A multi-signal switching adapter plate and a design method thereof

Abstract

The application discloses a multi-signal switching adapter plate and a design method thereof, and belongs to the technical field of adapter printed boards, and comprises a printed board, a welding resistor, after a CRM connector appears on the printed board, when bifurcation occurs, the welding resistor is arranged in the form of punching on the upper layer and the lower layer of the printed board, namely, the welding resistor is used as the welding resistor, signal cables, the signal cables comprise LVDS signal cables and CAN signal cables, and the LVDS signal is transmitted in the wiring mode of the punched welding resistor, and the CAN signal is transmitted in the wiring mode of the non-punched welding resistor. The application realizes the compatibility of the same tool to two kinds of modules, the reliability of the application meets the actual use, 50% of tooling is saved, and certain economic benefits are obtained.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board (PCB) technology, and more specifically, to a multi-signal switching PCB and its design method. Background Technology

[0002] The flexible digital testing and commissioning production line uses robotic arms to clamp products under test, which raises the requirement for uniformity in the shape and interface of the product test fixtures. Channel-type products A and B have the same hardware interface and require the same instruments for testing, but their internal communication protocols differ. Product A uses a synchronous LVDS bus, while product B uses both a CAN bus and an asynchronous LVDS bus, leading to differences in the test fixtures (…). Figure 1 The low-frequency connections of the module adapters differ. Using different tooling for testing would be too costly. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a multi-signal switching adapter board and its design method, which realizes the compatibility of two modules with the same tooling. After actual use testing, its reliability meets the actual use requirements, saves 50% of the tooling, and has certain economic benefits.

[0004] The objective of this invention is achieved through the following solution:

[0005] A multi-signal switching adapter board, comprising:

[0006] Printed circuit board;

[0007] Selective soldering resistors are used when the CRM connector appears on the printed circuit board and branches out. They are arranged in the upper and lower layers of the printed circuit board by drilling holes.

[0008] The signal cables include LVDS signal cables and CAN signal cables; LVDS signals are transmitted using a routing method that involves punching holes and then soldering resistors, while CAN signals are transmitted using a routing method that involves not punching holes and then soldering resistors.

[0009] Furthermore, the LVDS signal is a signal with a common mode voltage of 1.2V and a differential mode voltage of 300-600mV, with a maximum speed of 10MHz.

[0010] Furthermore, the CAN signal has a voltage range of 1.5V to 3.5V and a maximum speed of 1MHz.

[0011] Furthermore, the welding resistor includes a 0603 resistor.

[0012] Furthermore, the welding resistor includes a 0402 resistor.

[0013] Furthermore, placing the hole location under the pad can further reduce signal interference.

[0014] Furthermore, during the forking process, the forks on the printed circuit board are used for LVDS signal routing.

[0015] A multi-signal switching adapter board design method addresses the issue of tooling incompatibility by selectively soldering resistors on the printed circuit board for channel switching; by selectively soldering resistors on the adapter printed circuit board, compatibility of the same tooling with two modules is achieved.

[0016] Furthermore, the tooling is a module adapter.

[0017] Furthermore, the step of selectively soldering resistors on the adapter printed circuit board includes the following sub-steps:

[0018] After the CRM connector appeared on the printed circuit board, when it branched out, it adopted the form of punching holes to place soldering resistors on the upper and lower layers of the printed circuit board, which served as the selected soldering resistors; and, the LVDS signal was transmitted using the routing method of soldering resistors after punching holes, while the CAN signal was transmitted using the routing method of soldering resistors without punching holes.

[0019] The beneficial effects of this invention include:

[0020] (1) This invention proposes a universal adapter board and its design method, which can achieve compatibility between two products and meet the needs of flexible production lines.

[0021] (2) This invention addresses the problem of incompatibility between tooling (module adapters) by proposing a solution of selectively soldering resistors on the printed circuit board for channel switching. By selectively soldering resistors on the adapter printed circuit board, compatibility between the same tooling and two modules is achieved. Actual use testing has shown that its reliability meets practical application requirements. This saves 50% of the tooling, resulting in certain economic benefits. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 Test interconnect diagrams for products;

[0024] Figure 2 Schematic diagram of the selected welding scheme;

[0025] Figure 3 This is a schematic diagram showing the soldering method and wiring.

[0026] Figure 4 This is a schematic diagram illustrating the factors affecting signal quality.

[0027] Figure 5 A schematic diagram illustrating methods to further reduce the impact of LVDS signals. Detailed Implementation

[0028] All features disclosed in all embodiments of this specification, or steps in all methods or processes implied in the disclosure, may be combined and / or extended or replaced in any way, except for mutually exclusive features and / or steps.

[0029] like Figures 1-5 As shown, this invention proposes a universal adapter board and its design method, which can achieve compatibility with two products and meet the needs of flexible production lines.

[0030] Design concept: Controlling channel switching is key to achieving general functionality. The following points were considered during the design process:

[0031] There is signal incompatibility between pins 39, 40, 59, and 60 of products A and B, and path switching is required to achieve a universal effect.

[0032] The tooling needs to undergo vibration and temperature tests, which places high demands on its durability. Using a switch to change the switch would cause reliability issues.

[0033] Both CAN and LVDS are differential signals, which have high impedance requirements. Forked lines on the PCB or on the cable will cause significant signal reflection.

[0034] Printed circuit board soldering resistor design, such as Figure 2 The schematic diagram shown has been simplified. Figure 2 Each cable in the circuit represents a differential signal. Firstly, because differential signals have high impedance requirements, selective soldering resistors can introduce local impedance discontinuities. Secondly, both branching lines on the PCB and branching lines within the cable itself can cause significant signal reflections. From a signal integrity perspective, this can be addressed in the following ways: With the advent of CRM connectors on the printed circuit board, when branching, vias are used to place selective soldering resistors on the upper and lower layers of the printed circuit board. Depending on the signal rate and requirements, different methods can be adopted... Figure 3 The soldering method is shown below. The LVDS signal uses a common-mode voltage of 1.2V and a differential-mode voltage of 300-600mV, with a maximum speed of approximately 10MHz. The CAN signal uses a voltage range of 1.5V-3.5V, with a maximum speed of approximately 1MHz. The LVDS signal is transmitted using a trace method with vias and soldered resistors, while the CAN signal is transmitted using a trace method with without vias and soldered resistors.

[0035] Soldering the circuit can cause impedance discontinuities, but choosing small resistors like 0603 or 0402 will not cause significant impedance discontinuities. Additionally, the branching section can negatively impact reflections, such as... Figure 3 As shown, the shorter branch at the top is suitable for LVDS signal routing. In practice, resistor selection doesn't require frequent adjustments, so placing the via under the pad further reduces signal interference, with virtually no impact on LVDS signals.

[0036] This invention addresses the incompatibility issue of tooling (module adapters) by proposing a solution of selectively soldering resistors on the printed circuit board (PCB) for channel switching. By soldering resistors onto the adapter PCB, compatibility between the same tooling and two different modules is achieved. Actual usage testing has demonstrated its reliability meets practical application requirements. This saves 50% of tooling, resulting in significant economic benefits.

[0037] It should be noted that, within the scope of protection defined in the claims of this invention, the following embodiments can be combined and / or extended or replaced in any logical manner from the above specific embodiments, such as the disclosed technical principles, disclosed technical features or implicitly disclosed technical features.

[0038] Example 1

[0039] A multi-signal switching adapter board, comprising:

[0040] Printed circuit board;

[0041] Selective soldering resistors are used when the CRM connector appears on the printed circuit board and branches out. They are arranged in the upper and lower layers of the printed circuit board by drilling holes.

[0042] The signal cables include LVDS signal cables and CAN signal cables; LVDS signals are transmitted using a routing method that involves punching holes and then soldering resistors, while CAN signals are transmitted using a routing method that involves not punching holes and then soldering resistors.

[0043] In this embodiment, the LVDS signal is a signal with a common mode voltage of 1.2V and a differential mode voltage of 300-600mV, with a maximum speed of 10MHz.

[0044] In this embodiment, the CAN signal has a voltage range of 1.5V to 3.5V and a maximum speed of 1MHz.

[0045] In this embodiment, the welding resistor includes a 0603 resistor.

[0046] In this embodiment, the welding resistor includes a 0402 resistor.

[0047] In this embodiment, placing the hole under the pad further reduces signal interference.

[0048] In this embodiment, during the forking process, the forks on the printed circuit board are used for LVDS signal routing.

[0049] Example 2

[0050] A multi-signal switching adapter board design method addresses the issue of tooling incompatibility by selectively soldering resistors on the printed circuit board for channel switching; by selectively soldering resistors on the adapter printed circuit board, compatibility of the same tooling with two modules is achieved.

[0051] In this embodiment, the tooling is a module adapter.

[0052] Example 3

[0053] Based on Example 2, the step of selecting and soldering resistors on the adapter printed circuit board includes the following sub-steps:

[0054] After the CRM connector appeared on the printed circuit board, when it branched out, it adopted the form of punching holes to place soldering resistors on the upper and lower layers of the printed circuit board, which served as the selected soldering resistors; and, the LVDS signal was transmitted using the routing method of soldering resistors after punching holes, while the CAN signal was transmitted using the routing method of soldering resistors without punching holes.

[0055] The units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0056] According to one aspect of the present invention, a computer program product or computer program is provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described above.

[0057] In another aspect, embodiments of the present invention also provide a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.

[0058] All parts not covered in this invention are the same as or can be implemented using existing technologies.

[0059] The above technical solution is only one embodiment of the present invention. For those skilled in the art, based on the application methods and principles disclosed in the present invention, it is easy to make various types of improvements or modifications, and not limited to the methods described in the above specific embodiments of the present invention. Therefore, the methods described above are only preferred and have no limiting significance.

[0060] In addition to the examples above, those skilled in the art can obtain other embodiments by making modifications based on the above disclosure or by utilizing knowledge or technology in related fields. Features of the various embodiments can be interchanged or substituted. Modifications and changes made by those skilled in the art do not depart from the spirit and scope of the present invention.

[0061] All of these should fall within the scope of protection of the appended claims of this invention.

Claims

1. A multi-signal switching adapter board, characterized in that, include: Printed circuit board; Selective soldering resistors are used when the CRM connector appears on the printed circuit board and branches out. They are arranged in the upper and lower layers of the printed circuit board by drilling holes. The signal cables include LVDS signal cables and CAN signal cables; LVDS signals are transmitted using a routing method that involves punching holes and then soldering resistors, while CAN signals are transmitted using a routing method that involves soldering resistors without punching holes; the LVDS signals are signals with a common mode voltage of 1.2V and a differential mode voltage of 300~600mV, with a maximum speed of 10MHz; The CAN signal has a voltage range of 1.5V to 3.5V and a maximum speed of 1MHz; During forking, the forks on the printed circuit board are used for LVDS signal routing.

2. The multi-signal switching adapter board according to claim 1, characterized in that, The welding resistance includes 0603 resistors.

3. The multi-signal switching adapter board according to claim 1, characterized in that, The welding resistance includes 0402 resistors.

4. The multi-signal switching adapter board according to claim 1, characterized in that, Placing the hole under the pad can further reduce signal interference.

5. A design method for a multi-signal switching adapter board, characterized in that, Using the multi-signal switching adapter board according to any one of claims 1 to 4, to address the problem of tooling incompatibility, resistors are selectively soldered on the printed circuit board to perform channel switching; by selectively soldering resistors on the adapter printed circuit board, compatibility of the same tooling with two modules is achieved.

6. The multi-signal switching adapter board design method according to claim 5, characterized in that, The tooling is a module adapter.

7. The multi-signal switching adapter board design method according to claim 5, characterized in that, The process of selecting and soldering resistors on the adapter printed circuit board includes the following sub-steps: After the CRM connector appeared on the printed circuit board, when it branched out, it adopted the form of punching holes to place soldering resistors on the upper and lower layers of the printed circuit board, which served as the selected soldering resistors; and, the LVDS signal was transmitted using the routing method of soldering resistors after punching holes, while the CAN signal was transmitted using the routing method of soldering resistors without punching holes.

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