JP2021078055A - Impedance converter circuit and impedance converter - Google Patents

Abstract

To provide an impedance converter circuit capable of reducing circuit area, and an impedance converter.SOLUTION: The impedance converter circuit includes a transmission line including lamination of a first wiring layer and a second wiring layer that is connected to the ground. The first wiring layer has a main line and a branch line that is connected to the main line at the branching point. The second wiring layer has a first wiring that is connected to the main line or the branching point, and a second wiring opposing the branch line. For example, when the second wiring is connected to the ground and when a first current flows on the branch line, a second current flows on the second wiring opposite to the first current.SELECTED DRAWING: Figure 5

Description

The present invention relates to an impedance conversion circuit and an impedance converter.

A power distributor that enables connection of four transmission lines having characteristic impedance Z _{0 to} a microstrip line having characteristic impedance Z ₀ while maintaining impedance matching is known (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 9-2461817

However, if an attempt is made to increase the impedance conversion ratio of the characteristic impedance between the input and output, the circuit area may increase.

The present disclosure provides an impedance conversion circuit and an impedance converter capable of reducing the circuit area.

This disclosure is
A transmission line in which a first wiring layer and a second wiring layer connected to the ground are laminated is provided.
The first wiring layer has a main line and a branch line connected to the main line at a branch portion.
The second wiring layer provides an impedance conversion circuit having a first wiring connected to the main line or the branch portion and a second wiring facing the branch line.

In addition, this disclosure is
1st terminal and
2nd terminal and
With the 3rd terminal
A transmission line in which a first wiring layer and a second wiring layer connected to the ground are laminated is provided.
The first wiring layer has a main line connected to the first terminal and a branch line connected to the main line at a branch portion and connected to the second terminal and the third terminal.
The second wiring layer provides an impedance converter having a first wiring connected to the main line or the branch portion and a second wiring facing the branch line.

According to the technique of the present disclosure, it is possible to provide an impedance conversion circuit and an impedance converter capable of reducing the circuit area.

It is a figure which shows the structural example of the impedance converter. It is a top view of the 1st comparative example of an impedance conversion circuit. It is a top view of the 2nd comparative example of the impedance conversion circuit. It is a top view of the 3rd comparative example of the impedance conversion circuit. It is a top view of the 1st configuration example of an impedance conversion circuit. It is sectional drawing of the 1st configuration example of an impedance conversion circuit. It is a circuit diagram of the 1st configuration example of an impedance conversion circuit. It is a figure which illustrates the simulation result of the impedance conversion ratio in the 1st configuration example of an impedance conversion circuit. It is a circuit diagram of a transformer. It is a figure which illustrates the simulation result of the signal in the 1st configuration example of an impedance conversion circuit. It is a top view of the 2nd configuration example of an impedance conversion circuit. It is a circuit diagram of the 2nd configuration example of an impedance conversion circuit. It is a figure which illustrates the simulation result of the impedance conversion ratio in the 2nd configuration example of an impedance conversion circuit. It is a top view of the 3rd configuration example of an impedance conversion circuit. It is sectional drawing of the 3rd structural example of an impedance conversion circuit.

Hereinafter, the technique of the present disclosure will be described with reference to the drawings. In the following description, the X-axis direction, the Y-axis direction, and the Z-axis direction represent a direction parallel to the X-axis, a direction parallel to the Y-axis, and a direction parallel to the Z-axis, respectively. The X-axis direction, the Y-axis direction, and the Z-axis direction are orthogonal to each other. The XY plane, YZ plane, and ZX plane are a virtual plane parallel to the X-axis direction and the Y-axis direction, a virtual plane parallel to the Y-axis direction and the Z-axis direction, and a virtual plane parallel to the Z-axis direction and the X-axis direction, respectively. Represents.

FIG. 1 is a diagram showing a configuration example of an impedance converter. The impedance converter 200 shown in FIG. 1 suppresses attenuation of high-frequency signals passing through the impedance converter 200 by performing impedance matching between different characteristic impedances using a transmission line 30 such as a microstrip line. The impedance converter 200 includes a plurality of connectors 21 and 22,23 and an impedance conversion circuit 100 that connects the plurality of connectors 21, 22, 23 to each other.

The first connector 21 is an example of the first terminal of the impedance converter, and for example, a first external device such as an amplifier 11 is connected to the first connector 21. The first connector 21 is connected to the first port of the impedance conversion circuit 100. The second connector 22 is an example of the second terminal of the impedance converter, and for example, a second external device such as an amplifier 12 is connected to the second connector 22. The second connector 22 is connected to the second port of the impedance conversion circuit 100. The third connector 23 is an example of the third terminal of the impedance converter, and for example, a third external device such as an amplifier 13 is connected to the third connector 23. The third connector 23 is connected to the third port of the impedance conversion circuit 100.

The impedance conversion circuit 100 has a transmission line 30 connected between a plurality of connectors 21, 22, 23. The transmission line 30 has a first port to which the first connector 21 is connected, a second port to which the second connector 22 is connected, and a third port to which the third connector 23 is connected.

The impedance converter 200 is a component that can be used as a distributor that distributes a signal input from the first connector 21 into a signal output from the second connector 22 and a signal output from the third connector 23. When the impedance converter 200 is used as a distributor, for example, the output unit of the amplifier 11 is connected to the first connector 21, the input unit of the amplifier 12 is connected to the second connector 22, and the input unit of the amplifier 12 is connected to the third connector 23. Is connected to the input unit of the amplifier 13.

Alternatively, the impedance converter 200 is a component that can be used as a synthesizer that synthesizes a signal input from the second connector 22 and a signal input from the third connector 23 and outputs the synthesized signal from the first connector 21. Is. When the impedance converter 200 is used as a synthesizer, for example, the input unit of the amplifier 11 is connected to the first connector 21, the output unit of the amplifier 12 is connected to the second connector 22, and the output unit of the amplifier 12 is connected to the third connector 23. Is connected to the output unit of the amplifier 13.

FIG. 2 is a plan view showing an example of an impedance conversion circuit that performs impedance conversion with an impedance conversion ratio of 1: 2. The impedance conversion circuit 100A shown in FIG. 2 includes a transmission line 30 having a branch portion 34. The impedance conversion circuit 100A performs impedance matching between the impedance of 50Ω on the side of the first port 31 and the impedance of 100Ω on the side of the second port 32 and the third port 33.

However, when impedance conversion is desired to be performed with an impedance conversion ratio exceeding 1: 2, the circuit area of the impedance conversion circuit may increase. For example, as shown in FIGS. 3 and 4, we want to perform impedance conversion with an impedance conversion ratio of 1: 4 between the impedance of 50Ω on the 1st port 31 side and the impedance of 200Ω on the 2nd port 32 and the 3rd port 33 side. In some cases. In the impedance conversion circuit 100B of FIG. 3, in order to realize an impedance conversion ratio of 1: 4, the electrical length of the transmission line between the first port 31 and the branch portion 34 is lengthened to λ / 4. The circuit scale increases. In the impedance conversion circuit 100C of FIG. 4, in order to realize an impedance conversion ratio of 1: 4, the electricity of each transmission line between the branch portion 34 and the second port 32 and between the branch portion 34 and the third port 33 Since the length is increased to λ / 4, the circuit scale is increased.

The present disclosure provides a technique capable of reducing the circuit area of an impedance conversion circuit even when impedance conversion is performed with an impedance conversion ratio exceeding 1: 2.

<First configuration example>
FIG. 5 is a plan view of a first configuration example of the impedance conversion circuit according to the technique of the present disclosure. The impedance conversion circuit 101 shown in FIG. 5 can perform impedance matching between the impedance on the first port 41 side and the impedance on the second port 42 and the third port 43 side with an impedance conversion ratio exceeding 1: 2. It has a various configurations. The impedance conversion circuit 101 is a circuit that can be used as a distribution circuit or a synthesis circuit.

The impedance conversion circuit 101 includes a transmission line 91. The transmission line 91 has a first wiring layer 40 connected to ports 41 to 43 and a second wiring layer 50 connected to the ground 62.

FIG. 6 is a cross-sectional view of a first configuration example of the impedance conversion circuit. The first wiring layer 40 and the second wiring layer 50 are conductors formed on the substrate 60 containing a dielectric as a main component, and are laminated with the dielectric portion of the substrate 60 interposed therebetween. The first wiring layer 40 is arranged so as to face the second wiring layer 50 in the thickness direction (Z-axis direction) of the substrate 60.

In FIG. 5, the first wiring layer 40 has a main line 45 to which one end is connected to the first port 41, and branch lines 46 and 47 to which one end is connected to the other end of the main line 45 by a branch portion 44. .. The second port 42 is connected to the other end of the branch line 46, and the third port 43 is connected to the other end of the branch line 47. The second wiring layer 50 has wiring portions 51 and 53 to which one end of each is connected to the main line 45 via a via 61, and wiring portions 52 and 54 facing the branch lines 46 and 47. The wiring portions 52 and 54 are connected to the ground 62. The wiring portions 51 and 53 are examples of the first wiring connected to the main line 45, and the wiring portions 52 and 54 are examples of the second wiring facing the branch lines 46 and 47. The via 61 is formed on the substrate 60 in the Z-axis direction.

Since the wiring portions 52 and 54 face the branch lines 46 and 47, the wiring portions 52 and 54 and the branch lines 46 and 47 can be coupled to each other. Further, since the wiring portions 52 and 54 face the branch lines 46 and 47 in the Z-axis direction, at least a part of the branch lines 46 and 47 overlaps with the wiring portions 52 and 54 in a plan view from the Z-axis direction. Therefore, the circuit area of the impedance conversion circuit 101 in the XY plane can be reduced. Further, since the wiring portions 52 and 54 face the branch portion 44, the degree of coupling between the wiring portions 52 and 54 and the branch lines 46 and 47 is increased, so that the impedance conversion ratio is less likely to deviate due to a dimensional error or the like, and the impedance. The conversion ratio can be easily adjusted.

Further, by replacing the impedance conversion circuit 100 of FIG. 1 with an impedance conversion circuit 101 capable of reducing the circuit area, it is possible to reduce the size of the impedance converter 200 that converts impedance with an impedance conversion ratio exceeding 1: 2. Become.

Next, the configuration of the impedance conversion circuit 101 will be described in more detail.

In FIG. 5, the first wiring layer 40 includes a main line 45 having one end connected to the first port 41, a first branch line 46 having one end connected to the other end of the main line 45 by a branch portion 44, and the main line 45. The other end has a second branch line 47 to which one end is connected by a branch portion 44.

The main line 45 is a wiring portion connected between the first port 41 and the branch portion 44, and extends from the first port 41 to the branch portion 44 in the X-axis direction. The main line 45 may be a conductor portion having a bent shape.

The first branch line 46 is a conductor portion connected to the end portion of the main line 45 by a branch portion 44. The first branch line 46 is a wiring portion connected to the branch portion 44, and is connected between the branch portion 44 and the second port 42. The first branch line 46 is an L-shaped wiring portion that extends from the branch portion 44 in the positive Y-axis direction and then extends to the second port 42 in the positive X-axis direction. The first branch line 46 may be a conductor portion having another shape such as another bent shape or a linear shape.

The second branch line 47 is a conductor portion connected to the end portion of the main line 45 by a branch portion 44. The second branch line 47 is a wiring portion connected to the branch portion 44, and is connected between the branch portion 44 and the third port 43. The second branch line 47 is an L-shaped wiring portion that extends from the branch portion 44 in the negative Y-axis direction and then extends to the third port 43 in the positive X-axis direction. The second branch line 47 may be a conductor portion having another shape such as a bent shape or a linear shape.

The second wiring layer 50 has a connecting portion 55 connected to the intermediate portion of the main line 45 via a via 61, a first wiring portion 51 having one end connected to the connecting portion 55, and one end connected to the connecting portion 55. It has a second wiring unit 53. Further, the second wiring layer 50 includes a grounding portion 56 connected to the ground 62, a third wiring portion 52 connected between the other end of the first wiring portion 51 and the grounding portion 56, and a second wiring portion. It has a fourth wiring portion 54 connected between the other end of the 53 and the grounding portion 56.

The first wiring portion 51 is an L-shaped conductor portion that extends from the connection portion 55 in the positive Y-axis direction and then extends to the end of the third wiring portion 52 in the positive X-axis direction. The second wiring portion 53 is an L-shaped conductor portion that extends from the connection portion 55 in the negative Y-axis direction and then extends in the positive X-axis direction to the end of the fourth wiring portion 54. The first wiring portion 51 and the second wiring portion 53 may be conductor portions having other forms such as other bent shapes and linear shapes.

The third wiring portion 52 is a linear conductor portion extending in the positive Y-axis direction from the grounding portion 56 to the end portion of the first wiring portion 51. The fourth wiring portion 54 is a linear conductor portion extending in the negative Y-axis direction from the grounding portion 56 to the end portion of the second wiring portion 53. The third wiring portion 52 and the fourth wiring portion 54 may be conductor portions having a bent shape.

Since at least a part of the first branch line 46 faces the third wiring portion 52, the degree of coupling between the third wiring portion 52 and the first branch line 46 increases, so that the impedance conversion ratio shifts due to dimensional error or the like. It is unlikely to occur, and the impedance conversion ratio can be easily adjusted. Since at least a part of the second branch line 47 faces the fourth wiring portion 54, the degree of coupling between the fourth wiring portion 54 and the second branch line 47 increases, so that the impedance conversion ratio shifts due to dimensional error or the like. It is unlikely to occur, and the impedance conversion ratio can be easily adjusted. When the grounding portion 56 faces the branching portion 44, the degree of coupling between the wiring portions 52 and 54 extending from the grounding portion 56 and the branching lines 46 and 47 extending from the branching portion 44 increases, so that the impedance conversion ratio due to dimensional error or the like increases. Misalignment is unlikely to occur, and the impedance conversion ratio can be easily adjusted.

FIG. 7 is a circuit diagram of the impedance conversion circuit 101 shown in FIG. _{The input currents I in} from the first port 41 _{are the first currents I 46} and I ₄₇ flowing through the first wiring layer 40 and _{the second currents I 52} and I ₅₄ flowing through the second wiring layer 50 via the via 61. Divide. The current I ₄₆ represents the current flowing through the first branch line 46 via the branch portion 44 of _{the first wiring layer 40, and the current I 47} represents the second branch via the branch portion 44 of the first wiring layer 40. Represents the current flowing through the wire 47. The current I ₅₂ represents the current flowing through the via 61 and the first wiring section 51 to the third wiring section 52, and the current I ₅₄ represents the current flowing through the via 61 and the second wiring section 53 to the fourth wiring section 54. Represents the current flowing through.

As shown in FIG. 7, the impedance conversion circuit 101, when the current I ₄₆ is flowing, is formed so that the current I ₅₂ in the reverse direction flows to the current I _46. This makes it possible to perform impedance conversion between the first port 41 and the second port 42 with an impedance conversion ratio exceeding 1: 2. Further, as shown in FIG. 7, the impedance conversion circuit 101, when the current I ₄₇ is flowing, it is formed to flow the reverse current I ₅₄ and the current I _47. As a result, impedance conversion can be performed between the first port 41 and the third port 43 with an impedance conversion ratio exceeding 1: 2. This is because the coupling circuit between the first branch line 46 and the third wiring portion 52 and the coupling circuit between the second branch line 47 and the fourth wiring portion 54 are formed in the form of a transformer as shown in FIG. Because there is.

FIG. 9 is a circuit diagram of the transformer. If the transmission line TL1 and the transmission line TL2 is attached, voltage _{V in} of the input side, the voltage of the output side is _{V out,}
V _in- 0 = V _out −V _in
Because the relationship is established
V _out = 2V _in
The relationship is obtained. Then, RS of the input-side impedance, the impedance of the output side RL, _{I 1} the current flowing in the current flowing through the impedance RS I, the transmission line TL1, the current flowing through the transmission line TL2 When _{I 2,}
RL = V _out / I ₁
= 2V _{in /} 0.5I
= 4V _in / I
= 4RS
The relational expression is obtained. That is, according to the transformer shown in FIG. 9, theoretically, the impedance ratio between the input side and the output side is 1: 4, so that impedance conversion can be performed with an impedance conversion ratio exceeding 1: 2.

Further, in the transformer shown in FIG. _9, V _out, V _in, the relationship between I 1, _{I 2,} as a matrix formula can be represented by an impedance matrix.

Z ₁₁ and Z ₂₂ represent the single-ended impedance of the transmission line alone, and Z ₁₂ and Z ₂₁ represent the coupling mode impedance between the transmission lines. When the two transmission lines are completely symmetrical, Z ₁₁ = Z ₂₂ and Z ₁₂ = Z ₂₁ are established. The difference between the single-ended impedance and the coupling mode impedance (Z _11- Z ₁₂ ) is called the odd mode impedance Z _o , and twice the odd mode impedance Z _o is called the differential impedance. Further, the sum of the single-ended impedance and coupling mode impedance _(Z 11 ₊ Z ₁₂₎ is referred to as the even mode impedance _{Z e,} 0.5 times of the even mode impedance _{Z e,} that the common mode impedance.

As shown in FIG. 7, in the coupling circuit between the first branch line 46 and the third wiring portion 52, a transmission line (main line 45 and the first wiring portion) having a constant length between the points A and B is used. Since 51) exists, a phase difference may occur between the point A and the point B. Therefore, it is preferable to adjust the length and characteristic impedance of each transmission line so that the phase of the point A and the phase of the point B are aligned in the same manner as in the transformer of FIG. In this respect, the same applies to the coupling circuit between the second branch line 47 and the fourth wiring portion 54.

FIG. 8 is a diagram illustrating a simulation result of an impedance conversion ratio obtained by the impedance conversion circuit 101. As a result of adjusting the length and characteristic impedance of each transmission line, the ratio (impedance conversion ratio) between the _{input impedance Z in} and the output impedance Z _{out is 1: 6.} Therefore, for example, appropriate impedance matching can be performed between the first port 41 having _{an input impedance Z in} of 50 Ω and the second port 42 and the third port 43 having an _{output impedance Z out of 300 Ω.} Further, as shown in FIG. 10, a result of adjusting the length and characteristic impedance of the transmission lines, and the phase of the voltage V _{in (A)} in the phase and the point B of the voltage V _{in (A)} at the point A, substantially uniform ing.

The setting conditions at the time of simulation in FIGS. 8 and 10 show the case where the frequency is 10 GHz. The set values of the length and characteristic impedance of each transmission line are as follows.

Coupling circuit between the first branch line 46 and the third wiring unit 52 (perfect symmetry):
Even mode impedance _Z e = _300Ω
Odd mode impedance Z _o = 30Ω
Electric length = 15 °
Coupling circuit between the second branch line 47 and the fourth wiring unit 54 (perfect symmetry):
Even mode impedance _Z e = _300Ω
Odd mode impedance Z _o = 30Ω
Electric length = 15 °
Main line 45:
Characteristic impedance = 100Ω
Electric length: 10 °
First wiring unit 51 and second wiring unit 53:
Characteristic impedance = 100Ω
Electric length: 30 °

<Second configuration example>
FIG. 11 is a plan view of a second configuration example of the impedance conversion circuit according to the technique of the present disclosure. The impedance conversion circuit 102 shown in FIG. 11 can perform impedance matching between the impedance on the first port 71 side and the impedance on the second port 72 and the third port 73 side with an impedance conversion ratio exceeding 1: 2. It has a various configurations. The impedance conversion circuit 102 is a circuit that can be used as a distribution circuit or a synthesis circuit.

The impedance conversion circuit 102 includes a transmission line 92. The transmission line 92 has a first wiring layer 70 connected to ports 71 to 73 and a second wiring layer 80 connected to the ground 62. The stacking relationship between the first wiring layer 70 and the second wiring layer 80 is the same as that of the first configuration example (see FIG. 6).

In FIG. 11, the first wiring layer 70 has a main line 75 having one end connected to the first port 71 and a branch line 76 having one end directly or indirectly connected to the other end of the main line 75 at a branch portion 74. , 77, 78 and. The second port 72 is connected to the other end of the branch line 76, and the third port 73 is connected to the other end of the branch line 77. The second wiring layer 80 has a wiring portion 81 whose one end is connected to the branch portion 74 via a via 61, and a wiring portion 82 facing the branch line 78. The wiring portion 82 is connected to the ground 62. The wiring portion 81 is an example of the first wiring connected to the branch portion 74, and the wiring portion 82 is an example of the second wiring facing the branch line 78. The via 61 is formed on the substrate 60 in the Z-axis direction.

When the wiring portion 82 faces the branch line 78, the wiring portion 82 and the branch line 78 can be coupled to each other. Further, since the wiring portion 82 faces the branch line 78 in the Z-axis direction, at least a part of the branch line 78 overlaps with the wiring portion 82 in a plan view from the Z-axis direction. The circuit area on the plane can be reduced. Further, since the branch line 78 faces the branch portion 84, the degree of coupling between the wiring portion 82 and the branch line 78 is increased, so that the impedance conversion ratio is less likely to deviate due to a dimensional error or the like, and the impedance conversion ratio can be easily adjusted. become.

Further, by replacing the impedance conversion circuit 100 of FIG. 1 with an impedance conversion circuit 102 capable of reducing the circuit area, it is possible to reduce the size of the impedance converter 200 that converts impedance with an impedance conversion ratio exceeding 1: 2. Become.

Next, the configuration of the impedance conversion circuit 102 will be described in more detail.

In FIG. 11, the first wiring layer 70 includes a main line 75 having one end connected to the first port 71, a first branch line 76 having one end connected to the other end of the main line 75 by a branch portion 74, and the main line 75. The other end has a second branch line 77 to which one end is connected by a branch portion 74. Further, the first wiring layer 70 has a third branch line 78 connected between the first branch line 76 and the second branch line 77.

The main line 75 is a wiring portion connected between the first port 71 and the branch portion 74, and extends from the first port 71 to the branch portion 74 in the X-axis direction. The main line 75 may be a conductor portion having a bent shape.

The first branch line 76 is a conductor portion connected to the end of the main line 75 by a branch portion 74. The first branch line 76 is a wiring portion connected to the branch portion 74, and is connected between the branch portion 74 and the second port 72. The first branch line 76 is an L-shaped wiring portion that extends from the branch portion 74 in the positive Y-axis direction and then extends to the second port 72 in the positive X-axis direction. The first branch line 76 may be a conductor portion having another shape such as a bent shape or a linear shape.

The second branch line 77 is a conductor portion connected to the end of the main line 75 by a branch portion 74. The second branch line 77 is a wiring portion connected to the branch portion 74, and is connected between the branch portion 74 and the third port 73. The second branch line 77 is an L-shaped wiring portion that extends from the branch portion 74 in the negative Y-axis direction and then extends to the third port 73 in the positive X-axis direction. The second branch line 77 may be a conductor portion having another shape such as a bent shape or a linear shape.

The third branch line 78 is a conductor portion connected between the intermediate portion of the first branch line 76 and the intermediate portion of the second branch line 77, and extends in the Y-axis direction. The third branch line 78 may be a conductor portion having a bent shape.

The second wiring layer 80 has a connection portion 83 whose one end is connected to the branch portion 74 via a via 61, a wiring portion 81 whose one end is connected to the connection portion 83, and a branch portion 84 to the other end of the wiring portion 81. It has a wiring portion 82 connected by.

The wiring portion 81 extends in the X-axis direction from the connection portion 83 to the intermediate portion of the wiring portion 82. The wiring portion 81 may be a conductor portion having a bent shape.

The wiring portion 82 is a conductor portion connected to the end portion of the wiring portion 81 by a branch portion 84 located in the middle portion of the wiring portion 82, and extends in the Y-axis direction. The wiring portion 82 is connected between the first grounding portion 85 connected to the ground 62 and the second grounding portion 86 connected to the ground 62. The wiring portion 82 includes a first wiring portion 82A connected between the branch portion 84 and the first grounding portion 85, and a second wiring portion 82B connected between the branch portion 84 and the second grounding portion 86. Has. The first wiring portion 82A faces the first branch line portion 78A of the third branch line 78 in the Z-axis direction, and the second wiring portion 82B faces the second branch line portion 78B of the third branch line 78 in the Z-axis direction. Oppose with. The wiring portion 82 may be a conductor portion having a bent shape.

Since at least a part of the third branch line 78 faces the wiring portion 82, the degree of coupling between the wiring portion 82 and the third branch line 78 is increased, so that the impedance conversion ratio is less likely to shift due to dimensional error or the like, and the impedance. The conversion ratio can be easily adjusted. When the branch portion 84 faces the third branch line 78, the degree of coupling between the first wiring portion 82A and the second wiring portion 82B extending from the branch portion 84 and the third branch line 78 increases, so that due to dimensional error or the like. The impedance conversion ratio is less likely to deviate, and the impedance conversion ratio can be easily adjusted.

FIG. 12 is a circuit diagram of the impedance conversion circuit 102 shown in FIG. _{The input currents I in} from the first port 71 _{are the first currents I 78A} and I _78B flowing through the first wiring layer 70 and _{the second currents I 82A} and I _82B flowing through the second wiring layer 80 via the via 61. Divide. The current I _78A represents a current flowing through the first branch line portion 78A of the first wiring layer 40 via the first branch line 76, and the current I _78B passes through the second branch line 77 of the first wiring layer 40. Then, the current flowing through the second branch line portion 78B is represented. The current I _82A represents the current flowing through the via 61 and the wiring portion 81 to the first wiring portion 82A, and the current I _82B represents the current flowing through the via 61 and the wiring portion 81 to the second wiring portion 82B. Represent.

As shown in FIG. 12, the impedance conversion circuit 102, when the current _{I 78A} is flowing, it is formed to flow the reverse current _{I 82A} and the current _{I 78A.} This makes it possible to perform impedance conversion between the first port 71 and the second port 72 with an impedance conversion ratio exceeding 1: 2. Further, as shown in FIG. 12, the impedance conversion circuit 102, when the current _{I 78B} is flowing, is formed to flow the reverse current _{I 82B} to the current _{I 78B.} As a result, impedance conversion can be performed between the first port 71 and the third port 73 with an impedance conversion ratio exceeding 1: 2. This is because the coupling circuit between the first branch line portion 78A and the first wiring portion 82A and the coupling circuit between the second branch line portion 78B and the second wiring portion 82B are formed in the form of a transformer as shown in FIG. Because it has been done.

FIG. 13 is a diagram illustrating a simulation result of an impedance conversion ratio obtained by the impedance conversion circuit 102. As a result of adjusting the length and characteristic impedance of each transmission line, _{the ratio of the input impedance Z in} and the output impedance Z _out (impedance conversion ratio) is about 1: 4. Therefore, for example, appropriate impedance matching can be performed between the first port 71 having _{an input impedance Z in} of 50 Ω and the second port 72 and the third port 73 having an _{output impedance Z out of 200 Ω.}

The setting condition at the time of simulation in FIG. 13 shows the case where the frequency is 10 GHz. The set values of the length and characteristic impedance of each transmission line are as follows.

Coupling circuit (perfect symmetry) between the first branch line portion 78A and the first wiring portion 82A:
Even mode impedance _Z e = _300Ω
Odd mode impedance Z _o = 30Ω
Electric length = 15 °
Coupling circuit between the second branch line portion 78B and the second wiring portion 82B (perfect symmetry):
Even mode impedance _Z e = _300Ω
Odd mode impedance Z _o = 30Ω
Electric length = 15 °
Wiring part 81:
Characteristic impedance = 100Ω
Electric length: 10 °
First branch line 76 and second branch line 77:
Characteristic impedance = 100Ω
Electric length: 30 °

<Third configuration example>
FIG. 14 is a plan view of a third configuration example of the impedance conversion circuit according to the technique of the present disclosure. The impedance conversion circuit 103 shown in FIG. 14 can perform impedance matching between the impedance on the first port 141 side and the impedance on the second port 142 and the third port 143 side with an impedance conversion ratio exceeding 1: 2. It has a various configurations. The impedance conversion circuit 103 is a circuit that can be used as a distribution circuit or a synthesis circuit.

The impedance conversion circuit 103 includes a transmission line 93. The transmission line 93 has a wiring layer 140 connected to ports 141 to 143 and ground 62. As shown in FIG. 15, the wiring layer 140 is a single-layer conductor formed on the substrate 60 containing a dielectric as a main component. The wiring layer 140 may be arranged so as to face a ground plane (not shown) formed on the substrate 60.

In FIG. 14, the wiring layer 140 has a main line 145 to which one end is connected to the first port 41, and branch lines 146 and 147 to which one end is connected to the other end of the main line 145 by a branch portion 144. Further, the wiring layer 140 has branch lines 148 and 149 in which one ends of the branch lines 155 are connected to the middle portion of the main line 145. The branch line 148 is a conductor connecting the branch portion 155 and the ground 62 so as to face the branch line 146 in the same layer, and the branch line 149 faces the branch line 147 in the same layer. It is a conductor connecting between the branch portion 155 and the ground 62.

Impedance conversion circuit 103, when the current _{I 146} is flowing in the branch line 146, current _{I 148} in the opposite direction is formed to flow in the branch line 148 and the current _{I 146.} This makes it possible to perform impedance conversion between the first port 141 and the second port 142 with an impedance conversion ratio exceeding 1: 2, similar to the above impedance conversion circuit. The impedance conversion circuit 103, when the current _{I 147} is flowing in the branch line 147, current _{I 149} in the opposite direction is formed to flow in the branch line 149 and the current _{I 147.} This makes it possible to perform impedance conversion between the first port 141 and the third port 143 with an impedance conversion ratio of more than 1: 2, similar to the impedance conversion circuit described above.

Although the impedance conversion circuit and the impedance converter have been described above by the embodiment, the present invention is not limited to the above embodiment. Various modifications and improvements, such as combinations and substitutions with some or all of the other embodiments, are possible within the scope of the present invention.

For example, a capacitor may be inserted between the ground portion and the ground 62 in order to suppress the direct current from flowing to the ground 62.

Regarding the above embodiments, the following additional notes will be further disclosed.
(Appendix 1)
A transmission line having a first wiring layer and a second wiring layer connected to the ground is provided.
The first wiring layer has a main line and a branch line connected to the main line at a branch portion.
The second wiring layer is an impedance conversion circuit having a first wiring connected to the main line or the branch portion and a second wiring facing the branch line.
(Appendix 2)
The impedance conversion circuit according to Appendix 1, wherein the second wiring is connected to the ground.
(Appendix 3)
The impedance conversion circuit according to Appendix 1 or 2, wherein when a first current flows through the branch line, a second current flows through the second wiring in the direction opposite to the first current.
(Appendix 4)
The first wiring is connected to the main line and
The impedance conversion circuit according to any one of Appendix 1 to 3, wherein the second wiring faces the branch portion.
(Appendix 5)
The first wiring has a connection portion connected to the main line, a first wiring portion connected to the connection portion, and a second wiring portion connected to the connection portion.
The second wiring is between a grounding portion connected to the ground, a third wiring portion connected between the first wiring portion and the grounding portion, and the second wiring portion and the grounding portion. The impedance conversion circuit according to Appendix 4, which has a fourth wiring portion to be connected.
(Appendix 6)
The impedance conversion circuit according to Appendix 5, wherein the grounding portion faces the branching portion.
(Appendix 7)
The first wiring is connected to the branch portion and is connected to the branch portion.
The branch line is a first branch line connected to the branch portion, a second branch line connected to the connection portion, and a second branch line connected between the first branch line and the second branch line. Has 3 branch lines
The impedance conversion circuit according to any one of Appendix 1 to 3, wherein the second wiring faces the third branch line.
(Appendix 8)
The impedance conversion circuit according to Appendix 7, wherein the second wiring is connected between a first grounding portion connected to the ground and a second grounding portion connected to the ground.
(Appendix 9)
The impedance conversion circuit according to Appendix 8, wherein the first wiring is connected between a connection portion connected to the branch portion and an intermediate portion of the second wiring.
(Appendix 10)
The impedance conversion circuit according to any one of Appendix 1 to 9, wherein the first wiring is connected to the main line or the branch portion via a via.
(Appendix 11)
1st terminal and
2nd terminal and
With the 3rd terminal
A transmission line having a first wiring layer and a second wiring layer connected to the ground is provided.
The first wiring layer has a main line connected to the first terminal and a branch line connected to the main line at a branch portion and connected to the second terminal and the third terminal.
The second wiring layer is an impedance converter having a first wiring connected to the main line or the branch portion and a second wiring facing the branch line.

21,22,23 Connector 30 Transmission line 40,70 First wiring layer 41-43,71-73 Port 44,74 Branch 45,75 Main line 46,47 Branch line 50,80 Second wiring layer 51 First wiring 52 3rd wiring part 53 2nd wiring part 54 4th wiring part 55 Connection part 56 Grounding part 60 Board 61 Via 62 Ground 76 1st branch line 77 2nd branch line 78 3rd branch line 85 1st grounding part 86 2nd Grounding section 91, 92, 93 Transmission line 100, 100A, 100B, 101, 102, 103 Impedance conversion circuit 200 Impedance converter

Claims (10)

A transmission line in which a first wiring layer and a second wiring layer connected to the ground are laminated is provided.
The first wiring layer has a main line and a branch line connected to the main line at a branch portion.
The second wiring layer is an impedance conversion circuit having a first wiring connected to the main line or the branch portion and a second wiring facing the branch line. The impedance conversion circuit according to claim 1, wherein the second wiring is connected to the ground. The impedance conversion circuit according to claim 1 or 2, wherein when a first current flows through the branch line, a second current flows through the second wiring in the direction opposite to the first current. The first wiring is connected to the main line and
The impedance conversion circuit according to any one of claims 1 to 3, wherein the second wiring faces the branch portion. The first wiring has a connection portion connected to the main line, a first wiring portion connected to the connection portion, and a second wiring portion connected to the connection portion.
The second wiring is between a grounding portion connected to the ground, a third wiring portion connected between the first wiring portion and the grounding portion, and the second wiring portion and the grounding portion. The impedance conversion circuit according to claim 4, further comprising a fourth wiring portion to be connected. The impedance conversion circuit according to claim 5, wherein the grounding portion faces the branching portion. The first wiring is connected to the branch portion and is connected to the branch portion.
The branch line is a first branch line connected to the branch portion, a second branch line connected to the branch portion, and a second branch line connected between the first branch line and the second branch line. Has 3 branch lines
The impedance conversion circuit according to any one of claims 1 to 3, wherein the second wiring faces the third branch line. The impedance conversion circuit according to claim 7, wherein the second wiring is connected between a first grounding portion connected to the ground and a second grounding portion connected to the ground. The impedance conversion circuit according to claim 8, wherein the first wiring is connected between a connection portion connected to the branch portion and an intermediate portion of the second wiring. 1st terminal and
2nd terminal and
With the 3rd terminal
A transmission line in which a first wiring layer and a second wiring layer connected to the ground are laminated is provided.
The first wiring layer has a main line connected to the first terminal and a branch line connected to the main line at a branch portion and connected to the second terminal and the third terminal.
The second wiring layer is an impedance converter having a first wiring connected to the main line or the branch portion and a second wiring facing the branch line.

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