TWM628419U - Improved structure of bus line - Google Patents

Abstract

The present invention relates to an improved structure for an arrangement of wires, which comprises an arrangement of wires. The arrangement of wires is sequentially laminated with a conductor layer, a foam layer, a metal layer and an insulating layer, wherein the conductor layers include a plurality of signals spaced apart from each other. and the foam layer is a polyethylene layer; accordingly, the improved cable structure of the present invention can still maintain the advantage of high-speed transmission efficiency even when the thickness of the cable is reduced.

Description

Improved cable structure

The present invention belongs to the technical field of signal transmission, and particularly refers to an improved cable structure that can maintain high-speed transmission efficiency even when the thickness of the cable is reduced by changing the material of the foam layer of the cable.

The general improved structure of the cable includes a cable (such as a PCIE standard busbar, a SATA standard busbar and other signal transmission lines used in computers) and connectors arranged at both ends of the cable. The connectors are electrically connected to the cable. Connect to the corresponding connector of the external device (such as the corresponding male and female connectors), and the signal is transmitted between the external devices through the signal line in the cable and through the connector.

Please refer to Figure 1 and Figure 2 at the same time, wherein Figure 1 is a plan view of a conventional flat cable, and Figure 2 is a cross-sectional view taken from the section A-A of Figure 3 . As shown in FIG. 1 and FIG. 2, the conventional flat cable 9 is laminated with a conductor layer 91, a foam layer 92, a metal layer 93, an insulating layer 94, etc., and the conductor layer 91 is provided with a plurality of signal lines 911 and a plurality of Ground wire 912. In a conventional practice, two signal lines 911 are matched with a ground line 912 to repeatedly form a flat line 9 with a specified width, for example, a flat line 9 with a normal width of forty-eight lines or seventy-two lines.

As mentioned above, since the conductor layer 91 of the conventional flat cable 9 has the ground line 912 , the width of the signal line 911 is limited under the condition that the flat line 9 has a specification width, thereby reducing the transmission rate. Therefore, the structure of the flat cable 9 must be properly designed, and the so-called skin effect and characteristic impedance must be considered in the design.

The above-mentioned skin effect is also called the skin effect, which is a phenomenon in which the current distribution inside the conductor is not uniform when there is alternating current or alternating electromagnetic field in the conductor (such as the signal line 911). Increase, the current density in the conductor decays exponentially, that is, the current in the conductor will be concentrated on the surface of the conductor, when viewed from a cross-section perpendicular to the current direction, almost no current flows in the central part of the conductor, only in the conductor. There will be current in the edge part, in short, the current is concentrated in the skin part of the conductor. Because the skin effect system makes the alternating current only pass through the surface of the conductor, the current only produces a thermal effect on the surface of the conductor, so for example, in the iron and steel industry, the skin effect can be used to quench the steel surface to increase the hardness of the steel surface. big. The method of alleviating the skin effect can be, for example, using the so-called Litz wire, that is, a plurality of metal wires are intertwined with each other, so that the electromagnetic field can be distributed more evenly;

In addition, the above-mentioned characteristic impedance refers to the resistance encountered when a high-frequency signal or electromagnetic wave propagates in a conductor, measured in ohms. The fluctuation difference of the impedance value in the conductor must be controlled so that the signal can be transmitted at the correct speed. For transmission lines formed by different types of conductors (such as coaxial transmission lines, linear transmission lines, microstrip transmission lines, coplanar transmission lines, etc.) , there will be different impedance calculation formulas. Impedance control can be achieved by changing different design conditions, such as changing the material, thickness and dielectric constant of the foam layer in the transmission line.

However, due to the influence of the material used in the conventional flat cable 9, in order to accommodate the transmission efficiency, for example, to control the impedance, the flat wire 9 has a thicker thickness.

In order to solve the problem of increasing the thickness of the conventional cable due to the use of materials in order to accommodate the transmission rate, the improved cable structure proposed by the present invention changes the material of the foam layer of the cable to increase the thickness of the cable. In the case of thinning, high-speed transmission efficiency can still be maintained.

The improved cable structure proposed by the present invention includes a cable, the cable is sequentially laminated with a conductor layer, a foam layer, a metal layer and an insulating layer, the conductor layer includes a plurality of signal lines spaced apart from each other, and The material of the foam layer is polyethylene (PE, Polyethylene).

As mentioned above, in the structural design of the improved cable structure proposed by the present invention, the foam layer of the cable is a polyethylene layer. Since the dielectric constant of polyethylene is small, the impedance value obtained is calculated according to the impedance formula. It will become larger, and the thickness of the relative cable will become thinner. In other words, the high-speed transmission efficiency can still be maintained even when the thickness of the cable is reduced.

Optionally, in a non-limiting exemplary embodiment, the cable further includes a film layer, which is laminated between the conductor layer and the foam layer.

Optionally, in a non-limiting exemplary embodiment, the material of the film layer is polyethylene terephthalate (PET, Polyethylene Terephthalate).

Optionally, in a non-limiting exemplary embodiment, further, the cable is sequentially laminated with the film layer, the foam layer, the metal layer and the insulating layer from the conductor layer to the upper and lower sides. Floor.

Optionally, in a non-limiting exemplary embodiment, between the conductor layer and the film layer, between the film layer and the foam layer, between the foam layer and the metal layer, and the A glue layer is used for bonding between the metal layer and the insulating layer.

Optionally, in a non-limiting exemplary embodiment, the conductor layer further includes a plurality of ground lines spaced apart from each other.

Optionally, in a non-limiting exemplary embodiment, the plurality of signal lines are arranged in a single row.

Optionally, in a non-limiting exemplary embodiment, the plurality of signal lines are arranged in a double row.

Optionally, in a non-limiting exemplary embodiment, the flat cable is a Flexible Flat Cable (FFC).

In the following, the technical content of the present invention, its advantages and achievable effects will be further described in the form of preferred specific embodiments in conjunction with the accompanying drawings. used for restriction.

Please refer to FIG. 3 , which is a perspective view of the first preferred embodiment of the new type. In Figure 3, a signal transmission device 7 is shown, which includes a cable modification structure 1, and the cable modification structure 1 includes a cable 2. In this embodiment, the cable 2 is a flexible flat cable (FFC), of course, it is not limited to this, for example, the flexible printed circuit (FPC, Flexible Printed Circuitry) can also be used for the cable 2 .

In addition, the signal transmission device 7 further includes a connector 3 and a circuit board 5 , wherein the circuit board 5 includes a plurality of signal conductor lines 51 and a plurality of ground conductor lines 52 arranged at intervals from each other. The connector 3 is connected to the connection between the cable 2 and the circuit board 5, and is electrically connected to other electrical equipment (not shown).

Please refer to FIG. 4 , which is a cross-sectional view of the first preferred embodiment of the new type. As shown in FIG. 4 , the cable 2 is sequentially laminated from a conductor layer 21 to the upper and lower sides with a film layer 26 (such as PET material), a foam layer 24 , a metal layer 22 and an insulating layer 23 , and A glue layer 25 is used for bonding between the aforementioned layers; in detail, between the conductor layer 21 and the film layer 26, between the film layer 26 and the foam layer 24, The adhesive layer 25 is used for bonding between the metal layers 22 and between the metal layer 22 and the insulating layer 23 respectively.

As also shown in FIG. 4 , the conductor layer 21 of the cable 2 includes a plurality of signal lines 211 spaced apart from each other. In this embodiment, the plurality of signal lines 211 are arranged in a single row. In addition, the foam layer 24 of the cable 2 is a polyethylene layer.

The following formula (I) is the transmission characteristic impedance formula of the improved structure of the cable:

為特性阻抗(characteristic impedance)、

為介電常數、W為線寬、H為絕緣層高度、T為導電層的厚度。於上述之排線改良結構1中，係將排線2之發泡體層24改變為聚乙烯層，由聚乙烯層之材質特性可知，聚乙烯之介電常數小，依照對於排線2之阻抗公式計算，可得到變大的阻抗值，再依照計算公式可知，排線2之厚度相對地就會變薄（小）。換言之，將排線2之發泡體層24之材質改變為聚乙烯的設計方式可使排線2在厚度變薄的情況下仍舊可以維持高速之傳輸效率。 in

is the characteristic impedance,

is the dielectric constant, W is the line width, H is the height of the insulating layer, and T is the thickness of the conductive layer. In the above-mentioned cable modification structure 1, the foam layer 24 of the cable 2 is changed to a polyethylene layer. From the material properties of the polyethylene layer, it can be known that the dielectric constant of polyethylene is small, according to the impedance of the cable 2. According to the formula calculation, the larger impedance value can be obtained, and then according to the calculation formula, the thickness of the cable 2 will be relatively thinner (smaller). In other words, by changing the material of the foam layer 24 of the flexible cable 2 to polyethylene, the flexible cable 2 can still maintain high-speed transmission efficiency even when the thickness of the flexible cable 2 is reduced.

Please refer to FIG. 5 , which is a cross-sectional view of the second preferred embodiment of the present invention. In this embodiment, the main structures thereof are the same as those of the first preferred embodiment, but the difference is that the plurality of signal lines 211 of the conductor layer 21 of the cable 2 are arranged in double rows in this embodiment.

Please refer to FIG. 6 , which is a cross-sectional view of the third preferred embodiment of the present invention. In this embodiment, its main structure is the same as the above-mentioned first preferred embodiment, but the difference is that the conductor layer 21 of the flat cable 2 further includes a plurality of ground wires 212 spaced apart from each other, and the plurality of ground wires 212 are connected to A plurality of signal lines 211 arranged in a single row are spaced apart from each other, that is, a signal line 211 , a ground line 212 , and another signal line 211 are arranged in sequence.

Please refer to FIG. 7 , which is a cross-sectional view of the fourth preferred embodiment of the present invention. In this embodiment, its main structure is the same as the above-mentioned second preferred embodiment, but the difference is that the conductor layer 21 of the flat cable 2 further includes a plurality of ground wires 212 spaced apart from each other, and the plurality of ground wires 212 are connected to A plurality of signal lines 211 arranged in double rows are spaced apart from each other, that is, a pair of signal lines 211 , a ground line 212 , and another pair of signal lines 211 are arranged in sequence.

The above are only preferred specific embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

1: Cable improvement structure 2: Cable 21: Conductor layer 211: Signal line 212: ground wire 22: Metal layer 23: Insulation layer 24: Foam layer 25: Adhesive layer 26: Epithelial layer 3: Connector 5: circuit board 51: Signal conduction line 52: Ground conductor 7: Signal transmission device 9: Cable 91: Conductor layer 911: Signal line 912: Ground wire 92: foam layer 93: Metal layer 94: Insulation layer

Figure 1 is a plan view of a conventional cable.

FIG. 2 is a cross-sectional view taken from the section A-A of FIG. 1 .

FIG. 3 is a perspective view of the first preferred embodiment of the novel.

FIG. 4 is a cross-sectional view of the first preferred embodiment of the novel.

Fig. 5 is a cross-sectional view of the second preferred embodiment of the novel.

FIG. 6 is a cross-sectional view of the third preferred embodiment of the novel.

FIG. 7 is a cross-sectional view of the fourth preferred embodiment of the novel.

1: Cable improvement structure

2: Cable

21: Conductor layer

211: Signal line

22: Metal layer

23: Insulation layer

24: Foam layer

25: Adhesive layer

26: Epithelial layer

Claims (9)

An improved structure for a flat cable, comprising: A cable (2), a conductor layer (21), a foam layer (24), a metal layer (22) and an insulating layer (23) are laminated in sequence, the conductor layers (21) include a plurality of numbers spaced apart from each other A signal line (211) is provided, and the foam layer (24) is a polyethylene layer. The improved structure of the cable according to claim 1, wherein the cable (2) further comprises a film layer (26), which is laminated between the conductor layer (21) and the foam layer (24). The improved cable structure according to claim 2, wherein the material of the film layer (26) is polyethylene terephthalate. The improved structure of the cable according to claim 2, further, the cable (2) is sequentially laminated with the film layer (26) and the foam layer (24) from the conductor layer (21) to the upper and lower sides. ), the metal layer (22) and the insulating layer (23). The improved cable structure according to claim 4, wherein between the conductor layer (21) and the film layer (26), between the film layer (26) and the foam layer (24), and between the foam layer A glue layer (25) is used for bonding between (24) and the metal layer (22), and between the metal layer (22) and the insulating layer (23). The improved cable structure according to any one of claims 1 to 5, wherein the conductor layer (21) further comprises a plurality of ground wires (212) spaced apart from each other. The improved cable structure according to any one of claims 1 to 5, wherein the plurality of signal lines (211) are arranged in a single row. The improved cable structure according to any one of claims 1 to 5, wherein the plurality of signal lines (211) are arranged in double rows. The improved cable structure according to any one of claims 1 to 5, wherein the cable (2) is a flexible flat cable.

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