JP6362419B2 - Printed circuit board - Google Patents

Description

  The present invention relates to a printed circuit board having wiring and a ground surface.

  2. Description of the Related Art Conventionally, printed circuit boards in which electronic components and wirings connected to the electronic components are mounted on a substrate are used in control circuits for setting the state of equipment. There is also known a printed circuit board having a function of letting a current flowing in the wiring due to static electricity escape to the ground side (see, for example, Patent Document 1 and Patent Document 2).

  In the printed circuit board of Patent Document 1, the width of the gap (gap portion) provided between the pattern (first conductor pattern) formed on the substrate and the pattern (second conductor pattern) connected to the ground (ground) side is set. , Only a part is formed narrow (0.15 mm width). Thereby, static electricity is released to the ground side through the gap, and the semiconductor of the block connected to the first conductor pattern is prevented from being destroyed. Similarly, in the wiring board of Patent Document 2, a part of a conductor pattern connected between electronic components is brought close to a ground (GND) conductor pattern to discharge static electricity to the GND conductor pattern.

JP-A-5-67851 JP 2001-7455 A

  In the conventional printed circuit board, since static electricity is directly released to the ground side through the gap, a large current flows in the current path on the ground side. Therefore, there has been a problem that radiation noise is generated from the current path on the ground side. Further, there is a problem that an instantaneous overvoltage (so-called “spike”) occurs in a signal voltage such as a state setting signal or a DC power supply signal flowing through the wiring after the static electricity is released to the ground side.

  The present invention has been made to solve the above-described problems, and can suppress radiation noise from the current path on the ground side, and can suppress spikes in the signal voltage of the signal flowing through the wiring. An object of the present invention is to provide a printed circuit board capable of performing

  The printed circuit board of the present invention includes a wiring disposed in the first layer of the substrate and connected to the component, a first conductor disposed in the first layer and adjacent to the wiring through the gap, A second conductor disposed on the first layer and electrically grounded; and a filter part disposed on the first layer and interposed between the first conductor and the second conductor. is there.

  According to the printed circuit board of the present invention, the radiation noise from the current path on the ground side can be suppressed, and the spike of the signal voltage of the signal flowing through the wiring can be suppressed.

It is explanatory drawing which looked at the printed circuit board circuit of Embodiment 1 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 1 of this invention from the A-A 'cross section. It is explanatory drawing which looked at the printed circuit board of Embodiment 2 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 2 of this invention from the A-A 'cross section. It is explanatory drawing which looked at the printed circuit board of Embodiment 3 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 3 of this invention from the A-A 'cross section. It is explanatory drawing which looked at the printed circuit board of Embodiment 4 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 4 of this invention from the A-A 'cross section. It is explanatory drawing which looked at the printed circuit board of Embodiment 5 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 6 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 7 of this invention from the upper surface. It is explanatory drawing which looked at the printed circuit board of Embodiment 8 of this invention from the upper surface.

Embodiment 1 FIG.
A printed circuit board according to Embodiment 1 of the present invention will be described with reference to FIGS.
In the figure, 19 is a substrate. The substrate 19 is made of a plate-like dielectric. An electronic component (component) 20 such as a transistor to be protected from static electricity is mounted on the first layer 191 of the substrate 19. In addition, the wiring 12 made of a conductor connected to the electronic component 20 is disposed on the first layer 191.

  A first conductor 13 is provided adjacent to the wiring 12 via a gap 22. A capacitor (capacitance element) 14 and a resistance element 15 connected in series are interposed between the first conductor 13 and the second conductor 16. The first conductor 13, the capacitor 14, the resistance element 15, and the second conductor 16 are disposed on the first layer 191 of the substrate 19. The capacitor 14 and the resistor element 15 constitute a filter component part.

  A ground surface 18 made of a ground conductor is provided on the second layer 192 of the substrate 19 facing the first layer 191. The second conductor 16 is connected to the ground surface 18 via a via 17 made of a conductor rod that penetrates the substrate 19 and is electrically grounded. The first conductor 13, the capacitor 14, the resistor element 15, the second conductor 16, the via 17, and the ground plane 18 constitute a current path on the ground (earth) side.

The operation of the printed circuit board 11 configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the current path on the ground side, and finally flows to the ground surface 18 via the via 17.

  At this time, since the capacitor 14 and the resistor element 15 are mounted, the discharge current flowing through the ground-side current path is reduced. Therefore, radiation noise from the ground-side current path can be suppressed. In addition, since the capacitor 14 and the resistor element 15 serve as a protection circuit against overvoltage (so-called “snubber circuit”), the spike of the signal voltage of the signal flowing through the wiring 12 can be suppressed.

As described above, in the printed circuit board 11 according to the first embodiment, the filter component portion including the capacitor 14 and the resistance element 15 is interposed between the first conductor 13 and the second conductor 16.
Thereby, radiation noise from the current path on the ground side can be suppressed, and spikes in the signal voltage of the signal flowing through the wiring can be suppressed.

  Although the printed circuit board 11 is a two-layer board composed of one board 19, the number of layers may be any number. A wiring, a first conductor, a second conductor, and a filter component portion are provided in any layer of the multilayer substrate, and the ground surface and the second conductor provided in any other layer are connected through a through hole made of a hollow conductor. It may be connected.

  Further, a conductor pattern other than the wiring 12 may be provided on the first layer 191. Furthermore, other semiconductor elements and electronic components other than the electronic component 20 may be mounted.

  1 and 2 show that the first conductor 13 and the second conductor 16 are each formed of a rectangular parallelepiped conductor, but are not limited to this shape.

Embodiment 2. FIG.
A printed circuit board in which three elements are provided in the filter component section will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11 of Embodiment 1 shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

In the figure, 21 is an inductor (inductive element). Between the first conductor 13 and the second conductor 16, a capacitor 14, a resistance element 15 and an inductor 21 connected in series are interposed. The capacitor 14, the resistance element 15, and the inductor 21 constitute a filter component part.
The first conductor 13, the capacitor 14, the resistance element 15, the inductor 21, the second conductor 16, the via 17, and the ground plane 18 constitute a ground-side current path.

The operation of the printed circuit board 11a configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the current path on the ground side, and finally flows to the ground surface 18 via the via 17.

  At this time, since the capacitor 14, the resistance element 15, and the inductor 21 are mounted, the discharge current flowing through the current path on the ground side becomes small. Therefore, radiation noise from the ground-side current path can be suppressed. In addition, since the capacitor 14, the resistance element 15, and the inductor 21 serve as a snubber circuit, spikes in the signal voltage of the signal flowing through the wiring 12 can be suppressed.

As described above, in the printed circuit board 11 a according to the second embodiment, the filter component portion including the capacitor 14, the resistance element 15, and the inductor 21 is interposed between the first conductor 13 and the second conductor 16.
Thereby, radiation noise from the current path on the ground side can be suppressed, and spikes in the signal voltage of the signal flowing through the wiring can be suppressed.

  Instead of the inductor 21, a ferrite bead (so-called “ferrite bead inductor”) having a conductor wire inside may be mounted.

Embodiment 3 FIG.
A printed circuit board in which one element is provided in the filter component section will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11 of Embodiment 1 shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

  A resistance element 15 is interposed between the first conductor 13 and the second conductor 16. The filter element portion is configured by the resistance element 15. The first conductor 13, the resistance element 15, the second conductor 16, the via 17, and the ground surface 18 constitute an earth-side current path.

The operation of the printed circuit board 11b configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the current path on the ground side, and finally flows to the ground surface 18 via the via 17.

  At this time, since the resistance element 15 is mounted, the discharge current flowing through the ground-side current path is reduced. Therefore, radiation noise from the ground-side current path can be suppressed.

As described above, in the printed circuit board 11 b according to the third embodiment, the filter component portion including the resistance element 15 is interposed between the first conductor 13 and the second conductor 16.
Thereby, radiation noise from the current path on the ground side can be suppressed.

  A configuration in which a ferrite bead inductor is mounted instead of the resistance element 15 may be adopted.

Embodiment 4 FIG.
A printed circuit board provided with a first conductor, a second conductor, and a filter component portion on both sides of the wiring will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11 of Embodiment 1 shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

A first conductor 13a is provided adjacent to a side portion of the wiring 12 that faces the gap portion 22 via a gap portion 22a. A capacitor (capacitance element) 14a and a resistance element 15a connected in series are interposed between the first conductor 13a and the second conductor 16a. The first conductor 13 a, the capacitor 14 a, the resistance element 15 a, and the second conductor 16 a are provided on the first layer 191 of the substrate 19.
A filter component section is constituted by the capacitor 14a and the resistance element 15a.

The second conductor 16a is connected to the ground surface 18 via a via 17a made of a conductor rod that penetrates the substrate 19, and is electrically grounded.
Here, the first conductor 13, the capacitor 14, the resistance element 15, the second conductor 16, the via 17, and the ground plane 18 constitute a first current path on the ground side. Similarly, the first conductor 13a, the capacitor 14a, the resistance element 15a, the second conductor 16a, the via 17a, and the ground surface 18 constitute a second current path on the ground side.

The operation of the printed circuit board 11c configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the first current path on the ground side, and finally flows to the ground plane 18 via the via 17.
In addition, the current flowing through the wiring 12 due to static electricity is discharged to the first conductor 13a adjacent thereto via the gap 22a. The discharge current sequentially flows from the first conductor 13a through the second current path on the ground side, and finally flows to the ground surface 18 through the via 17a.

At this time, since the capacitor 14 and the resistance element 15 are mounted, the discharge current flowing through the first current path on the ground side becomes small. Further, since the capacitor 14a and the resistance element 15a are mounted, the discharge current flowing through the second current path on the ground side becomes small. Therefore, radiation noise from the first current path and the second current path on the ground side can be suppressed.
In addition, since the capacitor 14 and the resistor element 15 and the capacitor 14a and the resistor element 15a each function as a snubber circuit, spikes in the signal voltage of the signal flowing through the wiring 12 can be suppressed.

As described above, in the printed circuit board 11 c according to the fourth embodiment, the filter component portion including the capacitor 14 and the resistance element 15 is interposed between the first conductor 13 and the second conductor 16.
In addition, a filter component portion including a capacitor 14a and a resistance element 15a is interposed between the first conductor 13a and the second conductor 16a.
Thereby, radiation noise from the current path on the ground side can be suppressed, and the occurrence of spikes in the signal voltage of the signal flowing through the wiring can be suppressed.

  7 and 8, the arrangement of the first conductor 13a, the capacitor 14a, the resistive element 15a, and the second conductor 16a is such that the first conductor 13, the capacitor 14, the resistive element 15 and the second conductor 16a with the wiring 12 as the target axis. Although the conductor 16 and the conductor 16 are shown to be line symmetrical, the arrangement is not limited to this.

  The first conductor 13 and the first conductor 13a may be different conductors, and the second conductor 16 and the second conductor 16a may be different conductors.

  Also, the filter parts on both sides of the wiring 12 may use different elements. Each filter component unit may have any one of the filter component units described in the second embodiment or the third embodiment.

Embodiment 5. FIG.
With reference to FIG. 9, a printed circuit board in which two elements are provided in the filter component section will be described. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11 of Embodiment 1 shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

  A capacitor 14 and a resistance element 15 connected in parallel are interposed between the first conductor 13 and the second conductor 16. The capacitor 14 and the resistor element 15 constitute a filter component part.

  The first conductor 13, the capacitor 14, the second conductor 16, the via 17, and the ground plane 18 constitute a first current path on the ground side. The first conductor 13, the resistance element 15, the second conductor 16, the via 17, and the ground surface 18 constitute a second current path on the ground side.

The operation of the printed circuit board 11d configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the first current path and the second current path on the ground side, and finally flows through the via 17 to the ground surface 18.

  At this time, since the capacitor 14 is mounted, the discharge current flowing through the first current path on the ground side becomes small. By mounting the resistance element 15, the discharge current flowing through the second current path on the ground side becomes small. Therefore, radiation noise from the first current path and the second current path on the ground side can be suppressed.

As described above, in the printed circuit board 11 d according to the fifth embodiment, the filter component portion including the capacitor 14 and the resistance element 15 is interposed between the first conductor 13 and the second conductor 16.
Thereby, radiation noise from the current path on the ground side can be suppressed.

  Instead of the resistance element 15, an inductive element or a ferrite bead inductor may be mounted.

Embodiment 6 FIG.
A printed circuit board in which three elements are provided in the filter component section will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11 of Embodiment 1 shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

  A capacitor 14 and a capacitor 23 are connected in series between the first conductor 13 and the second conductor 16. A resistive element 15 is connected in parallel to the capacitor 14 and the capacitor 23. The capacitor 14, the capacitor 23, and the resistance element 15 constitute a filter component unit.

  The first conductor 13, the capacitor 14, the capacitor 23, the second conductor 16, the via 17, and the ground plane 18 constitute a first current path on the ground side. The first conductor 13, the resistance element 15, the second conductor 16, the via 17, and the ground surface 18 constitute a second current path on the ground side.

The operation of the printed circuit board 11e configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the first current path and the second current path on the ground side, and finally flows through the via 17 to the ground surface 18.

  At this time, since the capacitor 14 and the capacitor 23 are mounted, the discharge current flowing through the first current path on the ground side becomes small. By mounting the resistance element 15, the discharge current flowing through the second current path on the ground side becomes small. Therefore, radiation noise from the first current path and the second current path on the ground side can be suppressed.

  In addition, when the static electricity is at a high voltage, the capacitor of the filter component part may be electrically short-circuited to cause a so-called “short failure”. On the other hand, by mounting a plurality of capacitors 14 and 23 in series, it is possible to withstand a high voltage and prevent a short circuit failure.

As described above, the printed circuit board 11e according to the sixth embodiment has a plurality of capacitors 14 and 23 connected in series between the first conductor 13 and the second conductor 16, and the capacitors 14 and 23. A filter component part comprising a resistive element 15 connected in parallel is interposed.
Thereby, radiation noise from the current path on the ground side can be suppressed, and a short circuit failure of the capacitors 14 and 23 due to a high voltage can be prevented.

  Instead of the resistance element 15, an inductive element or a ferrite bead inductor may be mounted. Instead of the two capacitors 14 and 23, a configuration in which n (n is a natural number of 3 or more) capacitors are mounted in series may be employed.

Embodiment 7 FIG.
A printed circuit board in which two elements are provided in the filter component section will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11 of Embodiment 1 shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

  A resistance element 15 and a resistance element 24 connected in parallel are interposed between the first conductor 13 and the second conductor 16. The filter element portion is configured by the resistance element 15 and the resistance element 24.

  The first conductor 13, the resistance element 15, the second conductor 16, the via 17, and the ground surface 18 constitute a first current path on the ground side. The first conductor 13, the resistance element 24, the second conductor 16, the via 17, and the ground surface 18 constitute a second current path on the ground side.

The operation of the printed circuit board 11f configured as described above will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the first current path and the second current path on the ground side, and finally flows through the via 17 to the ground surface 18.

  At this time, since the resistance element 15 is mounted, the discharge current flowing through the first current path on the ground side becomes small. By mounting the resistance element 24, the discharge current flowing through the second current path on the ground side is reduced. Therefore, radiation noise from the first current path and the second current path on the ground side can be suppressed.

  Further, when the voltage applied to the resistance element of the filter part is a high voltage, the resistance element may fail. On the other hand, the current flowing through the resistance elements 15 and 24 can be shunted by mounting the plurality of resistance elements 15 and 24 in parallel. Therefore, it is possible to withstand a high voltage and prevent the resistance elements 15 and 24 from failing.

As described above, in the printed circuit board 11 f according to the seventh embodiment, the filter component portion including the resistance element 15 and the resistance element 24 is interposed between the first conductor 13 and the second conductor 16.
Thereby, radiation noise from the current path on the ground side can be suppressed, and failure of the resistance elements 15 and 24 due to high voltage can be prevented.

  Instead of the resistance elements 15 and 24, an inductive element or a ferrite bead inductor may be mounted. Instead of the two resistance elements 15 and 24, m (m is a natural number of 3 or more) resistance elements may be mounted in parallel.

Embodiment 8 FIG.
With reference to FIG. 12, a printed circuit board in which a component protecting element is provided on the wiring will be described. In addition, the same code | symbol is attached | subjected to the structural member similar to the printed circuit board 11f of Embodiment 7 shown in FIG. 11, and description is abbreviate | omitted.

  A resistance element (component protection resistance element) 25 is mounted in series with the wiring 12. Between the first conductor 13 and the second conductor 16, a filter component portion composed of a resistance element 15 and a resistance element 24 connected in parallel is interposed.

  The first conductor 13, the resistance element 15, the second conductor 16, the via 17, and the ground surface 18 constitute a first current path on the ground side. The first conductor 13, the resistance element 24, the second conductor 16, the via 17, and the ground surface 18 constitute a second current path on the ground side.

The operation of the thus configured printed circuit board 11g will be described.
The electric current that has flowed through the wiring 12 due to static electricity is discharged to the first conductor 13 provided adjacently via the gap 22. The discharge current sequentially flows from the first conductor 13 through the first current path and the second current path on the ground side, and finally flows through the via 17 to the ground surface 18.

  At this time, by mounting the resistance element 25 in series with the wiring 12, the electronic component 20 can be protected from a current caused by static electricity.

  In addition, since the resistance element 15 is mounted, the discharge current flowing through the first current path on the ground side is reduced. By mounting the resistance element 24, the discharge current flowing through the second current path on the ground side is reduced. Therefore, radiation noise from the first current path and the second current path on the ground side can be suppressed.

As described above, the printed circuit board 11 g according to the eighth embodiment has the resistance element 25 mounted in series with the wiring 12. Between the first conductor 13 and the second conductor 16, a filter component portion composed of a resistance element 15 and a resistance element 24 connected in parallel is interposed.
Thereby, the electronic component 20 can be protected from the electric current by static electricity, and the radiation noise from the earth-side current path can be suppressed.

  Instead of the resistance element 25, an inductive element (component protecting inductive element) or a ferrite bead inductor (component protecting ferrite bead inducting element) may be mounted.

  In the present invention, within the scope of the invention, any combination of the embodiments, or any modification of any component in each embodiment, or omission of any component in each embodiment is possible. .

  11, 11a, 11b, 11c, 11d, 11e, 11f, 11g Printed circuit board, 12 wiring, 13, 13a first conductor, 14, 14a capacitor (capacitance element), 15, 15a resistance element, 16, 16a second conductor 17, 17a Via, 18 Ground plane, 19 Substrate, 20 Electronic component (component), 21 Inductor (inductive element), 22, 22a Gap, 23 Capacitor (capacitance element), 24 Resistive element, 25 Resistive element (component protection) Resistance element).

Claims (16)

Wiring disposed on the first layer of the substrate and connected to the component;
A first conductor disposed in the first layer and adjacent to the wiring via a gap;
A second conductor disposed in the first layer and electrically grounded;
A filter part disposed in the first layer and interposed between the first conductor and the second conductor;
A printed circuit board comprising: It said second conductor is a printed circuit board according to claim 1, wherein the through conductor rod penetrating the substrate are connected to the ground conductor provided on the second layer of the substrate.   The printed circuit board according to claim 1, wherein the filter component unit includes a capacitor element and a resistor element connected in series.   The printed circuit board according to claim 1, wherein the filter component unit includes a capacitive element, a resistive element, and an inductive element connected in series.   3. The printed circuit board according to claim 1, wherein a capacitor element, a resistance element, and a ferrite bead induction element are connected in series to the filter component unit.   The printed circuit board according to claim 1, wherein the filter component unit is a resistance element or a ferrite bead induction element.   The printed circuit board according to claim 1, wherein the filter component section includes a capacitor element and a resistor element connected in parallel.   3. The printed circuit board according to claim 1, wherein a capacitor element and a ferrite bead induction element are connected in parallel to the filter component unit. 4.   The printed circuit board according to claim 1, wherein the filter component unit includes a capacitor element and an inductive element connected in parallel.   The printed circuit board according to claim 1, wherein the filter component unit includes a plurality of capacitive elements connected in series, and a resistive element connected in parallel to the capacitive element.   The printed circuit board according to claim 1, wherein the filter component unit includes a plurality of resistance elements connected in parallel.   The printed circuit board according to claim 1, wherein a component protection resistance element is connected to the wiring.   The printed circuit board according to claim 1, wherein an inductive element for component protection is connected to the wiring.   The printed circuit board according to any one of claims 1 to 11, wherein a ferrite bead induction element for component protection is connected to the wiring. The printed circuit according to claim 1, wherein the first conductor, the second conductor, and the filter component portion are provided on both sides of the wiring. substrate. 16. The filter component portion provided on one side with respect to the wiring and the filter component portion provided on the other side with respect to the wiring are configured by different elements. Printed circuit board.

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