comprised by the capacitor which has.

  The filter circuit 100H of the eighth embodiment is a band-pass filter circuit that realizes a wide band, and has a very simple configuration including two distributed constant stub type resonance circuits, two transmission lines, and one capacitor. .

  In the present embodiment, the characteristic impedance of the transmission line constituting the first and second impedance elements 111 and 112 is 45Ω, the electrical length L1 at a frequency of 2 GHz is 18 °, and the characteristic impedance of the transmission line 126 constituting the distributed constant resonance circuit is The third impedance element 114 is configured with an electrical length L2 of 45 ° at 50Ω and a frequency of 2 GHz, a characteristic impedance of the transmission line 127 of 50Ω and an electrical length L3 of 135 ° (= 180 ° −L2) at a frequency of 2 GHz. The capacitance of the capacitor is 1 pF.

  Thereby, also in the present embodiment, as shown in FIG. 30, a band-pass filter circuit having a wide frequency band of 4 to 18 GHz is realized.

  Note that the condition for realizing the attenuation pole can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constants of the impedance elements so as to satisfy this condition, the filter circuit 100H can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  Next, as a ninth embodiment of the present invention, an example in which the transmission lines 128 and 129 shown in FIG. 22 are used as the distributed constant resonance circuit 113 will be described.

  FIG. 31 is a diagram showing a filter circuit according to the ninth embodiment of the present invention, and FIG. 32 is a diagram showing frequency characteristics thereof. In the present embodiment, a filter circuit that realizes a band-pass filter having a frequency band of 1 to 13 GHz and a wide pass frequency band will be described.

  A filter circuit 100I shown in FIG. 31 has a first impedance element 111 having one end connected to the input terminal 101, an input terminal connected to the output terminal of the first impedance element 111, and an output terminal connected to the output terminal. One end of the second impedance element 112 made of the same element as the first impedance element 111 and a connection point between the output terminal of the first impedance element 111 and the input terminal of the second impedance element 112 are connected and the other end is grounded. Two transmission lines 128 and 129 and a third impedance element 114 having one end connected to the input end of the first impedance element 111 and the other end connected to the output end of the second impedance element 112 are configured.

  In the ninth embodiment, the first impedance element 111 and the second impedance element 112 are composed of distributed constant resonance circuits constituted by transmission lines having a predetermined distributed constant, and the third impedance element 114 has a predetermined lumped constant. It is comprised by the capacitor which has.

  The filter circuit 100I of the ninth embodiment is a band-pass filter circuit that realizes a wide band, and has a very simple configuration including two distributed constant stub type resonance circuits, two transmission lines, and one capacitor. .

  In this embodiment, the characteristic impedance of the transmission line constituting the first and second impedance elements 111 and 112 is 45Ω, the electrical length L1 is 18 °, the resonance frequency is 6 GHz, and the characteristic impedance of the transmission line 128 constituting the distributed constant resonance circuit. 30Ω, electrical length L2 at a frequency of 6 GHz is 45 °, transmission line 129 has a characteristic impedance of 60Ω, electrical length L3 at a frequency of 6 GHz is 135 ° (= 180 ° −L2), and the third impedance element 114 is configured. The capacitance of the capacitor is 0.6 pF.

  Thereby, also in the present embodiment, as shown in FIG. 32, a band-pass filter circuit having a frequency band of 1 to 13 GHz and a wide pass frequency band is realized.

  Note that the condition for realizing the attenuation pole can be easily obtained by performing a theoretical analysis in the same manner as in the first embodiment, and by setting the constant of each impedance element so as to satisfy this condition, the filter circuit 100I can be realized. The position of the attenuation pole in the frequency characteristics can be adjusted.

  As described above, the filter circuit of each of the above embodiments is a very useful filter that can realize “ultra-wideband characteristics”, “multi-damping pole characteristics”, and “harmonic resonance suppression characteristics” by setting element values. Circuit.

  It is also possible to configure a BPF (band pass filter) in which two or more sets of any of the filter circuits 100 to 100I are connected in series. For example, in the tenth embodiment of FIG. 33, two sets of filter circuits 100F are connected in series via capacitors 311 to 313 between an input terminal 301 and an output terminal 302 to constitute a BPF 300.

  The frequency characteristics of the BPF 300 are as shown in FIG. In FIG. 34, curve A is an attenuation characteristic curve, and curve B is a reflection characteristic curve. The vertical axis represents attenuation and reflection [dB], and the horizontal axis represents frequency [GHz]. Thus, as shown by the attenuation characteristic curve A, the attenuation is maximal at 4.8 GHz and 17.5 GHz, and as shown by the reflection characteristic curve B, the reflection is 6.7 GHz, 8.6 GHz, Minimum values are shown at 12.0 GHz and 14.3 GHz. The filter circuit 300 is designed so that the pass band is 6 to 10 GHz.

  In the eleventh embodiment shown in FIG. 35, three sets of filter circuits 100F are connected in series via capacitors 411 to 414 between an input terminal 401 and an output terminal 402 to constitute a BPF 400.

  The frequency characteristics of the BPF 400 are as shown in FIG. In FIG. 36, curve A is an attenuation characteristic curve, and curve B is a reflection characteristic curve. The vertical axis represents attenuation and reflection [dB], and the horizontal axis represents frequency [GHz]. Thus, as the attenuation characteristic curve A shows, the attenuation amounts show maximum values at 4.5 GHz, 5.0 GHz, 16.5 GHz, and 20.0 GHz, and the reflection quantity characteristic curve B shows that the reflection amount is The minimum values are shown at 6.3 GHz, 7.0 GHz, 9.0 GHz, 11.8 GHz, 13.8 GHz, and 14.8 GHz. The filter circuit 400 is designed so that the pass band is 6 to 15 GHz.

  Thus, BPF which has the outstanding frequency characteristic can be comprised by connecting any one of the filter circuits 100-100I of this embodiment in series via a capacitor.

  Further, by changing the combination and connection, it is possible to realize a filter circuit, a diplexer circuit, and the like that realize desired characteristics and shapes.

  An example of the external shape of the filter element 530 when the filter circuit 100 is formed as an element is that of the twelfth embodiment shown in FIG. That is, the filter element 530 is formed by laminating the above filter circuit 100 inside a rectangular parallelepiped multilayer body 531 mainly composed of dielectric ceramics, and external terminal electrodes 532 to 535 are formed on the outer surface of the multilayer body 531. It becomes. Here, the external terminal electrode 532 corresponds to the input terminal 101, and the external terminal electrode 533 corresponds to the output terminal 102. The external terminal electrodes 534 and 535 are ground terminals.

  The shape and arrangement of the conductor pattern when another example BPF to which the filter circuit 100F is applied is formed inside the multilayer circuit board is as shown in FIGS. FIG. 38 shows a layout view of only the conductor pattern of the filter circuit element of the modified circuit in which the filter circuit is added to the former stage and the latter stage of the twelfth embodiment as viewed from above. FIG. 39 is a perspective view of the inside showing the arrangement relationship between the electrodes and the arrangement relationship of the via conductors 544 when the inside is seen through from the right side surface AA of FIG. 38 including the ceramic multilayer substrate. It does not show a cross section. FIG. 40 is an exploded perspective view for explaining the arrangement relationship by disassembling only the conductor pattern of FIG.

  38 to 40, reference numeral 540 denotes a multilayer circuit board mainly composed of a dielectric ceramic 540a, in which a plurality of conductor patterns are laminated and arranged, and a filter circuit 590 shown in FIG. 41 (modified example of FIG. 25) described later. Is formed. That is, in the portion of the multilayer circuit board 540 where the filter circuit 590 is formed, ground conductor patterns 541 and 542 parallel to each other are arranged on the front surface and the back surface, respectively, and a predetermined size parallel to the ground conductor patterns 541 and 542 is interposed therebetween. A ground conductor pattern 543 is provided, and the ground conductor pattern 543 is conductively connected to the ground conductor patterns 541 and 542 by a plurality of via conductors 544. Further, an input side conductor pattern 550, an output side conductor pattern 560, a resonance conductor pattern 570, and a connection conductor pattern 580 are provided between the ground conductor patterns 541 and 542.

  The input side conductor pattern 550 is provided so as to be parallel to the ground conductor patterns 541 and 542. One end of the input side conductor pattern 550 is connected to the input side strip line 551, the capacitor electrode 552 of the second capacitor unit connected thereto, and the capacitor electrode 552. The second main resonance part is composed of the strip line 553 and the capacitor electrode 554 connected to the other end of the strip line 553. Here, only the capacitor electrode 554 is disposed so as to face the ground conductor pattern 543.

  The output-side conductor pattern 560 is provided so as to be parallel to the ground conductor patterns 541 and 542 and in the same plane as the input-side conductor pattern 550, and is connected to the output-side strip line 561 and the capacitor electrode 562 of the third capacitor unit connected thereto. And a third main resonance part including a strip line 563 having one end connected to the capacitor electrode 562 and disposed parallel to the strip line 553 and a capacitor electrode 564 connected to the other end of the strip line 563. I have. Here, only the capacitor electrode 564 is disposed so as to face the ground conductor pattern 543.

  The resonance conductor pattern 570 is provided between the input side conductor pattern 550 and the output side conductor pattern 560 in the same plane as these, and is disposed in parallel to the strip line 553 and the strip line 571. And a capacitor electrode 572 connected to the other end of the first main resonance portion. Here, only the capacitor electrode 572 is arranged to face the ground conductor pattern 543.

  The connecting conductor pattern 580 is arranged with a dielectric ceramic 540a interposed in a layer different from the layer in which the input side conductor pattern 550, the output side conductor pattern 560, and the resonance conductor pattern 570 are arranged, and the capacitor electrode 552. A capacitor electrode 581 of the second capacitor unit disposed so as to face the capacitor electrode, a capacitor electrode 585 of the third capacitor unit disposed so as to face the capacitor electrode 562, a strip line 582 having one end connected to the capacitor electrode 581, A connection electrode 583 connected to the other end of the strip line 582, a strip line 584 having one end connected to the connection electrode 583 and the other end connected to the capacitor electrode 585, and a capacitor of the first capacitor unit connected to the capacitor electrode 581 A conductive pattern in which the electrode 586 is formed integrally with the open end of the capacitor electrode 586 via a dielectric ceramic 540a. And the other end open end is arranged so as to face is composed of a first capacitor portion of the capacitor electrode 587 Metropolitan connected to the capacitor electrode 585 through a via conductor 588. The connection electrode 583 is connected to one end of the strip line 571 via the via conductor 573.

  An equivalent circuit of the filter circuit formed in the multilayer circuit board 540 is shown in FIG. In the above configuration, each component of the circuit shown in FIG. 41 is configured as follows.

  That is, the transmission line 593 connected to the input terminal 591 is constituted by the strip line 553, the capacitor 597 is constituted by the capacitor electrode 552 and the capacitor electrode 581, and the transmission line 111 is constituted by the strip line 582.

  Further, the transmission line 594 connected to the output terminal 592 is constituted by a strip line 563, the capacitor 598 is constituted by a capacitor electrode 562 and a capacitor electrode 585, and the transmission line 112 is constituted by a strip line 584.

  The main resonance part of the transmission line 122 and the capacitor 123 is constituted by a strip line 571, a capacitor electrode 572 and a ground conductor pattern 543.

  Further, the capacitor 114 connected between the input end of the input side transmission line 111 and the output end of the output side transmission line 112 is constituted by a capacitor electrode 586 and a capacitor electrode 587 disposed to face the capacitor electrode 586.

  Further, the series resonance circuit of the transmission line 593 connected to the input terminal 591 and the capacitor 595 is constituted by the strip line 553, the capacitor electrode 554 and the ground conductor pattern 543, and the transmission line 594 connected to the output terminal 592 and the capacitor 596 are connected. The series resonant circuit includes a strip line 563, a capacitor electrode 564, and a ground conductor pattern 543.

  The frequency characteristics of the filter circuit (bandpass filter) 590 in the multilayer circuit board 540 configured as described above are as shown in FIG. In the figure, curve A is an attenuation characteristic curve, and curve B is a reflection characteristic curve. The vertical axis represents attenuation and reflection [dB], and the horizontal axis represents frequency [GHz]. As described above, the attenuation characteristic curve A shows a maximum value at 1.8 GHz, 5.2 GHz, and 11.3 GHz, and the reflection quantity characteristic curve B shows that the reflection quantity is 6.5 GHz. The minimum values are shown at 7.0 GHz, 8.8 GHz, and 10.5 GHz. The filter circuit 590 is designed so that the passband is 6 to 11 GHz based on the filter circuit 100F described above.

  When the filter circuit element 530 shown in FIG. 37 is configured, the strip lines 551 and 553 and the capacitor electrode 554 and the strip lines 561 and 563 of the output side conductor pattern 560 and the capacitor shown in FIGS. The electrode 564 may be removed.

  As described above, in the LTCC (Low Temperature Co-fired Ceramics) substrate, the LTCC device, etc., in which the capacitor is easily built, the filter circuit of the present invention can realize a very small structure. it can.

  Next, a thirteenth embodiment of the present invention is described.

  In the thirteenth embodiment, a high-frequency radio circuit module including a bandpass filter (BPF) using the above filter circuit is configured.

  43 and 44 show a thirteenth embodiment of the present invention, FIG. 43 is a side perspective view showing a high-frequency radio circuit module according to the thirteenth embodiment of the present invention, and FIG. 44 shows a thirteenth embodiment of the present invention. It is a block diagram which shows the electric system circuit of a high frequency radio | wireless circuit module.

  In FIG. 43, reference numeral 600 denotes a high-frequency radio circuit module, which configures a radio transmission / reception function unit (radio function unit) on a module substrate 601 composed of a ceramic substrate such as low temperature co-fired ceramics (LTCC) or a wiring circuit substrate such as a resin substrate. Electronic components such as an IC 621 and a passive element 622 are mounted. Further, the upper surface of the module substrate 601 is covered with a shield member 602. In addition, a conductor pattern electrode 611 that forms a band-pass filter (BPF) 631 and a conductor pattern electrode 612 that forms a balun 632 are provided inside the module substrate 601. A circuit constituted by these can be connected to an external circuit via a plurality of external electrodes 641 formed on the bottom surface of the module substrate 601.

  As shown in FIG. 44, the electric system circuit of the high-frequency radio circuit module 600 includes an IC 621, a band-pass filter (BPF) 631, and a balun 632. The input side of the bandpass filter (BPF) 631 is connected to an external antenna 651 through an external electrode 641. The output side of the bandpass filter (BPF) 631 is connected to the input side of the balun 621 inside the module substrate 601, and the output side of the balun 621 constitutes a wireless transmission / reception function unit (wireless function unit) inside the module substrate 601. It is connected to IC621.

  Also in the high-frequency radio circuit module 600 of the present embodiment, the bandpass filter (BPF) 631 to which the filter circuit of the present invention is applied can be formed in a very small structure, as described above. The shape of the high-frequency radio circuit module 600 incorporating the (BPF) 631 can be reduced.

The above-described embodiments are specific examples of the present invention, and the present invention is not limited to the configurations of these embodiments. Various modifications can be made without departing from the spirit of the present invention. For example,
1) As a specific example of the present invention, a filter circuit is described in a multilayer circuit board. However, an impedance element such as a strip line or an open stub resonance circuit which is a distributed constant resonance circuit is provided on one dielectric substrate. Can be combined with discrete components such as capacitors and inductors to form filter circuit elements. When such a filter circuit element is used, it is necessary to design in consideration of the wiring pattern. However, if the circuit configuration is determined, the target filter circuit element can be provided.
2) The present invention can also be applied to a circuit module in which the above-described filter circuit element of 1) and a circuit board combined with discrete components such as IC modules, capacitors, and inductors are integrated.
3) Although only a specific example of the stripline has been described for the distributed constant resonance circuit, it is needless to say that a resonant circuit element with other distributed constants such as a microstripline, a slot line, and a coplanar web guide can be used. Therefore, the target filter circuit element can be provided.

The figure which shows the filter circuit in 1st Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 1st Embodiment of this invention. The figure which shows the filter circuit as a comparative reference example with this invention The figure which shows the frequency characteristic of the filter circuit as a comparative reference example with this invention The figure explaining an example of the theoretical analysis in 1st Embodiment of this invention The figure explaining the even mode equivalent circuit in an example of the theoretical analysis in 1st Embodiment of this invention The figure explaining the odd mode equivalent circuit in an example of the theoretical analysis in 1st Embodiment of this invention The figure which shows the frequency characteristic in Example 1 of 1st Embodiment The figure which shows the frequency characteristic in Example 2 of 1st Embodiment. The figure which shows the frequency characteristic in the other Example of 1st Embodiment. The figure which shows the frequency characteristic in the other Example of 1st Embodiment. The figure which shows the filter circuit in 2nd Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 2nd Embodiment of this invention. The figure which shows the filter circuit in 3rd Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 3rd Embodiment of this invention. The figure which shows the filter circuit in 4th Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 2nd Embodiment of this invention. The figure which shows the modification structural example of the distributed constant resonance circuit in this invention The figure which shows the modification structural example of the distributed constant resonance circuit in this invention The figure which shows the modification structural example of the distributed constant resonance circuit in this invention The figure which shows the modification structural example of the distributed constant resonance circuit in this invention The figure which shows the modification structural example of the distributed constant resonance circuit in this invention The figure which shows the filter circuit in 5th Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 5th Embodiment of this invention. The figure which shows the filter circuit in 6th Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 6th Embodiment of this invention. The figure which shows the filter circuit in 7th Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 7th Embodiment of this invention. The figure which shows the filter circuit in 8th Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 8th Embodiment of this invention. The figure which shows the filter circuit in 9th Embodiment of this invention. The figure which shows the frequency characteristic of the filter circuit in 9th Embodiment of this invention The figure which shows the band pass filter of 10th Embodiment of this invention. The figure which shows the frequency characteristic of the band pass filter of 10th Embodiment of this invention. The figure which shows the band pass filter of 11th Embodiment of this invention. The figure which shows the frequency characteristic of the band pass filter of 11th Embodiment of this invention. External appearance perspective view showing a filter circuit element according to a twelfth embodiment of the present invention. The figure explaining the shape and arrangement | positioning of the conductor pattern of the filter circuit element in 12th Embodiment of this invention The figure explaining the shape and arrangement | positioning of the conductor pattern of the filter circuit element in 12th Embodiment of this invention The figure explaining the shape and arrangement | positioning of the conductor pattern of the filter circuit element in 12th Embodiment of this invention The figure which shows the equivalent circuit of the filter circuit element in 12th Embodiment of this invention The figure which shows the frequency characteristic of the filter circuit element in 12th Embodiment of this invention. Side perspective drawing which shows the high frequency radio | wireless circuit module in 13th Embodiment of this invention. The block diagram which shows the electric system circuit of the high frequency radio | wireless circuit module in 13th Embodiment of this invention.

Explanation of symbols

  100, 100B to 100I ... Filter circuit, 101 ... Input terminal, 102 ... Output terminal, 111 ... First impedance element, 112 ... Second impedance element, 113 ... Distributed constant resonance circuit, 114 ... Third impedance element, 121, 122, 125, 126, 127, 128, 129 ... Transmission line , 123,124 ... Capacitor, 300 ... BPF, 301 ... Input terminal, 302 ... Output terminal, 400 ... BPF, 401 ... Input terminal, 402 ... Output terminal, 530 ... Filter circuit element, 531 ... Multilayer body, 532,533,534,535 ... External terminal electrode 540 ... multilayer circuit board, 540a ... dielectric ceramics, 541,542,543 ... ground conductor pattern, 550 ... input side conductor pattern, 551 ... input side strip line, 552,554 ... capacitor electrode, 553 ... strip line, 560 ... output side conductor pattern, 561 ... Output side strip line, 562,564 ... Capacitor electrode, 563 ... Strip line, 570 ... Resonant conductor pattern, 571 ... Strip line, 572 ... K Pacita electrode, 580 ... Connecting conductor pattern, 581,585,586,587 ... Capacitor electrode, 582 ... Strip line, 583 ... Connection electrode, 584 ... Strip line, 588 ... Via conductor, 590 ... Filter circuit, 591 ... Input terminal, 592 ... Output terminal, 593,594 ... Transmission line, 595,596,597,598 ... Capacitor, 600 ... High-frequency radio circuit module, 601 ... Module board, 602 ... Shield member, 611,612 ... Conductor pattern, 621 ... IC, 622 ... Passive element, 631 ... BPF, 632 ... Balanc, 641 ... External electrode, 651 ... Antenna.

Claims (13)

A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
At least one of the first to third impedance elements is constituted by a lumped constant element , and the other impedance elements are constituted by distributed constant elements ,
The filter circuit, wherein the first and second impedance elements are transmission lines. A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
The filter circuit, wherein the first and second impedance elements are composed of distributed constant elements , and the third impedance element is a capacitor. A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
At least one of the first to third impedance elements is constituted by a lumped constant element , and the other impedance elements are constituted by distributed constant elements ,
The first impedance element and the second impedance element are composed of transmission lines ,
The distributed constant resonance circuit is composed of an open stub type resonance circuit constituted by a transmission line having the other end opened,
The filter circuit, wherein the third impedance element is a capacitor. A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
At least one of the first to third impedance elements is constituted by a lumped constant element , and the other impedance elements are constituted by distributed constant elements ,
The first impedance element and the second impedance element comprise inductors;
The distributed constant resonance circuit is composed of an open stub type resonance circuit constituted by a transmission line having the other end opened,
The filter circuit, wherein the third impedance element is a capacitor. A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
At least one of the first to third impedance elements is constituted by a lumped constant element , and the other impedance elements are constituted by distributed constant elements ,
The first impedance element and the second impedance element are capacitors,
The distributed constant resonance circuit is composed of an open stub type resonance circuit constituted by a transmission line having the other end opened,
The filter circuit, wherein the third impedance element is a transmission line. A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
At least one of the first to third impedance elements is constituted by a lumped constant element , and the other impedance elements are constituted by distributed constant elements ,
The first impedance element and the second impedance element are capacitors,
The distributed constant resonance circuit is composed of an open stub type resonance circuit constituted by a transmission line having the other end opened,
The filter circuit, wherein the third impedance element is an inductor. A first impedance element provided on the input side;
A second impedance element having an input terminal connected to the output terminal of the first impedance element and provided on the output side, and comprising the same element as the first impedance element;
A distributed constant resonance circuit having one end connected to a connection point between the output terminal of the first impedance element and the input terminal of the second impedance element;
A third impedance element having one end connected to the input end of the first impedance element and the other end connected to the output end of the second impedance element;
At least one of the first to third impedance elements is constituted by a lumped constant element , and the other impedance elements are constituted by distributed constant elements ,
The distributed constant resonance circuit includes one or more open stub type resonance circuits configured by a transmission line having the other end opened. The filter circuit according to claim 1, wherein the distributed constant resonance circuit includes one or more short stub type resonance circuits configured by a transmission line having the other end grounded. 2. The distributed constant resonance circuit according to claim 1 , wherein a stub type resonance circuit constituted by a transmission line and a capacitor with the other end grounded are connected in series directly or via another impedance element. 2. The filter circuit according to 2. 2. The distributed constant resonance circuit according to claim 1, wherein a capacitor is connected in series between a stub type resonance circuit constituted by a transmission line and another impedance element whose other end is grounded. 2. The filter circuit according to 2. The filter circuit element according to any one of claims 1 to 10, wherein the filter circuit element is formed inside an element body constituting the element body. 11. A multilayer circuit board, wherein the filter circuit according to claim 1 is formed. A circuit module, wherein the filter circuit according to any one of claims 1 to 10 is formed.

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