A Thermal Simulation Method and Device for a Rigid-Flex Printed Circuit Board

Abstract

The present invention relates to the technical field of rigid-flex printed circuit boards, and in particular to a thermal simulation method for rigid-flex printed circuit boards. The method includes: obtaining the soft board parameters of a first rigid-flex printed circuit board simulation model, where the simulation model is a preset model of the first rigid-flex printed circuit board in a bent state, and the soft board parameters are the parameters of the soft board of the first rigid-flex printed circuit board; obtaining the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient according to the simulation model and the soft board parameters; adjusting the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain a target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies the temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient. This method can accurately represent the thermal conductivity characteristics of the rigid-flex printed circuit board in the bent state and improve the thermal simulation efficiency of the rigid-flex printed circuit board.

Description

Technical Field

[0001] The present invention relates to the technical field of rigid-flex printed circuit boards, and particularly to a thermal simulation method and device for rigid-flex printed circuit boards. Background Art

[0002] Rigid-flex printed circuit boards are widely used in vehicle-mounted or mobile phone camera modules. In the actual application of rigid-flex printed circuit boards, the flexible printed circuit board of the rigid-flex printed circuit board will be bent in a certain form inside the vehicle-mounted camera or inside the mobile phone. In the bent state of the rigid-flex printed circuit board, the existing solutions have low accuracy in expressing the anisotropic thermal conductivity characteristics of the rigid-flex printed circuit board, which affects the thermal detection of products equipped with rigid-flex printed circuit boards. Summary of the Invention

[0003] By providing a thermal simulation method and device for a rigid-flex printed circuit board, embodiments of the present application solve the technical problem of low accuracy in expressing the anisotropic thermal conductivity characteristics of a rigid-flex printed circuit board in the prior art, and achieve the technical effects of accurately expressing the thermal conductivity characteristics of the rigid-flex printed circuit board in the bent state, improving the thermal simulation efficiency of the rigid-flex printed circuit board, and enhancing the accuracy of thermal detection of products equipped with rigid-flex printed circuit boards.

[0004] In a first aspect, an embodiment of the present invention provides a thermal simulation method for a rigid-flex printed circuit board, including:

[0005] Obtain the flexible printed circuit board parameters of a first rigid-flex printed circuit board simulation model, where the simulation model is a preset model of the first rigid-flex printed circuit board in a bent state, and the flexible printed circuit board parameters are the parameters of the flexible printed circuit board of the first rigid-flex printed circuit board;

[0006] According to the simulation model and the flexible printed circuit board parameters, obtain the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient;

[0007] According to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, adjust the initial isotropic thermal conductivity coefficient of the simulation model to obtain a target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies a temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

[0008] Preferably, the flexible printed circuit board includes N copper foil layers, N is a positive integer not less than 1, and obtaining the flexible printed circuit board parameters includes:

[0009] Obtain the copper content rate of each copper foil layer in the N copper foil layers and the stacked structure thickness of the flexible printed circuit board, where the stacked structure thickness is the thickness of the flexible printed circuit board in the bent state;

[0010] Obtaining the anisotropic thermal conductivity coefficient of the simulation model according to the simulation model and the flexible board parameters includes:

[0011] Obtaining the anisotropic thermal conductivity coefficient according to the simulation model, the copper content rate of each copper foil layer, and the stacking thickness.

[0012] Preferably, obtaining the copper content rate of each copper foil layer in the N copper foil layers includes:

[0013] Obtaining the copper trace distribution area of each copper foil layer and the total area of the flexible board;

[0014] Obtaining the copper content rate of each copper foil layer according to the copper trace distribution area of each copper foil layer and the total area.

[0015] Preferably, adjusting the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain the target isotropic thermal conductivity coefficient includes:

[0016] Adjusting the initial isotropic thermal conductivity coefficient according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain the adjusted isotropic thermal conductivity coefficient;

[0017] If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is not greater than the temperature difference threshold, then determining the adjusted isotropic thermal conductivity coefficient as the target isotropic thermal conductivity coefficient.

[0018] Preferably, after obtaining the adjusted isotropic thermal conductivity coefficient, it further includes:

[0019] If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is greater than the temperature difference threshold, then continue to adjust the adjusted isotropic thermal conductivity coefficient until the target isotropic thermal conductivity coefficient is obtained.

[0020] Preferably, after obtaining the target isotropic thermal conductivity coefficient, it further includes:

[0021] Obtaining the anisotropic thermal conductivity coefficient of the second rigid-flexible printed circuit board simulation model, where the number of copper foil layers of the flexible board of the second rigid-flexible printed circuit board is the same as that of the flexible board of the first rigid-flexible printed circuit board;

[0022] Based on the ratio of the anisotropic thermal conductivity coefficient of the first flexible-rigid board simulation model to the target isotropic thermal conductivity coefficient, and the anisotropic thermal conductivity coefficient of the second flexible-rigid board simulation model, the isotropic thermal conductivity coefficient of the second flexible-rigid board simulation model is obtained.

[0023] Preferably, the simulation model is a splicing model composed of the flexible board model and the rigid board model of the first flexible-rigid board.

[0024] Based on the same inventive concept, in a second aspect, the present invention further provides a thermal simulation device for a flexible-rigid board, including:

[0025] A first acquisition module, configured to acquire the flexible board parameters of the first flexible-rigid board simulation model, where the simulation model is a preset model of the first flexible-rigid board in a bent state, and the flexible board parameters are the parameters of the flexible board of the first flexible-rigid board;

[0026] A second acquisition module, configured to obtain the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient according to the simulation model and the flexible board parameters;

[0027] An adjustment module, configured to adjust the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain a target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies a temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

[0028] Based on the same inventive concept, in a third aspect, the present invention provides a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, and when the processor executes the program, the steps of the thermal simulation method for a flexible-rigid board are implemented.

[0029] Based on the same inventive concept, in a fourth aspect, the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the steps of the thermal simulation method for a flexible-rigid board are implemented.

[0030] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0031] In an embodiment of the present invention, after obtaining the flexible board parameters of the first rigid-flex board simulation model, according to the simulation model and the flexible board parameters, the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient are obtained. Wherein, the simulation model is a preset model of the first rigid-flex board in a bent state, and the flexible board parameters are the parameters of the flexible board of the first rigid-flex board. Here, the anisotropic thermal conductivity coefficient of the simulation model with high reliability and accuracy, as well as the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, can be directly obtained according to the flexible board parameters of the first rigid-flex board simulation model. Then, according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, the initial isotropic thermal conductivity coefficient of the simulation model is adjusted to obtain the target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies the temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient. Here, through the anisotropic thermal conductivity coefficient of the simulation model of the first rigid-flex board, the isotropic thermal conductivity coefficient of the simulation model is deduced, and then through the isotropic thermal conductivity coefficient, thermal analysis of the simulation model is carried out to accurately describe the thermal conductivity characteristics of the rigid-flex board in a bent state, improve the thermal simulation efficiency of the rigid-flex board, and enhance the accuracy of thermal detection of products provided with the rigid-flex board. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0033] Figure 1 The schematic flow chart of the steps of the thermal simulation method of the rigid-flex board in the embodiment of the present invention is shown;

[0034] Figure 2 The schematic structural diagram of Model A in the embodiment of the present invention is shown;

[0035] Figure 3 The schematic structural diagram of Model B in the embodiment of the present invention is shown;

[0036] Figure 4 The thermal analysis result diagram of Model A and Model B in the embodiment of the present invention is shown;

[0037] Figure 5 The schematic structural diagram of Model C in the embodiment of the present invention is shown;

[0038] Figure 6 The copper trace schematic diagram of the copper foil layer of the flexible board of Model C in the embodiment of the present invention is shown;

[0039] Figure 7Shows the thermal analysis result diagrams of the C1 model and the C2 model in the embodiments of the present invention;

[0040] Figure 8 Shows the schematic diagram of the modules of the thermal simulation device for the rigid-flex printed circuit board in the embodiments of the present invention;

[0041] Figure 9 Shows the schematic structural diagram of a computer device in the embodiments of the present invention. Detailed implementation manners

[0042] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0043] Embodiment 1

[0044] The first embodiment of the present invention provides a thermal simulation method for a rigid-flex printed circuit board, as Figure 1 shown, including:

[0045] S101, obtaining the flexible board parameters of the first rigid-flex printed circuit board simulation model, where the simulation model is a preset model of the first rigid-flex printed circuit board in a bent state, and the flexible board parameters are the parameters of the flexible board of the first rigid-flex printed circuit board;

[0046] S102, obtaining the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient according to the simulation model and the flexible board parameters;

[0047] S103, adjusting the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain the target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies the temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

[0048] In this embodiment, the rigid-flex board can be applied to electronic devices such as mobile phones or vehicle-mounted cameras, serving as a physical and electrical connection. For a camera module, it usually includes a rigid-flex board and a chip. The chip is disposed in the rigid part of the rigid-flex board. Among them, the chip includes a driving chip and a vertical cavity surface emitting laser (VCSEL) chip. When the camera module operates, the chip generates heat, which is transferred to the rigid-flex board. By performing a thermal analysis on the rigid-flex board, the temperature range during the operation of the chip can be obtained. The temperature change range during the operation of the chip is an important indicator for measuring the working performance of the camera module. If the temperature range obtained from the thermal simulation during the operation of the chip is too high, then during product design, some costs need to be sacrificed to increase heat dissipation components or increase the heat dissipation space. If the temperature range obtained from the thermal simulation during the operation of the chip is relatively low, then the heat dissipation components can be reduced or the product size can be reduced to save costs and achieve a small size. Therefore, during the design process of the camera module, the operating temperature of the chip needs to be limited. By performing a thermal analysis on the rigid-flex board, it can be evaluated whether the temperature of the chip meets the temperature requirements. The accuracy of the thermal analysis result of the rigid-flex board is crucial for the final evaluation, which is related to key indicators such as the cost and size of the product.

[0049] Next, in combination with Figure 1 the following will detail the specific implementation steps of the thermal simulation method for the rigid-flex board provided in this embodiment:

[0050] First, perform step S101 to obtain the flexible board parameters of the first rigid-flex board simulation model, where the simulation model is a preset model of the first rigid-flex board in a bent state, and the flexible board parameters are the parameters of the flexible board of the first rigid-flex board.

[0051] Specifically, when designing a rigid-flex board, it is often the case that electronic engineers design and provide layout data (i.e., routing files) for production. For the thermal simulation of the rigid-flex board, the layout data is also often used as the input file for the thermal simulation. Since the simulation model of the first rigid-flex board is a splicing model composed of the flexible board model and the rigid board model of the first rigid-flex board, obtaining the thermal simulation model of the first rigid-flex board means obtaining a simulation model composed of two pieces of layout data in EDA file format and a blank layout data, where the two pieces of layout data in EDA file format are the rigid board 1 and the rigid board 2 of the first rigid-flex board respectively, and a blank layout data replaces the flexible board of the first rigid-flex board.

[0052] To verify whether the simulation model formed by splicing rigid-flex boards can replace the overall simulation model of rigid-flex boards for thermal analysis, a thermal analysis is performed on an overall simulation model A of a rigid-flex board and a simulation model B formed by splicing rigid-flex boards respectively. The parameters of these two simulation models are the same. For example, both simulation models are in a tiled state, and the parameters of the rigid board 1, FPC (Flexible Printed Circuit) flexible board, and rigid board 2 in the two simulation models are the same. Among them, the overall simulation model of the rigid-flex board is layout data in the format of an overall EDA file, and the rigid-flex board in this layout data is continuous and complete.

[0053] As Figure 2 shown, Model A is layout data in the format of an overall EDA file. Model A includes rigid board 1, rigid board 2, and a flexible board. Among them, an FPC flexible board is connected between rigid board 1 and rigid board 2 of Model A, indicating that the rigid-flex board in this layout data is in a continuous and complete state.

[0054] As Figure 3 shown, Model B is a simulation model formed by splicing rigid-flex boards, a model formed by splicing three segments of EDA file format, and these three segments of EDA file format are rigid board 1, FPC flexible board, and rigid board 2 respectively. Therefore, Model B includes rigid board 1, rigid board 2, and a flexible board, and Model B is formed by splicing rigid board 1, rigid board 2, and the flexible board.

[0055] After performing thermal analysis on Model A and Model B respectively, as Figure 4 shown, the highest temperature of the drive chip of Model A is 67.6816 °C, and the highest temperature of the VCSEL chip of Model A is 67.4398 °C. The highest temperature of the drive chip of Model B is 67.5558 °C, and the highest temperature of the VCSEL chip of Model B is 67.3011 °C. It can be seen that the highest temperature of the drive chip of Model A is basically the same as that of Model B, that is, the temperature difference between the two is not greater than 1 °C, and the highest temperature of the VCSEL chip of Model A is basically the same as that of Model B. Therefore, it can be determined that the simulation model formed by splicing rigid-flex boards can replace the overall simulation model of rigid-flex boards for thermal analysis, and the obtained thermal analysis results are also reliable.

[0056] The simulation model composed of the obtained two segments of layout data in EDA file format and a blank layout data is denoted as Model C. As Figure 5 shown, that is, the simulation model of the first rigid-flex board is denoted as Model C, and the parameters of the flexible board in Model C are the same as those of the flexible board in Models A and B, and the parameters of the rigid board in Model C are the same as those of the rigid board in Models A and B. Among them, the blank layout data forms a blank area in Model C. So, as Figure 5As shown in the figure, the C model includes a hard board 1, a blank area, and a hard board 2, and the C model is formed by splicing the hard board 1, the hard board 2, and the blank area. Since the simulation model of the first flexible-rigid board is the preset model of the first flexible-rigid board in the bent state, which represents the preset model of the flexible board of the first flexible-rigid board in the bent state, the blank area in the C model represents the flexible board. Although the flexible board in the C model is in the bent state, indicating that the flexible board of the C model has an arbitrary bent shape, the flexible board parameters of the flexible board itself will not change.

[0057] After obtaining the simulation model C model of the first flexible-rigid board, convert the layout data of the software in the B model into the structural data in the CAD file format to obtain the flexible board parameters. It should be noted that the flexible board in the C model (i.e., the flexible board of the B model) includes N copper foil layers, where N is a positive integer not less than 1. The specific steps to obtain the flexible board parameters are as follows: obtain the copper content rate of each copper foil layer in the N copper foil layers of the flexible board and the stacked structure thickness of the flexible board, where the stacked structure thickness is the thickness of the flexible board in the bent state, and the stacked structure thickness can be directly measured. The specific steps to obtain the copper content rate of each copper foil layer in the N copper foil layers are as follows: first, obtain the copper trace distribution area of each copper foil layer and the total area of the flexible board; according to the copper trace distribution area and the total area of each copper foil layer, obtain the copper content rate of each copper foil layer.

[0058] For example, the flexible board of the C model includes two copper foil layers. As Figure 6 shown, Cu1 is the copper trace distribution of the first copper foil layer, and the non-white area in Cu1 is the copper trace distribution area of the first copper foil layer. Cu2 is the copper trace distribution of the second copper foil layer, and the non-white area in Cu2 is the copper trace distribution area of the second copper foil layer. F is the total area of the flexible board. According to the copper trace distribution area of each copper foil layer and the total area of the flexible board, obtain the copper content rate of each copper foil layer. It is calculated that the copper trace distribution area of the first copper foil layer is 74.7%, and the copper trace distribution area of the second copper foil layer is 65.9%.

[0059] After obtaining the flexible board parameters of the simulation model C model of the first flexible-rigid board, execute step S102. According to the simulation model and the flexible board parameters, obtain the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

[0060] Specifically, according to the simulation model C model, the copper content rate of each copper foil layer in the C model flexible board, and the stacked structure thickness of the C model flexible board, obtain the anisotropic thermal conductivity coefficient of the C model. The anisotropic thermal conductivity coefficient can be directly calculated by thermal simulation software, and the anisotropic thermal conductivity coefficient of the C model is 88.3034 watts per meter per degree (W / (m·K)).

[0061] Then, perform step S103. Adjust the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain the target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies the temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

[0062] Specifically, when adjusting the initial isotropic thermal conductivity coefficient according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, the adjusted isotropic thermal conductivity coefficient is obtained; if the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is not greater than the temperature difference threshold, then the adjusted isotropic thermal conductivity coefficient is determined as the target isotropic thermal conductivity coefficient.

[0063] It should be noted that the temperature difference threshold is set according to actual requirements, such as the temperature difference threshold is set to 1°C, 2°C or 5°C, etc. The junction temperature of the simulation model is represented by the highest temperature of the driving chip in the simulation model, or by the highest temperature of the VCSEL chip in the simulation model, or by the highest temperature of the driving chip and the highest temperature of the VCSEL chip in the simulation model. The first method for adjusting the initial isotropic thermal conductivity coefficient: First, set an initial isotropic thermal conductivity coefficient of a simulation model C model according to the experience of the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient. Then, according to the initial isotropic thermal conductivity coefficient, obtain the junction temperature of the simulation model corresponding to the initial isotropic thermal conductivity coefficient, and then compare the junction temperature of the simulation model corresponding to the initial isotropic thermal conductivity coefficient with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient. If the junction temperature of the simulation model corresponding to the initial isotropic thermal conductivity coefficient is greater than the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, then adjust the initial isotropic thermal conductivity coefficient downward. If the junction temperature of the simulation model corresponding to the initial isotropic thermal conductivity coefficient is less than the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, then adjust the initial isotropic thermal conductivity coefficient upward.

[0064] The second method for adjusting the initial isotropic thermal conductivity coefficient: Set the initial isotropic thermal conductivity coefficient to zero and incrementally adjust it from zero upward. Each time the isotropic thermal conductivity coefficient is adjusted, compare the junction temperature of the simulation model corresponding to the isotropic thermal conductivity coefficient with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient. When the junction temperature of the simulation model corresponding to the isotropic thermal conductivity coefficient gradually approaches the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, narrow the adjustment range of the isotropic thermal conductivity coefficient at this time and accurately adjust to obtain the target isotropic thermal conductivity coefficient, so that the temperature difference between the junction temperature of the simulation model corresponding to the isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is not greater than the temperature difference threshold.

[0065] Such as Figure 7As shown, according to the anisotropic thermal conductivity coefficient, a thermal analysis is performed on the C model to obtain the C1 model. According to the adjusted isotropic thermal conductivity coefficient, a thermal analysis is performed on the C model to obtain the C2 model, where the value of the isotropic thermal conductivity coefficient is 50 W / (m·K). From Figure 7 it can be seen that the maximum temperature of the driving chip of the C1 model is 67.1888 °C, the maximum temperature of the VCSEL chip is 66.9638 °C, the maximum temperature of the driving chip of the C2 model is 67.5272 °C, and the maximum temperature of the VCSEL chip is 67.2704 °C. If the temperature difference between the maximum temperature of the driving chip of the C1 model and the maximum temperature of the driving chip of the C2 model is not greater than the temperature difference threshold, and the temperature difference between the maximum temperature of the VCSEL chip of the C1 model and the maximum temperature of the VCSEL chip of the C2 model is not greater than the temperature difference threshold, then the adjusted isotropic thermal conductivity coefficient corresponding to the C2 model is determined as the target isotropic thermal conductivity coefficient.

[0066] If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is greater than the temperature difference threshold, then continue to adjust the adjusted isotropic thermal conductivity coefficient until the target isotropic thermal conductivity coefficient is obtained.

[0067] In this embodiment, the isotropic thermal conductivity coefficient of the simulation model is deduced from the anisotropic thermal conductivity coefficient of the simulation model of the first rigid-flex printed circuit board, and then the thermal analysis of the simulation model is performed through the isotropic thermal conductivity coefficient, accurately expressing the thermal conductivity characteristics of the rigid-flex printed circuit board in the bent state, improving the thermal simulation efficiency of the rigid-flex printed circuit board, and enhancing the accuracy of the thermal detection of the product provided with the rigid-flex printed circuit board.

[0068] After obtaining the target isotropic thermal conductivity coefficient, the isotropic thermal conductivity coefficient of other rigid-flex printed circuit boards with the same number of copper foil layers as the flexible board of the first rigid-flex printed circuit board is deduced through the target isotropic thermal conductivity coefficient of the first rigid-flex printed circuit board. The specific deduction method is as follows:

[0069] First, obtain the anisotropic thermal conductivity coefficient of the simulation model of the second rigid-flex printed circuit board, where the number of copper foil layers of the flexible board of the second rigid-flex printed circuit board is the same as that of the flexible board of the first rigid-flex printed circuit board. Then, according to the ratio of the anisotropic thermal conductivity coefficient of the simulation model of the first rigid-flex printed circuit board to the target isotropic thermal conductivity coefficient, and the anisotropic thermal conductivity coefficient of the simulation model of the second rigid-flex printed circuit board, obtain the isotropic thermal conductivity coefficient of the simulation model of the second rigid-flex printed circuit board.

[0070] For example, the flexible board of the first rigid-flex board includes two copper foil layers, and the flexible board of the second rigid-flex board also includes two copper foil layers. Through the steps described above, the anisotropic thermal conductivity coefficient of the simulation model of the first rigid-flex board can be directly obtained as 88, its target isotropic thermal conductivity coefficient is 40, and the anisotropic thermal conductivity coefficient of the simulation model of the second rigid-flex board is 90. First, obtain the ratio of the anisotropic thermal conductivity coefficient of the simulation model of the first rigid-flex board to its target isotropic thermal conductivity coefficient, and the result is 88 / 40 = 2.2. Then, based on this result and the anisotropic thermal conductivity coefficient of the simulation model of the second rigid-flex board, the isotropic thermal conductivity coefficient of the simulation model of the second rigid-flex board is obtained as 90 / 2.2 = 40.9091.

[0071] In this embodiment, after obtaining the target isotropic thermal conductivity coefficient of a certain rigid-flex board, the isotropic thermal conductivity coefficients of other rigid-flex boards with the same number of copper foil layers as the flexible board of this rigid-flex board can be deduced through the target isotropic thermal conductivity coefficient of this rigid-flex board, which is convenient for quickly obtaining the isotropic thermal conductivity coefficients of other rigid-flex boards with the same number of copper foil layers as the flexible board of this rigid-flex board, accurately expressing the thermal conductivity characteristics of the rigid-flex board in the bent state, improving the thermal simulation efficiency of the rigid-flex board, and enhancing the accuracy of the thermal detection of the product provided with the rigid-flex board.

[0072] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0073] In this embodiment, after obtaining the flexible board parameters of the simulation model of the first rigid-flex board, according to the simulation model and the flexible board parameters, the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient are obtained. Among them, the simulation model is a preset model of the first rigid-flex board in the bent state, and the flexible board parameters are the parameters of the flexible board of the first rigid-flex board. Here, the anisotropic thermal conductivity coefficient of the simulation model with high reliability and accuracy, and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient can be directly obtained according to the flexible board parameters of the simulation model of the first rigid-flex board. Then, according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, the initial isotropic thermal conductivity coefficient of the simulation model is adjusted to obtain the target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies the temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient. Here, through the anisotropic thermal conductivity coefficient of the simulation model of the first rigid-flex board, the isotropic thermal conductivity coefficient of the simulation model is deduced, and then through the isotropic thermal conductivity coefficient, the thermal analysis of the simulation model is unified, accurately expressing the thermal conductivity characteristics of the rigid-flex board in the bent state, improving the thermal simulation efficiency of the rigid-flex board, and enhancing the accuracy of the thermal detection of the product provided with the rigid-flex board.

[0074] Embodiment 2

[0075] Based on the same inventive concept, a second embodiment of the present invention further provides a thermal simulation device for a rigid-flex printed circuit board, as Figure 8 shown, comprising:

[0076] A first acquisition module 201, configured to acquire the soft board parameters of a first rigid-flex printed circuit board simulation model, wherein the simulation model is a preset model of the first rigid-flex printed circuit board in a bent state, and the soft board parameters are the parameters of the soft board of the first rigid-flex printed circuit board;

[0077] A second acquisition module 202, configured to obtain the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient according to the simulation model and the soft board parameters;

[0078] An adjustment module 203, configured to adjust the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain a target isotropic thermal conductivity coefficient, wherein the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies a temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

[0079] As an optional embodiment, the soft board includes N copper foil layers, N is a positive integer not less than 1, and the first acquisition module 201 is configured to acquire the soft board parameters, including:

[0080] Acquiring the copper content rate of each copper foil layer in the N copper foil layers and the stacking thickness of the soft board, wherein the stacking thickness is the thickness of the soft board in the bent state;

[0081] The second acquisition module 202 is configured to obtain the anisotropic thermal conductivity coefficient of the simulation model according to the simulation model and the soft board parameters, including:

[0082] Obtaining the anisotropic thermal conductivity coefficient according to the simulation model, the copper content rate of each copper foil layer, and the stacking thickness.

[0083] As an optional embodiment, the acquiring the copper content rate of each copper foil layer in the N copper foil layers includes:

[0084] Acquiring the copper trace distribution area of each copper foil layer and the total area of the soft board;

[0085] Obtaining the copper content rate of each copper foil layer according to the copper trace distribution area of each copper foil layer and the total area.

[0086] As an alternative embodiment, the adjustment module 203 is configured to adjust the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, so as to obtain a target isotropic thermal conductivity coefficient, including:

[0087] Adjust the initial isotropic thermal conductivity coefficient according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain an adjusted isotropic thermal conductivity coefficient;

[0088] If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is not greater than the temperature difference threshold, then determine the adjusted isotropic thermal conductivity coefficient as the target isotropic thermal conductivity coefficient.

[0089] As an alternative embodiment, the adjustment module 203 is configured to:

[0090] If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is greater than the temperature difference threshold, then continue to adjust the adjusted isotropic thermal conductivity coefficient until the target isotropic thermal conductivity coefficient is obtained.

[0091] As an alternative embodiment, after obtaining the target isotropic thermal conductivity coefficient, the adjustment module 203 further includes:

[0092] Obtain the anisotropic thermal conductivity coefficient of the second flexible-rigid printed circuit board simulation model, where the number of copper foil layers of the flexible board of the second flexible-rigid printed circuit board is the same as the number of copper foil layers of the flexible board of the first flexible-rigid printed circuit board;

[0093] According to the ratio of the anisotropic thermal conductivity coefficient of the first flexible-rigid printed circuit board simulation model to the target isotropic thermal conductivity coefficient, and the anisotropic thermal conductivity coefficient of the second flexible-rigid printed circuit board simulation model, obtain the isotropic thermal conductivity coefficient of the second flexible-rigid printed circuit board simulation model.

[0094] As an alternative embodiment, the simulation model is a splicing model composed of a flexible board model and a rigid board model of the first flexible-rigid printed circuit board.

[0095] Since the thermal simulation device of the flexible-rigid printed circuit board introduced in this embodiment is the device adopted for implementing the thermal simulation method of the flexible-rigid printed circuit board in Embodiment 1 of the present application, based on the thermal simulation method of the flexible-rigid printed circuit board introduced in Embodiment 1 of the present application, those skilled in the art can understand the specific implementation manners and various variations of the thermal simulation device of the flexible-rigid printed circuit board in this embodiment. Therefore, the implementation of how the thermal simulation device of the flexible-rigid printed circuit board realizes the method in Embodiment 1 of the present application will not be described in detail herein. As long as the device adopted by those skilled in the art to implement the thermal simulation method of the flexible-rigid printed circuit board in Embodiment 1 of the present application falls within the scope of protection of the present application.

[0096] Embodiment 3

[0097] Based on the same inventive concept, the third embodiment of the present invention further provides a computer device, as Figure 9 shown, including a memory 304, a processor 302, and a computer program stored on the memory 304 and executable on the processor 302. When the processor 302 executes the program, it implements the steps of any one of the methods in the above-mentioned thermal simulation method of the flexible-rigid printed circuit board.

[0098] Among them, in Figure 9 it, the bus architecture (represented by bus 300), the bus 300 can include any number of interconnected buses and bridges. The bus 300 links together various circuits including one or more processors represented by the processor 302 and the memory represented by the memory 304. The bus 300 can also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art. Therefore, they will not be further described herein. The bus interface 306 provides an interface between the bus 300 and the receiver 301 and the transmitter 303. The receiver 301 and the transmitter 303 can be the same element, that is, a transceiver, which provides a unit for communicating with various other devices on the transmission medium. The processor 302 is responsible for managing the bus 300 and general processing, while the memory 304 can be used to store data used by the processor 302 when performing operations.

[0099] Embodiment 4

[0100] Based on the same inventive concept, the fourth embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the steps of any one of the methods in the thermal simulation method of the flexible-rigid printed circuit board described in the foregoing Embodiment 1.

[0101] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0102] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0103] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0104] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0105] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0106] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A thermal simulation method for a rigid-flex printed circuit board, characterized in that Including: Obtaining the flexible board parameters of the first rigid-flex board simulation model, where the simulation model is a preset model of the first rigid-flex board in a bent state, and the flexible board parameters are the parameters of the flexible board of the first rigid-flex board; According to the simulation model and the flexible board parameters, obtaining the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient; According to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient, adjusting the initial isotropic thermal conductivity coefficient of the simulation model to obtain a target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies a temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

2. The method according to claim 1, characterized in that, The flexible board includes N copper foil layers, where N is a positive integer not less than 1. Obtaining the flexible board parameters includes: Obtaining the copper content rate of each copper foil layer in the N copper foil layers and the stacked structure thickness of the flexible board, where the stacked structure thickness is the thickness of the flexible board in the bent state; The obtaining the anisotropic thermal conductivity coefficient of the simulation model according to the simulation model and the flexible board parameters includes: Obtaining the anisotropic thermal conductivity coefficient according to the simulation model, the copper content rate of each copper foil layer, and the stacked structure thickness.

3. The method according to claim 2, characterized in that, The obtaining the copper content rate of each copper foil layer in the N copper foil layers includes: Obtaining the copper trace distribution area of each copper foil layer and the total area of the flexible board; According to the copper trace distribution area of each copper foil layer and the total area, obtaining the copper content rate of each copper foil layer.

4. The method according to claim 1, characterized in that The adjusting the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain a target isotropic thermal conductivity coefficient includes: Adjusting the initial isotropic thermal conductivity coefficient according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain an adjusted isotropic thermal conductivity coefficient; If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is not greater than a temperature difference threshold, then determining the adjusted isotropic thermal conductivity coefficient as the target isotropic thermal conductivity coefficient.

5. The method according to claim 4, wherein After obtaining the adjusted isotropic thermal conductivity coefficient, it further includes: If the temperature difference between the junction temperature of the simulation model corresponding to the adjusted isotropic thermal conductivity coefficient and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient is greater than the temperature difference threshold, then continue to adjust the adjusted isotropic thermal conductivity coefficient until the target isotropic thermal conductivity coefficient is obtained.

6. The method according to claim 1, wherein After obtaining the target isotropic thermal conductivity coefficient, it further includes: Obtaining the anisotropic thermal conductivity coefficient of the second rigid-flex board simulation model, where the number of copper foil layers of the flexible board of the second rigid-flex board is the same as that of the flexible board of the first rigid-flex board; Obtain the isotropic thermal conductivity coefficient of the second flexible-rigid printed circuit board simulation model according to the ratio of the anisotropic thermal conductivity coefficient of the first flexible-rigid printed circuit board simulation model to the target isotropic thermal conductivity coefficient, and the anisotropic thermal conductivity coefficient of the second flexible-rigid printed circuit board simulation model.

7. The method according to claim 1, wherein The simulation model is a splicing model composed of a flexible board model and a rigid board model of the first flexible-rigid printed circuit board.

8. A thermal simulation device for a rigid-flexible printed circuit board, characterized in that, It includes: A first acquisition module, configured to acquire the flexible board parameters of the first flexible-rigid printed circuit board simulation model, where the simulation model is a preset model of the first flexible-rigid printed circuit board in a bent state, and the flexible board parameters are the parameters of the flexible board of the first flexible-rigid printed circuit board; A second acquisition module, configured to obtain the anisotropic thermal conductivity coefficient of the simulation model and the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient according to the simulation model and the flexible board parameters; An adjustment module, configured to adjust the initial isotropic thermal conductivity coefficient of the simulation model according to the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient to obtain a target isotropic thermal conductivity coefficient, where the junction temperature of the simulation model corresponding to the target isotropic thermal conductivity coefficient satisfies a temperature setting condition with the junction temperature of the simulation model corresponding to the anisotropic thermal conductivity coefficient.

9. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method steps described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method steps described in any one of claims 1-7.

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