JPH11340629A - Printed wiring board with laminated structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce line crosstalks and emission noise by dividing a power supplying conductive layer into multiple portions, and connecting the divided power supplying conductive layer portions by conductors in a printed wiring board. SOLUTION: In a printed wiring board with a laminated structure, a power supplying conductive layer 20 is divided into plural portions, and the divided power supplying conductive layer portions are connected to each other by conductive wires 50 through a conductor 51 mounted on a signaling conductive layer 4. The conductor 51 can include ferrite beads 53 and the like which are of high impedance and loss at high frequencies for removing high frequency component. As a result, resonance frequency by mode can be changed by feeding with signal wires. Consequently, line crosstalks and the like, and electromagnetic interference and emissive noise to the outside can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board for reducing crosstalk between lines and radiation noise in a printed wiring board having a laminated structure.

[0002]

2. Description of the Related Art (1) Description of the Configuration of the Prior Art FIG. The invention of Japanese Patent Application Laid-Open No. H7-111387 relates to a multilayer printed circuit board in which at least a rectangular power supply layer and a rectangular ground layer are laminated. In FIG. 18, reference numeral 100 denotes a power supply layer or a ground layer of the printed wiring board, and 101 denotes an opening which diagonally separates a layer surface of the power supply layer or the ground layer 100 along a diagonal line. In this multilayer printed circuit board, one or both of a power supply layer and a ground layer is provided with an opening 101 for diagonally dividing a layer surface along a diagonal line.

(2) Description of the operation and operation of the prior art Such a multilayer printed circuit board as shown in FIG. 18 has an opening in one or both of a power supply layer and a ground layer, which diagonally partitions the layer surface along a diagonal line. The provision suppresses a resonance phenomenon in a specific frequency band and reduces radiation noise in the frequency band.

[0004]

(1) Description of the Problems of the Prior Art A conventional multilayer printed circuit board is constructed as described above, and has one or both of a power supply layer and a ground layer and a diagonal layer plane. By providing an opening that is obliquely sectioned along, a resonance phenomenon in a specific frequency band is suppressed, and radiation noise in that frequency band is reduced. However, in order to suppress line-to-line crosstalk on the printed circuit board and to prevent high-speed signals flowing through clock signal lines and the like arranged on the printed circuit board from causing electromagnetic interference to the outside of the circuit board, high-speed In a wiring board that adopts a structure in which a signal line is sandwiched between a conductor layer for ground and a conductor layer for power supply, radiation due to the mode fed by the signal line is added, resulting in high radiation noise. And the radiation noise must be further suppressed.

(2) Description of the Object of the Invention The present invention has been made to solve the above-mentioned problems, and is directed to a printed wiring board having a structure in which a signal line is sandwiched between a ground conductor layer and a power supply conductor layer. Provided is a printed wiring board having a laminated structure in which a power supply conductor layer is divided and connected by an inductance element (for example, a lossy inductance element such as a ferrite bead) to reduce line crosstalk and radiation noise. The purpose is to:

[0006]

According to the present invention, there is provided a printed wiring board having a laminated structure in which a signal line is sandwiched between a ground conductor layer and a power supply conductor layer according to the present invention, wherein the power supply conductor layer is divided into a plurality of parts. The divided power supply conductor layers are connected by a conductor.

[0007] The invention is characterized in that the divided power supply conductor layers are connected by an inductance element which is one of the conductors.

Further, the power supply conductor layer is arranged in a region where the signal line is wired.

The signal line is a signal line in which at least electromagnetic coupling between adjacent signal lines occurs in a specific frequency band, and the power supply conductor layer has a region in which the signal line is wired. It is characterized by being arranged in.

Further, the signal lines are not arranged at positions where the signal lines are arranged and overlapped along a gap formed between the divided power supply conductor layers.

[0011] Further, the printed wiring board having the above-mentioned laminated structure,
Further, a signal line is arranged on a layer which is arranged more outwardly of the printed wiring board than the power supply conductor layer, and a signal line sandwiched between the power supply conductor layer and the ground conductor layer is provided on the signal line. That the signal lines routed in a layer disposed on the outer side of the printed wiring board with respect to the conductor layer for power supply are arranged at positions where they do not overlap with a gap formed between the divided power supply conductor layers. Features.

Further, the inductance element is at least a ferrite bead.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, a printed wiring board according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a configuration of a printed wiring board having a laminated structure. FIG. 2 is a diagram illustrating a layer configuration of a printed wiring board having a laminated structure. 1 and 2 show a six-layer substrate as an example. 1 and 2, the signal conductor layer 3 is arranged inside the ground conductor layer 1 and the power conductor layer 2, and is arranged outside (closer to the outside of the substrate than the power conductor layer 2). The signal conductor layer 4 is disposed on the layer and on the layer closer to the outside of the substrate than the ground conductor layer 1). The signal conductor layers 3 and 4 may serve as component mounting surfaces without arranging signals. Alternatively, the component mounting surface may also serve as the signal conductor layer. Each layer is insulated by a dielectric layer 5. In FIG. 2, the dielectric layer 5 is omitted. In the first embodiment, the high-speed signal line is arranged on the signal conductor layer 3 inside the ground conductor layer 1 and the power supply conductor layer 2. Thereby, the outside of the ground conductor layer 1 and the power supply conductor layer 2 (the power supply conductor layer 2
A layer located closer to the outside of the substrate than; and
A layer disposed closer to the outside of the substrate than the ground conductor layer 1) or the outside of the substrate having the six-layer structure shown in FIG. The crosstalk with the wiring in the conductor layer 4 (electromagnetic coupling between signal lines is called crosstalk) and electromagnetic interference to the outside of the substrate are suppressed.

On the other hand, a high-speed signal line is a signal containing a high-frequency component such as a clock signal and a data signal when the printed wiring board is a digital circuit board. For example, a periodic signal contains a harmonic frequency component including a fundamental frequency. This current excites the ground conductor layer 1 and the power conductor layer 2 as parallel flat plates, and generates radiation noise. Particularly near the resonance frequency, radiation noise increases. Therefore, radiation noise is suppressed by dividing by a device having low impedance for direct current and low frequency and high impedance for high frequency and changing the resonance frequency. For example, the power supply conductor layer 2 divided by the conductor penetrating the ferrite beads is divided, and the power supply conductor layer 2 is configured to give a loss to a high-frequency current in the power supply conductor layer 2 to reduce radiation noise. Suppress.

FIGS. 3, 4 and 5 are views for explaining the printed wiring board according to the first embodiment. FIG.
FIG. 1 is a plan view showing a power supply conductor layer 20 of the present invention.
An inductance element, for example, a ferrite bead (a ferrite element is used in the form of powdered, compressed, and sintered ferrite) between the power supply conductor layers 20 divided into four parts (A) to (E). Electric device. By processing in this way, it is possible to increase magnetism, increase specific resistance, and reduce overcurrent loss at high frequencies. "From Nikkei Kogyo Shimbun Excerpt.
The ferrite beads are an example of a ferrite element) and are connected by an inductance element 6 including a conductor penetrating therethrough. The inductance element 6 is not disposed on the power supply conductor layer but on the component mounting surface, for example, the signal conductor layer 4. FIG. 4 is a cross-sectional view taken along line AA of FIG. 3 in which the power supply conductor layer 20 is connected by the inductance element 6. In FIG. 4A, a conductor 51 penetrating a ferrite bead is mounted on the signal conductor layer 4. The conductor 51 penetrating the ferrite beads is connected to the power supply conductor layer 20 by a conductor wire 50 such as a through hole. FIG. 4B shows details of the conductor 51 penetrating the ferrite beads. Conductor 5 penetrating ferrite beads
1 is a ferrite bead 53 (a ferrite block)
Are formed so that the conductor 52 penetrates the inside. In the first embodiment, two layers of signal wiring 30 (hereinafter, signal wiring 30 is also referred to as signal line 30) are laid out between grounding conductor layer 1 and power supply conductor layer 20 shown in FIG. FIG. 5 is a cross-sectional view taken along line BB of FIG. 3 of the signal wiring 30 wired between the grounding conductor layer 1 and the power supply conductor layer 20. The signal wiring 30 in FIG. 5 indicates that it is perpendicular to the paper surface. That is, the signal wiring 30a and the signal wiring 30b are parallel to each other, and are wired at the same angle with respect to the power supply conductor layer 20. However, as long as the signal wiring 30a and the signal wiring 30b are parallel to each other, they may be wired at different angles with respect to the power supply conductor layer 20. Further, in FIG. 3, the power supply conductor layer 20 is divided into four, but may be divided into two or another number. These are the same for the following embodiments.

The above description is applicable to a printed wiring board having a laminated structure in which the signal conductor layer 3 is disposed between the ground conductor layer 1 and the power supply conductor layer 2. Also applies to:

As described above, in the first embodiment, in a printed wiring board having a structure in which a signal line is sandwiched between a ground conductor layer and a power supply conductor layer, the power supply conductor layer is divided and the inductance is reduced. The power supply conductor layers divided by the elements were connected. As a result, the high-frequency component is lost by the through-magnetic conductor using high-frequency, high-impedance, lossy ferrite beads or the like. Further, for a parallel plate formed by the ground conductor layer and the power supply conductor layer, the resonance frequency in the mode fed by the signal line is changed, or an electromagnetic field induced between the ground conductor layer and the power supply conductor layer To reduce radiation noise.

As described above, it is possible to obtain a printed wiring board capable of reducing electromagnetic interference and radiation noise outside of the substrate, such as crosstalk between lines, and a layer of the conductor layer near the outside of the substrate.

Embodiment 2 FIG. 6 is a cross-sectional view for describing a printed wiring board according to the second embodiment. Generally, in a printed wiring board having a laminated structure, the power supply conductor layer has the same size as the wiring board. Here, as shown in FIG. 6, the power supply conductor layer 20 was provided only in a range where the signal wiring 30 between the power supply conductor layer 20 and the ground conductor layer 1 was arranged. Thereby, the area of the power supply conductor layer 20 can be reduced, and the resonance frequency can be shifted to a higher one. FIG. 7A shows that the frequency a is the resonance frequency when the power supply conductor layer 20 and the wiring board have the same size. FIG. 7B shows the signal wiring 3
When the power supply conductor layer 20 is provided only in the range where 0 is arranged, the frequency b (frequency a <frequency b) indicates that it is the resonance frequency. Further, the radiation efficiency in a frequency band lower than the resonance frequency is degraded, and the radiation noise suppressing effect can be enhanced. The signal wiring 30 is disposed at least one pattern width (the width of one pattern is the width of the signal line) inside the power supply conductor layer 20. FIG.
Assuming that the width of the signal line 30c is x, as shown in FIG.
c is arranged inside by y (x ≦ y) from the end of the power supply conductor layer 20. This is to prevent the gap and the signal line from overlapping with each other along the gap formed between the divided power supply conductor layers 20. When the gap and the signal line overlap, electromagnetic waves generated from the signal line are radiated from the gap, which is prevented.

Further, the number of divisions of the power supply conductor layer can be reduced, and the number of inductance elements for connecting the divided power supply conductors can be reduced. For example, in FIG. 3, four power supply conductor layers 2 of (A) to (D)
0 are connected by an inductance element 6. If the signal lines are laid only in the area where the power supply conductor layers 20 of (A) and (C) are arranged, the power supply conductor layers 20 of (A) and (D) become unnecessary. be able to.
In FIG. 6, the power supply conductor layer 20 is moved to one side, but the shape of the wiring board, including the vertical and horizontal directions, is not limited.

As described above, in the second embodiment, the power supply conductor layer is provided only in the region where the signal line is located in the signal line layer sandwiched between the ground conductor layer and the power supply conductor layer. This makes it possible to obtain a printed wiring board capable of reducing electromagnetic interference and radiated noise on the outside of the substrate and on a layer closer to the outside of the substrate than the conductor layer, such as crosstalk between lines. Further, the effect of suppressing radiation noise can be enhanced. Further, the number of inductance elements for connecting the divided power supply conductor layers can be reduced.

Embodiment 3 FIG. FIG. 8 is a cross-sectional view for describing a printed wiring board according to Embodiment 3. In FIG. 8, the signal wiring 30 disposed between the power supply conductor layer 20 and the ground conductor layer 1 is a high-speed signal line 31.
In addition, a signal line 32 for a low-speed signal may be included. A high-speed signal line is a signal line in a frequency band in which electromagnetic coupling between adjacent signal lines occurs. Conversely, a low-speed signal line is a signal line in a frequency band in which electromagnetic coupling between adjacent signal lines does not occur. Here, in the signal wiring 30 between the power supply conductor layer 20 and the ground conductor layer 1, the power supply conductor layer 20 is provided only in a range where the high-speed signal line 31 is arranged. Thereby, the area of the power supply conductor layer 20 can be reduced, and the resonance frequency can be shifted to a higher one.
The radiation efficiency in a frequency band lower than the resonance frequency is degraded, and the radiation noise suppression effect can be enhanced. The high-speed signal line 31 is disposed at least one pattern width inside the power supply conductor layer 20 in the same manner as in the second embodiment. This is to prevent the gap and the signal line from overlapping with each other along the gap formed between the divided power supply conductor layers 20. When the gap and the signal line overlap, electromagnetic waves generated from the signal line are radiated from the gap, which is prevented. Further, since the number of divided power supply conductor layers can be reduced, the number of inductance elements for connecting the divided power supply conductor layers can be reduced. In FIG. 8, the power supply conductor layer 20 is shifted to one side, but the shape of the wiring board, including the vertical and horizontal directions, is not limited. Further, a configuration in which a block in which high-speed signal lines 31 are collected and a block in which low-speed signal lines 32 are collected is also included. By separating the block in which the high-speed signal lines 31 are collected and the block in which the low-speed signal lines 32 are collected, the electromagnetic coupling between the high-speed signal lines 31 and the low-speed signal lines 32 can be suppressed. The low-speed signal line 32 includes a power supply line of a type different from the analog signal line and the power supply conductor layer 20 and a ground line of a type different from the ground conductor layer 1.

As described above, in the third embodiment, the power supply conductor layer is provided only in the range where the high-speed signal lines are wired. This makes it possible to obtain a printed wiring board capable of reducing electromagnetic interference and radiated noise on the outside of the substrate and on a layer closer to the outside of the substrate than the conductor layer, such as crosstalk between lines. Further, the effect of suppressing radiation noise can be enhanced. In addition, the number of inductance elements for connecting the divided power supply conductor layers can be reduced. Further, electromagnetic coupling between the high-speed signal line and the low-speed signal line can be suppressed.

Embodiment 4 FIG. 9 is a cross-sectional view for describing a printed wiring board according to Embodiment 4. As shown in FIG. 9, here, only the high-speed signal line 31 is disposed between the power supply conductor layer 20 and the ground conductor layer 1, and the low-speed signal line is disposed between the power supply conductor layer 20 and the ground conductor layer 1. 1 is disposed on a layer closer to the outside of the substrate, for example, the signal conductor layer 4.

As described above, in the fourth embodiment,
In a printed wiring board having a structure in which a signal line is sandwiched between a ground conductor layer and a power conductor layer, the power conductor layer is divided,
Further, the divided power supply conductor layers were connected by an inductance element, and only the high-speed signal lines were laid out on the signal line layer sandwiched between the ground conductor layer and the power supply conductor layer.

As described above, by arranging the high-speed signal line and the low-speed signal line in different layers, the performance of suppressing the electromagnetic coupling between the high-speed signal line 31 and the low-speed signal line can be improved. Also, when designing the board, the isolation between the high-speed signal line and the low-speed signal line is structurally ensured, so there is no need to consider again the arrangement of the high-speed signal line and the low-speed signal line in the same layer when designing the board. It is possible to shorten the period for designing the substrate and reduce the design load.

Embodiment 5 FIG. FIG. 10 is a cross-sectional view for describing a printed wiring board according to Embodiment 5. As shown in FIG. 10, here, only the high-speed signal line 31 is provided between the power supply conductor layer 20 and the ground conductor layer 1, and the low-speed signal line is connected to the power supply conductor layer 20.
And a layer of the conductor layer 1 for ground closer to the outside of the substrate, for example,
It was arranged on the signal conductor layer 4. Further, the power supply conductor layer 20 was provided only in a range where the high-speed signal line 31 was disposed between the power supply conductor layer 20 and the ground conductor layer 1.

As described above, in the fifth embodiment,
The power supply conductor layer was provided only in the region where the high-speed signal line was located.

As described above, the performance of suppressing the electromagnetic coupling between the high-speed signal line and the low-speed signal line can be improved. Also,
Since the isolation between the high-speed signal line and the low-speed signal line is structurally ensured when designing the board, it is not necessary to consider again the arrangement of the high-speed signal line and the low-speed signal line in the same layer when designing the board. Further, the area of the power supply conductor layer 20 can be reduced, and the effect of suppressing radiation noise can be enhanced. Further, the number of divided power supply conductor layers can be reduced, and the number of inductance elements for connecting the divided power supply conductor layers can be reduced.

Embodiment 6 FIG. FIG. 11 is a cross-sectional view for describing a printed wiring board according to Embodiment 6. In the printed wiring boards described in the first to fifth embodiments, the signal wiring 30 sandwiched between the grounding conductor layer 1 and the power supply conductor layer 20 has a gap 29 (between the divided power supply conductor layers 20). The gap 29 is hereinafter referred to as a slit 29) so that the slit 29 and the signal wiring 30 do not overlap. When the signal wiring 30 overlaps with the slit 29 along the slit 29, the signal wiring 30 must be at least one pattern width wide (one pattern width is the width x of the signal wiring 30). (To be shifted inward) means that the distance from the end of the power supply conductor layer 20 to the end of the signal wiring 30 is y (x <y), where x is the width of the signal line. ) The signal lines do not overlap along the slit 29.

As described above, in the sixth embodiment,
The signal lines sandwiched between the ground conductor layer and the power supply conductor layer were laid out so that the slits between the divided power supply conductor layers did not overlap the slits along the slits.

As described above, it is possible to prevent the isolation between the signal wire 30 and the signal conductor layer 4 or the isolation between the signal wire 30 and the outside of the substrate from being deteriorated in the slit portion.

Embodiment 7 FIG. 12 is a cross-sectional view for describing a printed wiring board according to Embodiment 7. As shown in FIG. 12, in the printed wiring board according to the first to sixth embodiments, the signal wiring 30 sandwiched between the ground conductor layer 1 and the power supply conductor layer 20 (in the seventh embodiment, the signal wiring 30 Therefore, the signal wiring 30 is referred to as a high-speed signal line 30), and the low-speed signal line 40 in a layer closer to the outside of the substrate with the power supply conductor layer 20 interposed therebetween.
And the slit 29 does not overlap with the slit 29 along the slit 29. When the high-speed signal line 30 or the high-speed signal line 30 and the low-speed signal line 40 are in a positional relationship overlapping with the slit 29, the high-speed signal line 30 is moved from the end of the power supply conductor layer 20 by y (x <y, where x is shifted inward by the width of the high-speed signal line) so that the signal line is separated from the slit 29 by one pattern width or more.

As shown in the sectional view of FIG. 13 and the top perspective view of FIG. 14, the slit 29 is formed in a layer where the low-speed signal line 40 and at least one of the high-speed signal line 30d and the high-speed signal line 30e are different. In some cases, wiring is performed so as to be perpendicular to the wiring, and at least one of the high-speed signal line 30d and the high-speed signal line 30e is overlapped with the low-speed signal line 40. In this case, FIG.
15, the high-speed signal lines 30d and 30e are arranged at positions separated from the low-speed signal line 40 by a distance y as shown in FIG. I do. High-speed signal lines 30d and 30e
Are assumed to have a signal line width x and x <y.

As described above, in the seventh embodiment,
A signal line sandwiched between the ground conductor layer and the power supply conductor layer and a signal line wired on a layer closer to the outside of the substrate than the power supply conductor layer are formed between the divided power supply conductor layers. A layout is made along the slit so that it does not overlap with the slit.

As described above, it is possible to prevent the isolation between the high-speed signal line and the low-speed signal line from deteriorating at the slit.

Embodiment 8 FIG. In the printed wiring boards according to the first to seventh embodiments, an inductance element is used for connection between the divided power supply conductor layers. However, instead of the inductance element, connection may be made by a conductor on the component mounting surface or by a pattern on the power supply conductor layer. FIG. 16 shows a diagram in which the divided power supply conductor layers 20 are connected by conductors 60. In FIG. 16, the signal conductor layer 4 also serves as a component mounting surface for mounting components together with signal lines. The conductor 60 is mounted on the signal conductor layer 4, and is provided with a conductor wire 50 such as a through hole via a pad 61.
Is connected to the end. Conductor wire 50 such as through hole
Is connected to the power supply conductor layer 20 at an end different from the end connected to the pad 61, and the divided power supply conductor layer 20
Are connected. FIG. 17 shows the divided power supply conductor layer 20.
Are connected by changing the shape pattern. The power supply conductor layer 20 shown in FIG. 17 is formed by processing a part of the shape, for example, making the power supply conductor layer thinner as indicated by D, and connecting the power supply conductor layers 21 and 22. I have.

As described above, in the eighth embodiment,
The divided power supply conductor layers were connected not by inductance elements but by conductors such as patterns.

For this reason, the radiation noise suppressing effect is deteriorated. However, if the deterioration is within an allowable range, it is not necessary to use the component mounting surface of the substrate for the connection between the power supply conductor layers. Can be lowered. Alternatively, the mounting area on the substrate can be increased and the manufacturing cost can be reduced.

[0040]

As described above, according to the printed wiring board of the present invention, in a printed wiring board having a structure in which a signal line is sandwiched between a ground conductor layer and a power supply conductor layer, the power supply conductor layer is divided. The above-mentioned divided power supply conductor layers are connected by conductors. Therefore, there is an effect that radiation noise generated from the signal line can be suppressed. Also, for example, by setting the conductor connecting the divided power supply conductor layers to a conductor generated by changing a part of the shape of the power supply conductor layer, the component mounting of the board is performed for the connection between the power supply conductor layers. Eliminates the need to use surfaces. Therefore, there is an effect of reducing the manufacturing cost.

Further, the divided power supply conductor layers were connected by an inductance element including a magnetic material penetrating type conductor such as a ferrite bead. This changes the resonance frequency of the parallel plate formed by the ground conductor layer and the power supply conductor layer in the mode fed by the signal line, or causes an electromagnetic field induced between the ground conductor layer and the power supply conductor layer. , The radiation noise can be reduced. Therefore, there is an effect that a printed wiring board capable of reducing external electromagnetic interference and radiation noise such as crosstalk between lines can be obtained.

Further, the power supply conductor layer is arranged in a region where the signal line is wired. For this reason, the number of divisions of the power supply conductor layer can be reduced, and the number of inductance elements connecting the divided power supply conductor layers can be reduced.
Therefore, there is an effect that the manufacturing cost can be reduced.

Further, the power supply conductor layer is arranged in a region where the signal lines in which at least electromagnetic coupling between adjacent signal lines occurs in a specific frequency band are arranged. For this reason, the number of divisions of the power supply conductor layer can be reduced, and the number of inductance elements connecting the divided power supply conductor layers can be reduced. Therefore, there is an effect that the manufacturing cost can be reduced.

Further, the signal lines were routed along the gaps between the divided power supply conductor layers at positions not overlapping with the gaps. Therefore, there is an effect that it is possible to prevent the isolation between the signal line sandwiched between the power supply conductor layer and the ground conductor layer and the signal lines other than the signal line from deteriorating.

Further, the signal lines sandwiched between the power supply conductor layer and the ground conductor layer and other signal lines were wired along the gaps between the divided power supply conductor layers so as not to overlap the gaps. Therefore, there is an effect that it is possible to prevent the isolation between the signal line sandwiched between the power supply conductor layer and the ground conductor layer and the signal lines other than the signal line from deteriorating.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a printed wiring board having a laminated structure according to the present invention.

FIG. 2 is a diagram showing a layer configuration of the printed wiring board having a laminated structure shown in FIG. 1;

FIG. 3 is a plan view for explaining the printed wiring board according to the first embodiment;

FIG. 4A is a diagram A of FIG. 3 for explaining connection between power supply conductor layers in the printed wiring board according to the first embodiment;
Sectional drawing in -A. FIG. 4B is a detailed view of a conductor penetrating the ferrite beads of FIG.

FIG. 5 is a sectional view taken along line BB of FIG. 3 for describing the printed wiring board according to the first embodiment;

FIG. 6 is a sectional view illustrating a printed wiring board according to a second embodiment;

FIGS. 7A and 7B are cross-sectional views illustrating a resonance frequency according to the second embodiment.

FIG. 8 is a sectional view illustrating a printed wiring board according to a third embodiment;

FIG. 9 is a cross-sectional view illustrating a printed wiring board according to a fourth embodiment.

FIG. 10 is a cross-sectional view illustrating a printed wiring board according to a fifth embodiment.

FIG. 11 is a cross-sectional view illustrating a printed wiring board according to a sixth embodiment.

FIG. 12 is a cross-sectional view illustrating a printed wiring board according to a seventh embodiment.

FIG. 13 is a cross-sectional view illustrating a printed wiring board according to a seventh embodiment.

FIG. 14 is a top perspective view for explaining a printed wiring board according to a seventh embodiment.

FIG. 15 is a top perspective view for describing a printed wiring board according to a seventh embodiment.

FIG. 16 is a cross-sectional view illustrating a printed wiring board according to Embodiment 8;

FIG. 17 is a plan view illustrating a printed wiring board according to an eighth embodiment.

FIG. 18 is a plan view showing a conventional printed wiring board.

[Explanation of symbols]

1 conductor layer for ground, 2 conductor layer for power supply, 3, 4
Signal conductor layer, 5 dielectric layer, 6 inductance element, 20, 21, 22 divided power supply conductor layer, 29
Gap (slit), 30, 30a, 30b, 30d, 3
0e signal wiring, high-speed signal line, 30c signal line, 31
High-speed signal line, 32 low-speed signal line, 40 low-speed signal line, 5
0 Conductor wires such as through holes, 51 conductors penetrating ferrite beads, 52, 60 conductors, 53 ferrite beads, 61 pads, 100 power supply or ground layer of printed wiring board, 101 opening.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Mitsuhiko Kanda, 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Katsumi Toyama 2-3-2, Marunouchi, Chiyoda-ku, Tokyo Rishi Electric Co., Ltd. (72) Inventor Yu Uchida 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Hideki Tsuruse 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Inside the corporation

Claims (7)

[Claims] 1. A printed wiring board having a laminated structure in which a signal line is sandwiched between a conductor layer for ground and a conductor layer for power supply, wherein the power supply conductor layer is divided into a plurality of parts, and the divided power supply conductor layer is formed of a conductor. A printed wiring board having a laminated structure, characterized in that the printed wiring board is connected by: 2. The printed wiring board according to claim 1, wherein the conductor connecting the divided power supply conductor layers is an inductance element. 3. The printed wiring board according to claim 1, wherein the power supply conductor layer is arranged in a region where the signal line is wired. 4. The signal line, wherein at least electromagnetic coupling between adjacent signal lines occurs in a specific frequency band, and the power supply conductor layer has a region where the signal line is wired. 4. The printed wiring board having a laminated structure according to claim 3, wherein 5. The signal line according to claim 1, wherein the signal line is not arranged at a position where the signal line is arranged and overlaps with the gap along a gap formed between the divided power supply conductor layers. 4. A printed wiring board having a laminated structure according to any one of the above items 4. 6. The printed wiring board having the laminated structure further includes a signal line disposed on a layer disposed outside the printed wiring board with respect to the power supply conductor layer. The signal line sandwiched between the power supply conductor layers and the signal line wired in a layer disposed on the outer side of the printed wiring board with respect to the power supply conductor layer are located between the divided power supply conductor layers. The printed wiring board having a laminated structure according to any one of claims 1 to 3, wherein the wiring is not arranged at a position overlapping the gap along a gap that can be formed. 7. The printed wiring board according to claim 2, wherein the inductance element is at least a ferrite bead.