PCB layout structure of driver

Abstract

Disclosed in the present invention is a PCB layout structure of a driver, comprising: a circuit board and, arranged on the circuit board, an input terminal interface, a power supply module, an inversion module, an isolation chip, a plurality of driving modules and a docking control board signal terminal. The PCB layout structure of a driver in the present invention has reasonable wiring, can solve interference of high-frequency signals with the switching of MOS switch transistors so as to avoid simultaneously turning on an upper and a lower transistor and to improve safety, can well isolate strong and weak electricity so as to solve the problems of large carrying current and heat dissipation, and has a simple structure.

Description

Driver PCB layout structure

[0001] This invention claims priority to Chinese patent application number 202311593155.6, filed with the Patent Office of China on November 27, 2023, and entitled “PCB layout structure of driver”. The entire contents of this application are incorporated herein by reference. Technical Field

[0002] The present invention relates to the field of PCB layout, and in particular to a PCB layout structure of a driver. Background Art

[0003] A servo motor driver is a controller used to drive and control a servo motor and is part of a servo system. It receives command signals from the control system and transmits current to the servo motor, producing motion proportional to the command signal. Servo motor drivers typically control parameters such as position, speed, and torque of the servo motor, achieving high-precision positioning of the transmission system.

[0004] Unlike traditional drives, high-performance drives enable high-speed, high-precision, and highly detailed motion control, with switching frequencies reaching 100 kHz. This places higher demands on the design of switching transistors and PCBs. Existing servo motor drive PCB layouts are susceptible to high-frequency signals and have poor anti-interference capabilities.

[0005] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0006] Summary of the Invention

[0007] The purpose of the present invention is to provide a PCB layout structure of a driver, which can reduce the influence of high-frequency signals and prevent the switch tube from being misinterferenced and turned on, resulting in tube explosion and other EMS signal interference.

[0008] To achieve the above-mentioned objectives, an embodiment of the present invention provides a PCB layout structure of a driver, characterized by comprising: a circuit board and an input terminal interface, a power module, an inverter module, an isolation chip, a plurality of driver modules, and a docking control board signal terminal arranged on the circuit board;

[0009] The circuit board is divided into an input filter protection area, a power supply area, a detection area, and a drive area. The input terminal interface is provided at one edge of the circuit board. The detection area is located on one side of the input terminal interface. The signal terminal of the docking control board is located on the other side of the detection area. The drive area is located on the other side of the signal terminal of the docking control board. The power supply area is located on one side of the input terminal interface and close to the detection area. The input filter protection area is located on one side of the input terminal interface and close to the power supply area and the drive area.

[0010] The inverter module is composed of multiple MOS switch tubes. The isolation chip, multiple MOS switch tubes and multiple drive modules are located in the drive area. The signal terminal of the docking control board is connected to the drive module through the isolation chip. The power module is located in the power area and is connected to the input terminal interface, isolation chip and drive module.

[0011] In one or more embodiments of the present invention, the body diode of the MOS switch tube is located on the back side of the circuit board.

[0012] In one or more embodiments of the present invention, isolation zones are provided between the driving modules.

[0013] In one or more embodiments of the present invention, the driver also includes an impact isolation module, a bus detection module, a regeneration circuit module, a fan brake module and a current sampling module arranged on the circuit board, and the impact isolation module, bus detection module, regeneration circuit module and fan brake module are located in the detection area, and the impact isolation module, bus detection module, regeneration circuit module and fan brake module are all connected to the signal terminal of the docking control board through the corresponding isolation module, and there is an isolation belt between the power supply module, impact isolation module, bus detection module, regeneration circuit module, fan brake module and current sampling module.

[0014] In one or more embodiments of the present invention, there are isolation belts between the connecting lines between the current sampling module and the input terminal interface, the connecting lines between the fan brake module and the input terminal interface, the connecting lines between the bus detection module and the input terminal interface, and the connecting lines between the power module and the input terminal interface.

[0015] In one or more embodiments of the present invention, the driver further includes a phase loss detection module, a three-phase input protection module, a bus filter module, an anti-power-on shock module and a rectifier module arranged on a circuit board, and the phase loss detection module, the three-phase input protection module, the bus filter module, the anti-power-on shock module and the rectifier module are located in the input filter protection area.

[0016] In one or more embodiments of the present invention, the three-phase input protection module is close to the power module and has an isolation zone between the three-phase input protection module and the power module.

[0017] In one or more embodiments of the present invention, the distance between the MOS switch tubes is not less than 2 mm.

[0018] In one or more embodiments of the present invention, the driver includes an impact isolation module and an anti-power-on impact module arranged on a circuit board, the impact isolation module is located in a detection area, and the anti-power-on impact module is located in an input filter protection area. The connecting lines of the impact isolation module and the anti-power-on impact module pass through the power module and have an isolation zone between them.

[0019] In one or more embodiments of the present invention, the driver further includes a current sampling module disposed on a circuit board, and an isolation zone is provided between a connection line between the current sampling module and the MOS switch tube and the driving circuit.

[0020] Compared with the prior art, the PCB layout structure of the driver according to the embodiment of the present invention has reasonable wiring, can solve the interference caused by high-frequency signals on the switching of the MOS switch tube, prevent the upper and lower tubes from being turned on at the same time, improve safety, can well isolate strong and weak electricity, solve the problems of large current carrying and heat dissipation, and has a simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a circuit layout diagram of a PCB layout structure of a driver according to an embodiment of the present invention.

[0022] FIG. 2 is a partial circuit diagram of a driver according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0024] Unless expressly stated otherwise, throughout the specification and claims, the term "comprise" or variations such as "include" or "comprising", etc., will be understood to include the stated elements or components but not to exclude other elements or other components.

[0025] The terms "coupled," "connected," or "connected" as used in this specification encompass both direct and indirect connections. An indirect connection is a connection made through an intermediate medium, such as an electrically conductive medium, which may have parasitic inductance or capacitance. An indirect connection may also include a connection through other active or passive devices, such as switches, follower circuits, or other circuits or components, to achieve the same or similar functional objectives. Furthermore, in the present invention, terms such as "first" and "second" are primarily used to distinguish one technical feature from another and do not necessarily require or imply a specific relationship, quantity, or order between these technical features.

[0026] As shown in Figure 1, a PCB layout structure of a driver includes: a circuit board 100 and an input terminal interface, a power module, a shock isolation module, a bus detection module, a regeneration circuit module, a fan brake module, a current sampling module, a phase loss detection module, a three-phase input protection module, a bus filter module, an anti-power-on shock module, a rectifier module, an inverter module, an isolation chip, multiple drive modules, and a docking control board signal terminal.

[0027] In one embodiment, the input terminal interface includes L1, L2, L3, L1C, L2C, B1 / +, B2, B3, N, U, V, and W. L1, L2, and L3 are connected to three-phase AC power, L1C and L2C are connected to 220V single-phase AC power, and U, V, and W are connected to motor M. If a built-in regenerative resistor is used, a shorting link must be connected between B2 and B3. If an external regenerative resistor is used, the shorting link between B2 and B3 must be removed, and an external regenerative resistor must be connected between B1 / + and B2. (B1 / + and N correspond to bus PN and can be used for debugging. That is, when a problem with the drive is detected, the voltage between bus PN can be used to determine if there is an abnormality.)

[0028] The three-phase input protection module is connected to ports L1, L2, and L3. It includes X capacitors, Y capacitors, varistors, and fuse circuits. Three Y capacitors are provided and are connected to ports L1, L2, L3, and ground, respectively. Three X capacitors are also provided and are connected between any two ports among ports L1, L2, and L3. Three varistors are also provided and are connected in parallel with the X capacitors. The purpose of the three-phase input protection module is to protect subsequent circuits from other influences such as surges and noise.

[0029] The rectifier module is connected to the L1 port, L2 port, and L3 port. The rectifier module includes a rectifier bridge circuit. The purpose of the rectifier module is to rectify AC power into DC power and transmit it to the bus filter module through the bus PN. P is the bus and N is the ground.

[0030] The bus filter module is composed of multiple electrolytic capacitors, which filter the voltage ripple between the bus PN. Because the DC voltage waveform after rectification by the rectifier module is very unstable, most of the AC components can be filtered out by parallel capacitors, making the DC voltage more stable and preventing the DC voltage from affecting the operation of the motor M.

[0031] The power-on surge protection circuit module consists of a resistor and a relay (switch). Since the electrolytic capacitor is directly connected in parallel to the busbar PN, it will be subjected to a surge at the moment of power-on, requiring a resistor to limit the current. However, if the resistor is turned on for a long time, it will cause severe heat loss. Therefore, a relay (switch) must be used to short-circuit the resistor after the power is stabilized.

[0032] As shown in Figure 2, the inverter module includes six MOS switches (T1, T2, T3, T4, T5, and T6) and six diodes (D1, D2, D3, D4, D5, and D6). The cathodes and anodes of the diodes (D1, D2, D3, D4, D5, and D6) are connected to the drains and sources of the corresponding MOS switches (T1, T2, T3, T4, T5, and T6). The inverter module converts direct current (DC) into alternating current (AC). The six MOS switches are mounted on heat sink fins, and a fan is placed on one side of the fins to cool the device.

[0033] The driver module includes a driver chip that controls the on and off switching of MOS switches. Six driver modules are used to control the six MOS switches T1, T2, T3, T4, T5, and T6. The combination of these MOS switches T1, T2, T3, T4, T5, and T6 rotates the motor M.

[0034] As shown in FIG1 , both the isolation module and the isolation chip include an optocoupler circuit for isolating the driving signal and protecting the isolation front-end circuit.

[0035] As shown in Figure 1, the signal terminals of the docking control board are connected to the impact isolation module, bus detection module, regeneration circuit module and fan brake module to receive the signals output by each module. The signal terminals of the docking control board are also connected to the control board to control the processing and transmission of signals.

[0036] As shown in Figure 1 and Figure 2, the current sampling module includes three current sensors, which are respectively connected in series in the connection lines between the UVW phases of the motor M and the six MOS tubes, and are used to collect the currents of the UVW phases of the motor M, and transmit the collected signals to the control board through the signal terminals of the docking control board for analysis, so as to monitor the condition of the motor M and control the motor M.

[0037] As shown in Figure 1, the bus detection module is connected to the B1 / + port and the N port through the bus PN. The bus detection module includes a resistor and an isolated ADC. The resistor is connected in series to the bus PN for voltage division. The ADC is used to convert the voltage on the resistor. The output signal of the bus detection module is uploaded to the control board through the signal terminal of the docking control board to process the output signal and determine whether the voltage between the bus PN is overvoltage or undervoltage.

[0038] The regeneration circuit module consists of a MOS transistor and a regeneration resistor connected in series on the busbar (PN). If the busbar voltage is 390V (which can be defined differently as needed), the MOS transistor is controlled to turn on, thereby connecting the regeneration resistor to the circuit to reduce the voltage. If the three-phase AC power is disconnected, the MOS transistor is controlled to activate the regeneration resistor, which quickly discharges the energy stored in the electrolytic capacitor through the regeneration resistor to ensure personal safety.

[0039] The phase loss detection module is connected to the L1 port, L2 port, and L3 port. It drives the isolation optocoupler to output a signal through the built-in diode voltage divider. The output signal of the phase loss detection module is uploaded to the control board through the signal terminal of the docking control board for processing and judgment. It is used to detect whether the L1 port, L2 port, and L3 port are broken.

[0040] The power module is connected to the L1C port and the L2C port. The power module is used to output multiple DC power channels (such as 5V, 12V, 20V, etc.) through the built-in flyback switching circuit to power the driver module, isolation chip and other circuits.

[0041] The fan brake module receives the fan drive signal through the signal terminal of the docking control board, and drives the fan through the optocoupler isolation drive circuit to achieve the purpose of heat dissipation. It can generate a feedback signal based on the detected temperature data to achieve speed regulation.

[0042] It's important to note that since the voltage between three-phase AC power and the busbar PN is approximately 311V, these voltages are considered high voltage and must be isolated from low-voltage (such as 5V) power supplies or low-voltage signals. The bold lines in Figure 1 represent isolation zones to maintain safe distances, but this is not limited to the areas shown. The surge isolation module, busbar detection module, regeneration circuit module, and fan brake module all utilize isolation modules (such as optocouplers) to isolate them from the signal terminals on the docking control board.

[0043] The driver also includes other auxiliary modules such as temperature detection and indicator lights.

[0044] As shown in Figure 1, the circuit board 100 is divided into an input filter protection zone 110, a power supply zone 120, a detection zone 130, and a drive zone 140. The input terminal interface is located at one edge of the circuit board 100. The detection zone 130 is located on one side of the input terminal interface. The signal terminals for the docking control board are located on the other side of the detection zone 130. The drive zone 140 is located on the other side of the signal terminals for the docking control board. The power supply zone 120 is located on one side of the input terminal interface and is close to the power supply zone 120. The input filter protection zone 110 is located on one side of the input terminal interface and is close to the power supply zone 120 and the drive zone 140.

[0045] Specifically, in Figure 1 , the input terminal interface is located at the left edge of the circuit board 100, the detection area 130 is located to the right of the input terminal interface, the docking control board signal terminal is located to the right of the detection area 130, and the drive area 140 is located to the right of the docking control board signal terminal. The power supply area 120 is located to the right of the input terminal interface and above the detection area 130. The input filter protection area 110 is located to the right of the input terminal interface and above the power supply area 120 and the drive area 140. As can be seen from Figure 1 , the input filter protection area 110, the power supply area 120, and the detection area 130 are arranged side by side from top to bottom. The power supply area 120, the detection area 130, and the drive area 140 are located on both sides below the input filter protection area 110.

[0046] In conjunction with Figures 1 and 2, the inverter module is composed of multiple MOS switch tubes. The isolation chip, multiple MOS switch tubes, and multiple driver modules are located in the driver area 140, and the signal terminals of the docking control board are connected to the driver modules through the isolation chip. In one embodiment, six MOS switch tubes T1, T4, T3, T6, T5, and T2 and six driver modules are provided. The six MOS switch tubes T1, T4, T3, T6, T5, and T2 are arranged side by side from top to bottom, and the six driver modules are arranged side by side from top to bottom and correspond one to one with the MOS switch tubes. The isolation chip, driver module, and MOS switch tube are arranged in sequence. The body diode of the MOS switch tube is located on the back of the circuit board 100. An isolation strip 11 is provided between two adjacent driver modules. The distance between two adjacent MOS switch tubes is not less than 2 mm.

[0047] The power module is located in the power area 120 .

[0048] The surge isolation module, busbar detection module, regeneration circuit module, fan brake module, and current sampling module are located within detection area 130. These modules are arranged side by side from top to bottom and are connected to the signal terminals of the docking control board via corresponding isolation modules (not shown). An isolation strip 12 is provided between adjacent modules in the power supply module, surge isolation module, busbar detection module, regeneration circuit module, fan brake module, and current sampling module.

[0049] An isolation strip 13 is provided between adjacent lines connecting the current sampling module to the input terminal interface, the fan brake module to the input terminal interface, the busbar detection module to the input terminal interface, and the power module to the input terminal interface. An isolation strip 16 is provided between the line connecting the current sampling module to the MOS switch and the drive circuit.

[0050] The phase loss detection module, three-phase input protection module, bus filter module, power-on shock protection module, and rectifier module are located within the input filter protection area 110. The phase loss detection module and the three-phase input protection module are both located to the right of the input terminal interface, and the phase loss detection module and the three-phase input protection module are arranged sequentially from top to bottom. The three-phase input protection module is close to the power module and has an isolation zone 14 between it and the power module. The bus filter module and power-on shock protection module are located to the right of the phase loss detection module and the three-phase input protection module. The bus filter module and power-on shock protection module are arranged sequentially from top to bottom. The connection lines of the shock isolation module and the power-on shock protection module pass through the power module and have an isolation zone 15 between them. The rectifier module is located to the right of the bus filter module.

[0051] In conjunction with Figures 1 and 2, special attention should be paid to the following aspects of the layout:

[0052] First, the isolation between strong and weak circuits is achieved by using isolation belts for spatial isolation and isolation modules and chips (such as optocoupler modules) for circuit isolation.

[0053] The MOS switches T1, T4, T3, T6, T5, and T2 are plug-in devices and are located on the front side of the circuit board 100. The corresponding body diodes are placed on the back side of the circuit board 100 and are surface mounted devices.

[0054] The driver module is placed close to the MOS switch tube to achieve a shorter loop.

[0055] The busbar absorption capacitors C1, C2, and C3 are located in the driving area 140 and to the right of the MOS switches T1, T4, T3, T6, T5, and T2. The busbar absorption capacitors C1, C2, and C3 are polypropylene film axial plug-in capacitors. The busbar absorption capacitors C4, C5, and C6 are preferably ceramic chip capacitors and are placed close to the corresponding upper and lower bridge MOS switches to improve the effect of absorbing spikes. For example, the absorption capacitor C4 is placed close to the MOS switches T1 and T4, and the absorption capacitor C5 is placed close to the MOS switches T3 and T6. For example, the absorption capacitor C6 is placed close to the MOS switches T5 and T2. In other embodiments, the busbar absorption capacitors C1, C2, and C3 may not be provided.

[0056] The connection lines drawn from the UVW phases of the motor M and connected to the current sampling module are kept away from the drive module to prevent crosstalk interference.

[0057] The power supplies of the three upper bridge MOS switch tubes T1, T3, and T5 are separated by magnetic beads to reduce interference between power supplies.

[0058] In addition, the strong and weak electricity of the driver are isolated and separated, and the width of each isolation zone is not less than 2 mm, that is, the width of isolation zone 11, isolation zone 12, isolation zone 13, isolation zone 14, isolation zone 15 and isolation zone 16 is not less than 2 mm.

[0059] The upper bridge MOS switch tube T1 and the lower bridge MOS switch tube T4, the upper bridge MOS switch tube T3 and the lower bridge MOS switch tube T6, and the upper bridge MOS switch tube T5 and the lower bridge MOS switch tube T2 are separated, maintaining a spacing of at least 2 mm.

[0060] The shorter the drive line between the drive module and the corresponding MOS switch tube, the better, to reduce parasitic inductance.

[0061] Prioritize laying the outer copper layer on the PCB to handle the high current generated by the UVW phases of motor M. The current carrying capacity of the UVW phases of motor M is increased by laying the copper layer throughout the board, and evenly applying solder through windows in narrow areas to increase the current carrying capacity.

[0062] A weak current ground is set under the driver module, and a strong current ground is set under other modules connected to strong current.

[0063] The thermal ground area of ​​the drive module on the upper bridge should be small, leaving a safe distance between it and other roads.

[0064] The connection line that transmits the current acquisition signal generated by the current sampling module is far away from the connection line that transmits the drive signal generated by each module to prevent interference.

[0065] The 4-layer circuit board layout uses 2OZ copper thickness (maximum instantaneous current 50, continuous current 24A), the first layer is paved with P network, the second layer is paved with GND, the third layer is paved with V network, and the bottom layer is paved with N and W.

[0066] The foregoing descriptions of specific exemplary embodiments of the present invention are for the purpose of illustration and description. These descriptions are not intended to limit the invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings, and the invention can be implemented in other forms, structures, arrangements, proportions, and with other components, materials and parts. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different options and changes without departing from the scope and spirit of the present invention. The scope of the present invention is intended to be defined by the claims and their equivalents.

Claims

1. A PCB layout structure of a driver, characterized in that: include: A circuit board and an input terminal interface, a power module, an inverter module, an isolation chip, a plurality of drive modules and a docking control board signal terminal arranged on the circuit board; The circuit board is divided into an input filter protection area, a power supply area, a detection area and a drive area. The input terminal interface is arranged at one edge of the circuit board, the detection area is located on one side of the input terminal interface, the docking control board signal terminal is located on the other side of the detection area, the drive area is located on the other side of the docking control board signal terminal, the power supply area is located on one side of the input terminal interface and close to the detection area, and the input filter protection area is located on one side of the input terminal interface and close to the power supply area and the drive area; The inverter module is composed of multiple MOS switch tubes, the isolation chip, multiple MOS switch tubes and multiple drive modules are located in the drive area, the docking control board signal terminal is connected to the drive module through the isolation chip, the power module is located in the power area, and the power module is connected to the input terminal interface, the isolation chip and the drive module.

2. The PCB layout structure of the driver according to claim 1, characterized in that: The body diode of the MOS switch tube is located on the back side of the circuit board.

3. The PCB layout structure of the driver according to claim 1, characterized in that: An isolation zone is provided between the driving modules.

4. The PCB layout structure of the driver according to claim 1, characterized in that: The driver also includes an impact isolation module, a bus detection module, a regeneration circuit module, a fan brake module and a current sampling module arranged on the circuit board. The impact isolation module, the bus detection module, the regeneration circuit module and the fan brake module are located in the detection area. The impact isolation module, the bus detection module, the regeneration circuit module and the fan brake module are all connected to the signal terminal of the docking control board through the corresponding isolation module. There are isolation belts between the power supply module, the impact isolation module, the bus detection module, the regeneration circuit module, the fan brake module and the current sampling module.

5. The PCB layout structure of the driver as claimed in claim 4, characterized in that: There are isolation belts between the connection lines between the current sampling module and the input terminal interface, the connection lines between the fan brake module and the input terminal interface, the connection lines between the bus detection module and the input terminal interface, and the connection lines between the power supply module and the input terminal interface.

6. The PCB layout structure of the driver according to claim 1, characterized in that: The driver also includes a phase loss detection module, a three-phase input protection module, a bus filter module, an anti-power-on shock module and a rectifier module arranged on the circuit board, and the phase loss detection module, the three-phase input protection module, the bus filter module, the anti-power-on shock module and the rectifier module are located in the input filter protection area.

7. The PCB layout structure of the driver according to claim 6, characterized in that: The three-phase input protection module is close to the power module and has an isolation zone between the three-phase input protection module and the power module.

8. The PCB layout structure of the driver according to claim 1, characterized in that: The distance between the MOS switch tubes is not less than 2 mm.

9. The PCB layout structure of the driver according to claim 1, characterized in that: The driver includes an impact isolation module and an anti-power-on impact module arranged on a circuit board, the impact isolation module is located in a detection area, the anti-power-on impact module is located in an input filter protection area, and the connecting lines of the impact isolation module and the anti-power-on impact module pass through a power module and have an isolation zone between the power module.

10. The PCB layout structure of the driver according to claim 1, characterized in that: The driver further comprises a current sampling module arranged on the circuit board, and an isolation zone is provided between the connection line between the current sampling module and the MOS switch tube and the driving circuit.

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