A low-cost servo driver high-current PCB wiring structure

Abstract

This application proposes a low-cost, high-current PCB routing structure for a servo driver, including a power board and a heat sink. The power board comprises a first layer, a second layer, a third layer, and a fourth layer stacked sequentially. Three-phase power vias, positive power vias, and negative current vias are provided on the first, second, third, and fourth layers. The first layer contains the driving circuit, the sampling circuit, and a first positive power interface copper plating area. The second layer contains a first negative power interface copper plating area and connecting lines for electronic components. The third layer contains a second positive power interface copper plating area and power interface connecting lines. The fourth layer contains a three-phase power interface copper plating area and a second negative current interface copper plating area. The heat sink is positioned at a first predetermined distance from the power board. This low-cost, high-current PCB routing structure for a servo driver solves the problem of high cost in existing high-current PCB routing for servo drivers.

Description

Technical Field

[0001] This invention relates to a low-cost, high-current PCB wiring structure for servo drivers, belonging to the field of PCB wiring technology. Background Technology

[0002] In existing technologies, PCB wiring structures are commonly used in the electrical field and are widely applied in the design of various household appliances. Specifically, they can be categorized as follows: to save space, implement multi-layer designs, or to handle high currents while considering heat dissipation, aluminum substrates, copper substrates, and ceramic substrates are generally used as the substrate. However, when these materials are used in high-current applications, their thickness limits necessitate good heat dissipation design. Using thin boards may result in the inability to handle high currents. Therefore, using aluminum substrates, copper substrates, and ceramic substrates as substrates leads to higher costs due to heat dissipation requirements and electrical isolation. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this invention is to provide a low-cost servo driver high-current PCB wiring structure, which can solve the technical problem that the cost of the existing low-cost servo driver high-current PCB wiring structure is relatively high.

[0004] According to an embodiment of the present invention, the first solution is: a low-cost servo driver high-current PCB wiring structure for PCB wiring of a low-cost servo driver high-current circuit, characterized in that the low-cost servo driver high-current circuit includes a drive circuit, a sampling circuit, a three-phase power interface, a positive DC power interface and a negative current interface;

[0005] The low-cost servo driver's high-current PCB wiring structure includes a power board and a heat sink.

[0006] The power board includes a first stack, a second stack, a third stack, and a fourth stack, which are stacked sequentially.

[0007] The first stack, the second stack, the third stack, and the fourth stack are all provided with three-phase power vias, positive power vias, and negative current vias;

[0008] The first stack layer is provided with the driving circuit, the sampling circuit and the first positive power interface copper pour area;

[0009] The second layer is provided with a first negative power interface copper pour area and electronic device connection lines;

[0010] The third layer is provided with a second positive power interface copper pour area and a power interface connection line;

[0011] The fourth layer is provided with a three-phase power interface copper pour area and a second negative power interface copper pour area.

[0012] The heat sink is positioned at a first preset distance from the power board.

[0013] Optionally, the low-cost servo driver high-current PCB wiring structure further includes a heat-conducting sheet, which is disposed between the heat sink and the power board.

[0014] Optionally, the first preset distance is 1.2 mm.

[0015] Optionally, the low-cost servo driver high-current PCB wiring structure further includes high-current terminals, which are electrically connected to the three-phase power interface, the positive DC power interface and the negative current interface respectively.

[0016] The driving circuit includes multiple MOSFETs, and the sampling circuit includes a sampling resistor;

[0017] On the first stack:

[0018] The MOS transistor and the sampling resistor are distributed in the middle of the first stack;

[0019] The first stack has opposing first and second sides, as well as opposing third and fourth sides. A mounting position for a high-current terminal is also provided on the first stack. One side of the mounting position for the high-current terminal is located near the first and third sides. A copper plating area for the first positive power interface is located between the other side of the mounting position for the high-current terminal and the second side. On the other side of the first stack, near the fourth side, a mounting position is provided for the sampling circuit and other components in the driving circuit.

[0020] Optionally, on the second stack, a full-area copper plating is performed in the area outside the three-phase power via, the positive power via, the negative current via, and the isolation area corresponding to each via to form the first negative power interface copper plating area.

[0021] Optionally, on the third stack, a full-area copper pour is performed in the area outside the three-phase power via, the positive power via, the negative current via, and the isolation area corresponding to each via to form the second positive power interface copper pour area.

[0022] Optionally, on the fourth stack, in the area outside the isolation area of ​​the positive power via and the corresponding via, the three-phase power via and the negative current via are led out in separate regions, and after dividing the remaining area, copper is poured into each via to form the copper pour area of ​​the three-phase power interface and the copper pour area of ​​the second negative power interface.

[0023] Optionally, the low-cost servo driver high-current PCB wiring structure further includes:

[0024] The power board is equipped with a power circuit and is set at a preset angle to the power board.

[0025] Optionally, the low-cost servo driver high-current PCB wiring structure further includes:

[0026] The control board is positioned parallel to the power board.

[0027] Optionally, the power board, the power supply board, and the control board are all made of standard FR4 board material.

[0028] This application employs a layered power board design. Specifically, the driving circuit, the sampling circuit, and the first positive power interface copper area are placed in the first layer; the first negative power interface copper area and the electronic component connection lines are placed in the second layer; the second positive power interface copper area and the power interface connection lines are placed in the third layer; and the three-phase power interface copper area and the second negative power interface copper area are placed in the fourth layer. This layered layout ensures a sufficiently small power loop area, thereby reducing the power board's size and optimizing the power supply loop from a three-dimensional perspective. Furthermore, the layering reduces the unit area requirements for heat dissipation and electrical isolation, thus lowering costs. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the high-current PCB wiring structure of the low-cost servo driver of the present invention.

[0030] Figure 2 This is a circuit diagram of the high-current circuit for the low-cost servo driver of the present invention.

[0031] Figure 3 This is a schematic diagram of the first stack of the power board in the high-current PCB wiring structure of the low-cost servo driver of the present invention.

[0032] Figure 4 This is a schematic diagram of the second stacked layer of the power board in the high-current PCB wiring structure of the low-cost servo driver of the present invention;

[0033] Figure 5This is a schematic diagram of the third layer of the power board in the high-current PCB wiring structure of the low-cost servo driver of the present invention.

[0034] Figure 6 This is a schematic diagram of the fourth layer of the power board in the high-current PCB wiring structure of the low-cost servo driver of the present invention.

[0035] Figure 7 This is a schematic diagram of the high-current PCB wiring structure of the low-cost servo driver of the present invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0038] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" or "several" means two or more, unless otherwise explicitly specified.

[0040] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0041] According to an embodiment of the present invention, a first solution is provided as follows: Figure 1 as well as Figure 2 As shown, a low-cost servo driver high-current PCB wiring structure is used for PCB wiring of the high-current circuit of the low-cost servo driver. The high-current circuit of the low-cost servo driver includes a drive circuit 40, a motor 50, a sampling circuit 70, a three-phase power interface, a positive DC power interface, and a negative current interface. The low-cost servo driver high-current PCB wiring structure includes a power board 10 and a heat sink.

[0042] The power board 10 includes a first stack, a second stack, a third stack, and a fourth stack arranged in sequence.

[0043] The first, second, third, and fourth stacks are each provided with three-phase power vias, positive power vias, and negative current vias; the first stack is provided with the driving circuit 40, the sampling circuit 70, and a first positive power interface copper plating area; the second stack is provided with a first negative power interface copper plating area and electronic device connection lines; the third stack is provided with a second positive power interface copper plating area and power interface connection lines; and the fourth stack is provided with a three-phase power interface copper plating area and a second negative power interface copper plating area.

[0044] The heat sink is positioned at a first preset distance from the power board 10.

[0045] This application employs a layered design for the power board 10. Specifically, the driving circuit 40, the sampling circuit 70, and the copper plating area of ​​the first positive power interface are placed in the first layer; the copper plating area of ​​the first negative power interface and the connecting lines of electronic components are placed in the second layer; the copper plating area of ​​the second positive power interface and the power interface connecting lines are placed in the third layer; and the copper plating areas of the three-phase power interface and the second negative power interface are placed in the fourth layer. This layered layout ensures a sufficiently small power loop area, thereby reducing the volume of the power board 10 and optimizing the power supply loop from a three-dimensional perspective. Furthermore, the layering reduces the unit area requirements for heat dissipation and electrical isolation, thus lowering costs.

[0046] Optionally, the low-cost servo driver high-current PCB wiring structure further includes a heat-conducting sheet, which is disposed between the heat sink and the power board 10.

[0047] By incorporating a heat-conducting sheet and selecting a material that fits snugly against the power board 10, the heat generated by the power board 10 can be transferred to the heat sink for dissipation. It should be noted that the heat-conducting sheet is a type of thermally conductive and insulating pad.

[0048] Furthermore, in the above solution, by employing a 4-layer board, both heat dissipation and loop minimization can be achieved simultaneously. By arranging the positive and negative current interfaces across 3 layers in a stacked layout, the loop area can be ensured to be sufficiently small while still covering both positive and negative current during wiring. The UVW output is located on the fourth layer, allowing direct contact with the heatsink, and vias are drilled in the power device (MOS) pads to simultaneously minimize loop size and facilitate rapid heat dissipation. In contrast, in exemplary technologies, aluminum-based and copper-based substrates typically only allow wiring to be placed on the top layer, relying on the substrate for heat transfer. In this case, placing the wiring on the top layer, occupying only one layer, fails to achieve optimal loop performance.

[0049] Optionally, the first preset distance is 1.2 mm.

[0050] The heat-conducting sheet needs to quickly transfer heat to the heat sink. To increase the heat dissipation effect, the distance between the PCB and the heat sink base plate should be as small as possible, and the thermal conductivity should be as high as possible. When the first preset distance is 1.2mm, a good electrical isolation effect can also be achieved. In the event of processing errors or possible damage to the heat-conducting sheet, electrical isolation can also be achieved by the thickness of the heat-conducting sheet itself, ensuring safe use and preventing the power board 10 from directly contacting the outside through the heat sink and causing electrical hazards.

[0051] Optionally, refer to Figure 3 As shown, the low-cost servo driver high-current PCB wiring structure also includes a high-current terminal 101, which is electrically connected to the three-phase power interface, the positive DC power interface and the negative current interface respectively; the drive circuit 40 includes multiple MOSFETs and the sampling circuit 70 includes a sampling resistor.

[0052] On the first stack:

[0053] The MOS transistor and the sampling resistor are distributed in the middle of the first stack;

[0054] The first stack has opposing first and second sides, as well as opposing third and fourth sides. A mounting position for a high-current terminal 101 is also provided on the first stack. One side of the mounting position for the high-current terminal 101 is located close to the first and third sides. A first positive power interface copper pour area 10111 is provided between the other side of the mounting position for the high-current terminal 101 and the second side. On the other side of the first stack, near the fourth side, a mounting position for the sampling circuit 70 and other devices in the driving circuit 40 is provided.

[0055] Among them, the high-current terminal 101 is a grid-shaped terminal. Current processes for copper-based, aluminum-based, and ceramic-based substrates cannot directly mount this terminal on the PCB board. However, this application can directly mount it on standard FR4 board material, saving installation costs. In addition, a first positive power interface copper pour area 10111 is provided between the other side of the mounting position of the high-current terminal 101 and the second side. The width of the power trace can be increased to ensure the passage of high current.

[0056] Optionally, refer to Figure 4 As shown, on the second stack, in the area outside the three-phase power via, the positive power via, and the negative current via, and the isolation area corresponding to each via, full-area copper pouring is performed to form the first negative power interface copper pouring area 10121.

[0057] At this time, the first negative power interface copper pour area 10121 is connected to the negative current interface through the negative current via 1012, and then connected to the negative current pin in the high current terminal 101. By pouring copper over the entire area, the negative current can flow through the entire area, thereby avoiding abnormal heat generation caused by an excessively narrow or small flow area in high current applications, achieving uniform and lower heat generation, and thus achieving rapid heat dissipation through a large area, which enhances heat dissipation. In addition, since the first positive power interface copper pour area 10111 is provided on the first stack, the first negative power interface copper pour area 10121 can be coupled with the first positive power interface copper pour area 10111, thereby reducing the parasitic inductance of the two copper pour areas and reducing the external conduction and radiation of the induced electric field of the two copper pour areas.

[0058] In practical applications, it can achieve better heat dissipation, reduce the external conduction and radiation of induced electric fields with a smaller size and thinner design, and reduce the overall impact of high current circuits on the surrounding electrical environment.

[0059] Optionally, refer to Figure 5As shown, on the third stack, in the area outside the three-phase power vias uvw, the positive power via 1011, and the negative current via 1012, and the isolation area corresponding to each via, full-area copper pouring is performed to form the second positive power interface copper pouring area 10112.

[0060] At this time, the second positive power interface copper plating area 10112 is connected to the positive current interface through the positive current via 1011, thereby connecting to the positive current pin in the high current terminal 101. By plating the entire area with copper, the positive current can flow through the entire area, thus avoiding abnormal heating caused by an excessively narrow or small flow area in high-current applications. This achieves uniform and lower heat generation, enabling rapid heat dissipation through a large area, enhancing heat dissipation, and reducing the positive current flow loop, thereby reducing the loop parasitic inductance. Furthermore, since the second stack has the first negative power interface copper plating area 10121, the second positive power interface copper plating area 10112 can couple with the first negative power interface copper plating area 10121, thereby reducing the parasitic inductance of the two copper plating areas and reducing the external conduction and radiation of the induced electric field from the two copper plating areas.

[0061] In practical applications, it can achieve better heat dissipation, reduce the external conduction and radiation of induced electric fields with a smaller size and thinner design, and reduce the overall impact of high current circuits on the surrounding electrical environment.

[0062] Optionally, refer to Figure 6 As shown, on the fourth stack, in the area outside the isolation area of ​​the positive power via 1011 and the corresponding via, the three-phase power via and the negative current via are led out in separate regions. After dividing the remaining area, copper is poured into each via to form the copper pour area of ​​the three-phase power interface and the copper pour area of ​​the second negative power interface.

[0063] At this time, the second negative power interface copper pour area is connected to the negative current interface through the negative current via 1012, and then connected to the negative current pin in the high current terminal 101. By increasing the copper pour area, the negative current can flow through a larger area, thereby avoiding abnormal heat generation caused by an excessively narrow or small flow area in high current applications, achieving uniform and lower heat generation, and thus achieving rapid heat dissipation through a large area, which enhances heat dissipation. In addition, since the second positive power interface copper pour area 10112 is provided on the third stack, the second negative power interface copper pour area can be coupled with the second positive power interface copper pour area 10112, thereby reducing the parasitic inductance of the two copper pour areas and reducing the external conduction and radiation of the induced electric field of the two copper pour areas.

[0064] In practical applications, it can achieve better heat dissipation, reduce the external conduction and radiation of induced electric fields with a smaller size and thinner design, and reduce the overall impact of high current circuits on the surrounding electrical environment.

[0065] Optionally, the positive power via 1011, the negative current via 1012, the first positive power interface copper area, the second positive power interface copper area 10112, the first negative power interface copper area, and the second negative power interface copper area all carry DC power.

[0066] In addition, by placing the UVW wiring directly on the bottom layer, it can directly contact the heat sink, thereby increasing heat dissipation. Furthermore, for all MOS heat-generating devices at their mounting positions on the power board 10, the bottom heat sink is also designed to directly contact the heat sink, thereby accelerating heat dissipation.

[0067] Optionally, refer to Figure 7 As shown, the low-cost servo driver high-current PCB wiring structure also includes:

[0068] The power board is equipped with a power circuit 60 and is set at a preset angle to the power board 10.

[0069] The power board is set at a preset angle to the power board 10, which can avoid mutual interference between the induced electric and magnetic fields, improve power density, and keep the power line away from other control signals.

[0070] Since the power supply and UVW output sections are both high-frequency, high-interference signals, they are subject to electric and magnetic field interference. When the preset angle is 90 degrees, the interference reduction effect is optimal because they are perpendicularly intersecting.

[0071] Optionally, refer to Figure 7 As shown, the low-cost servo driver high-current PCB wiring structure also includes:

[0072] The control board is positioned parallel to the power board.

[0073] The control board is positioned parallel to the power board. Since the control board only carries the control circuitry and is relatively small, the components on the power board can be arranged reasonably. For example, shorter components can be grouped together, and taller components can be placed outside the projection of the control board onto the power board. This minimizes the extra space required for the control board and further reduces the final product size.

[0074] Optionally, the power board, the power supply board, and the control board are all made of standard FR4 board material.

[0075] In the exemplary technology, considering the large current, it is necessary to design PCB riveting studs or surface-mount conductive brackets to carry the large current. However, this will place high demands on the installation process, result in a large amount of installation work, and thus cause relatively large labor costs.

[0076] In this application, by using standard FR4 board material and combining it with the aforementioned multi-layer layout design, it is possible to balance minimizing loop size and heat dissipation while also reducing board thickness and industrialization difficulty. It eliminates the need for cumbersome PCB riveting studs or surface-mount conductive bracket designs, relying solely on methods such as... Figure 7 The high-current terminal 101 shown can be directly installed to achieve high-current conversion, which reduces the installation difficulty and saves labor costs.

[0077] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.

[0078] Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low-cost servo driver high-current PCB routing structure, used for PCB routing of high-current circuits in a low-cost servo driver, characterized in that, The low-cost servo driver high-current circuit includes a drive circuit, a sampling circuit, a three-phase power interface, a positive DC power interface, and a negative current interface. The low-cost servo driver's high-current PCB wiring structure includes a power board and a heat sink. The power board includes a first stack, a second stack, a third stack, and a fourth stack, which are stacked sequentially. The first stack, the second stack, the third stack, and the fourth stack are all provided with three-phase power vias, positive power vias, and negative current vias; The first stack layer is provided with the driving circuit, the sampling circuit and the first positive power interface copper pour area; The second layer is provided with a first negative power interface copper pour area and electronic device connection lines; The third layer is provided with a second positive power interface copper pour area and a power interface connection line; The fourth layer is provided with a three-phase power interface copper pour area and a second negative power interface copper pour area. The heat sink is positioned at a first preset distance from the power board; The low-cost servo driver high-current PCB wiring structure also includes a heat-conducting sheet, which is disposed between the heat sink and the power board; On the third stack, in the area outside the three-phase power via, the positive power via, the negative current via, and the isolation area corresponding to each via, full-area copper pouring is performed to form the second positive power interface copper pouring area.

2. The low-cost servo driver high-current PCB wiring structure according to claim 1, characterized in that, The first preset distance is 1.2mm.

3. The low-cost servo driver high-current PCB wiring structure according to claim 1, characterized in that, The low-cost servo driver's high-current PCB wiring structure also includes high-current terminals, which are electrically connected to the three-phase power interface, the positive DC power interface, and the negative current interface, respectively; the driving circuit includes multiple MOSFETs, and the sampling circuit includes sampling resistors; On the first stack: The MOS transistor and the sampling resistor are distributed in the middle of the first stack; The first stack has opposing first and second sides, as well as opposing third and fourth sides. The first stack also has mounting positions for high-current terminals. One side of the mounting position for the high-current terminal is located close to the first and third sides. The other side of the mounting position for the high-current terminal is located between the high-current terminal and the second side, and a copper pour area for the first positive power interface is located between the second and third sides. On the other side of the first stack, near the fourth side, is a mounting position for the sampling circuit and other devices in the driving circuit.

4. The low-cost servo driver high-current PCB wiring structure according to claim 1, characterized in that, On the second stack, copper plating is performed in the area outside the three-phase power via, the positive power via, the negative current via, and the isolation area corresponding to each via to form the first negative power interface copper plating area.

5. The low-cost servo driver high-current PCB wiring structure according to claim 1, characterized in that, On the fourth stack, in the area outside the isolation area of ​​the positive power via and the corresponding via, the three-phase power via and the negative current via are led out in separate regions. After dividing the remaining area, copper is poured into each via to form the copper pour area of ​​the three-phase power interface and the copper pour area of ​​the second negative power interface.

6. The low-cost servo driver high-current PCB wiring structure according to claim 1, characterized in that, The low-cost servo driver's high-current PCB wiring structure also includes: The power board is equipped with a power circuit and is set at a preset angle to the power board.

7. The low-cost servo driver high-current PCB wiring structure according to claim 6, characterized in that, The low-cost servo driver's high-current PCB wiring structure also includes: The control board is positioned parallel to the power board.

8. The low-cost servo driver high-current PCB wiring structure according to claim 7, characterized in that, The power board, the power supply board, and the control board are all made of standard FR4 board material.

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