JP2018073956A - Printed circuit board for relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printed circuit board for relay in which in mounting of an IC having a frequency of 1GHz or more, measures for a power supply noise can be easily taken on a mother board even when the power supply noise is large.SOLUTION: As a capacitor 12 is built in or mounted on a substrate 1 while passing through a path from a power supply terminal of a semiconductor and a path of a mother board 3 to the ground, the present printed circuit board for relay 1 can reduce the distance from a power supply terminal of an IC to the capacitor 12, and thereby reducing an inductance to be generated. Thus measures for a power supply noise can be taken to a high frequency.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a printed wiring board for relay.

  In the design of a semiconductor (IC) package substrate, at the design stage, a capacitor can be arranged on the package substrate to take measures against power supply noise and to examine it. However, if it is found that the power supply noise of the IC is larger than expected after the design is completed, it is necessary to take measures against the power supply noise on the motherboard (for example, Patent Document 1). Inductance increases when measures against power supply noise are taken on the motherboard. Therefore, it is difficult to take measures against high-frequency (for example, 1 GHz or more) power supply noise on the motherboard.

JP 2005-150490 A

  The relay printed wiring board according to the present disclosure includes a substrate and a capacitor built in or mounted on the substrate, and the capacitor is provided on the substrate so that the capacitor passes through a path from the power supply terminal of the semiconductor and a path to the ground of the motherboard. Built-in or implemented.

FIG. 1 is an explanatory diagram illustrating a usage state of a printed wiring board for relay according to an embodiment of the present disclosure. FIG. 2 is an enlarged explanatory diagram illustrating a main part inside the printed wiring board for relay according to an embodiment of the present disclosure. FIG. 3 is an enlarged explanatory view showing a main part inside a printed wiring board for relay according to another embodiment of the present disclosure. FIG. 4A is an explanatory diagram illustrating an embodiment of an EBG structure provided on a printed wiring board for relay according to another embodiment of the present disclosure, and FIG. 4B is a power supply included in the EBG structure. It is explanatory drawing which shows a layer pattern, FIG.4 (C) is explanatory drawing which shows the capacitive coupling element contained in an EBG structure. FIG. 5 is a graph showing electromagnetic field simulation results for obtaining the resonance frequency of the resonance circuit of the EBG unit cell shown in FIG.

  The inductance is generated according to the distance from the power supply terminal of the IC to the capacitor that takes measures against power supply noise on the motherboard. If the generated inductance can be reduced, measures can be taken up to high frequencies. However, when the distance from the power supply terminal of the IC to the mother board is long, the inductance increases.

  The relay printed wiring board according to the present disclosure is built in or mounted on the substrate so that the capacitor passes through the path from the power supply terminal of the semiconductor and the path to the ground of the motherboard. As a result, the distance from the power supply terminal of the IC to the capacitor can be shortened, and the generated inductance can be reduced. Therefore, it is possible to effectively take measures against power supply noise up to high frequencies. Hereinafter, the relay printed wiring board of the present disclosure will be described in detail.

  As shown in FIG. 1, the relay printed wiring board 1 according to an embodiment of the present disclosure is used to electrically connect an IC package 2 and a mother board 3 using solder balls 4. The relay printed wiring board 1 includes a substrate 11 and a capacitor 12.

  The substrate 11 is not particularly limited as long as it is made of an insulating material. Examples of the insulating material include organic resins such as epoxy resins, bismaleimide-triazine resins, polyimide resins, and polyphenylene ether resins. These organic resins may be used in combination of two or more. When an organic resin is used as a material having insulating properties, a reinforcing material may be added to the organic resin. Examples of the reinforcing material include insulating fabric materials such as glass fiber, glass nonwoven fabric, aramid nonwoven fabric, aramid fiber, and polyester fiber. Two or more reinforcing materials may be used in combination. Further, the insulating material may include inorganic fillers such as silica, barium sulfate, talc, clay, glass, calcium carbonate, and titanium oxide.

  As shown in FIG. 2, a power supply plane 13 and a ground 14 are formed on the substrate 11. The power plane 13 and the ground 14 are formed of a conductor, and examples of the conductor include copper, aluminum, gold, and silver. Copper is desirable from the viewpoint of workability and cost.

  At least a part of the power supply plane 13 and the ground 14 formed on the surface of the substrate 11 acts as a terminal 15. The terminal 15 includes a terminal on the IC package side and a terminal on the motherboard side. As shown in FIG. 2, the terminals 15 may be arranged on both surfaces of the substrate 11 at the same pitch, and may be formed symmetrically with respect to the substrate 11.

  The capacitor 12 is built in the substrate 11 through the terminal 15 on the IC package side and the terminal 15 on the motherboard side. By incorporating the capacitor 12 in this way, the path from the power supply terminal of the IC 22 and the path to the ground of the motherboard 3 are electrically connected via the capacitor 12. The position where the capacitor 12 is built is not particularly limited. For example, it is better that the capacitor 12 is built on the IC package side from the center in the thickness direction of the substrate 11.

  A via 16 is formed in order to electrically connect between the power planes 13 and the ground 14 or between these and the capacitor 12. The via 16 is not particularly limited, and is formed of a conductor, for example. Examples of the conductor include copper, aluminum, gold, and silver. Copper is preferable from the viewpoint of workability and cost. The via 16 may be attached to the inner wall surface of the via forming hole, or may be in the form of a filled via that fills the via forming hole.

  Next, a method for using the relay printed wiring board 1 according to an embodiment of the present disclosure will be described. As shown in FIG. 1, the relay printed wiring board 1 is connected to the surface of the mother board 3 via solder balls 4. Further, the IC package 2 is connected to the surface of the relay printed wiring board 1 via the solder balls 4. In this manner, the IC package 2 and the mother board 3 are connected via the relay printed wiring board 1. The IC package 2 and the mother board 3 are not particularly limited, and examples thereof include general IC packages and mother boards that have been conventionally used.

  By using the relay printed wiring board 1 in this way, the distance from the power supply terminal of the IC 22 included in the IC package 2 to the capacitor 12 included in the relay printed wiring board 1 can be shortened. As a result, the inductance can be reduced, and countermeasures and examinations can be performed for high frequency power supply noise of the IC 22 included in the IC package 2. For example, countermeasures and investigations can be made even with high-frequency power supply noise exceeding 1 GHz.

  Next, a printed wiring board for relay according to another embodiment of the present disclosure will be described. As shown in FIG. 3, the relay printed wiring board 1 ′ according to another embodiment includes an EBG structure 5 including at least one EBG unit cell. “EBG” refers to an electromagnetic band gap. The position where the EBG structure 5 is provided is provided on the mother board 3 side of the power supply plane 13 connected to the terminal 15 on the IC package side from the portion connected to the capacitor 12. The relay printed wiring board 1 ′ has substantially the same structure as the relay printed wiring board 1 except that it includes the EBG structure 5. Therefore, members other than the EBG structure 5 are denoted by the same reference numerals as those of the printed wiring board 1 for relay, and detailed description thereof is omitted. Further, in FIG. 3, a part of the solder ball 4 and a part of the terminal 15 which are not directly related to the main part are omitted.

  The EBG structure 5 included in the relay printed wiring board 1 ′ is not particularly limited. An embodiment of the EBG structure 5 will be described with reference to FIGS.

  FIG. 4A shows a part of the EBG structure 5 provided on the printed wiring board 1 ′ for relay. As shown in FIG. 4A, the EBG structure 5 is formed by a plurality of EBG unit cells 51. FIG. 4A shows three extracted EBG unit cells 51 arranged side by side in the direction along the branch 522.

  As shown in FIGS. 4B and 4C, the EBG unit cell 51 shown in FIG. 4A has the power supply layer wiring 523 of the power supply layer pattern 52 and the capacitive coupling element wiring 532 of the capacitive coupling element 53 as shown in FIGS. The rectangular power supply layer electrode 521 and the substantially rectangular capacitive coupling element body 531 are surrounded by approximately one side and approximately half a circumference, respectively.

  Specifically, as shown in FIG. 4B, the power supply layer pattern 52 is distinguished into a power supply layer electrode 521, a branch 522, and a power supply layer wiring 523 by forming a slit in a part of the power supply layer. ing. The power supply layer electrode 521 has a substantially rectangular shape. The power supply layer wiring 523 has a length of approximately one side of the power supply layer electrode 521 from one corner 521a of the power supply layer electrode 521 to one adjacent corner 521b. The branch 522 is connected to one corner of the power supply layer electrode 521 at the tip thereof via the adjacent power supply layer wiring 523. Connection between the branch 522 and one corner of the power supply layer electrode 521 may be directly connected to a part of both without passing through the adjacent power supply layer wiring 523.

  As shown in FIG. 4C, the capacitive coupling element body 531 has a substantially rectangular shape and is approximately the same size as the power supply layer electrode 521. The capacitive coupling element wiring 532 is formed so as to surround the circumference of the capacitive coupling element main body 531 by more than half a circle so as to be substantially at the same position as one corner 521a of the branch 522.

  The power supply layer electrode 521 and the capacitive coupling element 53 are capacitively coupled via an insulating layer. On the other hand, a part of the power supply layer electrode 521 and the branch 522 are connected via an adjacent power supply layer wiring 523, and at the same time, a via 54 is formed at the tip of the capacitive coupling element wiring 532 extending from the capacitive coupling element 53. And connected to the branch 522. The via 54 is formed of a conductive material such as copper, for example.

  FIG. 5 is a graph showing electromagnetic field simulation results for obtaining the resonance frequency of the resonance circuit of the EBG unit cell 51. From this resonance analysis result, it can be seen that the EBG structure 5 can set a blocking region that suppresses electromagnetic noise propagation in a band near 2.4 GHz. Therefore, when the relay printed wiring board includes an EBG structure, even if the power supply noise is at a higher frequency, it is possible to suppress the noise from being propagated to the mother board, and to take countermeasures and studies.

  The relay printed wiring board of the present disclosure is not limited to the above-described embodiment. In the above-described embodiment, all the capacitors 12 are built in the substrate 11. However, the capacitor may be mounted on the substrate through a path from the power supply terminal of the semiconductor and a path to the ground of the motherboard. In this case, in order to further shorten the distance from the power supply terminal of the IC to the capacitor, the capacitor is preferably mounted on the IC package side of the substrate.

  In the above-described embodiment, the terminals 15 are arranged at the same pitch on both surfaces of the substrate 11 and are formed symmetrically with respect to the substrate 11. However, the arrangement of the terminals is not particularly limited, and may not be formed symmetrically with respect to the board. The upper side of the pitch of the solder balls 4 of the IC 22 is arranged so that the relay printed wiring board can also be used as a package board. The pitch may be narrower than the lower side.

1, 1 ′ Printed wiring board for relay 11 Substrate 12 Capacitor 13 Power plane 14 Ground 15 Terminal 16 Via 2 IC package 21 Package substrate 22 IC
3 Motherboard 4 Solder Ball 5 EBG Structure 51 EBG Unit Cell 52 Power Supply Layer Pattern 521 Power Supply Layer Electrode 521a, 521b Corner 522 Branch 523 Power Supply Layer Wiring 53 Capacitive Coupling Element 531 Capacitive Coupling Element Main Body 532 Capacitive Coupling Element Wiring 54 Via

Claims (9)

A substrate,
Including capacitors built in or mounted on the board,
A printed wiring board for relay that is built in or mounted on a substrate so that a capacitor passes through a path from a semiconductor power supply terminal and a path to the ground of a motherboard.   The printed wiring board for relay according to claim 1, wherein the substrate further includes a power plane and a ground.   The printed wiring board for relay according to claim 2, wherein the substrate further includes at least one EBG unit cell provided on the power plane.   The printed wiring board for relay according to claim 1, wherein the capacitor is built in the substrate.   The board further includes terminals formed on both surfaces at the same pitch and symmetrical with respect to the board, and the terminals formed symmetrical with respect to the board are electrically connected to each other. The printed wiring board for relay according to any one of claims 1 to 4. The EBG unit cell is
Including power and ground layers,
The power supply layer pattern formed in the power supply layer includes a branch that is a DC power supply path that connects adjacent EBG unit cells, and a power supply layer electrode,
A capacitive coupling element including a capacitive coupling element body is disposed with an interlayer so as to face the power supply layer electrode,
The power supply layer pattern further includes power supply layer wiring extending from the power supply layer electrode and surrounding at least a part of the periphery of the electrode, or the capacitive coupling element extends from the capacitive coupling element body. And further includes a capacitive coupling element wiring formed so as to surround at least a part of the periphery of the main body, or the power supply layer pattern further includes the power supply layer wiring and the capacitive coupling element is the capacitive coupling element wiring. Further including
The power supply layer pattern and the capacitive coupling element have an EBG structure in which EBG unit cells connected via at least one of the power supply layer wiring and the capacitive coupling element wiring are periodically arranged. The printed wiring board for relay according to any one of claims 3 to 5. The power supply layer electrode and the capacitive coupling element body are substantially rectangular and have substantially the same size,
The branch extends from one corner of the power layer electrode, which is distinguished by forming a slit, to the vicinity of one adjacent corner;
The capacitive coupling element wiring extends in a direction in which a branch extends from a corner of the capacitive coupling element body;
The printed wiring board for relay according to claim 6, wherein the branch and the capacitive coupling element wiring are connected to each other through a via at each tip portion. The power supply layer electrode and the capacitive coupling element body are substantially rectangular and have substantially the same size, and the power supply layer wiring has a length of at least substantially one side around the power supply layer electrode, and the capacitive coupling element The wiring sees at least half the circumference of the capacitive coupling element body,
The printed wiring board for relay according to claim 6, wherein the power supply layer wiring and the capacitive coupling element wiring are connected to each other at a leading end portion via a via.   The printed wiring board for relay according to any one of claims 6 to 8, wherein a thickness between layers of the power supply layer pattern and the capacitive coupling element is 25 µm or less.

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