WO2017033950A1

WO2017033950A1 - Electronic circuit substrate

Info

Publication number: WO2017033950A1
Application number: PCT/JP2016/074586
Authority: WO
Inventors: 達也福永
Original assignee: Tdk株式会社
Priority date: 2015-08-26
Filing date: 2016-08-24
Publication date: 2017-03-02
Also published as: JPWO2017033950A1

Abstract

Provided is an electronic circuit substrate capable of reducing equivalent series inductance, which is the parasitic inductance of a capacitor or the inductance of the wiring of a mounting substrate. An electronic circuit substrate 1 having a capacitor 104 and a mounting substrate 111 that has a DC power source layer and a ground layer, the electronic circuit substrate 1 being characterized in that the capacitor 104 is mounted onto the mounting substrate 111 by being connected to the DC power source layer and the ground layer via wiring 103a, 103b, in that a first inductor, which is the parasitic inductor component of the capacitor 104, and a second inductor, which is the inductor component for the wiring 103a, 103b, are connected in series, and by also having a closed conductor loop for magnetically coupling with the first inductor and/or the second inductor.

Description

Electronic circuit board

The present invention relates to an electronic circuit board.

In recent years, a CPU (main processing unit) used in an information processing apparatus has an increased operating frequency and a significantly increased current consumption due to an improvement in processing speed and higher integration. Along with this, the operating voltage tends to decrease in order to reduce the power consumption. Accordingly, in the power supply for supplying power to the CPU, a large current fluctuation (noise current) occurs at a higher speed, and it is very difficult to suppress the voltage fluctuation accompanying the current fluctuation within the allowable value of the power supply. became. For this reason, a multilayer capacitor as a smoothing capacitor is arranged around the CPU so as to be connected to a power supply, and is frequently used as a countermeasure for stabilizing the power supply. In other words, the current is supplied from the multilayer capacitor to the CPU by quick charge / discharge when the current fluctuates at a high speed, thereby suppressing the voltage fluctuation of the power source.

As the operating frequency of the CPU is further increased and the operating voltage is further decreased, the current fluctuation becomes faster and larger, and the equivalent series inductance (ESL: Equivalent Series Inductance) possessed by the multilayer capacitor itself. ) Greatly affects the voltage fluctuation of the power supply. As a result, the ESL inhibits charging / discharging of the multilayer capacitor as the current fluctuates, so that the voltage fluctuation of the power supply tends to increase, and it has become difficult to adapt to future CPU speedup.

On the other hand, for example, as shown in Patent Document 1, Patent Document 2, or Patent Document 3, the internal electrodes and the side terminals are arranged so that the currents flowing in the adjacent terminal electrodes are opposite to each other. A multilayer capacitor has been proposed in which the mutual inductance is made negative, the parasitic inductor component of the capacitor is reduced, and low ESL is realized.

JP 2001-284170 A JP 2001-284171 A JP 2003-168621 A

The techniques described in Patent Document 1, Patent Document 2 and Patent Document 3 reduce the parasitic inductance of the capacitor element alone, but actually, the inductance of the wiring of the mounting board in addition to the capacitor also suppresses the voltage fluctuation of the power supply. It becomes a factor to inhibit. In consideration of the above-described facts, an object of the present invention is to provide an electronic circuit board that can reduce an equivalent series inductance that is a parasitic inductance of a capacitor or an inductance of wiring of a mounting board.

The electronic circuit board of the present invention includes a mounting board having a DC power supply layer and a ground layer, and a capacitor, and the capacitor is connected to the DC power supply layer and the ground layer via wiring and mounted on the mounting board. A first inductor that is a parasitic inductor component of the capacitor and a second inductor that is an inductor component of the wiring are connected in series, and at least one of the first inductor and the second inductor is magnetically connected. It has a closed conductor loop to be coupled.

According to the electronic circuit board having the above characteristics, at least one of the first inductor and the second inductor is magnetically coupled to the closed conductor loop, so that the first inductor and the second inductor can be coupled according to Faraday's law. A counter electromotive force is generated in the closed conductor loop so as to prevent the time fluctuation of the magnetic flux corresponding to at least one of the inductances. Thereby, the equivalent series inductance which is the parasitic inductance of a capacitor | condenser or the inductance of the wiring of a mounting board | substrate can be reduced.

Furthermore, in the electronic circuit board of the present invention, it is preferable that the closed conductor loop is configured by a wiring pattern formed inside the mounting board or on the surface of the mounting board.

According to the electronic circuit board having the above characteristics, the closed conductor loop is configured by the wiring pattern in the mounting board, thereby mainly preventing the time fluctuation of the magnetic flux corresponding to the inductance of the second inductor which is the inductor component of the wiring. The inductance (equivalent series inductance) of the wiring of the mounting board can be mainly reduced.

Furthermore, in the electronic circuit board of the present invention, it is preferable that a part of the closed conductor loop is one of the DC power supply layer and the ground layer.

According to the electronic circuit board having the above characteristics, unnecessary wiring can be reduced by using either the DC power supply layer or the ground layer as a part of the closed conductor loop.

In the electronic circuit board of the present invention, it is preferable that a component having a conductor pattern is mounted on the mounting board, and at least a part of the closed conductor loop is the conductor pattern.

According to the electronic circuit board having the above characteristics, at least a part of the closed conductor loop is a conductor pattern of a component mounted on the mounting board, so that the inductance of the first inductor that is a parasitic inductor component of the capacitor is mainly used. Can be prevented, and the parasitic inductance (equivalent series inductance) of the capacitor can be mainly reduced.

Furthermore, in the electronic circuit board of the present invention, it is preferable that the capacitor and the component are integrally formed.

According to the electronic circuit board having the above characteristics, the capacitor and the part having the conductor pattern that is at least a part of the closed conductor loop are integrally formed, whereby the first inductor that is the parasitic inductor component of the capacitor is It can be coupled to the closed conductor loop with a magnetically large coupling coefficient. Thereby, the parasitic inductance (equivalent series inductance) of the capacitor can be greatly reduced.

Furthermore, the electronic circuit board of the present invention preferably has a plurality of the closed conductor loops.

According to the electronic circuit board having the above characteristics, by having a plurality of closed conductor loops, a larger effect of reducing the equivalent series inductance can be obtained.

ADVANTAGE OF THE INVENTION According to this invention, the electronic circuit board which can reduce the equivalent series inductance of the wiring of a capacitor | condenser or a mounting board can be provided.

1 is a perspective view of an electronic circuit board according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line AA in FIG. 9 is a cross-sectional view taken along line BB in FIG. 1 or a cross-sectional view taken along line DD in FIG. It is explanatory drawing of the eddy current which generate | occur | produces with respect to the fluctuation | variation of magnetic flux by Faraday's law. It is a figure which shows the example of an equivalent circuit of the electronic circuit board which concerns on the 1st Embodiment of this invention. It is a graph which shows the calculation result by the circuit simulator of the equivalent circuit example shown in FIG. It is sectional drawing of the electronic circuit board which concerns on the modification of the 1st Embodiment of this invention. It is a perspective view of the electronic circuit board which concerns on the 2nd Embodiment of this invention. It is sectional drawing cut | disconnected by CC line in FIG. It is a figure which shows the equivalent circuit example of the electronic circuit board which concerns on the 2nd Embodiment of this invention. It is a perspective view of the electronic circuit board which concerns on the 3rd Embodiment of this invention. It is a disassembled perspective view which shows each internal electrode laminated | stacked within the components of the electronic circuit board which concerns on the 3rd Embodiment of this invention. FIG. 12 is a cross-sectional view of the part cut along line EE in FIG. 11. FIG. 12 is a cross-sectional view of a part cut along line FF in FIG. 11.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following description exemplifies a part of the embodiments of the present invention, and the present invention is not limited to these embodiments, so long as the form has the technical idea of the present invention. It is included in the scope of the present invention. Each configuration in each embodiment, a combination thereof, and the like are examples, and the addition, omission, replacement, and other changes of the configuration can be made without departing from the spirit of the present invention.

<First Embodiment>
FIG. 1 is a perspective view showing a configuration example of an electronic circuit board 1 according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. FIG. 3 is a sectional view taken along line BB in FIG. As shown in FIGS. 1 to 3, the electronic circuit board 1 includes a mounting substrate 111 having a ground layer 101 and a DC power supply layer 102 and a capacitor 104, and the capacitor 104 includes the ground layer 101 and the DC power supply layer 102. Are mounted on the surface of the mounting substrate 111 by being connected via the

wirings

103 a and 103 b of the mounting substrate 111.

The capacitor 104 has a plurality of first internal electrodes 1041 and a plurality of second internal electrodes 1042, and each first internal electrode 1041 and each second internal electrode 1042 are stacked via a dielectric 1043. ing. The capacitor 104 includes a first terminal electrode 1044 and a second terminal electrode 1045. The plurality of first internal electrodes 1041 are connected to the first terminal electrode 1044, and the plurality of second internal electrodes 1042 are The second terminal electrode 1045 is connected. The first terminal electrode 1044 is connected to the ground layer 101 through the wiring 103a, and the second terminal electrode 1045 is connected to the DC power supply layer 102 through the wiring 103b. As a result, as shown in the equivalent circuit diagram of FIG. 5, between the DC power supply layer 102 and the ground layer 101, the capacitor 104 (capacitance component thereof) and the first inductor 301 that is a parasitic inductor component of the capacitor 104 and the wiring 103a. , 103b, the second inductor 302, which is the inductor component, is connected in series. In FIG. 3, only one each of the first internal electrode 1041 and the second internal electrode 1042 is drawn for short.

As shown in FIGS. 1 and 2, the electronic circuit board 1 has a wiring pattern 105 formed on the surface of the mounting board 111. The electronic circuit board 1 has a closed conductor loop 110 formed by connecting both ends of the wiring pattern 105 to the DC power supply layer 102 via

wirings

103 c and 103 d formed inside the mounting substrate 111. . As shown in FIG. 5, the equivalent circuit of the closed conductor loop 110 is represented by connecting an inductor 303, which is an inductor component of the closed conductor loop 110, and a resistor 304, which is a resistance component, in series in a loop shape.

In this embodiment, since the closed conductor loop 110 is mainly formed in the mounting substrate 111, the inductor 303 of the closed conductor loop 110 is mainly composed of the second inductor 302 that is an inductor component of the wirings 103a and 103b. , Coupled through the generated magnetic field. Due to this coupling, a counter electromotive force is generated in the closed conductor loop 110 so as to prevent the time fluctuation of the magnetic flux generated by the noise current passing through the

wirings

103a and 103b according to Faraday's law (the closed circuit loop 110 is generated by this counter electromotive force). The magnetic flux generated by the eddy current generated in the circuit is generated so as to prevent the time fluctuation of the magnetic flux generated by the noise current passing through the

wirings

103a and 103b). As a result, the inductance (equivalent series inductance) of the second inductor 302 that is the inductor component of the wirings 103a and 103b can be mainly reduced.

This principle will be described in detail below. The inductance L is defined by the following formula (1) using the current I, the magnetic flux density B, the area S, and the time t. Considering this definition, the inductance is proportional to the time variation of the magnetic flux B · dS. Therefore, the inductance can be reduced by suppressing the time variation of the generated magnetic flux.

FIG. 4 shows a loop conductor 201 which is a closed conductor. When the magnetic flux 202 penetrating the inside of the loop of the loop conductor 201 is generated, an electromotive force is generated in a direction that cancels the generated magnetic flux 202 according to Faraday's law, an eddy current 204 flows in the loop conductor 201, and is opposite to the magnetic flux 202. Directional magnetic flux 203 is generated, and temporal fluctuation of the magnetic flux is suppressed.

In FIG. 3, when noise is generated in the DC power supply layer 102, a noise current 108 flows through the capacitor 104 through the

wirings

103 a and 103 b to the ground layer 101. At that time, a magnetic flux in a direction perpendicular to the cross section (paper surface in FIG. 3) is generated.

As shown in FIG. 2, a closed conductor loop 110 is formed by connecting both ends of the wiring pattern 105 to the DC power supply layer 102 via

wirings

103c and 103d. According to Faraday's law, an electromotive force is generated in a direction that prevents an increase in magnetic flux generated by the flow of the noise current 108, and an eddy current 107 opposite to the noise current 108 flows through the closed conductor loop 110. This prevents the time fluctuation of the magnetic flux generated by. Since the magnetic flux generated by the eddy current 107 cancels out the magnetic flux inside the mounting substrate 111 generated by the noise current 108, the equivalent series inductance of the second inductor 302 that is the inductor component of the wirings 103a and 103b of the mounting substrate 111 is reduced. be able to.

As described above, the electronic circuit board 1 includes the mounting substrate 111 having the DC power supply layer 102 and the ground layer 101, and the capacitor 104. The first inductor 301, which is the parasitic inductor component of the capacitor 104, and the second inductor 302, which is the inductor component of the wirings 103a and 103b, are connected in series, and are mounted on the mounting substrate 111. Since the closed conductor loop 110 magnetically coupled to the inductor 302 is provided, the magnetic flux coupling corresponding to the inductance of the second inductor 302 is obtained by Faraday's law by magnetically coupling the second inductor 302 and the closed conductor loop 110. Back electromotive force is generated in closed conductor loop 110 to prevent time fluctuation That. Thereby, the equivalent series inductance which is the inductance of the wirings 103a and 103b of the mounting substrate 111 can be reduced.

Further, in the electronic circuit board 1, the closed conductor loop 110 is configured by wiring patterns (

wirings

103 c and 103 d, the wiring pattern 105 and the DC power supply layer 102) formed inside the mounting board 111 or on the surface of the mounting board 111. Therefore, the time variation of the magnetic flux corresponding to the inductance of the second inductor 302 which is the inductor component of the wirings 103a and 103b is prevented, and the inductance (equivalent series inductance) of the wirings 103a and 103b of the mounting substrate 111 is mainly used. Can be reduced.

In the electronic circuit board 1, a part of the closed conductor loop 110 is the DC power supply layer 102, and therefore, unnecessary wiring can be reduced by using the DC electrode layer 102 as a part of the closed conductor loop 110.

FIG. 5 shows an equivalent circuit example of the electronic circuit board 1 when the closed conductor loop 110 and the second inductor 302 by the

wirings

103a and 103b are magnetically coupled. This equivalent circuit example is equivalent to a capacitor 104 connected in series between the DC power supply layer 102 and the ground layer 101, a first inductor 301 that is a parasitic inductor of the capacitor 104, and wirings 103 a and 103 b of the mounting substrate 111. This is a resistance component of a closed conductor loop 110 formed by a circuit in which a second inductor 302 that is a series inductor component is connected in series, the wiring pattern 105, the

wirings

103c and 103d of the mounting substrate 111, and the DC power supply layer 102. A circuit in which a resistor 304 and an inductor 303 that is an inductor component of the closed conductor loop 110 are connected in series, and the second inductor 302 and the inductor 303 of the closed conductor loop 110 are coupled with a coupling coefficient k. is there. In this equivalent circuit example, the capacitance of the capacitor 104 is 1 μF, the inductance of the first inductor 301 is 100 pH, the inductance of the second inductor 302 is 100 pH, the inductance of the inductor 303 of the closed conductor loop 110 is 1 pH, and the resistance value of the resistor 304 FIG. 6 shows the result of calculation by the circuit simulator of the impedance between the DC power supply layer 102 and the ground layer 101 of the equivalent circuit when the current is 0.1 μΩ. 6 that the inductance of the equivalent series inductor component between the DC power supply layer 102 and the ground layer 101 decreases as the coupling coefficient k increases to 0, 0.8, and 1. The case where k = 0 is equivalent to the case where the closed conductor loop 110 is not present, and the presence of the closed conductor loop 110 may reduce the inductance of the equivalent series inductor component between the DC power supply layer 102 and the ground layer 101. Recognize.

In the first embodiment, the wiring pattern 105 formed on the surface of the mounting substrate 111 constitutes a part of the closed conductor loop 110, but the wiring pattern 105 may be formed inside the mounting substrate 111. good. In the first embodiment, both ends of the wiring pattern 105 are connected to the DC power supply layer 102 via the

wirings

103c and 103d to form the closed conductor loop 110. The both ends of 105 may be formed by being connected to the ground layer 101 via wiring formed inside the mounting substrate 111. Even in this case, the same effect as the electronic circuit board 1 of the first embodiment can be obtained. Further, as in the electronic circuit board 2 shown in FIG. 7, the closed conductor loop 110 is configured such that both ends of the wiring pattern 105 are connected to the ground layer 101 and the DC power source via the

wirings

103 e and 103 f formed inside the mounting substrate 111. It may be formed by being connected to an independent wiring pattern 109 that is not connected to the layer 102. FIG. 7 is a cross-sectional view of the electronic circuit board 2 corresponding to the cross-sectional view of the electronic circuit board 1 shown in FIG. As long as the closed conductor loop is formed, the eddy current 107 generated by Faraday's law can reduce the equivalent series inductance that is the inductance of the wiring of the mounting board.

In the first embodiment, the electronic circuit board 1 having one closed conductor loop 110 is described. However, even if there are a plurality of closed conductor loops coupled to the second inductor 302 through a generated magnetic field. Good. For example, two closed conductor loops may be formed so as to sandwich a place where the capacitor 104 is mounted.
<Second Embodiment>

FIG. 8 is a perspective view showing an overall configuration example of the electronic circuit board 3 according to the second embodiment of the present invention. The electronic circuit board 3 will be described mainly with respect to differences from the electronic device 1 of the first embodiment, and description of common matters will be omitted as appropriate. Elements common to the electronic device 1 of the first embodiment are denoted by the same reference numerals, and description of the common elements is omitted. As in the first embodiment, the electronic circuit board 3 is mounted on the surface of the mounting board 111 with the capacitor 104 connected to the ground layer 101 and the power supply layer 102 via the

wirings

103 a and 103 b of the mounting board 111. ing. Further, in the electronic circuit board 3, a component 112 having a conductor pattern 305 is mounted on the surface of the mounting board 111. In the electronic circuit board 3, two components 112 are mounted on the surface of the mounting board 111 with the capacitor 104 interposed therebetween.

FIG. 9 is a cross-sectional view taken along the line CC of FIG. The component 112 has a conductor pattern 305 as shown in FIGS. A dielectric 3043 is formed around the conductor pattern 305. As shown in FIGS. 8 and 9, the electronic circuit board 3 has a closed conductor loop 310 formed by connecting both ends of the conductor pattern 305 to the DC power supply layer 102 via the

wirings

103 g and 103 h of the mounting board 111. Have two. As shown in FIG. 10, the equivalent circuit of the closed conductor loop 310 is represented by connecting an inductor 313 that is an inductor component of the closed conductor loop 310 and a resistor 304 that is a resistance component in series in a loop shape. The closed conductor loop 310 is generated with the first inductor 301 that is a parasitic inductor of the capacitor 104 and the second inductor 302 that is an equivalent series inductor of the

wirings

103 a and 103 b of the mounting substrate 111 connected to the capacitor 104. Coupling through a magnetic field.

A cross-sectional view taken along the line DD in FIG. 8 can be represented in FIG. 3 as in the first embodiment. As in the first embodiment, when noise is generated in the DC power supply layer 102, the noise current 108 flows through the capacitor 104 through the

wirings

103a and 103b and flows into the ground layer 101. ) Generates a magnetic flux in a direction perpendicular to. According to Faraday's law, an electromotive force is generated in a direction that prevents an increase in magnetic flux generated by the flow of the noise current 108, and an eddy current 107 opposite to the noise current 108 flows in the closed conductor loop 310. This prevents time fluctuations of the generated magnetic flux. The magnetic flux generated by the eddy current 107 cancels the magnetic flux generated by the noise current 108 inside the capacitor 104 and inside the mounting substrate 111, so that the first inductor 301, which is a parasitic inductor of the capacitor 104, and the wiring of the mounting substrate 111. Both of the equivalent series inductances of the second inductor 302, which are the

inductor components

103a and 103b, can be reduced.

FIG. 10 shows an equivalent circuit example for the electronic circuit board 3. This equivalent circuit example is equivalent to a capacitor 104 connected in series between the DC power supply layer 102 and the ground layer 101, a first inductor 301 that is a parasitic inductor of the capacitor 104, and wirings 103 a and 103 b of the mounting substrate 111. This is a resistance component of a closed conductor loop 310 formed by a circuit in which a second inductor 302 that is a series inductor component is connected in series, a conductor pattern 305,

wirings

103g and 103h of a mounting substrate 111, and a DC power supply layer 102. A resistor 304 and an inductor 303, which is an inductor component of the closed conductor loop 310, are connected in series, and the inductor 313 of the closed conductor loop 310 includes both the first inductor 301 and the second inductor 302. It is something that is combined with. Since the inductor 313 that is the inductor component of the closed conductor loop 310 is coupled to both the first inductor 301 and the second inductor 302, the first inductor 301 that is the parasitic inductor component of the capacitor 104 and the wiring 103a. , 103b, both inductances of the second inductor 302, which is the inductor component, can be reduced.

In addition, since the electronic circuit board 3 is formed with a plurality of closed conductor loops 310, it is possible to obtain a greater effect of reducing the equivalent series inductance. As can be seen from the simulation results shown in the first embodiment, the larger the coupling coefficient between the closed conductor loop 310 and the first inductor 301 or the second inductor 302 (closer to 1), the more the equivalent series inductance becomes. Although the effect of reducing becomes large, in reality, it is difficult to set the coupling coefficient to 1. By having the plurality of closed conductor loops 310, even if the coupling coefficient between each closed conductor loop 310 and the first inductor 301 or the second inductor 301 is smaller than 1, it is generated in each closed conductor loop 310. By adding the effects of the back electromotive force, it is possible to obtain a greater reduction effect of the equivalent series inductance.

The closed conductor loop 310 may be formed by connecting both ends of the conductor pattern 305 to the ground layer 101 via wiring formed inside the mounting substrate 111. In addition, the closed conductor loop 310 is connected at both ends of the conductor pattern 305 to independent wiring patterns that are not connected to the ground layer 101 or the DC power supply layer 102 via wiring formed inside the mounting substrate 111. It may be formed by this.

Further, the closed conductor loop 310 is formed by connecting both ends of the wiring pattern 305 to independent wiring patterns that are not connected to the ground layer 101 or the DC power supply layer 102, and the independent wiring patterns are formed on the mounting substrate. It may be formed on the surface of 111 or inside the component 112. In this case, the parasitic inductance (equivalent series inductance) of the capacitor 104 can be mainly reduced.

<Third Embodiment>
FIG. 11 is a perspective view showing a configuration example of an electronic circuit board 4 according to the third embodiment of the present invention. The electronic circuit board 4 will be described mainly with respect to differences from the electronic circuit board 3 of the second embodiment, and description of common matters will be omitted as appropriate. Elements common to the electronic circuit board 3 of the second embodiment are denoted by the same reference numerals, and description of the common elements is omitted. In the electronic circuit board 4, the component having the conductor pattern 305 and the capacitor 104 are integrally formed in place of the capacitor 104 and the two components 112 having the conductor pattern 305 in the electronic circuit substrate 3 of the second embodiment. The component 411 is mounted on the surface of the mounting substrate 111. In the electronic circuit board 4 shown in FIG. 11, the component 411 shows an example having one conductor pattern 305.

12 is an exploded perspective view of the part 411, FIG. 13 is a sectional view of the part 411 cut along the line EE in FIG. 11, and FIG. 14 is a part cut along the line FF in FIG. FIG. As shown in FIGS. 12 to 14, the first internal electrodes 1041 and the second internal electrodes 1042 are alternately stacked with the dielectric 1043 interposed therebetween, and the conductor pattern 305 is connected to the first internal electrodes via the dielectric 1043. 1041 and the second internal electrode 1042 are arranged apart from each other. The conductor pattern 305 is arranged so that at least a part of the conductor pattern 305 overlaps with the first internal electrode 1041 and the second internal electrode 1042 when viewed from the stacking direction of the first internal electrode 1041 and the second internal electrode 1042. Yes. The other points are the same as those of the electronic circuit board 3 of the second embodiment.

In the electronic circuit board 4, the component 411 in which the capacitor 104 and the component having the conductor pattern 305 that is a part of the closed conductor loop 310 are integrally formed is formed on the mounting substrate 111, so that the parasitic inductor of the capacitor 104 is formed. The first inductor 301 as a component can be coupled to the closed conductor loop 310 with a magnetically large coupling coefficient. Thereby, the parasitic inductance (equivalent series inductance) of the capacitor 104 can be greatly reduced.

The electronic circuit boards of the first to third embodiments described above may be used as a power supply module board such as a DC-DC converter, or a board used in a set of a smartphone, a PC, a notebook PC, or the like. It may be used as a board such as a graphic board, a microcomputer board, a memory board, and a PCI Express board.

DESCRIPTION OF SYMBOLS 101 Ground layer 102

Power supply layer

103a, 103b, 103c, 103d, 103e, 103f, 103g, 103h Wiring 104 Capacitor 105 Wiring pattern 107 Eddy current 108 Noise current 109 Wiring pattern 110 Closed conductor loop 111 Mounting substrate 112 Component 201 Closed conductor loop 202 Magnetic flux 203 Magnetic flux 204 Eddy current 301 First inductor 302 Second inductor 303 Inductor 304 Resistance 305 Conductor pattern 310 Closed conductor loop 313 Inductor 411 Component 1041 First internal electrode 1042 Second internal electrode 1043 Dielectric 1044 First Terminal electrode 1045 Second terminal electrode 3043 Dielectric

Claims

A mounting board having a DC power supply layer and a ground layer and a capacitor;
The capacitor is mounted on the mounting substrate by being connected to the DC power supply layer and the ground layer via wiring,
A first inductor that is a parasitic inductor component of the capacitor and a second inductor that is an inductor component of the wiring are connected in series,
An electronic circuit board comprising a closed conductor loop magnetically coupled to at least one of the first inductor and the second inductor.
2. The electronic circuit board according to claim 1, wherein the closed conductor loop is configured by a wiring pattern formed inside the mounting board or on a surface of the mounting board.
3. The electronic circuit board according to claim 1, wherein a part of the closed conductor loop is one of the DC power supply layer and the ground layer.
4. The electronic circuit board according to claim 1, wherein a component having a conductor pattern is mounted on the mounting board, and at least a part of the closed conductor loop is the conductor pattern.
5. The electronic circuit board according to claim 4, wherein the capacitor and the component are integrally formed.
6. The electronic circuit board according to claim 1, comprising a plurality of the closed conductor loops.