Printed circuit board laminated structure of driving mode selection controller and design method thereof
By using a 4-layer stacked structure design, the problem of resource waste in the traditional PCB layout of driving mode selection controllers is solved, achieving cost savings and product compactness, enhancing product competitiveness, and meeting the needs of the modern vehicle electronics industry.
Patent Information
- Application Number
- CN202511788892.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-30
- Publication Date
- 2026-02-27
AI Technical Summary
Traditional driving mode selection controller PCB layout designs suffer from resource waste and insufficient space utilization, resulting in high manufacturing costs and non-compact products, making it difficult to meet the modern vehicle electronics industry's demand for efficient and compact solutions.
The design employs a four-layer stacked structure, including a top layer, a ground layer, a power signal layer, and a bottom layer. The top layer houses the circuitry, the ground layer provides a reference ground signal, the power signal layer contains the critical power planes and signal traces, and the bottom layer contains the general power planes and general signal traces. Signal and power transmission is achieved through via connections, and electromagnetic interference is isolated using the ground layer.
It effectively reduces the number of printed circuit board layers, saves development costs, enhances the market competitiveness of products, and meets the needs of the modern vehicle electronics industry for efficient and compact solutions.
Smart Images
Figure CN121586154A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of printed circuit board stack-up structure design technology, and specifically to a printed circuit board stack-up structure for a driving mode selection controller and its design method. Background Technology
[0002] Traditional driving mode selection controllers typically employ a 6-layer PCB design with a single-sided component layout. This design ensures ample routing space for power, ground, and signal layers, thereby providing high reliability in terms of electrical performance.
[0003] However, this layout also leads to over-design, meaning resources are not fully utilized and space is wasted. This not only increases manufacturing costs and material consumption but may also result in a less compact product structure, affecting overall efficiency. Furthermore, excessive design redundancy often fails to flexibly adapt to market demands for lightweighting and cost control.
[0004] Therefore, this over-design ultimately weakens the product's market competitiveness, making it difficult to balance cost-effectiveness and performance optimization, and failing to meet the growing demands of the modern vehicle electronics industry for efficient and compact solutions. Summary of the Invention
[0005] In view of this, embodiments of the present invention provide a printed circuit board stack structure for a driving mode selection controller and a design method thereof.
[0006] The first aspect of the present invention provides a printed circuit board stack structure for a driving mode selection controller, wherein the stack structure comprises, from top to bottom, a top layer, a ground layer, a power signal layer and a bottom layer; The top layer is used to deploy circuit devices; the ground layer is used to provide a reference ground signal; the power signal layer is used to deploy critical power planes and critical signal traces; the bottom layer is used to deploy ordinary power planes and ordinary signal traces; the ground pins of the circuit devices in the top layer are connected to the ground layer through vias, and the signal pins and power pins of the circuit devices are connected to the power signal layer and the bottom layer through vias.
[0007] Furthermore, the circuit devices deployed in the top layer specifically include: a power input module and a power chip module, an MCU module, a nuclear power module, a high-side and low-side drive module, a CAN transceiver module, a LIN transceiver module, a digital input module, and a FLASH module; The top layer has a copper thickness of 0.5 oz plus an electroplated layer.
[0008] Furthermore, the power input module is positioned close to the power input pin of the external connector; the power input module is used to receive a 12V external power input, and after protecting, filtering, and stabilizing the power input, it is transmitted to the power chip module. The power chip module includes a DC-DC module and an LDO module; the DC-DC module is located near the MCU module and is used to provide 3.3V power supply to the nuclear power module, the MCU module and the CAN transceiver module; the LDO module is located near the LIN transceiver module and is used to provide 5V power supply to the LIN transceiver module. The CAN transceiver module is located near the CAN signal transmission port of the external connector; it is used to receive driving mode switching signal input from the vehicle CAN bus, convert it into a serial signal, and then transmit it to the MCU module. The LIN transceiver module is used to receive LIN signal input from the vehicle main controller, convert it into a serial signal, and then transmit it to the MCU module. The digital input module is located near the digital signal transmission port of the external connector; it is used to receive digital signal input, convert it into a level signal, and then transmit it to the MCU module. The FLASH module is located close to the MCU module and is connected to the MCU module via the SPI bus for storing data; The MCU module is located at the center of the top layer and is used to generate control signals based on the data transmitted by the CAN transceiver, the LIN transceiver and the digital input module and send them to the high and low side drive module. The nuclear power module is arranged around the MCU module to provide the MCU module with 0.8V power and sampling voltage. The high and low side drive modules are located near the drive output pins of the external connector; the high and low side drive modules include a high side drive module and a low side drive module, which are used to generate drive signals according to the control signals transmitted by the MCU module and output them to the vehicle actuators to change the vehicle driving mode.
[0009] Furthermore, the grounding layer is composed of a continuous copper plane with a copper thickness of 1 oz; the grounding layer is also used to isolate electromagnetic interference between the top layer and the power signal layer.
[0010] Furthermore, the key power planes in the power signal layer include a 3.3V voltage plane, a 5V voltage plane, and a nuclear power sampling plane; The 3.3V voltage plane takes the top-level DC-DC module as input and the nuclear power module and FLASH module as output, and is used to provide 3.3V voltage transmission between the DC-DC module and the nuclear power module and FLASH module; The nuclear power sampling plane takes the top-level nuclear power module as input and the MCU module as output, and is used to provide sampling voltage transmission between the nuclear power module and the MCU module; The 5V voltage plane takes the top-level LDO module as input and the CAN transceiver and LIN transceiver as output, and is used to provide 5V voltage transmission between the LDO module and the CAN transceiver and LIN transceiver. The key signal traces in the power signal layer include SPI traces, MCU core power traces, and MCU reset traces. The SPI traces include CS signal traces, CLK signal traces, MISO signal traces, and MOSI signal traces; the CS signal traces, CLK signal traces, and MOSI signal traces take the top-level MCU module as input and the FLASH module as output; the MISO signal trace takes the FLASH module as input and the MCU module as output. The MCU nuclear power circuitry uses nuclear power as input and the MCU module as output. The MCU reset trace takes the connector as input and the MCU module as output. The critical signal traces are used to provide signal transmission lines between inputs and outputs.
[0011] Furthermore, the critical power plane and critical signal traces are separated by a keep-out area to reduce the generation of coupling noise; the power signal layer uses the ground plane as a reference plane; the copper thickness of the power signal layer is 1 oz.
[0012] Furthermore, the underlying general power plane includes a 12V voltage plane and a 3.3V voltage plane; the 12V voltage plane takes the top power input as input and the DC-DC module, LDO module and high-side drive module as output, and is used to provide 12V voltage transmission between the power input and the DC-DC module, LDO module and high-side drive module. The 3.3V voltage plane takes the top-level DC-DC module as input and the nuclear power module and FLASH module as output, and is used to provide 3.3V voltage transmission between the DC-DC module and the nuclear power module and FLASH module; The underlying general signal traces include other signal traces between the top-level circuit devices, excluding critical signal traces, and are used to provide signal transmission lines between circuit devices.
[0013] Furthermore, the copper thickness of the bottom layer is 1 oz.
[0014] A second aspect of this invention discloses a design method for a printed circuit board stack-up structure, used to design the aforementioned printed circuit board stack-up structure of a driving mode selection controller, comprising the following steps: Pre-layout of printed circuit boards; Confirm the number of device layers, power layers, signal layers, and ground layers in the printed circuit board; Construct a printed circuit board stack-up structure.
[0015] Furthermore, in the step of confirming the number of device layers, power layers, signal layers, and ground layers in the printed circuit board, confirming the number of device layers specifically includes the following steps: The number of device layers in the printed circuit board is determined based on the volume of the circuit components. To determine the number of grounding layers, the following steps are required: The number of ground layers is determined based on the number of device layers; To confirm the number of power layers, the specific steps include: Identify the power network required for the printed circuit board components. When the number of power networks is 1, the number of power layers is confirmed to be 1. When the number of power networks is not 1, confirm the overlapping area when the power networks are deployed on the same layer, and the current magnitude of each power network; When the power network is deployed on the same layer without overlapping, the number of power layers is determined according to the current magnitude. When the power networks are deployed on the same layer and overlap, the number of power layers is increased according to the overlapping area and the current magnitude. Determining the number of signal layers involves the following steps: The signal transmission between printed circuit board components is divided into critical signals and ordinary signals; Critical signals and ordinary signals are transmitted on different power layers. If there are fewer than two power layers, add at least one signal layer. Determine whether critical signals and ordinary signals can be routed on their corresponding power layers. If routing is not possible, increase the number of signal layers.
[0016] The embodiments of the present invention have the following beneficial effects: The printed circuit board stack-up structure and design method of the driving mode selection controller provided by the present invention, by planning the stack-up of power layer, signal layer and ground layer, the signal lines are mixed and routed on the power layer, and the ground layer is used to provide a reference plane to the device layer and power signal layer, which effectively reduces the number of printed circuit board stack-up layers and can save development costs.
[0017] Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description or may be learned by practice of the invention. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a schematic diagram of the top layer layout of the printed circuit board stack structure of a driving mode selection controller according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the power signal layer layout of the printed circuit board stack-up structure of a driving mode selection controller according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the bottom layer layout of the printed circuit board stack structure of a driving mode selection controller according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the basic flow of a design method for a printed circuit board stack-up structure according to an embodiment of the present invention; Figure 5 This is a power layer design flowchart of a printed circuit board stack-up structure design method according to an embodiment of the present invention; Figure 6 This is a flowchart illustrating the signal layer design method for a printed circuit board stack-up structure according to an embodiment of the present invention. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0021] Traditional driving mode selection controller PCB layout and routing uses a 6-layer circuit board and single-sided component layout structure. There is sufficient routing space for power, ground and signal, and some space is left over. This is an over-design phenomenon, which is not conducive to improving the product's market competitiveness.
[0022] The existing driving mode selection controller design is a 6-layer board, and its stack-up design and signal power layer planning are as follows: L01 - Top layer; 1oz copper thickness + electroplating layer; used for layout of all components on the board.
[0023] L02 - Formation; copper thickness 1 oz; used as a reference ground plane.
[0024] L03 - Signal layer; copper thickness 1 oz; used for setting up horizontal wiring signals.
[0025] L04 - Signal layer; copper thickness 1oz; used for setting up vertical wiring signals.
[0026] L05 - Signal layer; copper thickness 1oz; used for setting up other signal routing.
[0027] L06 - Bottom layer; 1oz copper thickness + electroplating layer; used for power supply.
[0028] Among them, only the TOP layer has component layout, the 2nd layer is a complete ground layer, the 3rd layer has horizontally routed signal traces, the 4th layer has vertically routed signal traces, the 5th layer has power supply and a small number of signals, and the BOT layer has power supply.
[0029] In view of the shortcomings of existing stack-up designs, the first embodiment of the present invention provides a printed circuit board stack-up structure for a driving mode selection controller, wherein the stack-up structure includes, from top to bottom, a top layer, a ground layer, a power signal layer and a bottom layer. The top layer is used to deploy circuit devices; the ground layer is used to provide a reference ground signal; the power signal layer is used to deploy critical power planes and critical signal traces; and the bottom layer is used to deploy ordinary power planes and ordinary signal traces. The ground pins of the circuit devices in the top layer are connected to the ground layer through vias, and the signal pins and power pins of the circuit devices are connected to the power signal layer and the bottom layer through vias.
[0030] The stacked structure provided in this embodiment of the invention, through the stacking planning of power layer, signal layer and ground layer, mixes the signal lines on the power layer and uses the ground layer to provide a reference plane to the device layer and power signal layer, effectively reducing the number of layers in the printed circuit board stack and saving development costs.
[0031] The stacked structure of this embodiment will be described below: Top level: such as Figure 1 As shown, in this embodiment of the invention, the top layer serves as the main component layout layer, responsible for placing all electronic components (such as power input modules, MCUs, CAN transceivers, etc.), performing signal input / output interface functions, preliminary signal processing, and power distribution. The top layer has a copper thickness of 0.5oz plus an electroplated layer, and the circuit components specifically laid out include: power input modules and power chip modules, MCU modules, core power modules, high and low side driver modules, CAN transceiver modules, LIN transceiver modules, digital input modules, and FLASH modules.
[0032] The power input module has its power input pin located near the external connector. The power input module receives a 12V external power input, protects, filters, and stabilizes the power input before transmitting it to the power chip module.
[0033] The power chip module includes a DC-DC module and an LDO module. The DC-DC module is located near the MCU module and is used to provide 3.3V power to the nuclear power module, MCU module and CAN transceiver module. The LDO module is located near the LIN transceiver module and is used to provide 5V power to the LIN transceiver module.
[0034] The CAN transceiver module has a CAN signal transmission port located near the external connector; it is used to receive driving mode switching signal input from the vehicle's CAN bus, convert it into a serial signal, and then transmit it to the MCU module.
[0035] The LIN transceiver module is used to receive LIN signal input from the vehicle's main controller, convert it into a serial signal, and then transmit it to the MCU module.
[0036] The digital input module is located near the digital signal transmission port of the external connector; it is used to receive digital signal input, convert it into a level signal, and then transmit it to the MCU module.
[0037] The FLASH module is located close to the MCU module and is connected to the MCU module via the SPI bus for storing data.
[0038] The MCU module is located at the center of the top layer and is used to generate control signals based on the data transmitted by the CAN transceiver, LIN transceiver and digital input module, and send them to the high and low side drive modules.
[0039] The nuclear power module is positioned around the MCU module to provide the MCU module with 0.8V power and sampling voltage.
[0040] The high and low side drive modules are located near the drive output pins of the external connector; the high and low side drive modules include a high side drive module and a low side drive module, which are used to generate drive signals according to the control signals transmitted by the MCU module and output them to the vehicle actuators to change the vehicle driving mode.
[0041] The top-level internal structure is a highly integrated layout, with module placement optimized for functional requirements and signal integrity. Through a single-sided layout and rational module arrangement, effective integration with the inner layers is achieved, thereby reducing the number of printed circuit board layers.
[0042] Ground plane: In this embodiment of the invention, the ground plane is composed of a continuous copper plane with a thickness of 1 oz. The ground plane is a continuous copper plane without any segmentation or patterning design. This means that the entire layer is completely covered by copper foil, forming a uniform ground potential area. This "complete ground plane" design simplifies layout, reduces impedance, and improves signal integrity. Simultaneously, the ground plane serves as a reference plane, providing a stable ground potential for top-layer devices and traces; isolating electromagnetic interference (EMI) generated by top-layer switching power supplies and other modules to ensure signal quality; and dissipating noise through low-impedance paths to meet EMC (electromagnetic compatibility) standards. Furthermore, as a large-area copper plane, the ground plane aids in heat dissipation, especially when high-current devices on the top layer (such as high- and low-side drive modules) generate heat; the ground plane can conduct heat to the entire printed circuit board through vias for heat dissipation.
[0043] Power signal layer: such as Figure 2 As shown, in this embodiment of the invention, the key power planes in the power signal layer include a 3.3V voltage plane, a 5V voltage plane, and a nuclear power sampling plane.
[0044] The 3.3V voltage plane takes the top-level DC-DC module as input and the nuclear power module and FLASH module as output, and is used to provide 3.3V voltage transmission between the DC-DC module and the nuclear power module and FLASH module.
[0045] The nuclear power sampling plane takes the top-level nuclear power module as input and the MCU module as output, and is used to provide sampling voltage transmission between the nuclear power module and the MCU module.
[0046] The 5V voltage plane takes the top-level LDO module as input and the CAN transceiver and LIN transceiver as output, and is used to provide 5V voltage transmission between the LDO module and the CAN transceiver and LIN transceiver.
[0047] On the other hand, key signal traces in the power signal layer include SPI traces, MCU core power traces, and MCU reset traces.
[0048] The SPI traces include CS signal traces, CLK signal traces, MISO signal traces, and MOSI signal traces. The CS, CLK, and MOSI signal traces take the top-level MCU module as input and the FLASH module as output; the MISO signal trace takes the FLASH module as input and the MCU module as output. The MCU nuclear power circuitry uses nuclear power as input and the MCU module as output. The MCU reset trace uses the connector as input and the MCU module as output. Critical signal traces are used to provide signal transmission lines between inputs and outputs.
[0049] In this embodiment of the invention, the critical power plane and critical signal traces are separated by a keep-out area to reduce the generation of coupling noise; the power signal layer uses the ground plane as a reference plane; the copper thickness of the power signal layer is 1 oz. By routing the critical signals within the power layer and using the adjacent ground plane as shielding and reference, the quality of the critical signals is ensured to remain unaffected even with high integration and a reduced number of layers.
[0050] bottom layer: such as Figure 3 As shown, the bottom-level general power plane includes a 12V voltage plane and a 3.3V voltage plane; the 12V voltage plane takes the top-level power input as input and the DC-DC module, LDO module and high-side driver module as output, and is used to provide 12V voltage transmission between the power input and the DC-DC module, LDO module and high-side driver module. The 3.3V voltage plane takes the top-level DC-DC module as input and the nuclear power module and FLASH module as output, and is used to provide 3.3V voltage transmission between the DC-DC module and the nuclear power module and FLASH module.
[0051] The bottom layer of ordinary signal traces includes all signal traces between the top layer circuit devices except for critical signal traces, and is used to provide signal transmission lines between circuit devices.
[0052] In this embodiment of the invention, the copper thickness of the bottom layer is 1 oz. The primary reference plane for signal traces on the bottom layer is the ground plane. However, since the signals are ordinary signals, their requirements for the reference plane are not as stringent as those for critical signals. Therefore, it is acceptable even if the return path passes through the power plane. On the other hand, the power signal layer can also be used as a secondary or local reference plane.
[0053] The stacked design structure provided by this invention places the source and destination of all signals on the same side. This means that all signal outgoing and returning lines only need to be routed between the top layer and the adjacent inner layer, without needing to penetrate the entire printed circuit board to the other side, reducing the need for multiple signal layers. This invention also effectively isolates high-frequency noise generated by the top-layer switching power supply module (such as a DC-DC module) through a ground plane, preventing it from interfering with sensitive signals on the power signal layer below. This makes it possible to route critical signals above the power layer; through hierarchical processing, all signals are routed within only two mixed layers, eliminating the need for additional dedicated signal layers. In summary, the stacked design structure provided by this invention successfully reduces the number of PCB layers from 6 to 4 while ensuring product performance (meeting 85°C ambient temperature and EMC standards), significantly reducing costs and enhancing product competitiveness.
[0054] The second embodiment of the present invention provides a design method for a printed circuit board stack-up structure, used to design the printed circuit board stack-up structure of the driving mode selection controller of the first embodiment, such as... Figure 4 As shown, it includes the following steps: S1. Pre-layout of the printed circuit board; S2. Confirm the number of device layers, power layers, signal layers, and ground layers in the printed circuit board; S3. Construct a printed circuit board stack-up structure.
[0055] In a preferred embodiment, step S2, which confirms the number of device layers, power layers, signal layers, and ground layers in the printed circuit board, includes the following steps: S2-a. Confirm the number of device layers, specifically including the following steps: The number of device layers in a printed circuit board is determined based on the size of the circuit components.
[0056] In this embodiment of the invention, it is necessary to calculate the total volume and distribution density of all circuit components. For example, if the total volume of the components is large or their distribution is dense, and a single layer cannot accommodate them, the number of component layers needs to be increased. Specifically, the component footprint can be calculated using CAD tools and evaluated in conjunction with PCB thickness and interlayer gaps.
[0057] S2-b. Confirm the number of grounding layers, specifically including the following steps: The number of ground planes is determined based on the number of device layers.
[0058] The number of grounding layers is usually positively correlated with the number of device layers. The embodiments of the present invention simplify the design through simple association, ensure grounding integrity, and improve circuit stability.
[0059] S2-c. Confirm the number of power layers, such as Figure 5 As shown, the specific steps include: Identify the power network required for the printed circuit board components. When the number of power networks is 1, the number of power layers is confirmed to be 1. When the number of power networks is not 1, confirm the overlapping area when the power networks are deployed on the same layer, and the current magnitude of each power network. When the power supply network is deployed on the same layer without overlap, the number of power supply layers is determined according to the current magnitude. When power networks overlap on the same layer, the number of power layers is increased according to the overlapping area and the current magnitude.
[0060] In this embodiment of the invention, the power layer configuration is dynamically optimized by analyzing overlap and current parameters to overcome power integrity issues.
[0061] S2-d. Confirm the number of signal layers, such as Figure 6 As shown, the specific steps include: The signal transmission between printed circuit board components is divided into critical signals and ordinary signals; Critical signals and ordinary signals are transmitted on different power layers. If there are fewer than two power layers, add at least one signal layer. Determine whether critical signals and ordinary signals can be routed on their corresponding power layers. If routing is not possible, increase the number of signal layers.
[0062] In this embodiment of the invention, signal classification and wiring verification optimize signal integrity and reduce crosstalk and delay.
[0063] Those skilled in the art will understand that modules in the device of the embodiments of the present invention can be adaptively modified and placed in one or more devices different from those embodiments. Modules, units, or components in the embodiments of the present invention can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the corresponding claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the corresponding claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.
[0064] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.
[0065] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0066] Furthermore, the terms "first," "second," etc., used in the embodiments of this invention are for descriptive purposes only and should not be construed as indicating or implying relative importance, or implicitly specifying the number of technical features indicated in this embodiment. Therefore, features defined with terms such as "first" and "second" in the embodiments of this invention can explicitly or implicitly indicate that the embodiment includes at least one of those features. In the description of this invention, the word "multiple" means at least two or more, such as two, three, four, etc., unless otherwise explicitly specified in the embodiments.
[0067] In embodiments of the present invention, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, components, features, and elements with the same names in different embodiments of the present invention may have the same meaning or different meanings, the specific meaning of which must be determined by its interpretation in that specific embodiment or further in conjunction with the context of that specific embodiment.
[0068] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention. Other embodiments of the present invention will readily conceive of by considering the specification and practicing the invention. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims.
Claims
1. A printed circuit board stack-up structure for a driving mode selection controller, characterized in that, The stacked structure, from top to bottom, includes a top layer, a ground layer, a power signal layer, and a bottom layer. The top layer is used to deploy circuit devices; the ground layer is used to provide a reference ground signal; the power signal layer is used to deploy critical power planes and critical signal traces; the bottom layer is used to deploy ordinary power planes and ordinary signal traces; the ground pins of the circuit devices in the top layer are connected to the ground layer through vias, and the signal pins and power pins of the circuit devices are connected to the power signal layer and the bottom layer through vias.
2. The printed circuit board stack-up structure of a driving mode selection controller according to claim 1, characterized in that, The circuit devices arranged in the top layer specifically include: power input module and power chip module, MCU module, nuclear power module, high and low side drive module, CAN transceiver module, LIN transceiver module, digital input module and FLASH module. The top layer has a copper thickness of 0.5 oz plus an electroplated layer.
3. The printed circuit board stack-up structure of a driving mode selection controller according to claim 2, characterized in that, The power input module is located near the power input pin of the external connector; the power input module is used to receive a 12V external power input, and after protecting, filtering and stabilizing the power input, it is transmitted to the power chip module. The power chip module includes a DC-DC module and an LDO module; the DC-DC module is located near the MCU module and is used to provide 3.3V power supply to the nuclear power module, the MCU module and the CAN transceiver module; the LDO module is located near the LIN transceiver module and is used to provide 5V power supply to the LIN transceiver module. The CAN transceiver module is located near the CAN signal transmission port of the external connector; it is used to receive driving mode switching signal input from the vehicle CAN bus, convert it into a serial signal, and then transmit it to the MCU module. The LIN transceiver module is used to receive LIN signal input from the vehicle main controller, convert it into a serial signal, and then transmit it to the MCU module. The digital input module is located near the digital signal transmission port of the external connector; it is used to receive digital signal input, convert it into a level signal, and then transmit it to the MCU module. The FLASH module is located close to the MCU module and is connected to the MCU module via the SPI bus for storing data; The MCU module is located at the center of the top layer and is used to generate control signals based on the data transmitted by the CAN transceiver, the LIN transceiver and the digital input module and send them to the high and low side drive module. The nuclear power module is arranged around the MCU module to provide the MCU module with 0.8V power and sampling voltage. The high and low side drive modules are located near the drive output pins of the external connector; the high and low side drive modules include a high side drive module and a low side drive module, which are used to generate drive signals according to the control signals transmitted by the MCU module and output them to the vehicle actuators to change the vehicle driving mode.
4. The printed circuit board stack-up structure of a driving mode selection controller according to claim 1, characterized in that, The grounding layer is composed of a continuous copper plane with a copper thickness of 1 oz; the grounding layer is also used to isolate electromagnetic interference between the top layer and the power signal layer.
5. The printed circuit board stack-up structure of a driving mode selection controller according to claim 2, characterized in that, The key power planes in the power signal layer include the 3.3V voltage plane, the 5V voltage plane, and the nuclear power sampling plane; The 3.3V voltage plane takes the top-level DC-DC module as input and the nuclear power module and FLASH module as output, and is used to provide 3.3V voltage transmission between the DC-DC module and the nuclear power module and FLASH module; The nuclear power sampling plane takes the top-level nuclear power module as input and the MCU module as output, and is used to provide sampling voltage transmission between the nuclear power module and the MCU module; The 5V voltage plane takes the top-level LDO module as input and the CAN transceiver and LIN transceiver as output, and is used to provide 5V voltage transmission between the LDO module and the CAN transceiver and LIN transceiver. The key signal traces in the power signal layer include SPI traces, MCU core power traces, and MCU reset traces. The SPI traces include CS signal traces, CLK signal traces, MISO signal traces, and MOSI signal traces; the CS signal traces, CLK signal traces, and MOSI signal traces take the top-level MCU module as input and the FLASH module as output; the MISO signal trace takes the FLASH module as input and the MCU module as output. The MCU nuclear power circuitry uses nuclear power as input and the MCU module as output. The MCU reset trace takes the connector as input and the MCU module as output. The critical signal traces are used to provide signal transmission lines between inputs and outputs.
6. The printed circuit board stack-up structure of a driving mode selection controller according to claim 5, characterized in that, The critical power plane and critical signal traces are separated by a keep-out zone to reduce the generation of coupling noise; the power signal layer uses the ground plane as a reference plane; the copper thickness of the power signal layer is 1 oz.
7. The printed circuit board stack-up structure of a driving mode selection controller according to claim 2, characterized in that, The underlying general power plane includes a 12V voltage plane and a 3.3V voltage plane; the 12V voltage plane takes the top power input as input and the DC-DC module, LDO module and high-side drive module as output, and is used to provide 12V voltage transmission between the power input and the DC-DC module, LDO module and high-side drive module. The 3.3V voltage plane takes the top-level DC-DC module as input and the nuclear power module and FLASH module as output, and is used to provide 3.3V voltage transmission between the DC-DC module and the nuclear power module and FLASH module; The underlying general signal traces include other signal traces between the top-level circuit devices, excluding critical signal traces, and are used to provide signal transmission lines between circuit devices.
8. The printed circuit board stack-up structure of a driving mode selection controller according to claim 7, characterized in that, The copper thickness of the bottom layer is 1 oz.
9. A method for designing a printed circuit board stack-up structure, used to design the printed circuit board stack-up structure of a driving mode selection controller as described in any one of claims 1-8, characterized in that, Includes the following steps: Pre-layout of printed circuit boards; Confirm the number of device layers, power layers, signal layers, and ground layers in the printed circuit board; Construct a printed circuit board stack-up structure.
10. The design method for a printed circuit board stack-up structure according to claim 9, characterized in that, The step of confirming the number of device layers, power layers, signal layers, and ground layers in the printed circuit board, specifically includes the following steps: The number of device layers in the printed circuit board is determined based on the volume of the circuit components. To determine the number of grounding layers, the following steps are required: The number of ground layers is determined based on the number of device layers; To confirm the number of power layers, the specific steps include: Identify the power network required for the printed circuit board components. When the number of power networks is 1, the number of power layers is confirmed to be 1. When the number of power networks is not 1, confirm the overlapping area when the power networks are deployed on the same layer, and the current magnitude of each power network; When the power network is deployed on the same layer without overlapping, the number of power layers is determined according to the current magnitude. When the power networks are deployed on the same layer and overlap, the number of power layers is increased according to the overlapping area and the current magnitude. Determining the number of signal layers involves the following steps: The signal transmission between printed circuit board components is divided into critical signals and ordinary signals; Critical signals and ordinary signals are transmitted on different power layers. If there are fewer than two power layers, add at least one signal layer. Determine whether critical signals and ordinary signals can be routed on their corresponding power layers. If routing is not possible, increase the number of signal layers.