TW201907625A - Micro-thin dual channel flexible circuit bridging wire matches requirement of characteristic impedance and capable of reducing high frequency signal reflection and skin effect of transmission process - Google Patents

Abstract

The disclosure provides a micro-thin dual channel flexible circuit bridging wire comprising a dual channel flexible circuit board and a first connection interface and a second connection interface, which form electrical connection, disposed at two sides of the dual channel flexible circuit board. The dual channel flexible circuit board sequentially comprises a first insulation layer, a first wire layer, a second insulation layer, a grounding layer, a third insulation layer, a second wire layer and a fourth insulation layer. By utilizing the dual channel flexible circuit board having thinner and stronger flexibility endurance, the first connection interface and the second connection surface can couple two expansion interface cards having different intervals to form bridging state, and the grounding layer between the first wire layer and the second wire layer is taken as a common reference interface of dual channel high frequency signal transmission. With respect to integrity of high frequency signal, the requirement of working bandwidth and characteristic impedance can be satisfied to reduce correspondingly generated electromagnetic wave interference during high frequency signal transmission, thereby further achieving effects of stable dual channel high frequency signal transmission and improving transmission efficiency.

Description

 Micro-thin dual-channel flexible circuit bridge wiring  

The invention provides a micro-thin double-channel flexible circuit bridge connection, in particular, a two-channel flexible circuit board can be used to connect two expansion interface cards of different pitches to form a bridge state, and meet the requirements of high-frequency signal transmission characteristic impedance and can reduce electromagnetic interference. In order to achieve stable dual-channel high-frequency signal transmission and improve transmission efficiency.

According to the rapid development of electronic technology, the speed and performance of computers and servers are getting faster and faster. In addition to the central processing unit and memory on the motherboard as the information processing hub in the computer or server, Various peripheral devices such as screens and data devices are also the focus of screen display, data transmission and command control of electronic devices such as computers and servers. You can use the slots on the motherboard to install various types of interface cards to enable peripheral devices. Transfer data between the interface card and the electronic device and use it for expansion purposes.

Furthermore, as people continue to pursue the image of the screen, the resolution and performance requirements of the display interface are getting higher and higher, and some manufacturers have developed an expandable interface that can bridge two display cards and use them as a single output. Scalable Link Interface (SLI) technology is mainly used to install display cards in two slots arranged side by side on the motherboard supporting SLI technology, and a bridge connector at the top of each display card. The plurality of connector blocks of the graphics card bridge are respectively connected to the bridge terminals of the two display cards to form a bridge state, so that the motherboard can use the image processor on the two display cards for Parallel Computing and 3D graphics. Processing to achieve the best graphics display performance, but with the advancement of integrated circuit technology, the hardware architecture of dual graphics cards has gradually declined, until the emerging virtual reality and hybrid real-world technologies are becoming more prevalent, in order to deal with more complex The functions of computing and graphics acceleration, dual-card bridging technology has once again been valued, mainly used in the current mainstream of fast peripheral components Even (Peripheral Component Interconnect Express, referred to as PCI Express) standard to address the problem of early expansion bus interface inadequate transport infrastructure and insufficient use of bandwidth, the dual graphics cards can play full high-speed graphics display performance via SLI technology.

However, the existing dual graphics bridges on the market can be roughly divided into single-channel soft-slab bridges, single-channel or dual-channel hard-board bridges, wherein the traditional two-channel soft-board bridges have a soft layer on the lower layer of the signal layer. For the insulating layer, due to the soft substrate manufacturing process and the physical arrangement of the wiring layout and structure, the double-layer flexible board can not be designed according to the high transmission rate and high-efficiency design trend, and is easy to generate in high-speed transmission applications. The skin effect of high-frequency signal reflection and transmission process, while the use of multi-layer soft board structure can use the power layer and ground plane of the middle two layers to improve electrical characteristics (such as characteristic impedance), but with the high frequency of multi-layer soft board application The signal transmission channel and the working bandwidth increase, and there are still problems such as thickening of the thickness, insufficient flexibility, and high characteristic impedance. Therefore, the traditional single-channel soft-board bridge is used in a double-layer soft board in applications with a small transmission rate. For the mainstream, it is unable to support the signal transmission of high-order video card bridges.

In addition, traditional single-channel or dual-channel hard-board bridges can be used to produce high-performance, high-density, and multi-layer interconnected boards with the maturity of board process technology, and to meet the needs of high-frequency signal transmission and electrical appliances. Characteristics, reduction of skin effect and electromagnetic interference between adjacent circuit layers, etc., must add more power and ground planes, the number of layers is representative of the number of layers with independent circuit layers, usually the number of layers are even (such as double , four layers, eight layers, etc.), but because the number of layers is more than thick, the flexibility is also poor and can not be bent. If it is applied to the dual-channel dual-channel bridging technology, it will also be manufactured by various manufacturers. The different design schemes of the motherboard or the display card make the bridge distance of the dual graphics card cannot be unified, so that the traditional dual-channel hard-board bridge cannot be bridged arbitrarily with the different spacing of the dual graphics cards, which is difficult to meet the user's own upgrade and expansion. Demand is the key to research and improvement for those in this industry.

Therefore, in view of the above-mentioned problems and shortcomings, the inventors have collected such relevant materials through various evaluations and considerations, and have used the trial and modification of many years of R&D experience in this industry to start such micro-thin two-channel flexible circuit bridging. The invention patent for the line was born.

The main purpose of the present invention is to sequentially include a first insulating layer, a first wiring layer, a second insulating layer, a ground layer, a third insulating layer, a second wiring layer, and a fourth insulating layer by using a dual-channel flexible circuit board. The invention has the advantages of thinning and higher flexural resistance between 0.2 and 0.6 mm, and is electrically connected to the first connection interface by the first circuit layer, the ground layer and the second circuit layer respectively. And the second connection interface, the first connection interface and the second connection interface can connect the two expansion interface cards of all the different spacings to form an arbitrary bridge state, and the ground layer between the first circuit layer and the second line is used as the dual channel High-frequency signals transmit a common reference plane, which not only meets the requirements of working bandwidth, but also meets the requirements of characteristic impedance for high-frequency signal integrity and reduces the skin effect of high-frequency signal reflection and transmission processes. The formation has the effect of shielding and isolation, so that the distance between the circuit layer and the reference plane is close, and the electromagnetic wave and crosstalk generated correspondingly during the transmission of the high-frequency signal can be reduced, thereby achieving stable two-channel high. Frequency signal transmission and the effect of improving transmission efficiency.

10‧‧‧Double-channel flexible circuit board

101‧‧‧First flexible substrate

102‧‧‧Second flexible substrate

103‧‧‧ Third soft substrate

11‧‧‧First insulation

111‧‧‧First film

112‧‧‧ first layer

12‧‧‧First line layer

121‧‧‧First conductor

13‧‧‧Second insulation

131‧‧‧Second film

132‧‧‧second second layer

133‧‧‧ third layer

14‧‧‧ Grounding layer

141‧‧‧Metal conductor

15‧‧‧ third insulation

151‧‧‧ Third film

152‧‧‧ fourth layer

153‧‧‧ fifth layer

16‧‧‧Second circuit layer

161‧‧‧second conductor

17‧‧‧fourth insulation

171‧‧‧fourth film

172‧‧‧ sixth layer

18‧‧‧through hole

20‧‧‧First connection interface

21‧‧‧First Bridge

211‧‧‧First socket

2111‧‧‧ Socket slot

212‧‧‧First terminal group

2121‧‧‧Docking Department

2122‧‧‧Welding Department

22‧‧‧First reinforcement board

221‧‧‧ jack

222‧‧‧ glue layer

30‧‧‧Second connection interface

31‧‧‧Second Bridge

311‧‧‧second socket

3111‧‧‧ Socket slot

312‧‧‧Second terminal group

3121‧‧‧Docking Department

3122‧‧‧Welding Department

32‧‧‧Second reinforcing plate

321‧‧‧ jack

322‧‧ ‧ glue layer

40‧‧‧System Host

41‧‧‧ motherboard

411‧‧‧ slots

42‧‧‧Expansion interface card

420‧‧‧ chipsets

421‧‧‧Transport interface

422‧‧‧Bridge end connector

4221‧‧‧Metal joints

43‧‧‧heating device

The first figure is a three-dimensional appearance of the present invention.

The second figure is a perspective exploded view of the present invention.

The third figure is a perspective exploded view of another perspective of the present invention.

The fourth figure is a schematic structural view of the two-channel flexible circuit board of the present invention.

Figure 5 is a schematic view showing the structure of a two-channel flexible circuit board according to a preferred embodiment of the present invention.

Figure 6 is a perspective view of a preferred embodiment of the present invention prior to joining.

Figure 7 is a perspective view of a preferred embodiment of the present invention after being joined.

Figure 8 is a perspective view of a further preferred embodiment of the present invention.

In order to achieve the above objects and effects, the technical means and constructions of the present invention will be described in detail with reference to the preferred embodiments of the present invention.

Please refer to the first, second, third, fourth and fifth figures, which are respectively a three-dimensional external view, an exploded perspective view, an exploded perspective view of another perspective, a schematic diagram of a two-channel flexible circuit board and a preferred implementation. For a schematic diagram of the structure of the dual-channel flexible circuit board, it can be clearly seen from the figure that the micro-thin double-channel flexible circuit bridge wiring of the present invention includes the dual-channel flexible circuit board 10 and the same plane disposed opposite to the dual-channel flexible circuit board 10. The first connection interface 20 and the second connection interface 30 are electrically connected at the side, wherein the dual-channel flexible circuit board 10 sequentially includes the first insulation layer 11, the first circuit layer 12, the second insulation layer 13, and the connection. The first insulating layer 11 has a first film 111, and a first bonding layer 112 is disposed on the upper surface of the first film 111 to form a ground layer 14, a third insulating layer 15, a second wiring layer 16, and a fourth insulating layer 17. a cover film, and the first conductive layer 121 of the first circuit layer 12 is bonded to the first film 111 through the first adhesive layer 112, and the lower surface of the second film 131 of the second insulating layer 13 is provided. Combined with the second on the first conductor 121 The layer 132 is disposed on the upper surface of the second film 131, and the third layer 133 is disposed between the first circuit layer 12 and the second circuit layer 16 and is provided by the ground layer 14. The conductor 141 is bonded to the second film 131 through the third adhesive layer 133. The lower surface of the third film 151 of the third insulating layer 15 is provided with a fourth adhesive layer 152 bonded to the metal conductor 141. The fifth film 151 is provided with a fifth adhesive layer 153 on the upper surface thereof, and the second conductive layer 161 of the second circuit layer 16 is bonded to the third film 151 through the fifth adhesive layer 153, and the fourth insulating layer 17 is provided. The lower surface of the fourth film 171 is provided with a sixth adhesive layer 172 to form another cover film, and is bonded to the second conductor 161 by the fourth film 171 through the sixth adhesive layer 172 to form a flexible multilayer board.

Furthermore, the first film 111 of the first insulating layer 11, the second film 131 of the second insulating layer 13, the third film 151 of the third insulating layer 15, and the fourth film 171 of the fourth insulating layer 17 comprise a polycrystalline film. Amine (PI), polyethylene terephthalate (PET) or other film material with insulation and flexibility, preferably made of polyimide film material, wherein the first film 111 The thickness of the fourth film 171 may be between 0.5 and 1 mil (1 mil = 0.0254 mm), preferably 25 μm (1 mm = 1000 μm), and the thickness of the second film 131 and the third film 151 may be Between 1 and 2 mils, preferably 50 μm.

The first adhesive layer 112 of the first insulating layer 11, the second adhesive layer 132 of the second insulating layer 13, and the third adhesive layer 133, the fourth adhesive layer 152 and the fifth adhesive layer 153 of the third insulating layer 15, The sixth adhesive layer 172 of the fourth insulating layer 17 is made of epoxy resin, polyester resin, acrylic resin or other thermosetting glue, wherein the first adhesive layer 112, The thickness of the fourth adhesive layer 152 and the sixth adhesive layer 172 may be between 20 and 30 μm, preferably 25 μm, and the thicknesses of the second adhesive layer 132, the third adhesive layer 133 and the fifth adhesive layer 153 may be respectively Between 15 and 25 μm, preferably 20 μm; in addition, the first conductor 121 of the first circuit layer 12 and the second conductor 161 of the second circuit layer 16 can be made of materials such as rolled copper foil or electrolytic copper foil. Preferably, the rolled copper foil has higher flexural resistance, and the desired wiring is formed by etching or the like, and the ground layer 14 is disposed between the first wiring layer 12 and the second wiring layer 16, and The metal conductor 141 of the ground layer 14 may be made of a metal material such as copper, aluminum or silver, preferably copper foil to form a metal foil film. Or the aspect of the woven mesh, and the thickness of the first circuit layer 12, the ground layer 14, and the second circuit layer 16 may be between 30 and 40 μm, preferably 35 μm, and the ground layer 14 may be adjacent to The first and second circuit layers 12 and the second circuit layer 16 transmit a common reference plane or a ground plane (0V reference plane).

In the present embodiment, the dual-channel flexible circuit board 10 includes a first insulating layer 11, a first wiring layer 12, a second insulating layer 13, a ground layer 14, a third insulating layer 15, a second wiring layer 16, and a fourth. The insulating layer 17 may further include a first flexible substrate 101, a second flexible substrate 102, and a third flexible substrate 103. The first flexible substrate 101 is formed by the first film 111 of the first insulating layer 11 and the first adhesive layer 112. The first conductor 121 of the first circuit layer 12 is formed into a flexible copper foil substrate (3 Layer FCCL), and the desired wiring is formed by etching or the like. Similarly, the second flexible substrate 102 is composed of The second film 131 of the second insulating layer 13, the third bonding layer 133 and the metal conductor 141 of the ground layer 14 are formed into a gel-like flexible copper foil substrate, and the third flexible substrate 103 is composed of the fourth insulating layer 17 The fourth film 171, the sixth back layer 172 and the second conductor 161 of the second circuit layer 16 are combined to form a glue-based flexible copper foil substrate, and the dual-channel flexible circuit board 10 or the first flexible substrate 101, the second softness The total thickness of the substrate 102 plus the third flexible substrate 103 can be between 0.2 and 0.6 mm, and Two groups of plurality of via holes 18 are respectively disposed at two sides of the flexible circuit board 10, and each of the via holes 18 is electrically connected to the first circuit layer 12, the ground layer 14 and the second circuit layer 16, respectively, to realize multiple layers. Interlayer interconnection of structures.

The first connection interface 20 includes at least two first bridges 21 having a first socket 211, and the first terminal group 212 is oppositely disposed on the two side wall surfaces of the two sockets 211. A plurality of butting portions 2121 are suspended, and each of the abutting portions 2121 is respectively provided with a welded portion 2122 which is disposed to be displaced from the bottom of the first socket 211 with respect to the other side of the upper opening of the insertion slot 2111, and is configured to form a plug-in type. Or the first bridge 21 of the dual in-line package (DIP) type, and the first reinforcement board with the plurality of sockets 221 is respectively disposed below the first socket 211 of the first bridge 21 22, and the insertion holes 221 are respectively disposed corresponding to the soldering portions 2122 at the lower portion of the first terminal group 212, and a bonding layer 222 is disposed on the surface of the first reinforcing plate 22 (as shown in the fourth figure).

The second connection interface 30 includes at least two second bridges 31 having a second socket 311, and the second terminal group 312 is opposite to the two side walls of the two sockets 311. The plurality of abutting portions 3121 are suspended, and each of the abutting portions 3121 is respectively provided with a welded portion 3122 that is disposed to be displaced from the bottom of the second socket 311 to form a misaligned portion with respect to the other side of the upper opening of the insertion slot 3111. Or a second bridge 31 of a dual in-line package (DIP) type, and a second reinforcing plate with a plurality of jacks 321 respectively disposed under the second socket 311 of the second bridge 31 32, and the jacks 321 are respectively disposed corresponding to the soldering portions 3122 at the lower portion of the second terminal group 312, and the surface of the second reinforcing plate 32 is provided with a bonding layer 322 (as shown in the fourth figure).

However, the first reinforcing plate 22 of the first connecting interface 20 and the second reinforcing plate 32 of the second connecting interface 30 may respectively be a fiberglass board, a steel sheet, a polypropylene (PP), a polyphenylene dioxide of a flame resistant material grade FR4. Made of ethylene glycol formate (PET), ceramic or other metal or non-metal (such as inorganic or organic insulating materials), preferably FR4 fiberglass board, and the thickness of the first reinforcing plate 22 and the second reinforcing plate 32 The glue layers 222 and 322 which are coated or bonded on the surfaces of the first reinforcing plate 22 and the second reinforcing plate 32 respectively may be double-sided adhesive tape, hot melt adhesive, Epoxy resin, polyester resin, acrylic resin and other adhesive paper or pressure sensitive adhesive, preferably double-sided adhesive tape, and the thickness of the glue layer 222, 322 depends on the first reinforcing plate 22 and the second reinforcing plate 32 The material selected may be between 0.005 and 0.20 mm, preferably 50 μm.

When the present invention is assembled, the body of the dual-channel flexible circuit board 10 that completes the processing (such as inner layer fabrication, copper foil etching molding circuit, pressing, drilling, and plating to form metallized holes, etc.) is first punched out to a specific The first bridge 21 of the first connection interface 20 and the second bridge 31 of the second connection interface 30 are respectively disposed on two sides of the same plane of the dual-channel flexible circuit board 10, The soldering portion 2122 of the one terminal group 212 and the soldering portion 3122 of the second terminal group 312 respectively penetrate vertically downward into the corresponding via holes 18 at the two sides of the dual-channel flexible circuit board 10, and the plurality of first sockets 211 The bottom of the second socket 311 is formed on the same plane as the two-channel flexible circuit board 10, and is disposed at a distance from the bottom of the two-channel flexible circuit board 10 to the left and right, and is formed by using a through hole welding through the two-channel flexible circuit board 10. The connection is made, and the solder structure on the first terminal group 212, the second terminal group 312 and the two-channel flexible circuit board 10 is effectively prevented from being damaged or peeled off, so that the overall structure is more stable.

The flux used on the soldering portion of the via hole 18 of the dual-channel flexible circuit board 10 is continuously removed, and the double-channel flexible circuit board 10 is sized on the other side surface of the first bridge 21 and the second bridge 31. Or, the release film attached to the first reinforcing plate 22 and the second reinforcing plate 32 on the bonding layers 222 and 322 is peeled off, and each of the insertion holes 221 and 321 respectively corresponds to the first terminal group 212 and the second terminal. The terminal group 312 passes through the soldering portions 2122 and 3122 on the back surface of the dual-channel flexible circuit board 10, and then presses the first reinforcing plate 22 and the second reinforcing plate 32 respectively, so as to be coupled to the dual channel through the bonding layers 222 and 322. On the back surface of the flexible circuit board 10, the plurality of sockets 221 and 321 of the first and second reinforcing plates 22 and 221 are larger than the plurality of soldering portions 2122 and 3122 of the first terminal group 212 and the second terminal group 312. A reinforcing plate 22 and a second reinforcing plate 32 can be reinforced and pressed against the back surface of the dual-channel flexible circuit board 10 to prevent air bubbles from being formed to ensure the mutual characteristics of each other, thereby completing the assembly of the present invention as a whole.

As shown in the fifth figure, the two-channel flexible circuit board 10 in this embodiment is different from the above embodiment in that the first film 111 of the first flexible substrate 101 and the first conductor 121 may not be used first. The layer 112 and the first conductor 121 of the first circuit layer 12 can be directly formed on the first film 111 according to the process to form a non-glue flexible copper foil substrate (2 Layer FCCL), and then formed by etching or the like. The required circuit, but not limited thereto, the third adhesive layer 133 disposed between the second film 131 of the second flexible substrate 102 and the metal conductor 141, and the third flexible substrate 103 The sixth bonding layer 172 disposed between the fourth film 171 and the second conductor 161 may also be omitted, and the metal conductor 141 and the second conductor 161 may be directly formed on the second film 131 and the fourth film 171 according to different processes. The gel-free flexible copper foil substrate and the gel-free flexible copper foil substrate are mainly different from each other in the first flexible substrate 101, the second flexible substrate 102, and the third flexible substrate 103. Between film and copper foil In the adhesive layer, problems such as internal stress and thinning of the metal can be avoided in the adhesive layer, and the flexibility and the dimensional stability are good, and the total thickness of the overall structure can be reduced in the case where the number of layers is reduced. However, the process of the non-adhesive soft copper foil substrate (such as coating method, pressing method, sputtering/electroplating method, etc.) is relatively expensive, and in contrast, the adhesive soft copper foil substrate is obtained by passing the film and the copper foil through the subsequent lamination. Compared with the non-adhesive soft copper foil substrate, it has the advantage of lower cost, but is more suitable for thicker copper layer fabrication, and can meet the required thickness, flexural resistance, etc. of the dual-channel flexible circuit board 10. The characteristics are different in the production method, so they are explained together in the contents of the following description of the case, and are combined with Chen Ming.

Please refer to the sixth, seventh and eighth figures, which are respectively a perspective view of a preferred embodiment of the present invention, a three-dimensional appearance after the connection, and a three-dimensional appearance of a further preferred embodiment. As can be clearly seen from the figure, the system host 40 to which the micro-dual flexible circuit bridge wiring of the present invention can be applied includes, but is not limited to, a desktop or personal computer, an industrial computer, a server, a barebone system, etc., and the system host 40 includes The motherboard 41 is provided with a plurality of slots 411 arranged side by side on the motherboard 41. For example, the computer bus is interconnected based on the existing peripheral component interconnection (PCI) standard (PCI Express, PCI for short). -E or PCIe) standard, and at least two slots 411 are respectively connected with a transmission interface 421 of the expansion interface card 42, for example, a Graphics Card capable of supporting SLI technology, but actually The application is not limited to this, and it can also be an expansion card of PCI-E to USB/SATA/eSATA/RS-232 interface, a network card of PCI-E interface or a sound card, and the expansion interface card 42 On the surface, there are image processing units (GPUs) and network chips. The chip set 420 of the audio chip or the like, the expansion interface card 42 in the embodiment is a display card capable of supporting SLI technology, and two front and rear intervals are respectively disposed at the top edge of each expansion interface card 42 near the side edge. A bridge connector 422 is provided at a distance, and a plurality of metal contacts 4221 are respectively disposed on the left and right sides of the bridge connector 422. The expansion interface card 42 cooperates with the motherboard 41 to perform functions such as 3D picture calculation and graphics acceleration.

When the micro-thin flexible flexible circuit bridge of the present invention is to be connected to the two expansion interface cards 42 on the motherboard 41, the two-channel flexible circuit board 10 in the first figure is first turned over at 180 degrees. The direction of the first connection interface 20 and the second connection interface 30 respectively correspond to the two expansion interface cards 42 respectively, and the first bridge 21 can be respectively downwardly docked to the corresponding one of the first expansion interface cards 42. The end joint 422 is bridged, and the bridge end joint 422 is inserted into the insertion slot 2111 of the first socket 211, and the first terminal set 212 is pushed outwardly relative to the abutting portion 2121. The terminal connector 422 can be smoothly inserted into the insertion slot 2111, and the abutting portion 2121 of the first terminal group 212 abuts the corresponding plurality of metal contacts 4221 on the bridge terminal connector 422 to form a positive electrical connection. The second socket 311 of the second bridge 31 is respectively connected to the bridge terminal 422 of the second expansion interface card 42 in the manner described above, and the butting portion 2121 of the second terminal group 312 is brought into contact with the bridge terminal 422. The corresponding complex metal contact 4221 The first connection interface 20 with the two first bridges 21 and the second bridge 31 on the two sides of the dual-channel flexible circuit board 10 and the second connection interface 30 are connected to the second connection interface 30. The four bridge terminals 422 of the interface card 42 are expanded to form a two-channel bridge state between the two expansion interface cards 42 so that the system host 40 can perform parallel calculation using the chip sets 420 on the two expansion interface cards 42. Improve the performance of faster computing and graphics display.

In this embodiment, when the two-channel flexible circuit board 10 is connected to the second connection interface 32 by using the first connection interface 20 and the second connection interface 30, the first bridge 21 and the second bridge 31 are connected to form two expansion interface cards 42. In the bridge state, the two-channel high-frequency signal transmission can be provided by the first circuit layer 12 and the second circuit layer 16, and the ground layer 14 between the first circuit layer 12 and the second circuit layer 16 is used as a high-frequency signal transmission. The reference plane matches the impedance of the first circuit layer 12 and the second circuit layer 16 with the ground layer 14 to meet the requirement of a characteristic impedance of 50 ohms (Ω), and can reduce the generation of skin during high-frequency signal reflection and transmission. The effect of the power loss, while the first circuit layer 12 and the second circuit layer 16 are shielded and isolated by the ground layer 14, so that the distance between the circuit layer and the reference plane is close to reduce the corresponding generation of high-frequency signal transmission. The interference of electromagnetic waves and crosstalk, the multi-layer flexible circuit board 10 multi-layer structure design, compared with the traditional single-channel soft-board bridge wiring, the working bandwidth is only 400MHz or the traditional dual-channel hard-board bridge has a working bandwidth of only 680MHz. The problem that the working bandwidth is increased cannot be satisfied, and there are still problems such as thickening of the thickness and insufficient flexibility of the signal transmission channel and the working bandwidth. The dual-channel flexible circuit board 10 of the present invention can not only meet the working frequency. The width is increased to 1360MHz, and the total thickness is between 0.2 and 0.6mm to achieve thinning and higher flexural resistance. For high-frequency signal transmission integrity, the characteristic impedance is still 50. Ohmic (Ω) test requirements, in order to achieve stable dual-channel high-frequency signal transmission and improve transmission efficiency.

In addition, the dual-channel flexible circuit board 10 used in the present invention has light weight, higher flex resistance and thinning characteristics, and can bend the double-channel flexible circuit board 10 to form upward arching, sagging or The folding forms an acute angle setting, and the plurality of flexing does not cause the destruction or breakage of the structure of the two-channel hard board bridge, so that the first connection interface 20 and the second connection interface 30 can be the first of the two pairs. The bridge 21 and the second bridge 31 connect the two expansion interface cards 42 of different pitches to suit different designs of the motherboard 41 or the expansion interface card 42 manufactured by various manufacturers, and are not subject to different bridge distances. Or the space limit is limited to meet the user's own upgrade and expansion requirements.

As shown in the eighth embodiment, the system host 40 in this embodiment differs from the above embodiment in that the expansion interface card 42 further includes a heat sink 43 and has a heat sink 43 against the surface of the wafer set 420. The heat dissipation module (such as a heat sink or a plurality of heat sinks of the heat sink), and the fan is mounted on the heat dissipation module or can be further provided with a plurality of heat pipes to connect the power cable of the fan to the expansion interface card 42 The fan is operated to match the heat dissipation module to assist the chip set 420 to dissipate heat rapidly.

Since the expansion interface card 42 is generally provided with a heat sink 43 on the expansion interface card 42 for the purpose of rapid heat dissipation, the size of the expansion interface card 42 in the width direction is increased, and any two adjacent slots 411 are added. In the case that the expansion interface card 42 cannot be separately inserted, two slots 411 need to be vacant between the two expansion interface cards 42 to form an architecture spanning the four slots 411, and then the dual-channel flexible circuit board 10 is utilized. The first bridge 21 and the second bridge 31 of the connection interface 20 and the second connection interface 30 are connected between the two expansion interface cards 42, and can be applied not only to the motherboard 41 and the expansion of different specifications. The interface card 42 can eliminate the need to install different specifications of the dual-channel hard-board bridge due to the difference between the two expansion interface cards 42, and the utility model has the advantages of increased use cost and inconvenient storage when not in use, and is more practical and applicable. The effect.

Therefore, the present invention is mainly directed to the use of the dual-channel flexible circuit board 10 to sequentially include the first insulating layer 11, the first wiring layer 12, the second insulating layer 13, the ground layer 14, the third insulating layer 15, and the second circuit layer. 16 and the fourth insulating layer 17 have a thickness of 0.2 to 0.6 mm and a thinning and higher flexural resistance, and are electrically connected by the first connection of the two sides of the dual-channel flexible circuit board 10 The interface card 20 and the second connection interface 30 are connected to the two expansion interface cards 42 of different pitches to form a bridge state, and the ground layer 14 between the first circuit layer 12 and the second circuit layer 16 can be used as a dual channel high frequency signal transmission. The reference plane not only satisfies the requirements of working bandwidth and characteristic impedance, but also makes the distance between the circuit layer and the reference plane close, which can reduce electromagnetic interference during high-frequency signal transmission, thereby achieving stable two-channel high-frequency signal transmission and improved transmission. The effect of efficiency.

The detailed description of the present invention is intended to be a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and other equivalents and modifications may be made without departing from the spirit of the invention. Changes are intended to be included in the scope of the patents covered by the present invention.

In summary, the above-mentioned micro-thin double-channel flexible circuit bridge wiring of the present invention can achieve its efficacy and purpose when used. Therefore, the invention is an invention with excellent practicability, and is in fact conforming to the application requirements of the invention patent, and is proposed according to law. To apply, I hope that the trial committee will grant this case as soon as possible to protect the inventor's hard work. If there is any doubt in the bureau, please do not hesitate to give instructions, the inventor will try his best to cooperate, and feel really good.

Claims (10)

 A micro-thin dual-channel flexible circuit bridge connection includes a dual-channel flexible circuit board and a first connection interface and a second connection interface formed on the two sides of the dual-channel flexible circuit board to form an electrical connection, wherein: the double The channel flexible circuit board sequentially includes a first insulating layer, a first circuit layer, a second insulating layer, a ground layer, a third insulating layer, a second circuit layer and a fourth insulating layer, the first The circuit layer, the ground layer, and the second side of the second circuit layer are electrically connected to the first connection interface and the second connection interface, respectively, the ground layer is disposed between the first circuit layer and the second circuit layer Used to transmit a common reference plane as a two-channel signal, whereby the first circuit layer and the second circuit layer match the impedance of the ground layer.    The micro-thin double-channel flexible circuit bridge of claim 1, wherein the first insulating layer has a first film; the first circuit layer has a first conductor; and the second insulating layer has a second a film, a lower surface of the second film is provided with a second adhesive layer bonded to the first conductor; the ground layer has a metal conductor; the third insulating layer has a third film, and the lower surface of the third film is provided a fourth bonding layer bonded to the metal conductor, the third film is provided with a fifth bonding layer on the upper surface thereof; the second wiring layer has a second bonding layer bonded to the third film through the second bonding layer The fourth insulating layer has a fourth film; the first film and the fourth film have a thickness of between 0.5 and 1 mil, respectively; and the second film and the third film have a thickness of 1 Between 2 mils; the thickness of the second adhesive layer and the fifth adhesive layer is between 15 and 25 μm; the thickness of the fourth adhesive layer is between 20 and 30 μm; the first conductor, the first conductor The thickness of the ground layer and the second conductor are between 30 and 40 μm, respectively.    The micro-thin flexible circuit bridge of claim 2, wherein the dual-channel flexible circuit board has a first flexible substrate, a second flexible substrate, and a third flexible substrate on the first film. a first adhesive layer is disposed on the surface, and the first conductive system is bonded to the first film through the first adhesive layer, wherein the first flexible substrate is composed of the first film, the first adhesive layer and the first conductive layer Forming a rubber-based flexible copper foil substrate; the upper surface of the second film is provided with a third adhesive layer, the metal conductive system is bonded to the second film through the third adhesive layer, and the second flexible substrate is composed of the second The film, the third adhesive layer and the metal conductor are formed with a rubber-based flexible copper foil substrate; the fourth film is provided with a sixth adhesive layer on the lower surface thereof, and the fourth film is bonded to the second through the sixth adhesive layer In the conductor, the third flexible substrate comprises a fourth flexible film, the sixth adhesive layer and the second conductive conductor; and the thickness of the first adhesive layer and the sixth adhesive layer are respectively Between 20~30μm; Then three layer thickness is between 15 ~ 25μm.    The micro-thin two-channel flexible circuit bridge connection according to claim 3, wherein the first adhesive layer, the third adhesive layer and the sixth adhesive layer comprise an epoxy resin, a polyester resin or an acrylic resin production.    The micro-thin flexible circuit bridge of claim 2, wherein the dual-channel flexible circuit board has a first flexible substrate, a second flexible substrate, and a third flexible substrate, the first flexible substrate The first circuit layer is formed on the first film to form a gel-free flexible copper foil substrate; the second flexible substrate is formed on the second film by the metal conductor to form a gel-free soft copper foil substrate. The third flexible substrate is formed on the fourth film from the second conductor to form a gel-free flexible copper foil substrate.    The micro-thin two-channel flexible circuit bridge connection according to claim 2, wherein the first film, the second film, the third film and the fourth film comprise polyimide or poly(ethylene terephthalate) Made of a film of an alcohol ester.    The micro-thin two-channel flexible circuit bridge connection according to claim 2, wherein the second adhesive layer, the fourth adhesive layer and the fifth adhesive layer comprise an epoxy resin, a polyester resin or an acrylic resin production.    The micro-thin two-channel flexible circuit bridge connection according to claim 2, wherein the first conductor and the second conductor are respectively a rolled copper foil or an electrolytic copper foil, and the circuit is formed through an etching process.    The micro-thin two-channel flexible circuit bridge connection according to claim 2, wherein the metal conductor is made of copper, aluminum or silver.    The micro-thin flexible circuit bridge connection according to claim 1, wherein the dual-channel flexible circuit board has a thickness of between 0.2 and 0.6 mm.