CN106028645A - High-speed hard-soft combining plate with soft areas of different lengths and manufacturing method thereof - Google Patents

Abstract

The invention discloses a high-speed hard-soft combining plate with soft areas of different lengths and a manufacturing method thereof. Soft plates of different layers are designed into structures with bending areas, of which the lengths are gradient. When soft areas are bent, pulling and extruding may not occur to ensure same interlayer gaps and further eliminate severe influence on impedance due to change of a referential plane. Signal integrity of the hard-soft combining plate is improved.

Description

A kind of soft zone Length discrepancy high speed Rigid Flex and preparation method thereof

Technical field

The present invention relates to Rigid Flex field, particularly relate to a kind of soft zone Length discrepancy high speed Rigid Flex and making thereof Method.

Background technology

Rigid Flex than ordinary circuit board gentlier, more save space.Rigid Flex is used in the application such as Aero-Space It it is very good solution.The motility of this circuit board is embodied in it and can fold, bends, squeeze into the least sky Between.It is suitable for any equipment, it is possible to improve the ability of product miniaturization.Rigid Flex also can reduce being manufactured into of equipment This, because its volume is little so the size of packaging can be reduced, thus reduce the material cost needed for producing.Additionally, soft or hard combines The flexible circuit of plate decreases the demand of interconnection wiring and solder connector.Make whole system circuit relatively reliable, resistance to With.Rigid Flex is flexible PCB plate with hard circuit board after pressing working procedure, by related process requirements combination one Rise.Hardboard is conventional rigid printed circuit plate, and adagio is that polyimides (PI) flexible substrate two sides is covered with after Copper Foil again at Copper Foil The coverlay being made up of PI material and adhesive glue is sticked on layer.The rigid region of Rigid Flex has the highly reliable of rigid plate Property, flexible region has the bendable folding endurance of flexible board and three-dimensional installation.Rigid Flex has been widely used in consumption electricity In the products such as son, communication, Industry Control and defence and military.In recent years, along with chip clock frequency reach hundreds of MHz or even GHz, data rate reaches more than Gbps, the rise/fall of corresponding pulse signal along more precipitous, pulsewidth up to ps magnitude, Interconnection line on PCB starts gradually to present " transmission line " effect, has been not to be regarded as simple connecting line, inevitably to signal Transmission line proposes the requirement of impedance matching.Impedance control requirement is there is in the case of high-frequency signal.

Design currently for the Rigid Flex under high frequency situations, hard area and soft zone separate computations impedance, respectively according to hard Property region and flexible region lamination calculate meet the live width of resistance requirements, distance between centers of tracks, soft or hard transitional region implement modified line width, Become the mode of spacing.Although this mode ensure that rigid and flexible region impedance matching, but and does not takes into account flexible region The impact that during bending, between soft board monolithic, the change in gap brings.Owing to the application scenario of Rigid Flex usually bends installation Or dynamic bending, bending can cause the impedance mismatch of flexible region, and the impact on signal transmission performance is bigger.Relative to For common hardboard, there is certain gap between each soft board monolithic in the Rigid Flex comprising multiple flexible monolithic, therefore The signal line impedance of soft zone is according to interlayer spacings when not bending and Structure Calculation, and generally micro-strip line impedance calculates mould Formula.But when soft board bends to same direction, if each soft board monolithic length is equal, due to thickness of slab and interlayer spacings because of Element, the crooked process radius of different soft boards is different, causes outermost layer soft board to be stretched, and innermost layer soft board is squeezed, this stretching Soft board depression can be caused to swell even internal layer soft board with extruding tightly to fit outer layer adagio, as it is shown in figure 1, it is flexible single to comprise multiple Causing reference plane to change after the Rigid Flex bending of sheet, situation about tightly fitting from microstrip line patten transformation is especially Strip line pattern, therefore bending inevitably results in the impedance of flexible region and does not mates.

Summary of the invention

It is an object of the invention to by a kind of soft zone Length discrepancy high speed Rigid Flex and preparation method thereof, solve with The problem that upper background section is mentioned.

For reaching this purpose, the present invention by the following technical solutions:

A kind of soft zone Length discrepancy high speed Rigid Flex, it is characterised in that include Rigid Flex body；Described soft or hard is tied In plywood body there is length gradient in the bending region of different layers soft board.

The invention also discloses the manufacture method of a kind of soft zone Length discrepancy high speed Rigid Flex, it comprises the steps:

S101, determine PCB (printed circuit board) number of plies, thickness of slab, soft or hard district base material, stacked relationship and impedance desired control Value；

S102, determine soft or hard region layer stacked structure and each connect up parameter；

S103, according to layer stack stack structure and wiring parameter constraint is set, carry out layout design；

S104, determine overbending direction and bending angle according to the concrete installation requirements of soft board；

S105, determine benchmark soft board length according to soft board overbending direction；

S106, thick, between coverlay thickness and hard area soft board monolithic according to bending angle, flexible board substrate thickness, copper Prepreg thickness calculates each layer soft board length successively, obtains Length discrepancy processing request；

S107, PCB domain design completed are processed according to Length discrepancy processing request, enter the PCB machined Row testing impedance is verified.

Especially, described step S106 specifically includes: assume that equivalence crooked process radius is the length to each layer of centrage, etc. The length of the effect a length of each layer of centrage of soft board；If soft board A, B, C a length of La, Lb, Lc centrage, coverlay thickness is CL, individual soft board thickness is T, and between soft board monolithic, PP sheet thickness is P, and bending angle is θ, wherein, T=PI core thickness+2 × Thick+2 × CL of copper, adagio on the basis of the shortest inner side soft board C, soft board B, A length lengthens successively, and concrete reckoning process is as follows:

Basic arc length L₀:

$L_0=2{\mathrm{\πr}}_0\frac{\mathrm{\θ}}{2\mathrm{\π}}=r_0\mathrm{\θ}$

Soft board C effective radius r_c:

$r_c=r_0+\frac{T}{2}$

Soft board C effective length L_c:

L_c=r_cθ

Soft board B effective radius r_b:

r_b=r_c+[T+(P-2*CL)]

Soft board B effective length L_b:

L_b=r_bθ={ r_c+ [T+ (P-2*CL)] } * θ=L_c+[T+(P-2*CL)]*θ

Soft board A effective radius r_a:

r_a=r_c+2*[T+(P-2*CL)]

Soft board A effective length L_a:

L_a=r_aθ={ r_c+ 2* [T+ (P-2*CL)] } * θ=L_c+2*[T+(P-2*CL)]*θ

Therefore, by that analogy, if software board has n to open soft board, then soft board length L_nFor

L_n=L_c+(n-1)*[T+(P-2*CL)]*θ

The most any one layer of soft board with the length difference of datum layer soft board is

Δ L=(n-1) * [T+ (P-2*CL)] * θ.

Different layers soft board is designed embayment by soft zone Length discrepancy high speed Rigid Flex that the present invention proposes and preparation method thereof There is the structure of length gradient in territory, folding area, does not haves when soft zone bends and pulls and extruding situation, it is ensured that interlayer spacings is not Become, thus eliminate because impedance is had a strong impact on by reference plane change, improve the signal integrity of Rigid Flex.

Accompanying drawing explanation

Fig. 1 is structural representation after the Rigid Flex bending comprising multiple flexible monolithic；

Schematic diagram before the soft zone Length discrepancy high speed Rigid Flex bending that Fig. 2 provides for the embodiment of the present invention；

Schematic diagram after the soft zone Length discrepancy high speed Rigid Flex bending that Fig. 3 provides for the embodiment of the present invention；

The soft zone Length discrepancy high speed Rigid Flex manufacture method flow chart that Fig. 4 provides for the embodiment of the present invention.

Detailed description of the invention

For the ease of understanding the present invention, below with reference to relevant drawings, the present invention is described more fully.In accompanying drawing Give presently preferred embodiments of the present invention.But, the present invention can realize in many different forms, however it is not limited to institute herein The embodiment described.On the contrary, provide the purpose of these embodiments be make to the disclosure understand more thorough Comprehensively.It should be noted that unless otherwise defined, all of technology used herein and scientific terminology with belong to the present invention's The implication that those skilled in the art are generally understood that is identical.The term used the most in the description of the invention is simply In order to describe the purpose of specific embodiment, it is not intended that in limiting the present invention.

In the present embodiment, soft zone Length discrepancy high speed Rigid Flex specifically includes Rigid Flex body；Described soft or hard combines In plate body there is length gradient in the bending region of different layers soft board.As in figure 2 it is shown, Fig. 2 for the embodiment of the present invention provide soft Schematic diagram before district's Length discrepancy high speed Rigid Flex bending, A in figure, B, C represent soft board A, soft board B, soft board C respectively.Such as Fig. 3 institute Show, schematic diagram after the soft zone Length discrepancy high speed Rigid Flex bending that Fig. 3 provides for the embodiment of the present invention.

As shown in Figure 4, the soft zone Length discrepancy high speed Rigid Flex manufacture method flow process that Fig. 4 provides for the embodiment of the present invention Figure.

In the present embodiment, the manufacture method of soft zone Length discrepancy high speed Rigid Flex specifically includes following steps:

S101, determine PCB layer number, thickness of slab, soft or hard district base material, stacked relationship and impedance desired control value.

S102, utilize impedance computation software to assist, determine soft or hard region layer stacked structure and each connect up parameter.

S103, utilize PCB design software, constraint is set according to layer stack stack structure and wiring parameter, carries out layout design.

S104, determine overbending direction and bending angle according to the concrete installation requirements of soft board.

S105, determine benchmark soft board length according to soft board overbending direction.

S106, thick, between coverlay thickness and hard area soft board monolithic according to bending angle, flexible board substrate thickness, copper Prepreg thickness calculates each layer soft board length successively, obtains Length discrepancy processing request.

Concrete, it is assumed that equivalence crooked process radius is the length to each layer of centrage, in the equivalence a length of each layer of soft board The length of heart line；As a example by Rigid Flex shown in Fig. 2, if soft board A, B, C a length of La, Lb, Lc centrage, coverlay thickness For CL, individual soft board thickness is T, and between soft board monolithic, PP sheet thickness is P, and bending angle is θ, wherein, and T=PI core thickness+2 Thick+2 × CL, the PI core thickness of × copper refers to the thickness of the medium of individual soft board own, adagio on the basis of the shortest inner side soft board C, Soft board B, A length lengthens successively, and concrete reckoning process is as follows:

Basic arc length L₀:

$L_0=2{\mathrm{\πr}}_0\frac{\mathrm{\θ}}{2\mathrm{\π}}=r_0\mathrm{\θ}$

Soft board C effective radius r_c:

$r_c=r_0+\frac{T}{2}$

Soft board C effective length L_c:

L_c=r_cθ

Soft board B effective radius r_b:

r_b=r_c+[T+(P-2*CL)]

Soft board B effective length L_b:

L_b=r_bθ={ r_c+ [T+ (P-2*CL)] } * θ=L_c+[T+(P-2*CL)]*θ

Soft board A effective radius r_a:

r_a=r_c+2*[T+(P-2*CL)]

Soft board A effective length L_a:

L_a=r_aθ={ r_c+ 2* [T+ (P-2*CL)] } * θ=L_c+2*[T+(P-2*CL)]*θ

Therefore, by that analogy, if software board has n to open soft board, then soft board length L_nFor

L_n=L_c+(n-1)*[T+(P-2*CL)]*θ

The most any one layer of soft board with the length difference of datum layer soft board is

Δ L=(n-1) * [T+ (P-2*CL)] * θ.

S107, PCB domain design completed are processed according to Length discrepancy processing request, enter the PCB machined Row testing impedance is verified.

Different layers soft board is designed to bend region by technical scheme the structure of length gradient, bends in soft zone Time do not have and pull and extruding situation, it is ensured that interlayer spacings is constant, thus eliminates because reference plane change impedance Have a strong impact on, improve the signal integrity of Rigid Flex.

One of ordinary skill in the art will appreciate that all or part of flow process realizing in above-described embodiment method, be permissible Instructing relevant hardware by computer program to complete, described program can be stored in a computer read/write memory medium In, this program is upon execution, it may include such as the flow process of the embodiment of above-mentioned each method.Wherein, described storage medium can be magnetic Dish, CD, read-only store-memory body (Read-Only Memory, ROM) or random store-memory body (Random Access Memory, RAM) etc..

Note, above are only presently preferred embodiments of the present invention and institute's application technology principle.It will be appreciated by those skilled in the art that The invention is not restricted to specific embodiment described here, can carry out for a person skilled in the art various obvious change, Readjust and substitute without departing from protection scope of the present invention.Therefore, although by above example, the present invention is carried out It is described in further detail, but the present invention is not limited only to above example, without departing from the inventive concept, also Other Equivalent embodiments more can be included, and the scope of the present invention is determined by scope of the appended claims.

Claims (3)

1. a soft zone Length discrepancy high speed Rigid Flex, it is characterised in that include Rigid Flex body；Described soft or hard combines In plate body there is length gradient in the bending region of different layers soft board.

2. the manufacture method of the soft zone Length discrepancy high speed Rigid Flex described in a claim 1, it is characterised in that include as Lower step:

S101, determine PCB layer number, thickness of slab, soft or hard district base material, stacked relationship and impedance desired control value；

S102, determine soft or hard region layer stacked structure and each connect up parameter；

S103, according to layer stack stack structure and wiring parameter constraint is set, carry out layout design；

S104, determine overbending direction and bending angle according to the concrete installation requirements of soft board；

S105, determine benchmark soft board length according to soft board overbending direction；

S106, half solid coverlay thickness and hard area soft board monolithic between thick according to bending angle, flexible board substrate thickness, copper Change sheet thickness and calculate each layer soft board length successively, obtain Length discrepancy processing request；

S107, PCB domain design completed are processed according to Length discrepancy processing request, hinder the PCB machined Anti-test checking.

The manufacture method of soft zone Length discrepancy high speed Rigid Flex the most according to claim 1, it is characterised in that described step Rapid S106 specifically includes: assume that equivalence crooked process radius is the length to each layer of centrage, in the equivalence a length of each layer of soft board The length of heart line；If soft board A, B, C a length of La, Lb, Lc centrage, coverlay thickness is CL, and individual soft board thickness is T, soft Between plate monolithic, PP sheet thickness is P, and bending angle is θ, and wherein, thick+2 × CL of T=PI core thickness+2 × copper, in the shortest Adagio on the basis of the soft board C of side, soft board B, A length lengthens successively, and concrete reckoning process is as follows:

Basic arc length L₀:

$L_0=2{\mathrm{\πr}}_0\frac{\mathrm{\θ}}{2\mathrm{\π}}=r_0\mathrm{\θ}$

Soft board C effective radius r_c:

$r_c=r_0+\frac{T}{2}$

Soft board C effective length L_c:

L_c=r_cθ

Soft board B effective radius r_b:

r_b=r_c+[T+(P-2*CL)]

Soft board B effective length L_b:

L_b=r_bθ={ r_c+ [T+ (P-2*CL)] } * θ=L_c+[T+(P-2*CL)]*θ

Soft board A effective radius r_a:

r_a=r_c+2*[T+(P-2*CL)]

Soft board A effective length L_a:

L_a=r_aθ={ r_c+ 2* [T+ (P-2*CL)] } * θ=L_c+ 2* [T+ (P-2*CL)] * θ therefore, by that analogy, if software combine Plate has n to open soft board, then soft board length L_nFor

L_n=L_c+(n-1)*[T+(P-2*CL)]*θ

The most any one layer of soft board with the length difference of datum layer soft board is

Δ L=(n-1) * [T+ (P-2*CL)] * θ.