Ground plane structure of PCB and test board

Abstract

The application provides a ground plane structure of a PCB circuit board and a test board card. The ground plane structure comprises a first region and a second region, and the first region is connected with the second region at a single point. The first region serves as a reference ground for first-type ground pins of a plurality of channel devices, and the second region serves as a reference ground for second-type ground pins of the plurality of channel devices. The reference ground potential of the first-type ground pins is associated with output signals of the plurality of channel devices, and the reference ground potential of the second-type ground pins is not associated with the output signals of the plurality of channel devices. The ground function is divided into the first region and the second region, so that the influence of a ground potential difference caused by a large ground current of the second-type ground pins on output accuracy is greatly reduced, and the output accuracy of each channel device is improved.

Description

Technical Field

[0001] This application relates to the field of circuit design, and in particular to a ground plane structure of a PCB circuit board and a test board. Background Technology

[0002] Printed circuit boards (PCBs) are an important component of electronic products, providing the physical support and signal transmission for electronic products. They provide electrical connections between circuit elements and devices.

[0003] Existing PCBs typically feature multiple channel devices with a single ground plane that doesn't differentiate between ground zones. The entire board shares a single reference source and uses only one ground zone. When a channel device outputs a large current, significant current flows through the ground copper layer. Since the ground copper layer itself has impedance, current flowing through this impedance creates a voltage drop, resulting in different reference ground potentials at different points on the PCB. Because each channel device references the same reference source, the output accuracy of channel devices farther from the reference source is significantly affected. Utility Model Content

[0004] Therefore, it is necessary to provide a ground plane structure for a PCB circuit board and a test board to address the aforementioned technical problems.

[0005] In a first aspect, embodiments of this application propose a ground plane structure for a PCB circuit board, the PCB circuit board including multiple channel devices, the ground plane structure including a first ground region and a second ground region, the first ground region and the second ground region being connected at a single point; Wherein, the first ground area serves as the reference ground for the first type of ground pin of the plurality of channel devices, and the second ground area serves as the reference ground for the second type of ground pin of the plurality of channel devices. The reference ground potential of the first type of ground pin is associated with the output signal of the plurality of channel devices, and the reference ground potential of the second type of ground pin is not associated with the output signal of the plurality of channel devices.

[0006] In some embodiments, the first type of ground pin of the plurality of channel devices includes an analog ground pin; The analog ground pins of the multiple channel devices are all connected to the first ground area.

[0007] In some embodiments, the second type of ground pins of the plurality of channel devices includes a digital ground pin and a power ground pin; The digital ground pins and power ground pins of the multiple channel devices are all connected to the second ground area.

[0008] In some embodiments, the PCB circuit board further includes a reference source, the reference source including an analog ground pin, the analog ground pin of the reference source being connected to the first ground area.

[0009] In some embodiments, the first region and the second region are located on the same layer of the PCB circuit board, and the first region and the second region are connected by traces.

[0010] In some embodiments, the first region and the second region are located on different layers of the PCB circuit board, and the first region and the second region are connected by any one of the vias, ferrite beads or zero-ohm resistors of the PCB circuit board.

[0011] In some embodiments, the ground plane structure further includes a third ground region, which is single-point connected to the second ground region. The third ground region serves as a reference ground for the third type of ground pin of the plurality of channel devices, and the reference ground potential of the third type of ground pin is not associated with the output signal of the plurality of channel devices.

[0012] In some embodiments, the second type of ground pin of the plurality of channel devices includes a power ground pin connected to the second ground area; the third type of ground pin of the plurality of channel devices includes a digital ground pin connected to the third ground area.

[0013] In some embodiments, the second region and the third region are located on the same layer of the PCB circuit board, and the second region and the third region are connected by traces; or, The second region and the third region are located on different layers of the PCB circuit board, and the second region and the third region are connected by any one of the vias, ferrite beads or zero-ohm resistors of the PCB circuit board.

[0014] Secondly, embodiments of this application propose a test board, including a reference source, multiple channel devices, and a PCB circuit board as described in the first aspect.

[0015] The aforementioned ground plane structure and test board offer the following technical advantages: By dividing the PCB into a first ground region and a second ground region, with a single-point connection between them, the first ground region serves as the reference ground for the first type of ground pins of multiple channel devices, while the second ground region serves as the reference ground for the second type of ground pins of multiple channel devices. The reference ground voltage of the first type of ground pins is correlated with the output signals of the multiple channel devices, while the reference ground voltage of the second type of ground pins is not correlated with the output signals of the multiple channel devices. Since the ground current in the first ground region where the first type of ground pins are located is much smaller than the ground current in the second ground region where the second type of ground pins are located, the potential difference between the first type of ground pins is smaller. By functionally dividing the ground into a first ground region and a second ground region, the impact of the potential difference caused by the larger ground current of the second type of ground pins on output accuracy is greatly reduced, thereby improving the output accuracy of each channel device. Attached Figure Description

[0016] Figure 1 A schematic diagram of the ground plane structure of the PCB circuit board in the first example embodiment provided in this application; Figure 2 This is an equivalent schematic diagram of the ground plane structure of the PCB circuit board in the first example embodiment provided in this application; Figure 3 This is a schematic diagram of the ground plane structure of the PCB circuit board in the second example embodiment provided in this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the application is described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the application. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application. Furthermore, it is understood that although the efforts made in such a development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, modifications to design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as insufficient disclosure of the content of this application.

[0018] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0019] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms “a,” “an,” “an,” “the,” and similar words used in this application do not indicate quantity limitation and may indicate singular or plural. The terms “comprising,” “including,” “having,” and any variations thereof used in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units not listed, or may include other steps or units inherent to these processes, methods, products, or devices. The terms “connected,” “linked,” “coupled,” and similar words used in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. “Multiple” used in this application means two or more. “And / or” describes the relationship between related objects, indicating that three relationships may exist; for example, “A and / or B” can represent: A alone, A and B simultaneously, and B alone. The terms “first,” “second,” “third,” etc., used in this application are merely to distinguish similar objects and do not represent a specific ordering of the objects.

[0020] Figure 1 This is a schematic diagram of the ground plane structure of the PCB circuit board in the first example embodiment provided in this application. Figure 1 As shown, the PCB circuit board includes multiple channel devices, and the ground plane structure includes a first ground region and a second ground region, which are connected at a single point.

[0021] The first ground region serves as the reference ground for the first type of ground pins of the multiple channel devices, and the second ground region serves as the reference ground for the second type of ground pins of the multiple channel devices. The reference ground potential of the first type of ground pins is associated with the output signal of the multiple channel devices, while the reference ground potential of the second type of ground pins is not associated with the output signal of the multiple channel devices.

[0022] In the first example embodiment, based on whether the ground pins of the channel devices are associated with the output signal, they are divided into a first type of ground pin and a second type of ground pin. Simultaneously, a first ground region and a second ground region are defined on the PCB circuit board. The first ground region serves as the reference ground for the first type of ground pins, and the second ground region serves as the reference ground for the second type of ground pins. Since the ground current in the first ground region where the first type of ground pins are located is much smaller than the ground current in the second ground region where the second type of ground pins are located, the potential difference between the first type of ground pins is smaller, thereby improving the output accuracy of each channel device.

[0023] In a specific embodiment, the first type of ground pins of the multiple channel devices includes an analog ground pin AGND; the analog ground pins AGND of the multiple channel devices are all connected to a first ground region. The second type of ground pins of the multiple channel devices include a digital ground pin DGND and a power ground pin GND; the digital ground pin DGND and the power ground pin GND of the multiple channel devices are both connected to a second ground region. In this embodiment, the first ground region can be an analog ground plane, while the digital ground pin DGND and the power ground pin GND are both connected to the second ground region, which can be a power ground plane. The first ground region and the second ground region share a common ground.

[0024] For example, both the first and second ground areas are ground planes, which can be made of ground copper material and laid on the PCB circuit board.

[0025] It should be noted that the first type of grounding pins may also include other grounding pins associated with the output signal of the channel device, and the second type of grounding pins may also include other grounding pins not associated with the output signal of the channel device; examples will not be given here. Specifically, this relates to whether it is related to the accuracy of the output signal.

[0026] In order to connect the analog ground pins of all channel devices to the reference ground of the reference source through a first ground area, the PCB board also includes a reference source, which includes an analog ground pin connected to the first ground area.

[0027] By connecting the analog ground pin of the reference source to the first ground region, the difference between the reference ground potential of the channel device and the reference ground potential of the reference source is reduced.

[0028] In the prior art, in order to reduce the difference between the reference ground potential of the channel device and the reference ground potential of the reference source, each channel device uses a reference source. However, in this example embodiment, only one reference source is needed. Therefore, compared with the prior art, the cost is reduced and the consistency of the channel device is improved.

[0029] In some embodiments, the first ground region and the second ground region are located on the same layer of the PCB circuit board, and the first ground region and the second ground region are connected by traces. The same layer can be the upper surface layer, the lower surface layer, or an intermediate layer of the PCB circuit board.

[0030] In some embodiments, the first ground region and the second ground region are located on different layers of the PCB circuit board, and the first ground region and the second ground region are connected by any one of the vias, ferrite beads or zero-ohm resistors of the PCB circuit board.

[0031] Figure 2 This is an equivalent schematic diagram of the ground plane structure of the PCB circuit board in the first example embodiment provided in this application. Figure 2 As shown, there are equivalent ground resistances Rs0, Rs1, ..., Rsn between the two reference ground potentials in the first region, and similarly, there are equivalent ground resistances R0, R1, ..., Rn between the two reference ground potentials in the second region. The ground resistances Rs0, Rs1, ..., Rsn are on the same order of magnitude as the ground resistances R0, R1, ..., Rn, while the equivalent ground current I0 is two orders of magnitude smaller than the ground current I1. Therefore, the potential difference on the ground resistances R0, R1, ..., Rn is much smaller than the potential difference on the ground resistances Rs0, Rs1, ..., Rsn (equivalent to the potential difference between the two reference ground potentials when only one region is used in the prior art). This greatly reduces the influence of the reference ground potential of each channel device on its output signal, thus improving the output accuracy of each channel device.

[0032] In the first example embodiment, both the digital ground pin DGND and the power ground pin GND are connected to the second ground area, which may cause crosstalk in the signal.

[0033] To solve this technical problem, based on the first example embodiment, such as Figure 3 As shown, the ground plane structure of the PCB circuit board proposed in the second example embodiment of this application further includes a third ground region. The third ground region is connected to the second ground region at a single point. The third ground region serves as the reference ground for the third type of ground pins of multiple channel devices. The reference ground potential of the third type of ground pins is not related to the output signals of the multiple channel devices.

[0034] The second example embodiment adds a third ground region based on the first example embodiment, and connects the second type of ground pin and the third type of ground pin separately, that is, the second type of ground pin is connected to the second ground region and the third type of ground pin is connected to the third ground region, thereby avoiding signal crosstalk between different ground pins and improving anti-interference capability.

[0035] In a specific embodiment, the second type of ground pin of the multiple channel devices includes a power ground pin (GND), which is connected to the second ground area; the third type of ground pin of the multiple channel devices includes a digital ground pin (DGND), which is connected to the third ground area. In this embodiment, the first ground area can be an analog ground plane, the second ground area can be a power ground plane, and the third ground area can be a digital ground plane. The first ground area, the second ground area, and the third ground area share a common ground.

[0036] In some embodiments, the second region and the third region are located on the same layer of the PCB circuit board and are connected by traces.

[0037] In some embodiments, the second region and the third region are located on different layers of the PCB circuit board, and the second region and the third region are connected by any one of the vias, ferrite beads or zero-ohm resistors of the PCB circuit board.

[0038] The principle behind the second example embodiment's improvement of the output accuracy of each channel device has been explained in detail in the first example embodiment and will not be repeated here.

[0039] This application also proposes a test board, including a reference source, multiple channel devices, and a PCB circuit board as described in the above embodiments.

[0040] It should be noted that the working principle and beneficial effects of the ground plane structure of the PCB circuit board have been described in detail in the above embodiments, so they will not be repeated in this embodiment.

[0041] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0042] The above embodiments merely illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A ground plane structure for a PCB circuit board, the PCB circuit board comprising multiple channel devices, characterized in that, The ground plane structure includes a first ground region and a second ground region, and the first ground region and the second ground region are connected at a single point; Wherein, the first ground area serves as the reference ground for the first type of ground pin of the plurality of channel devices, and the second ground area serves as the reference ground for the second type of ground pin of the plurality of channel devices. The reference ground potential of the first type of ground pin is associated with the output signal of the plurality of channel devices, and the reference ground potential of the second type of ground pin is not associated with the output signal of the plurality of channel devices.

2. The ground plane structure according to claim 1, characterized in that, The first type of ground pin of the plurality of channel devices includes an analog ground pin; The analog ground pins of the multiple channel devices are all connected to the first ground area.

3. The ground plane structure according to claim 2, characterized in that, The second type of ground pins of the multiple channel devices include digital ground pins and power ground pins; The digital ground pins and power ground pins of the multiple channel devices are all connected to the second ground area.

4. The ground plane structure according to claim 1, characterized in that, The PCB circuit board also includes a reference source, which includes an analog ground pin connected to the first ground area.

5. The ground plane structure according to claim 1, characterized in that, The first area and the second area are located on the same layer of the PCB circuit board, and the first area and the second area are connected by traces.

6. The ground plane structure according to claim 1, characterized in that, The first region and the second region are located on different layers of the PCB circuit board, and the first region and the second region are connected by any one of the vias, ferrite beads or zero-ohm resistors of the PCB circuit board.

7. The ground plane structure according to claim 2, characterized in that, The ground plane structure also includes a third ground region, which is connected to the second ground region at a single point. The third ground region serves as the reference ground for the third type of ground pin of the plurality of channel devices, and the reference ground potential of the third type of ground pin is not related to the output signal of the plurality of channel devices.

8. The ground plane structure according to claim 7, characterized in that, The second type of ground pin of the plurality of channel devices includes a power ground pin, which is connected to the second ground area; the third type of ground pin of the plurality of channel devices includes a digital ground pin, which is connected to the third ground area.

9. The ground plane structure according to claim 7, characterized in that, The second and third ground regions are located on the same layer of the PCB circuit board, and are connected by traces; or, The second region and the third region are located on different layers of the PCB circuit board, and the second region and the third region are connected by any one of the vias, ferrite beads or zero-ohm resistors of the PCB circuit board.

10. A test board, characterized in that, It includes a reference source, multiple channel devices, and a PCB board as described in any one of claims 1-9.

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