The modeling method and system of printed circuit board
Technical field
The present invention relates to the modeling method and system of printed circuit board, it particularly relates to which a kind of full immersion liquid is cold
The modeling method and system of printed circuit board under environment.
Background technology
Liquid refrigeration technique is the change technology of Future Data center refrigeration modes, its social benefit and is reducing enterprise's fortune
There is the advantage of highly significant in terms of battalion's cost.So-called liquid is cold, refers to by certain liquid, for example, water, fluorination liquid or certain
Special nonconducting oil, it is to substitute air, the devices such as CPU, memory bar, chipset, expansion card is operationally caused
Heat is taken away.The cold working method of full immersion liquid is that device even complete machine is immersed directly in liquid, then passes through liquid
Circulation leads out heat, completely without fan.
Under the background that the subversiveness such as cloud computing, big data technology and theory are grown rapidly, PCB industries receive preceding institute not
Some impacts.High frequency, High-Speed PCB are widely used.It is different from tradition and more stresses PCB thermal reliability energy, now more
PCB product more emphatically consider be PCB SI (signal integrity) performance.
One complete pcb board material includes glass-fiber-fabric, resin and copper foil, and these three materials have it is many in can select
Type.Increase with the double formula of signal rate, requirement of each agreement to link load is further stringent.How to find a
It is the big hot spot of one studied now to meet loss requirement and lower-cost material, so to the fine of the lower PCB trace of full submergence
Model just ever more important.
Existing technology is a kind of aerial simulation model.But this method is not suitable for the cold environment of liquid, and
Modeling granularity is excessively thick, and with the lifting of signal rate, error can be increasing.
The content of the invention
For problem present in correlation technique, the present invention proposes a kind of modeling method and system of printed circuit board,
It can be suitable for the cabling modeling of the lower PCB of full submergence.
The technical proposal of the invention is realized in this way:
According to an aspect of the invention, there is provided a kind of modeling method of printed circuit board, including:S1, according to printing
The size structure model of window after the glass-fiber-fabric fibrillation of circuit board PCB;S2, adds liquid outer cover box in a model, and to liquid
External cover box carries out numerical value electrical parameter setting;S3, setting liquid outer cover box is as radiation border.
According to an embodiment of the invention, step S1 is specifically included:Copper foil type, glass are determined according to the laminated information of PCB
The gel content of cloth type and resin;Determine the roughness of copper, the size of the window after fibrillation after glass-fiber-fabric fibrillation, intertexture side
The dielectric constant of formula and glass-fiber-fabric, and the dielectric constant of resin.
According to an embodiment of the invention, further include after step s 3:S4, sets scope, related algorithm and the receipts of frequency sweep
Standard is held back, and is solved to obtain the scattering parameter of model.
According to an embodiment of the invention, in step s 2, the setting of numerical value electrical parameter is carried out to liquid outer cover box is:It is right
The dielectric constant of liquid outer cover box is configured.
According to another aspect of the present invention, there is provided a kind of modeling of printed circuit board, including:First modeling mould
Block, the size for the window after the glass-fiber-fabric fibrillation according to printing board PCB build model;Second modeling module, for
Liquid outer cover box is added in model, and numerical value electrical parameter setting is carried out to liquid outer cover box;Border setting module, is used for
Liquid outer cover box is set as radiation border.
According to an embodiment of the invention, the first modeling module includes:Material fitting unit, for being believed according to the lamination of PCB
Breath determines the gel content of copper foil type, glass-fiber-fabric type and resin;Parameter determination unit, for determining the roughness of copper, glass
The dielectric constant of the size of the window after fibrillation after fine cloth fibrillation, interleaving mode and glass-fiber-fabric, and the dielectric constant of resin.
According to an embodiment of the invention, modeling further includes:Module is solved, for the scope for setting frequency sweep, related calculation
Method and convergence, and solved to obtain the scattering parameter of model.
According to an embodiment of the invention, numerical value electrically sets the setting for the dielectric constant for being liquid outer cover box.
The modeling method of the PCB of the present invention is suitable for the cabling modeling of the lower PCB of full submergence, and take into account the coarse of copper foil
Degree, the interleaving mode of glass-fiber-fabric, the type of resin, so as to reduce model granularity, makes simulation result more accurate.
Brief description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to institute in embodiment
Attached drawing to be used is needed to be briefly described, it should be apparent that, drawings in the following description are only some implementations of the present invention
Example, for those of ordinary skill in the art, without creative efforts, can also obtain according to these attached drawings
Obtain other attached drawings.
Fig. 1 is the flow chart of the modeling method of printed circuit board according to embodiments of the present invention;
Fig. 2 is the modeling schematic diagram of the different step of the modeling method of printed circuit board according to embodiments of the present invention.
Embodiment
Below in conjunction with the attached drawing in the embodiment of the present invention, the technical solution in the embodiment of the present invention is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art's all other embodiments obtained, belong to what the present invention protected
Scope.
With reference to shown in Fig. 1 and Fig. 2, the modeling method 10 of printed circuit board according to embodiments of the present invention, including following step
Suddenly:
S12, model is built according to the size of the window after the glass-fiber-fabric fibrillation of printing board PCB;
S14, adds liquid outer cover box in a model, and carries out numerical value electrical parameter setting to liquid outer cover box;
S16, setting liquid outer cover box is as radiation border.
The above-mentioned technical proposal of the present invention, braiding modeling is carried out according to the size of the window after the actual fibrillation of glass-fiber-fabric, can be with
Emulate the influence of glass effect;In addition, by adding liquid outer cover box, can the cold environment of simulated solution, suitable under full submergence
The cabling modeling of PCB.
In one embodiment, step S12 specifically includes following steps:S122, copper foil is determined according to the laminated information of PCB
The gel content of type, glass-fiber-fabric type and resin;S124, determines the roughness of copper, the window after fibrillation after glass-fiber-fabric fibrillation
Size, dielectric constant Dk, Df of interleaving mode and glass-fiber-fabric, and dielectric constant Dk, Df of resin.Due to consideration that
The roughness of copper foil, the interleaving mode of glass-fiber-fabric, the type of resin, reduce model granularity so that simulation result is more accurate.
In step S14, it is the dielectric to liquid outer cover box that the setting of numerical value electrical parameter is carried out to liquid outer cover box
Constant Dk, Df are configured.
As shown in Figure 1, modeling method 10 further includes after step S16:S18, set the scope of frequency sweep, related algorithm and
Convergence, and solved to obtain the scattering parameter of model.
In a specific embodiment, with reference to shown in Fig. 2, a work can be created first in HFSS simulation softwares
Journey, sets final drive as resolving type.According to selected laminated information, determine copper foil type, the type of glass-fiber-fabric with
And the gel content of resin, the numerical value being fitted in conjunction with plate factory feedback information and material determine the roughness of copper, after glass-fiber-fabric fibrillation
Window size, interleaving mode and dielectric constant Dk, Df value, and dielectric constant Dk, Df value of resin.Set in HFSS
Good above-mentioned parameter, after being built into model, adds cabling, port and liquid outer cover box, and need to liquid outer cover box into
The setting of row dielectric constant Dk, Df value.Liquid outer cover box is reset as radiation border, sets the scope of frequency sweep, related calculation
Method and convergence, are finally solved to obtain the scattering parameter (S parameter) of the model.
Due to glass-fiber-fabric Dk values be about 6, and count fat Dk values be about 3, this cause PCB trace on glass-fiber-fabric with window on
The Dk values of Shi Jiezhi have a greater change.Under the digital rate of high frequency or hypervelocity, the Dk differences of these area of isolation have can
The deviation (Skew) between large effect, such as impedance continuity, differential signal and insertion damage can be caused to circuit performance
Consumption etc..Herein, influence of the glass effect to S parameter can also be contrasted by adjusting the direction of cabling, it is high as instructing
The foundation of fast cabling optimization.
In conclusion the modeling method of the PCB of the present invention is suitable for the cabling modeling of the lower PCB of full submergence, and take into account
The roughness of copper foil, the interleaving mode of glass-fiber-fabric, the type of resin, so as to reduce model granularity, makes simulation result more smart
Really.
In addition, according to an embodiment of the invention, a kind of modeling of printed circuit board is additionally provided, including be linked in sequence
With lower module:First modeling module, the size for the window after the glass-fiber-fabric fibrillation according to printing board PCB build mould
Type;Second modeling module, numerical value electrical parameter is carried out for adding liquid outer cover box in a model, and to liquid outer cover box
Set;Border setting module, for setting liquid outer cover box as radiation border.
In one embodiment, the first modeling module includes what is be linked in sequence:Material fitting unit, for according to PCB's
Laminated information determines the gel content of copper foil type, glass-fiber-fabric type and resin;Parameter determination unit, for determining the coarse of copper
Degree, the dielectric constant of the size of the window after fibrillation after glass-fiber-fabric fibrillation, interleaving mode and glass-fiber-fabric, and the dielectric of resin
Constant.
In one embodiment, modeling can also include:Module is solved, for the scope for setting frequency sweep, related calculation
Method and convergence, and solved to obtain the scattering parameter of model.
Wherein, numerical value electrical parameter sets the setting for the dielectric constant for being liquid outer cover box.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
With within principle, any modification, equivalent replacement, improvement and so on, should all be included in the protection scope of the present invention god.