CN-122021544-A - PCB board glass fiber effect evaluation method, device, electronic equipment and program product

CN122021544ACN 122021544 ACN122021544 ACN 122021544ACN-122021544-A

Abstract

The invention discloses a method, a device, electronic equipment and a program product for evaluating glass fiber effect of a PCB (printed circuit board), which comprise the steps of dividing a target PCB into a plurality of warp-weft glass fiber overlapping areas and a plurality of warp-glass fiber areas, and determining an equivalent RLGC model; the method comprises the steps of extracting first RLGC matrix parameters of a medium part through a two-dimensional field solver, calculating second RLGC matrix parameters of a glass fiber part through a layer equivalent model and a parallel plate capacitance model, determining a transmission parameter matrix, determining a target transmission parameter matrix of a complete differential transmission line structure of a target PCB according to a plurality of warp-weft glass fiber overlapping areas and transmission parameter matrices corresponding to the warp-glass fiber areas, determining scattering parameters of the target PCB according to the target transmission parameter matrix, and calculating glass fiber effect performance parameters. The invention improves the efficiency of the evaluation of the glass fiber effect of the PCB board on the premise of ensuring the precision, saves the calculation force resource, and can be applied to the technical field of PCB design.

Inventors

ZHANG MUSHUI
JIAN ZIJUN
LI YUYING
WANG ZIXIN
ZHU YONGMING

Assignees

中山大学
广东生益科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260401

Claims (10)

1. The method for evaluating the glass fiber effect of the PCB is characterized by comprising the following steps of: Dividing a target PCB board into a plurality of warp-weft glass fiber overlapping areas and a plurality of warp-weft glass fiber areas, and respectively determining equivalent RLGC models corresponding to the warp-weft glass fiber overlapping areas and the warp-weft glass fiber areas; According to the equivalent RLGC model, extracting a first RLGC matrix parameter of a medium part through a two-dimensional field solver, and calculating a second RLGC matrix parameter of the glass fiber part through a layer equivalent model and a parallel plate capacitance model; determining a transmission parameter matrix of the equivalent RLGC model according to the first RLGC matrix parameters and the second RLGC matrix parameters; Determining a target transmission parameter matrix of a complete differential transmission line structure of the target PCB according to the plurality of warp-weft glass fiber overlapping areas and the transmission parameter matrices corresponding to the plurality of warp-weft glass fiber areas; and determining scattering parameters of the target PCB according to the target transmission parameter matrix, and further calculating glass fiber effect performance parameters of the target PCB according to the scattering parameters.
2. The method for evaluating glass fiber effect of a PCB board according to claim 1, wherein the dividing the target PCB board into a plurality of warp-weft glass fiber overlapping areas and a plurality of warp-glass fiber areas, and determining equivalent RLGC models corresponding to the warp-weft glass fiber overlapping areas and the warp-glass fiber areas, respectively, specifically comprises: Dividing the target PCB into a plurality of modeling units according to the length; determining a plurality of warp and weft glass fiber overlapping areas and a plurality of warp glass fiber areas contained in each modeling unit; Constructing a corresponding first equivalent RLGC model according to the geometric parameters and the dielectric parameters of the dielectric layers and the transmission lines in the warp-weft glass fiber overlapping area; And constructing a corresponding second equivalent RLGC model according to the geometric parameters and the dielectric parameters of the dielectric layers and the transmission lines of the warp-wise glass fiber region.
3. The method for evaluating the glass fiber effect of the PCB board according to claim 1, wherein the extracting the first RLGC matrix parameters of the medium portion by the two-dimensional field solver according to the equivalent RLGC model, and calculating the second RLGC matrix parameters of the glass fiber portion by the layer equivalent model and the parallel plate capacitance model specifically comprises: Dividing the equivalent RLGC model into the medium portion containing only homogeneous medium and the glass fiber portion containing medium and glass fiber; Inputting the line width, the medium thickness and the conductivity of the medium part into a two-dimensional field solver to obtain the first RLGC matrix parameters; The glass fiber in the glass fiber part is equivalent to a glass fiber layer with unchanged thickness through a layer equivalent model; Calculating the capacitance variation and the conductance variation caused by the glass fiber layer through a parallel plate capacitance model; Inputting the line width, the medium thickness and the conductivity of the glass fiber part into a two-dimensional field solver to obtain a third RLGC matrix parameter; and correcting the capacitance value and the conductance value of the third RLGC matrix parameter according to the capacitance variation and the conductance variation to obtain the second RLGC matrix parameter.
4. The method for evaluating glass fiber effect of PCB board according to claim 1, wherein determining the transmission parameter matrix of the equivalent RLGC model according to the first RLGC matrix parameter and the second RLGC matrix parameter specifically comprises: Respectively converting the first RLGC matrix parameters and the second RLGC matrix parameters into Z parameters of 4 ports to obtain a first transmission parameter matrix of the medium part and a second transmission parameter matrix of the glass fiber part; And determining the transmission parameter matrix of the equivalent RLGC model according to the product of the first transmission parameter matrix and the second transmission parameter matrix.
5. The method for evaluating glass fiber effect of PCB board according to claim 2, wherein determining the target transmission parameter matrix of the complete differential transmission line structure of the target PCB board according to the plurality of the warp-weft glass fiber overlapping areas and the transmission parameter matrix corresponding to the plurality of the warp-glass fiber areas specifically comprises: Determining a first unit transmission parameter matrix according to the product of the transmission parameter matrices corresponding to the plurality of warp-weft glass fiber overlapping areas contained in the modeling unit; determining a second unit transmission parameter matrix according to the product of the transmission parameter matrices corresponding to the warp glass fiber areas included by the modeling unit; determining a unit transmission parameter matrix of the modeling unit according to the product of the first unit transmission parameter matrix and the second unit transmission parameter matrix; and determining the target transmission parameter matrix according to the product of the unit transmission parameter matrices corresponding to the modeling units contained in the target PCB.
6. The method for evaluating glass fiber effect of a PCB board according to any one of claims 1 to 5, wherein the glass fiber effect performance parameter comprises at least one of differential insertion loss, common mode rejection ratio, differential transmission line delay difference and eye diagram.
7. The utility model provides a PCB panel glass fiber effect evaluation device which characterized in that includes: The area modeling module is used for dividing the target PCB into a plurality of warp-weft glass fiber overlapping areas and a plurality of warp-glass fiber areas, and respectively determining the warp-weft glass fiber overlapping areas and equivalent RLGC models corresponding to the warp-glass fiber areas; The parameter solving module is used for solving the first RLGC matrix parameters of the medium part through a two-dimensional field solver according to the equivalent RLGC model, and calculating the second RLGC matrix parameters of the glass fiber part through a layer equivalent model and a parallel plate capacitance model; the parameter cascade module is used for determining a transmission parameter matrix of the equivalent RLGC model according to the first RLGC matrix parameters and the second RLGC matrix parameters; the parameter determining module is used for determining a target transmission parameter matrix of the complete differential transmission line structure of the target PCB board according to the plurality of warp-weft glass fiber overlapping areas and the transmission parameter matrices corresponding to the plurality of warp glass fiber areas; And the glass fiber effect evaluation module is used for determining the scattering parameters of the target PCB according to the target transmission parameter matrix, and further calculating the glass fiber effect performance parameters of the target PCB according to the scattering parameters.
8. An electronic device, comprising: At least one processor; at least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor is caused to implement a PCB board fiberglass effect evaluation method as claimed in any one of claims 1 to 6.
9. A computer-readable storage medium in which a processor-executable program is stored, characterized in that the processor-executable program is for performing a PCB board glass fiber effect evaluation method according to any one of claims 1 to 6 when being executed by a processor.
10. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements a method for evaluating the glass fiber effect of a PCB board as claimed in any one of claims 1 to 6.

Description

PCB board glass fiber effect evaluation method, device, electronic equipment and program product Technical Field The invention relates to the technical field of PCB design, in particular to a method, a device, electronic equipment and a program product for evaluating glass fiber effect of a PCB. Background As communication system signal rate frequencies gradually advance toward higher speeds, signal integrity is critical to ensuring system performance. The glass fiber effect becomes a non-negligible phenomenon, and directly influences the characteristic impedance, delay and other performance parameters of the transmission line. The influence of the glass fiber effect on the high-speed signal is mainly reflected in two aspects, namely, on one hand, the periodic fluctuation of the characteristic impedance of the transmission line is caused, so that the resonance of the signal is caused, and on the other hand, the transmission delay difference is caused between the differential transmission lines, the symmetry of the differential signal is destroyed, and the signal integrity problems such as error codes, mode conversion and the like are caused. To evaluate the specific impact of the glass fiber effect, the dielectric layer of the printed circuit board and the transmission line structure need to be modeled appropriately. However, the cross section of the glass fiber bundles is approximately elliptical, and the glass fiber bundles are arranged in a medium layer in a warp-weft interweaving mode, so that the structure is complex and has microscopic periodicity, and the complex structure brings great difficulty to accurate modeling. At present, modeling methods for glass fiber effect are mainly divided into three-dimensional modeling and two-dimensional modeling: 1) The three-dimensional modeling method aims at reconstructing a three-dimensional space structure of the glass fiber in the medium layer and performing simulation analysis by utilizing three-dimensional full-wave simulation software, or simplifying the cross section of the glass fiber into a rectangular cross section, optimizing an interweaving structure, balancing simulation complexity and not sacrificing much accuracy. 2) Two-dimensional modeling, namely a modeling method which is provided for solving the efficiency bottleneck of three-dimensional modeling. The method aims at the cross-section structure of the dielectric layer and the transmission line, and obtains corresponding performance parameter indexes by analyzing electromagnetic field distribution of the cross-section structure and utilizing complex calculation, or utilizes a statistical principle to count the change rule of equivalent dielectric constants of various relative positions by utilizing a large number of physical samples of the relative positions of glass fibers and the transmission line, and summarize the specific performance. Although the modeling methods mentioned above all have relatively perfect flow, there are all shortcomings to be solved, which limit their wide application in engineering practice. For the three-dimensional modeling method, the disadvantage is that the process of constructing the actual structure of the glass fiber is very tedious and error-prone. For mainstream commercial three-dimensional electromagnetic simulation software, a built-in basic primitive library (such as cubes, cylinders, spheres and the like) cannot directly generate a glass fiber structure with a cross section similar to ellipse and a wave-shaped interweaved path. Modelers often need to manually approximate the splice through complex boolean operations, scanning operations, etc. In addition, for the medium layer section with elliptic section and warp-weft interweaving, extremely dense mesh subdivision is needed to ensure the precision of field solution, which directly leads to exponential increase of calculation resources (memory occupation and CPU calculation time length), and single simulation takes several hours. The nature of the three-dimensional simulation is not changed even if a simplified attempt is made to model. Therefore, the problem of low three-dimensional simulation efficiency is still outstanding, and the modeling method is difficult to widely apply to a circuit design scene requiring rapid iteration. Compared with the three-dimensional modeling method, the two-dimensional modeling method has the advantages of greatly improving the calculation efficiency, but has the limitation of use. The method is based on complex electromagnetic field theory, involves a large number of complex calculus operations, or requires large-scale statistical sample analysis. This has a high theoretical requirement on the knowledge of the designer, which is not conducive to intuitive understanding and quick verification. In summary, the prior art lacks a method for evaluating the glass fiber effect of a PCB board, which can achieve a good balance among calculation accuracy, efficiency and engineerin