Shielded flat cable with PCB

Abstract

To provide a shielded flat cable capable of suppressing an influence of external noise and crosstalk also in a high frequency region, and a shielded flat cable with a substrate.SOLUTION: A shielded flat cable includes: a first differential signal line pair including a first signal line and a second signal line parallel to each other; a first ground line parallel to the first differential signal line pair; a second ground line that is parallel to the first differential signal line pair and that has the first differential signal line pair arranged between the first ground line and itself; an insulation layer covering the first differential signal line pair, the first ground line, and the second ground line; a first shield layer covering a first surface of the insulation layer; and a second shield layer covering a surface opposite the first surface being a second surface of the insulation layer. A first opening exposing the first ground line is formed on the first surface side of the insulating layer, and the first shield layer is connected to the first ground line through the first opening. A width of the first ground line is greater than the width of the first signal line and the width of the second signal line.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] This disclosure , basis This relates to a plate-attached shielded flat cable. [Background technology]

[0002] A shielded flat cable intended to be less susceptible to the effects of external noise and crosstalk has been disclosed (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 208247 Summary of the Invention [Problem to be solved by the invention]

[0004] Although the shielded flat cable described in Patent Document 1 achieves the intended purpose, the frequency of transmitted signals has increased in recent years, and there is a risk of the cable being affected by external noise or of crosstalk occurring.

[0005] The present disclosure is capable of suppressing the influence of external noise and crosstalk even in the high frequency range. Base The object of the present invention is to provide a plate-attached shielded flat cable. [Means for solving the problem]

[0006] A shielded flat cable of the present disclosure includes a first differential signal line pair including a first signal line and a second signal line parallel to each other, a first ground wire parallel to the first differential signal line pair, a second ground wire parallel to the first differential signal line pair and disposing the first differential signal line pair between the first ground wire, an insulating layer covering the first differential signal line pair, the first ground wire, and the second ground wire, a first shield layer covering a first surface of the insulating layer, and a second shield layer on a surface opposite to the first surface and covering a second surface of the insulating layer, wherein a first opening exposing the first ground wire is formed on the first surface side of the insulating layer, the first shield layer is connected to the first ground wire via the first opening, and a width of the first ground wire is larger than a width of the first signal line and a width of the second signal line. Effect of the Invention

[0007] According to the present disclosure, the influence of external noise and crosstalk can be suppressed even in the high frequency range. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view showing a shielded flat cable according to a first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing the shielded flat cable according to the first embodiment. [Diagram 3] FIG. 3 is a cross-sectional view showing the dimensions of each part. [Figure 4] FIG. 4 is a plan view showing a substrate to which a shielded flat cable is connected. [Diagram 5] FIG. 5 is a cross-sectional view (part 1) showing a board to which a shielded flat cable is connected. [Figure 6] FIG. 6 is a cross-sectional view (part 2) showing a board to which a shielded flat cable is connected. [Figure 7] FIG. 7 is a cross-sectional view (part 3) showing a board to which a shielded flat cable is connected. [Figure 8]FIG. 8 is a cross-sectional view showing a shielded flat cable according to the second embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing a shielded flat cable according to a third embodiment. [Figure 10] FIG. 10 is a cross-sectional view showing a shielded flat cable according to a fourth embodiment. [Figure 11] FIG. 11 is a cross-sectional view showing a shielded flat cable according to a fifth embodiment. [Figure 12] FIG. 12 is a cross-sectional view showing a shielded flat cable according to a sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [Description of the embodiments of the present disclosure] First, the embodiments of the present disclosure will be listed and described.

[0010] [1] A shielded flat cable according to one aspect of the present disclosure includes: a first differential signal line pair including first and second signal lines parallel to each other; a first ground line parallel to the first differential signal line pair; a second ground line parallel to the first differential signal line pair and interposing the first differential signal line pair between the first ground line; an insulating layer covering the first differential signal line pair, the first ground line, and the second ground line; a first shield layer covering a first surface of the insulating layer; and a second shield layer covering a second surface of the insulating layer opposite to the first surface, wherein a first opening exposing the first ground line is formed on the first surface side of the insulating layer, the first shield layer is connected to the first ground line through the first opening, and a width of the first ground line is larger than a width of the first signal line and a width of the second signal line.

[0011] The width of the first ground line is greater than the width of the first signal line and the width of the second signal line, so that the ground potential of the first ground line is stable and the influence of external noise and crosstalk on the first differential signal line pair can be suppressed even in high frequency regions.

[0012] [2] In the configuration of [1], the first ground line may be entirely overlapped with the second shield layer via the insulating layer on the second surface side, thereby reducing the number of steps and costs required to form an opening.

[0013] [3] In the configuration of [1] or [2], a second opening exposing the second ground line may be formed on the second surface side of the insulating layer, the second shielding layer may be connected to the second ground line through the second opening, and the second ground line may be entirely overlapped with the first shielding layer via the insulating layer on the first surface side. In this case, it is easy to suppress the influence of external noise on the first differential signal line pair and crosstalk.

[0014] [4] In the method of [1], a third opening exposing the first ground line may be formed on the second surface side of the insulating layer, and the second shielding layer may be connected to the first ground line via the third opening. In this case, it is easy to suppress the influence of external noise and crosstalk on the first differential signal line pair.

[0015] [5] In the configuration of [1], a second opening exposing the second ground line may be formed on the second surface side of the insulating layer, the second shielding layer may be connected to the second ground line via the second opening, the second ground line may be entirely overlapped with the first shielding layer via the insulating layer on the first surface side, and a third opening exposing the first ground line may be formed on the second surface side of the insulating layer, and the second shielding layer may be connected to the first ground line via the third opening. In this case, it is easy to suppress the influence of external noise on the first differential signal line pair and crosstalk.

[0016] [6] In any of [1] to [5], in a cross-sectional view perpendicular to the longitudinal direction, the first shield layer and the second shield layer may protrude from at least one end side of the insulating layer and be joined to each other at the protruding portions, which makes it difficult for the first shield layer and the second shield layer to peel off from the insulating layer.

[0017] [7] In any of [1] to [6], the width of the first ground wire may be greater than the width of the first differential signal wire pair. In this case, it is easy to stabilize the ground potential of the first ground wire and to suppress the influence of external noise on the first differential signal wire pair and crosstalk. In addition, it is easy to bring the first shield layer into contact with the first ground wire when manufacturing the shielded flat cable.

[0018] [8] In any of [1] to [7], a distance between the first differential signal line pair and the first ground wire may be greater than a distance between the first signal wire and the second signal wire, which makes it easier to bring the first shield layer into contact with the first ground wire during manufacture of the shielded flat cable.

[0019] [9] In any of [1] to [8], a width of the first differential signal line pair may be greater than a distance between the first differential signal line pair and the first ground line, which makes it easier to suppress the influence of external noise on the first differential signal line pair and crosstalk.

[0020]

[10] In any of [1] to [9], the width of the first ground wire may be greater than the distance between the first differential signal line pair and the first ground wire. In this case, it is easy to stabilize the ground potential of the first ground wire and to suppress the influence of external noise and crosstalk. In addition, it is easy to bring the first shield layer into contact with the first ground wire when manufacturing the shielded flat cable.

[0021]

[11] In any one of [1] to

[10] , an intermediate portion may be provided between the first shield layer and the insulating layer, the intermediate portion being parallel to the first differential signal line pair and overlapping the first differential signal line pair in a plan view, and the width of the first ground line may be smaller than the width of the intermediate portion, making it easier to adjust the impedance of the first differential signal line pair.

[0022]

[12] In any one of [1] to

[11] , the semiconductor device may further include a second differential signal line pair including a third signal line and a fourth signal line parallel to the first differential signal line pair, the insulating layer may cover the second differential signal line pair, and the first ground line may be disposed between the first differential signal line pair and the second differential signal line pair. In this case, crosstalk between the first differential signal line pair and the second differential signal line pair can be suppressed even in a high frequency region.

[0023]

[13] A shielded flat cable according to another aspect of the present disclosure includes a first differential signal line pair including a first signal line and a second signal line parallel to each other, a second differential signal line pair including a third signal line and a fourth signal line parallel to the first differential signal line pair, a first ground line parallel to the first differential signal line pair, a second ground line parallel to the first differential signal line pair, an insulating layer covering the first differential signal line pair, the second differential signal line pair, the first ground line, and the second ground line, and a shield layer covering the insulating layer, wherein the first differential signal line pair, the second differential signal line pair, the first ground line, and the second ground line are aligned on a virtual plane, the first ground line is disposed between the first differential signal line pair and the second differential signal line pair, and the first differential signal line pair is disposed between the first ground line and the second ground line. a first opening reaching the first ground line and a second opening reaching the second ground line are formed in the insulating layer, the first opening is formed only on a first direction side of the first ground line perpendicular to the imaginary plane, and a face of the first ground line on a second direction side opposite to the first direction side is entirely covered with the insulating layer, the second opening is formed only on the second direction side of the second ground line, and a face of the second ground line on the first direction side is entirely covered with the insulating layer, the shielding layer is connected to the first ground line through the first opening and to the second ground line through the second opening, and a width of the first ground line and a width of the second ground line are larger than a width of the first signal line, a width of the second signal line, a width of the third signal line, and a width of the fourth signal line.

[0024] The width of the first ground line and the width of the second ground line are greater than the width of the first signal line, the width of the second signal line, the width of the third signal line, and the width of the fourth signal line, so that even in the high frequency range, the influence of external noise on the first differential signal line pair, the influence of external noise on the second differential signal line pair, and crosstalk between the first differential signal line pair and the second differential signal line pair can be suppressed.

[0025]

[14] A shielded flat cable with a substrate according to yet another embodiment of the present disclosure includes the shielded flat cable according to any one of [1] to

[12] , and a substrate to which an end portion of the shielded flat cable is connected, the substrate includes a first ground pattern to which the first ground wire is electrically connected, a second ground pattern to which the second ground wire is electrically connected, and a first signal pattern and a second signal pattern to which the first differential signal line pair is electrically connected, the substrate includes a resin covering the first ground wire, the second ground wire, and the first differential signal line pair that are exposed from the insulating layer at the end portion, the resin having a relative dielectric constant of 2.0 or more and 2.6 or less. In this case, impedance disturbance can be suppressed.

[0026]

[15] In

[14] , the first differential signal line pair exposed from the insulating layer may be connected in a straight line to the first signal pattern and the second signal pattern. In this case, it is possible to reduce the disturbance of the characteristic impedance at the connection part, and as a result, it is possible to reduce the reflection loss and the degradation of the signal.

[0027]

[16] In the configuration of

[14] or

[15] , the first ground line exposed from the insulating layer may be connected in a straight line to the first ground pattern. In this case, it is possible to reduce the disturbance of the characteristic impedance at the connection part, thereby reducing the reflection loss and the degradation of the signal.

[0028] [Details of the embodiment of the present disclosure] Hereinafter, the embodiments of the present disclosure will be described in detail, but the present disclosure is not limited thereto. In this specification and drawings, components having substantially the same functional configuration may be denoted by the same reference numerals to avoid redundant description. In this specification and drawings, the X1-X2 direction, the Y1-Y2 direction, and the Z1-Z2 direction are defined as mutually orthogonal directions. A plane including the X1-X2 direction and the Y1-Y2 direction is defined as the XY plane, a plane including the Y1-Y2 direction and the Z1-Z2 direction is defined as the YZ plane, and a plane including the Z1-Z2 direction and the X1-X2 direction is defined as the ZX plane. For convenience, the Z1 direction is defined as the upward direction, and the Z2 direction is defined as the downward direction. In this disclosure, planar view refers to viewing an object from the Z1 side.

[0029] (First embodiment) A first embodiment will be described. Fig. 1 is a plan view showing a shielded flat cable according to the first embodiment. Fig. 2 is a cross-sectional view showing the shielded flat cable according to the first embodiment. Fig. 2 corresponds to a cross-sectional view taken along line II-II in Fig. 1. Fig. 3 is a cross-sectional view showing the dimensions of each part.

[0030] 1 and 2, the shielded flat cable 1 according to the first embodiment includes a first differential signal line pair 11, a second differential signal line pair 12, a first ground line 210, a second ground line 220, and a third ground line 230. The first differential signal line pair 11, the second differential signal line pair 12, the first ground line 210, the second ground line 220, and the third ground line 230 extend in the Y1-Y2 direction and are aligned in the X1-X2 direction. The Y1-Y2 direction is the longitudinal direction of the shielded flat cable 1, and is the longitudinal direction of the first differential signal line pair 11, the second differential signal line pair 12, the first ground line 210, the second ground line 220, and the third ground line 230. For example, the first differential signal line pair 11, the second differential signal line pair 12, the first ground line 210, the second ground line 220, and the third ground line 230 are aligned on a virtual plane 10 parallel to the XY plane.

[0031] The second ground wire 220 is on the X2 side of the first ground wire 210, and the third ground wire 230 is on the X1 side of the first ground wire 210. Therefore, the first ground wire 210 is located between the second ground wire 220 and the third ground wire 230. The first ground wire 210, the second ground wire 220, and the third ground wire 230 are made of soft copper with a tin-plated layer formed on the surface.

[0032] The first ground line 210 is, for example, a rectangular conductor. The first ground line 210 has a first surface 211, a second surface 212, a third surface 213, and a fourth surface 214. The first surface 211 and the second surface 212 are parallel to the XY plane, and the third surface 213 and the fourth surface 214 are parallel to the YZ plane. The second surface 212 is on the Z2 side of the first surface 211, and the fourth surface 214 is on the X2 side of the third surface 213. The width WG1 of the first ground line 210 is, for example, 2.0 mm or more and 4.0 mm or less. The width WG1 is the distance between the third surface 213 and the fourth surface 214. The thickness TG1 of the first ground line 210 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TG1 is the distance between the first surface 211 and the second surface 212.

[0033] The second ground line 220 is, for example, a rectangular conductor. The second ground line 220 has a first surface 221, a second surface 222, a third surface 223, and a fourth surface 224. The first surface 221 and the second surface 222 are parallel to the XY plane, and the third surface 223 and the fourth surface 224 are parallel to the YZ plane. The second surface 222 is on the Z2 side of the first surface 221, and the fourth surface 224 is on the X2 side of the third surface 223. The width WG2 of the second ground line 220 is, for example, 2.0 mm or more and 4.0 mm or less. The width WG2 is the distance between the third surface 223 and the fourth surface 224. The thickness TG2 of the second ground line 220 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TG2 is the distance between the first surface 221 and the second surface 222.

[0034] The third ground line 230 is, for example, a rectangular conductor. The third ground line 230 has a first surface 231, a second surface 232, a third surface 233, and a fourth surface 234. The first surface 231 and the second surface 232 are parallel to the XY plane, and the third surface 233 and the fourth surface 234 are parallel to the YZ plane. The second surface 232 is on the Z2 side of the first surface 231, and the fourth surface 234 is on the X2 side of the third surface 233. The width WG3 of the third ground line 230 is, for example, 2.0 mm or more and 4.0 mm or less. The width WG3 is the distance between the third surface 233 and the fourth surface 234. The thickness TG3 of the third ground line 230 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TG3 is the distance between the first surface 231 and the second surface 232.

[0035] The first differential signal line pair 11 is between the first ground line 210 and the second ground line 220, and the second differential signal line pair 12 is between the first ground line 210 and the third ground line 230. The first differential signal line pair 11 has a first signal line 110 and a second signal line 120, and transmits a differential signal. The second signal line 120 is on the X1 side of the first signal line 110. The second differential signal line pair 12 has a third signal line 130 and a fourth signal line 140, and transmits a differential signal. The fourth signal line 140 is on the X1 side of the third signal line 130. The first signal line 110, the second signal line 120, the third signal line 130, and the fourth signal line 140 are made of plating-less soft copper on which no plating layer is formed. The first signal line 110, the second signal line 120, the third signal line 130 and the fourth signal line 140 may be made of soft copper having a tin-plated layer formed on the surface.

[0036] The first signal line 110 is, for example, a rectangular conductor. The first signal line 110 has a first surface 111, a second surface 112, a third surface 113, and a fourth surface 114. The first surface 111 and the second surface 112 are parallel to the XY plane, and the third surface 113 and the fourth surface 114 are parallel to the YZ plane. The second surface 112 is on the Z2 side of the first surface 111, and the fourth surface 114 is on the X2 side of the third surface 113. The width WS1 of the first signal line 110 is, for example, 0.10 mm or more and 0.50 mm or less. The width WS1 is the distance between the third surface 113 and the fourth surface 114. The thickness TS1 of the first signal line 110 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TS1 is the distance between the first surface 111 and the second surface 112. The first signal line 110 may be a round conductor.

[0037] The second signal line 120 is, for example, a rectangular conductor. The second signal line 120 has a first surface 121, a second surface 122, a third surface 123, and a fourth surface 124. The first surface 121 and the second surface 122 are parallel to the XY plane, and the third surface 123 and the fourth surface 124 are parallel to the YZ plane. The second surface 122 is on the Z2 side of the first surface 121, and the fourth surface 124 is on the X2 side of the third surface 123. The width WS2 of the second signal line 120 is, for example, 0.10 mm or more and 0.50 mm or less. The width WS2 is the distance between the third surface 123 and the fourth surface 124. The thickness TS2 of the second signal line 120 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TS2 is the distance between the first surface 121 and the second surface 122. The second signal line 120 may be a round conductor.

[0038] The distance LSS1 between the first signal line 110 and the second signal line 120 is, for example, 0.10 mm or more and 2.00 mm or less. The distance LSS1 is the distance between the third surface 113 of the first signal line 110 and the fourth surface 124 of the second signal line 120.

[0039] The third signal line 130 is, for example, a rectangular conductor. The third signal line 130 has a first surface 131, a second surface 132, a third surface 133, and a fourth surface 134. The first surface 131 and the second surface 132 are parallel to the XY plane, and the third surface 133 and the fourth surface 134 are parallel to the YZ plane. The second surface 132 is on the Z2 side of the first surface 131, and the fourth surface 134 is on the X2 side of the third surface 133. The width WS3 of the third signal line 130 is, for example, 0.10 mm or more and 0.50 mm or less. The width WS3 is the distance between the third surface 133 and the fourth surface 134. The thickness TS3 of the third signal line 130 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TS3 is the distance between the first surface 131 and the second surface 132. The third signal line 130 may be a round conductor.

[0040] The fourth signal line 140 is, for example, a rectangular conductor. The fourth signal line 140 has a first surface 141, a second surface 142, a third surface 143, and a fourth surface 144. The first surface 141 and the second surface 142 are parallel to the XY plane, and the third surface 143 and the fourth surface 144 are parallel to the YZ plane. The second surface 142 is on the Z2 side of the first surface 141, and the fourth surface 144 is on the X2 side of the third surface 143. The width WS4 of the fourth signal line 140 is, for example, 0.10 mm or more and 0.50 mm or less. The width WS4 is the distance between the third surface 143 and the fourth surface 144. The thickness TS4 of the fourth signal line 140 is, for example, 0.02 mm or more and 0.20 mm or less. The thickness TS4 is the distance between the first surface 141 and the second surface 142. The fourth signal line 140 may be a round conductor.

[0041] The distance LSS2 between the third signal line 130 and the fourth signal line 140 is, for example, 0.10 mm or more and 2.00 mm or less. The distance LSS2 is the distance between the third surface 133 of the third signal line 130 and the fourth surface 144 of the fourth signal line 140.

[0042] The width WG1 of the first ground line 210, the width WG2 of the second ground line 220, and the width WG3 of the third ground line 230 are larger than the width WS1 of the first signal line 110, the width WS2 of the second signal line 120, the width WS3 of the third signal line 130, and the width WS4 of the fourth signal line 140.

[0043] The shielded flat cable 1 has an insulating layer 20 that covers the first differential signal line pair 11, the second differential signal line pair 12, the first ground line 210, the second ground line 220, and the third ground line 230. The insulating layer 20 has a first insulating layer 21 and a second insulating layer 22 that sandwich an imaginary plane 10 therebetween. The first insulating layer 21 is on the Z1 side of the imaginary plane 10, and the second insulating layer 22 is on the Z2 side of the imaginary plane 10. The insulating layer 20 has a first surface facing the Z1 direction and a second surface facing the Z2 direction. The first surface is constituted by the first insulating layer 21, and the second surface is constituted by the second insulating layer 22.

[0044] The first insulating layer 21 has a base material 21B and an adhesive layer 21A from the outside, and the second insulating layer 22 has a base material 22B and an adhesive layer 22A from the outside (see Figs. 5 to 7). Examples of the material of the base materials 21B and 22B include polyester resin, polyphenylene sulfide resin, polyimide resin, etc. Examples of the polyester resin include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene naphthalate resin, etc. Among these resins, polyethylene terephthalate resin is preferable from the viewpoints of electrical properties, mechanical properties, cost, etc. Examples of the material of the adhesive layers 21A and 22A include polypropylene resin. The first insulating layer 21 and the second insulating layer 22 may have a single-layer structure. For example, the first insulating layer 21 and the second insulating layer 22 may be formed only of resin by extrusion molding.

[0045] The shielded flat cable 1 has a shield layer 30 provided on the outside of the insulating layer 20. The shield layer 30 covers the insulating layer 20. The shield layer 30 has a first shield layer 31 on the Z1 side of the first insulating layer 21 and a second shield layer 32 on the Z2 side of the second insulating layer 22. The first shield layer 31 has a metal foil 31B and a conductive adhesive layer 31A (see Figures 5 to 7). The metal foil 31B is, for example, copper foil or aluminum foil. The second shield layer 32 has a metal foil 32B and a conductive adhesive layer 32A (see Figures 5 to 7). The metal foil 32B is, for example, copper foil or aluminum foil. In the first shield layer 31, the conductive adhesive Layer 31A Metal foil31B and the first insulating layer 21. In the second shield layer 32, a conductive adhesive Layer 32A Metal foil 32B and the second insulating layer 22. The first shield layer 31 and the second shield layer 32 have a thickness of, for example, 0.02 mm or more and 0.05 mm or less.

[0046] The shielded flat cable 1 has a first intervening portion 41, a second intervening portion 42, a third intervening portion 43, and a fourth intervening portion 44. The first intervening portion 41, the second intervening portion 42, the third intervening portion 43, and the fourth intervening portion 44 extend in the Y1-Y2 direction. The material of the first intervening portion 41, the second intervening portion 42, the third intervening portion 43, and the fourth intervening portion 44 may be, for example, a polypropylene-based resin. For example, the sum of the thickness of the first insulating layer 21 and the thickness of the first intervening portion 41 or the third intervening portion 43 is 0.4 mm or less, and the sum of the thickness of the second insulating layer 22 and the thickness of the second intervening portion 42 or the fourth intervening portion 44 is 0.4 mm or less. The first intervening portion 41, the second intervening portion 42, the third intervening portion 43, and the fourth intervening portion 44 may not be provided.

[0047] The first interposition 41 is provided between the first insulating layer 21 and the first shield layer 31. The first interposition 41 is between the first ground line 210 and the second ground line 220 in a plan view, and overlaps with the first differential signal line pair 11. In a plan view, an end 41A on the X1 side of the first interposition 41 is between the first differential signal line pair 11 and the first ground line 210, and an end 41B on the X2 side of the first interposition 41 is between the first differential signal line pair 11 and the second ground line 220. A width WI1 of the first interposition 41 is, for example, 3.0 mm or more and 5.0 mm or less. The width WI1 is the distance between the end 41A and the end 41B.

[0048] The second interposition 42 is provided between the second insulating layer 22 and the second shield layer 32. Like the first interposition 41, the second interposition 42 is between the first ground line 210 and the second ground line 220 in a plan view and overlaps with the first differential signal line pair 11. In a plan view, an end 42A on the X1 side of the second interposition 42 is between the first differential signal line pair 11 and the first ground line 210, and an end 42B on the X2 side of the second interposition 42 is between the first differential signal line pair 11 and the second ground line 220. A width WI2 of the second interposition 42 is, for example, 3.0 mm or more and 5.0 mm or less. The width WI2 is the distance between the end 42A and the end 42B.

[0049] The third intervening portion 43 is provided between the first insulating layer 21 and the first shielding layer 31. The third intervening portion 43 is between the first ground line 210 and the third ground line 230 in a plan view, and overlaps with the second differential signal line pair 12. In a plan view, an end portion 43A on the X1 side of the third intervening portion 43 is between the second differential signal line pair 12 and the third ground line 230, and an end portion 43B on the X2 side of the third intervening portion 43 is between the second differential signal line pair 12 and the first ground line 210. A width WI3 of the third intervening portion is, for example, 3.0 mm or more and 5.0 mm or less. The width WI3 is the distance between the end portion 43A and the end portion 43B.

[0050] The fourth interposition 44 is provided between the second insulating layer 22 and the second shield layer 32. As with the third interposition 43, the fourth interposition 44 is between the first ground line 210 and the third ground line 230 in a plan view, and overlaps with the second differential signal line pair 12. In a plan view, an end 44A on the X1 side of the fourth interposition 44 is between the second differential signal line pair 12 and the third ground line 230, and an end 44B on the X2 side of the fourth interposition 44 is between the second differential signal line pair 12 and the first ground line 210. A width WI4 of the fourth interposition 44 is, for example, 3.0 mm or more and 5.0 mm or less. The width WI4 is the distance between the end 44A and the end 44B.

[0051] A first opening 51 reaching the first ground line 210 is formed in the first insulating layer 21. The first opening 51 extends in the Y1-Y2 direction and is formed in a groove shape. A first surface 211 of the first ground line 210 is exposed from the first opening 51. The first shield layer 31 is connected to the first ground line 210 through the first opening 51. Conductive adhesive of the first shield layer 31 Layer 31A is in contact with the first ground line 210. The second surface 212 of the first ground line 210 is entirely covered with the second insulating layer 22.

[0052] A second opening 52 reaching the second ground line 220 is formed in the second insulating layer 22. The second opening 52 extends in the Y1-Y2 direction and is formed in a groove shape. A second surface 222 of the second ground line 220 is exposed from the second opening 52. The second shield layer 32 is connected to the second ground line 220 through the second opening 52. Conductive adhesive of the second shield layer 32 Layer 32A is in contact with the second ground line 220. The first surface 221 of the second ground line 220 is entirely covered with the first insulating layer 21.

[0053] A fourth opening 54 reaching the third ground line 230 is formed in the second insulating layer 22. The fourth opening 54 extends in the Y1-Y2 direction and is formed in a groove shape. The second surface 232 of the third ground line 230 is exposed from the fourth opening 54. The second shield layer 32 is connected to the third ground line 230 through the fourth opening 54. Conductive adhesive of the second shield layer 32 Layer 32A The first 3 Ground Line 2 3 0. The first surface 231 of the third ground line 230 is entirely covered with the first insulating layer 21.

[0054] The shielded flat cable 1 has an insulating protective layer 70 provided on the outside of the shield layer 30. The insulating protective layer 70 covers the shield layer 30. The insulating protective layer 70 has a first insulating protective layer 71 on the Z1 side of the first shield layer 31 and a second insulating protective layer 72 on the Z2 side of the second shield layer 32.

[0055] The shielded flat cable 1 is used by being connected to, for example, a substrate. Here, the connection between the shielded flat cable 1 and the substrate will be described. FIG. 4 is a plan view showing the substrate to which the shielded flat cable 1 is connected. FIGS. 5 to 7 are cross-sectional views showing the substrate to which the shielded flat cable 1 is connected. FIG. 5 corresponds to the cross-sectional view taken along line VV in FIG. 4, FIG. 6 corresponds to the cross-sectional view taken along line VI-VI in FIG. 4, and FIG. 7 corresponds to the cross-sectional view taken along line VII-VII in FIG. 4. The shielded flat cable 1 connected to a substrate is an example of a shielded flat cable with a substrate.

[0056] Substrate 900, which is an example of a substrate to which shielded flat cable 1 is connected, has a first insulating layer 910, a ground layer 920, and a second insulating layer 930. The ground layer 920 is provided on the first insulating layer 910, and the second insulating layer 930 is provided on the ground layer 920. A groove that accommodates a part of the shielded flat cable 1 is formed on the edge of the second insulating layer 930, and an adhesive 990 is provided in the groove.

[0057] A first signal pattern 941, a second signal pattern 942, a third signal pattern 943, a fourth signal pattern 944, a first ground pattern 951, a second ground pattern 952, and a third ground pattern 953 are provided on the second insulating layer 930. The second ground pattern 952, the first signal pattern 941, the second signal pattern 942, the first ground pattern 951, the third signal pattern 943, the fourth signal pattern 944, and the third ground pattern 953 are arranged in this order from the X2 side to the X1 side along the edge where the groove is formed. As shown in FIG. 5, the first ground pattern 951 is electrically connected to the ground layer 920 through a conductive via 921 provided in the second insulating layer 930. As shown in FIG. 7, the third ground pattern 953 is electrically connected to the ground layer 920 through a conductive via 923 provided in the second insulating layer 930. Similarly, the second ground pattern 952 is electrically connected to the ground layer 920 through a conductive via (not shown) provided in the second insulating layer 930 .

[0058] At one end of the shielded flat cable 1, the insulating protective layer 70, the shield layer 30, the first intervening portion 41, the second intervening portion 42, the third intervening portion 43, the fourth intervening portion 44, and the insulating layer 20 are peeled off. This exposes the respective ends of the first ground wire 210, the second ground wire 220, the third ground wire 230, the first signal wire 110, the second signal wire 120, the third signal wire 130, and the fourth signal wire 140. The insulating protective layer 70 is further peeled off, and the respective ends of the first shield layer 31 and the second shield layer 32 are also exposed.

[0059] The second shield layer 32 is connected to the ground layer 920. The first signal line 110 is connected to the first signal pattern 941, the second signal line 120 is connected to the second signal pattern 942, the third signal line 130 is connected to the third signal pattern 943, and the fourth signal line 140 is connected to the fourth signal pattern 944. Furthermore, the first ground line 210 is connected to the first ground pattern 951, the second ground line 220 is connected to the second ground pattern 952, and the third ground line 230 is connected to the third ground pattern 953.

[0060] The connection between the shielded flat cable 1 and the substrate 900 is performed using a bonding material such as solder or a conductive adhesive. For example, as shown in Figs. 5 and 7, the first ground wire 210 is bonded to the first ground pattern 951 by a bonding material 971, and the third ground wire 230 is bonded to the third ground pattern 953 by a bonding material 973. Similarly, the second ground wire 220 is bonded to the second ground pattern 952 by a bonding material (not shown). As shown in Fig. 6, the first signal line 110 is bonded to the first signal pattern 941 by a bonding material 961. Similarly, the second signal line 120, the third signal line 130, and the fourth signal line 140 are bonded to the second signal pattern 942, the third signal pattern 943, and the fourth signal pattern 944 by bonding materials (not shown), respectively. Note that the bonding materials 961, 971, and 973 and the resin 980 are also omitted from Fig. 4.

[0061] The first signal line 110, the second signal line 120, the third signal line 130, and the fourth signal line 140 are preferably connected in a straight line to the first signal pattern 941, the second signal pattern 942, the third signal pattern 943, and the fourth signal pattern 944, respectively. It is preferable that the portions of the first signal line 110, the second signal line 120, the third signal line 130, and the fourth signal line 140 exposed from the insulating protection layer 70 do not include any bent portions. By connecting the first signal line 110 and the second signal line 120 included in the first differential signal line pair 11 in a straight line to the first signal pattern 941 and the second signal pattern 942, respectively, it is possible to reduce the disturbance of the characteristic impedance at the connection portion, and as a result, it is possible to reduce reflection loss and decrease signal deterioration. Similarly, by connecting the third signal line 130 and the fourth signal line 140 included in the second differential signal line pair 12 in a straight line to the third signal pattern 943 and the fourth signal pattern 944, respectively, it is possible to reduce the disturbance of the characteristic impedance at the connection portion, and as a result, it is possible to reduce the reflection loss and less signal degradation.

[0062] Moreover, the first ground line 210, the second ground line 220, and the third ground line 230 are preferably connected in a straight line to the first ground pattern 951, the second ground pattern 952, and the third ground pattern 953, respectively. It is preferable that the portions of the first ground line 210, the second ground line 220, and the third ground line 230 exposed from the insulating protective layer 70 do not include any bent portions. By connecting the first ground line 210, the second ground line 220, and the third ground line 230 in a straight line to the first ground pattern 951, the second ground pattern 952, and the third ground pattern 953, respectively, it is possible to reduce the disturbance of the characteristic impedance at the connection portion, and as a result, it is possible to reduce the reflection loss and the degradation of the signal.

[0063] As shown in FIG. 6, the portion of the first signal line 110 exposed from the insulating protective layer 70 and the bonding material 961 are covered with a resin 980 having a low dielectric constant. The relative dielectric constant of the resin 980 is, for example, 2.0 to 2.6, and preferably 2.1 to 2.5. The resin 980 is, for example, an acrylic ultraviolet curing resin or a bismaleimide ultraviolet curing resin. With this configuration, impedance disturbance can be suppressed. Although not shown, the same applies to the second signal line 120, the third signal line 130, and the fourth signal line 140. Note that the resin 980 is also not shown in FIG. 4.

[0064] 5 and 7, the portion of the first ground line 210 exposed from the insulating protective layer 70, the portion of the third ground line 230 exposed from the insulating protective layer 70, and the bonding materials 971 and 973 are covered with a low-dielectric resin 980. This configuration can suppress impedance disturbance. The same applies to the second ground line 220, although not shown.

[0065] The potential generated in the first ground line 210 is discharged to the first ground pattern 951, the potential generated in the second ground line 220 is discharged to the second ground pattern 952, and the potential generated in the third ground line 230 is discharged to the third ground pattern 953.

[0066] The impedance of the first differential signal line pair 11 is adjusted by the first intervening portion 41 and the second intervening portion 42. The impedance of the second differential signal line pair 12 is adjusted by the third intervening portion 43 and the fourth intervening portion 44.

[0067] In the shielded flat cable 1, the width WG1 of the first ground line 210 is larger than the width WS1 of the first signal line 110, the width WS2 of the second signal line 120, the width WS3 of the third signal line 130, and the width WS4 of the fourth signal line 140. Therefore, the ground potential of the first ground line 210 is stable, and crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12 can be suppressed even in the high frequency range.

[0068] Furthermore, the width WG2 of the second ground line 220 is larger than the width WS1 of the first signal line 110 and the width WS2 of the second signal line 120. Therefore, the ground potential of the second ground line 220 is stable, and the influence of external noise on the first differential signal line pair 11 can be suppressed even in the high frequency range.

[0069] Furthermore, the width WG3 of the third ground line 230 is larger than the width WS3 of the third signal line 130 and the width WS4 of the fourth signal line 140. Therefore, the ground potential of the third ground line 230 is stable, and the influence of external noise on the second differential signal line pair 12 can be suppressed even in the high frequency range.

[0070] In the shielded flat cable 1, the first shield layer 31 is connected to the first ground wire 210 through the first opening 51. Therefore, the ground potential of the first ground wire 210 can be stabilized without contacting the second shield layer 32 with the first ground wire 210. Furthermore, since there is no need to process the second insulating layer 22 to connect the second shield layer 32 to the first ground wire 210, the number of steps and costs can be reduced.

[0071] Moreover, the second shield layer 32 is connected to the second ground line 220 through the second opening 52. Therefore, the ground potential of the second ground line 220 can be stabilized without contacting the first shield layer 31 with the second ground line 220. Furthermore, since there is no need to process the first insulating layer 21 to connect the first shield layer 31 to the second ground line 220, the number of steps and costs can be reduced.

[0072] Similarly, the second shield layer 32 is connected to the third ground line 230 through the fourth opening 54. Therefore, the ground potential of the third ground line 230 can be stabilized without contacting the first shield layer 31 with the third ground line 230. Furthermore, since it is not necessary to process the first insulating layer 21 to connect the first shield layer 31 to the third ground line 230, the number of steps and costs can be reduced.

[0073] It is preferable that the width WG1 of the first ground line 210 and the width WG2 of the second ground line 220 are larger than the width WT1 of the first differential signal line pair 11. When this relationship is satisfied, it is easy to stabilize the ground potential of the first ground line 210 and the second ground line 220. Therefore, it is easy to suppress crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12, and it is easy to suppress the influence of external noise on the first differential signal line pair 11. In addition, when manufacturing the shielded flat cable 1, it is easy to bring the first shield layer 31 into contact with the first ground line 210, and the second shield layer 32 into contact with the second ground line 220. The width WT1 of the first differential signal line pair 11 is the distance between the fourth surface 114 of the first signal line 110 and the third surface 123 of the second signal line 120.

[0074] Similarly, the width WG1 of the first ground line 210 and the width WG3 of the third ground line 230 are preferably larger than the width WT2 of the second differential signal line pair 12. When this relationship is satisfied, the ground potential of the first ground line 210 and the third ground line 230 is easily stabilized. Therefore, crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12 is easily suppressed, and the influence of external noise on the second differential signal line pair 12 is easily suppressed. In addition, when manufacturing the shielded flat cable 1, the first shield layer 31 is easily brought into contact with the first ground line 210, and the second shield layer 32 is easily brought into contact with the third ground line 230. The width WT2 of the second differential signal line pair 12 is the distance between the fourth surface 134 of the third signal line 130 and the third surface 143 of the fourth signal line 140.

[0075] The distance LTG1 between the first differential signal line pair 11 and the first ground wire 210 and the distance LTG2 between the first differential signal line pair 11 and the second ground wire 220 are preferably greater than the distance LSS1 between the first signal line 110 and the second signal line 120. When this relationship holds, the first shield layer 31 is easily brought into contact with the first ground wire 210 and the second shield layer 32 is easily brought into contact with the second ground wire 220 during the manufacture of the shielded flat cable 1. The distance LTG1 between the first differential signal line pair 11 and the first ground wire 210 is the distance between the third surface 123 of the second signal line 120 and the fourth surface 214 of the first ground wire 210. The distance LTG2 between the first differential signal line pair 11 and the second ground wire 220 is the distance between the fourth surface 114 of the first signal line 110 and the third surface 223 of the second ground wire 220.

[0076] Moreover, the distance LTG3 between the second differential signal line pair 12 and the first ground wire 210 and the distance LTG4 between the second differential signal line pair 12 and the third ground wire 230 are preferably greater than the distance LSS2 between the third signal line 130 and the fourth signal line 140. When this relationship holds, the first shield layer 31 is easily brought into contact with the first ground wire 210 and the second shield layer 32 is easily brought into contact with the third ground wire 230 during the manufacture of the shielded flat cable 1. The distance LTG3 between the second differential signal line pair 12 and the first ground wire 210 is the distance between the fourth surface 134 of the third signal line 130 and the third surface 213 of the first ground wire 210. The distance LTG4 between the second differential signal line pair 12 and the third ground wire 230 is the distance between the third surface 143 of the fourth signal line 140 and the fourth surface 234 of the third ground wire 230.

[0077] It is preferable that the width WT1 of the first differential signal line pair 11 is larger than the distance LTG1 between the first differential signal line pair 11 and the first ground line and the distance LTG2 between the first differential signal line pair 11 and the second ground line 220. When this relationship holds, crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12 is easily suppressed, and the influence of external noise on the first differential signal line pair 11 is easily suppressed.

[0078] Similarly, the width WT2 of the second differential signal line pair 12 is preferably larger than the distance LTG3 between the second differential signal line pair 12 and the first ground line and the distance LTG4 between the second differential signal line pair 12 and the third ground line 230. When this relationship holds, crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12 is easily suppressed, and the influence of external noise on the second differential signal line pair 12 is easily suppressed.

[0079] The width WG1 of the first ground line 210 is preferably larger than the distance LTG1 between the first differential signal line pair 11 and the first ground line 210, and the width WG2 of the second ground line 220 is preferably larger than the distance LTG2 between the first differential signal line pair 11 and the second ground line 220. When this relationship is established, it is easy to stabilize the ground potential of the first ground line 210 and the second ground line 220. Therefore, it is easy to suppress crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12, and it is easy to suppress the influence of external noise on the first differential signal line pair 11. In addition, when manufacturing the shielded flat cable 1, it is easy to make the first shield layer 31 contact the first ground line 210 and the second shield layer 32 contact the second ground line 220. The width WG1 is more preferably 1.4 times or more the distance LTG1, and the width WG2 is more preferably 1.4 times or more the distance LTG2.

[0080] The width WG1 of the first ground line 210 is preferably larger than the distance LTG3 between the second differential signal line pair 12 and the first ground line 210, and the width WG3 of the third ground line 230 is preferably larger than the distance LTG4 between the second differential signal line pair 12 and the third ground line 230. When this relationship is established, it is easy to stabilize the ground potential of the first ground line 210 and the third ground line 230. Therefore, it is easy to suppress crosstalk between the first differential signal line pair 11 and the second differential signal line pair 12, and it is easy to suppress the influence of external noise on the second differential signal line pair 12. In addition, when manufacturing the shielded flat cable 1, it is easy to bring the first shield layer 31 into contact with the first ground line 210, and the second shield layer 32 into contact with the third ground line 230. The width WG3 is more preferably 1.4 times or more the distance LTG3.

[0081] It is preferable that the width WG1 of the first ground line 210 and the width WG2 of the second ground line 220 are smaller than the width WI1 of the first intervening portion 41 and the width WI2 of the second intervening portion 42. When this relationship holds, the impedance of the first differential signal line pair 11 is easy to adjust.

[0082] It is preferable that the width WG1 of the first ground line 210 and the width WG3 of the third ground line 230 are smaller than the width WI3 of the third intervening portion 43 and the width WI4 of the fourth intervening portion 44. When this relationship holds, the impedance of the second differential signal line pair 12 is easy to adjust.

[0083] When a desired impedance is obtained, the first intervening portion 41, the second intervening portion 42, the third intervening portion 43, and the fourth intervening portion 44 do not have to be provided.

[0084] Second embodiment A second embodiment will now be described. Fig. 8 is a cross-sectional view showing a shielded flat cable according to the second embodiment. Fig. 8, like Fig. 2, corresponds to a cross-sectional view taken along line II-II in Fig. 1.

[0085] As shown in Fig. 8, in the shielded flat cable 2 according to the second embodiment, in addition to the second opening 52 and the fourth opening 54, a third opening 53 reaching the first ground wire 210 is formed in the second insulating layer 22. The third opening 53 extends in the Y1-Y2 direction and is formed in a groove shape. The second surface 212 of the first ground wire 210 is exposed from the third opening 53. The second shield layer 32 is connected to the first ground wire 210 through the third opening 53. Conductive adhesive of the second shield layer 32 Layer 32A is in contact with the first ground line 210.

[0086] In addition to the first opening 51, the first insulating layer 21 is formed with a fifth opening 55 reaching the second ground line 220 and a sixth opening 56 reaching the third ground line 230. The fifth opening 55 and the sixth opening 56 extend in the Y1-Y2 direction and are formed in a groove shape. The first surface 221 of the second ground line 220 is exposed from the fifth opening 55. The first shield layer 31 is connected to the second ground line 220 through the fifth opening 55. Conductive adhesive of the first shield layer 31 Layer 31A is in contact with the second ground line 220. The first surface 221 of the third ground line 230 is exposed from the sixth opening 56. The first shield layer 31 is connected to the third ground line 230 through the sixth opening 56. The conductive adhesive of the first shield layer 31 Layer 31A is in contact with the third ground line 230 .

[0087] The other configuration is similar to that of the first embodiment.

[0088] According to the second embodiment, similarly to the first embodiment, the influence of external noise and crosstalk can be suppressed even in the high frequency range.

[0089] Third embodiment A third embodiment will now be described. Fig. 9 is a cross-sectional view showing a shielded flat cable according to the third embodiment. Fig. 9, like Fig. 2, corresponds to a cross-sectional view taken along line II-II in Fig. 1.

[0090] 9, in the shielded flat cable 3 according to the third embodiment, the first shield layer 31 and the second shield layer 32 protrude from both ends of the insulating layer 20 in the X1-X2 direction and are joined to each other at the protruding portions. Also, the first insulating protective layer 71 and the second insulating protective layer 72 protrude from both ends of the shield layer 30 in the X1-X2 direction and are joined to each other at the protruding portions.

[0091] The other configuration is similar to that of the second embodiment.

[0092] According to the third embodiment, it is possible to suppress the influence of external noise and crosstalk even in the high frequency range, similarly to the second embodiment, and further, according to the third embodiment, a higher shielding performance than that of the second embodiment can be obtained.

[0093] As in the first embodiment, the fifth opening 55 and the sixth opening 56 do not have to be formed in the first insulating layer 21, and the third opening 53 does not have to be formed in the second insulating layer 22.

[0094] (Fourth embodiment) A fourth embodiment will now be described. Fig. 10 is a cross-sectional view showing a shielded flat cable according to the fourth embodiment. Fig. 10 corresponds to a cross-sectional view taken along line II-II in Fig. 1, similar to Fig. 2.

[0095] As shown in FIG. 10, the shielded flat cable 4 according to the fourth embodiment does not include the second differential signal line pair 12 and the third ground line 230, and the dimension in the X1-X2 direction is accordingly smaller.

[0096] The other configuration is similar to that of the first embodiment.

[0097] In the fourth embodiment, no crosstalk occurs within the shielded flat cable 4. Furthermore, similar to the first embodiment, the influence of external noise on the first differential signal line pair 11 can be suppressed.

[0098] As in the second embodiment, an opening reaching the second ground line 220 may be formed in the first insulating layer 21, and an opening reaching the first ground line 210 may be formed in the second insulating layer 22.

[0099] Fifth embodiment A fifth embodiment will now be described. Fig. 11 is a cross-sectional view showing a shielded flat cable according to the fifth embodiment. Fig. 11 corresponds to a cross-sectional view taken along line II-II in Fig. 1, similar to Fig. 2.

[0100] 11, the shielded flat cable 5 according to the fifth embodiment has a first power line 310, a second power line 320, and a third power line 330. The first power line 310, the second power line 320, and the third power line 330 extend in the Y1-Y2 direction and are aligned in the X1-X2 direction on the imaginary plane 10.

[0101] The first power line 310 is on the X1 side of the third ground line 230, the second power line 320 is on the X1 side of the first power line 310, and the third power line 330 is on the X1 side of the second power line 320. The first power line 310, the second power line 320, and the third power line 330 are made of soft copper with a tin-plated layer formed on the surface. The first power line 310, the second power line 320, and the third power line 330 are, for example, rectangular conductors. The first power line 310, the second power line 320, and the third power line 330 are used to transmit power.

[0102] The first power line 310, the second power line 320, and the third power line 330 are covered with the insulating layer 20. The shield layer 30 and the insulating protective layer 70 do not have to cover the first power line 310, the second power line 320, and the third power line 330.

[0103] The other configuration is similar to that of the first embodiment.

[0104] According to the fifth embodiment, similarly to the first embodiment, the influence of external noise and crosstalk can be suppressed even in the high frequency range.

[0105] As in the second embodiment, the fifth opening 55 and the sixth opening 56 may be formed in the first insulating layer 21, and the third opening 53 may be formed in the second insulating layer 22.

[0106] Sixth embodiment A sixth embodiment will now be described. Fig. 12 is a cross-sectional view showing a shielded flat cable according to the sixth embodiment. Fig. 12 corresponds to a cross-sectional view taken along line II-II in Fig. 1, similar to Fig. 2.

[0107] 12, in the shielded flat cable 6 according to the sixth embodiment, the shield layer 30 is composed of a single third shield layer 33. The third shield layer 33 covers the Z1 side surface of the first insulating layer 21 and the Z2 side surface of the second insulating layer 22 via the X2 side ends of the first insulating layer 21 and the second insulating layer 22. The first insulating protective layer 71 and the second insulating protective layer 72 protrude from the third shield layer 33 on the X2 side and are joined to each other at the protruding portions.

[0108] The other configuration is similar to that of the fifth embodiment.

[0109] The sixth embodiment also provides the same effects as the fifth embodiment. Moreover, the sixth embodiment provides a more excellent shielding property at the end on the X2 side.

[0110] In any of the embodiments, the connection form of the signal lines to the substrate 900 is not limited to the above.

[0111] For example, on the Z1 side of the first signal wire 110, a part of the first insulating protective layer 71 may remain at the tip of the shielded flat cable 1. Also, on the Z2 side of the first signal wire 110, the second insulating protective layer 72 may remain without being peeled off. The same applies to the second signal wire 120, the third signal wire 130, and the fourth signal wire 140.

[0112] In the present disclosure, the ground wires and the signal wires are not limited to rectangular conductors or round conductors. For example, the cross-sectional shape of the ground wires and the signal wires perpendicular to the longitudinal direction may be an ellipse or another polygon.

[0113] Although the embodiments have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes are possible within the scope of the claims. [Explanation of symbols]

[0114] 1, 2, 3, 4, 5, 6: Shielded flat cable 10: Virtual plane 11: First differential signal line pair 12: Second differential signal line pair 20: Insulating layer 21: First insulating layer 22: Second insulating layer 21A, 22A: Adhesive layer 21B, 22B: Base material 30: Shield layer 31: First shield layer 32: Second shield layer 31A, 32A: Conductive adhesive layer 31B, 32B: Metal foil 33: 3rd shield layer 41:First intervention 42:Second intervention 43: Third intervention 44:Fourth intervention 41A, 41B, 42A, 42B, 43A, 43B, 44A, 44B: Ends 51: First opening 52: Second opening 53: 3rd opening 54: 4th opening 55: 5th opening 56: 6th opening 70: Insulating protective layer 71: First insulating protective layer 72: Second insulating protection layer 110: First signal line 120: Second signal line 130: 3rd signal line 140: 4th signal line 111, 121, 131, 141, 211, 221, 231: 1st side 112, 122, 132, 142, 212, 222, 232: 2nd side 113, 123, 133, 143, 213, 223, 233: Third side 114, 124, 134, 144, 214, 224, 234: 4th side 210: First Grand Line 220: Second Grand Line 230: Third Grand Line 310: First power line 320: Second power line 330: 3rd power line 900: Substrate 910: First insulating layer 930: Second insulating layer 920: Ground layer 921, 923: Conductive vias 941: First signal pattern 942: Second signal pattern 943: 3rd signal pattern 944: 4th signal pattern 951: First Grand Pattern 952: Second Grand Pattern 953: 3rd Grand Pattern 961, 971, 973: Bonding material 980: Resin 990: Adhesive

Claims

1. A shielded flat cable, a substrate to which an end of the shielded flat cable is connected; having The shielded flat cable is a first differential signal line pair including a first signal line and a second signal line parallel to each other; a first ground line parallel to the first differential signal line pair; a second ground line that is parallel to the first differential signal line pair and that disposes the first differential signal line pair between the first ground line and the second ground line; an insulating layer covering the first differential signal line pair, the first ground line, and the second ground line; a first shield layer covering a first surface of the insulating layer; a second shield layer that is opposite to the first surface and covers a second surface of the insulating layer; having a first opening exposing the first ground line is formed on the first surface side of the insulating layer; the first shield layer is connected to the first ground line through the first opening, a width of the first ground line is larger than a width of the first signal line and a width of the second signal line; a resin that covers the first ground line, the second ground line, and the first differential signal line pair, the first ground line and the second ground line being exposed from the insulating layer at the end portions; The resin has a relative dielectric constant of 2.0 or more and 2.6 or less.

2. 2 . The shielded flat cable with substrate according to claim 1 , wherein the first ground wire is entirely overlapped with the second shield layer via the insulating layer on the second surface side.

3. a second opening exposing the second ground line is formed on the second surface side of the insulating layer; the second shield layer is connected to the second ground line through the second opening, 3. The shielded flat cable with substrate according to claim 1, wherein the second ground wire is entirely overlapped with the first shield layer via the insulating layer on the first surface side.

4. 2. The substrate-attached shielded flat cable according to claim 1, wherein a third opening exposing the first ground wire is formed on the second surface side of the insulating layer, and the second shielding layer is connected to the first ground wire via the third opening.

5. a second opening exposing the second ground line is formed on the second surface side of the insulating layer; the second shield layer is connected to the second ground line through the second opening, the second ground line entirely overlaps with the first shield layer via the insulating layer on the first surface side; 2. The substrate-attached shielded flat cable according to claim 1, wherein a third opening exposing the first ground wire is formed on the second surface side of the insulating layer, and the second shielding layer is connected to the first ground wire via the third opening.

6. 6. A shielded flat cable with substrate as described in any one of claims 1 to 5, wherein, in a cross-sectional view perpendicular to the longitudinal direction, the first shielding layer and the second shielding layer protrude from at least one end side of the insulating layer and are joined to each other at the protruding portions.

7. 7. The shielded flat cable with substrate according to claim 1, wherein a width of the first ground line is larger than a width of the first differential signal line pair.

8. 8. The shielded flat cable with substrate according to claim 1, wherein a distance between the first differential signal line pair and the first ground line is greater than a distance between the first signal line and the second signal line.

9. 9. The shielded flat cable with substrate according to claim 1, wherein a width of the first differential signal line pair is greater than a distance between the first differential signal line pair and the first ground line.

10. 10. The shielded flat cable with substrate according to claim 1, wherein a width of the first ground wire is larger than a distance between the first differential signal line pair and the first ground wire.

11. an intervening portion is provided between the first shield layer and the insulating layer, the intervening portion being parallel to the first differential signal line pair and overlapping the first differential signal line pair in a plan view; 11. The shielded flat cable with substrate according to claim 1, wherein a width of the first ground line is smaller than a width of the intermediate portion.

12. a second differential signal line pair including a third signal line and a fourth signal line parallel to the first differential signal line pair; the insulating layer covers the second differential signal line pair; 12. The shielded flat cable with substrate according to claim 1, wherein the first ground wire is disposed between the first differential signal line pair and the second differential signal line pair.

13. A shielded flat cable, a substrate to which an end of the shielded flat cable is connected; having The shielded flat cable is a first differential signal line pair including a first signal line and a second signal line parallel to each other; a second differential signal line pair including a third signal line and a fourth signal line parallel to the first differential signal line pair; a first ground line parallel to the first differential signal line pair; a second ground line parallel to the first differential signal line pair; an insulating layer covering the first differential signal line pair, the second differential signal line pair, the first ground line, and the second ground line; a shield layer covering the insulating layer; having the first differential signal line pair, the second differential signal line pair, the first ground line, and the second ground line are arranged on an imaginary plane, the first ground line is disposed between the first differential signal line pair and the second differential signal line pair; the first differential signal line pair is disposed between the first ground line and the second ground line, a first opening reaching the first ground line and a second opening reaching the second ground line are formed in the insulating layer; the first opening is formed only on a first direction side of the first ground line perpendicular to the imaginary plane, a surface of the first ground line on a second direction side opposite to the first direction side is entirely covered with the insulating layer; the second opening is formed only on the second direction side of the second ground line, a surface of the second ground line in the first direction is entirely covered with the insulating layer, the shield layer is connected to the first ground line through the first opening and to the second ground line through the second opening, a width of the first ground line and a width of the second ground line are larger than a width of the first signal line, a width of the second signal line, a width of the third signal line, and a width of the fourth signal line; a resin that covers the first ground line, the second ground line, and the first differential signal line pair, the first ground line and the second ground line being exposed from the insulating layer at the end portions; The resin has a relative dielectric constant of 2.0 or more and 2.6 or less.

14. The substrate, a first ground pattern to which the first ground line is electrically connected; a second ground pattern to which the second ground line is electrically connected; a first signal pattern and a second signal pattern to which the first differential signal line pair is electrically connected; The shielded flat cable with substrate according to claim 1 , further comprising:

15. 15. The shielded flat cable with substrate according to claim 1, wherein the first differential signal line pair exposed from the insulating layer is connected in a straight line to the first signal pattern and the second signal pattern.

16. 16. The shielded flat cable with substrate according to claim 1, wherein the first ground wire exposed from the insulating layer is connected in a straight line to the first ground pattern.

Images