Device, circuit board, circuit board assembly and electronic equipment

Abstract

The utility model discloses a device, a circuit board, a circuit board assembly and electronic equipment, the device is provided with a pin used for welding with the circuit board, the pin is provided with a welding section exposed out of a base, the length of the welding section is set to be greater than or equal to 1.5 mm, the length of the pin is set to be greater than or equal to 1.5 mm, a heat conduction path is increased, and the heat conduction efficiency is improved. The contact area between the pin and the copper sheet is increased, and the contact quality is improved, so that the reliability and the stability of a welding point are improved; and / or, the circuit board is provided with a copper sheet used for being welded with the device, and the width of the copper sheet is set to be less than or equal to 3mm, so that the width of the copper sheet is reduced, and on the premise of providing enough current transmission capability and meeting the requirement of welding quality, the copper sheet is prevented from sharing heat, so that the welding temperature of the pin of the large heat container device is improved, and the production efficiency is improved. The problem of how to ensure firm welding of the large heat container and the circuit board is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit board welding, in particular to a device, a circuit board, a circuit board assembly and an electronic device. Background Art

[0002] In the automotive field, customized functional integrated devices are required. Such devices exceed the application requirements of conventional SMD devices in terms of volume or weight. If they are made into SMD devices and placed on complex main power boards, especially during the surface mount soldering of large thermal capacitors, the solder joints between the soldering pins and the pads may be poorly formed or incomplete due to insufficient soldering temperature or insufficient soldering time. In this case, poor contact between the soldering pins and the pads may lead to unreliable electrical connections, resulting in the problem of cold soldering during soldering pin reflow.

[0003] The existing traditional solutions to the cold welding problem of SMD components are: ① If there are no heat-sensitive components on the single board and the number of components is small, the soldering reflow curve can be greatly improved to solve the cold welding problem; ② If there are a large number of materials on the single board and there are temperature-sensitive components, such as SMD relays, SMD electrolytic capacitors and other components, the range of adjusting the temperature curve is limited, and it is difficult to fundamentally solve the cold welding problem. At this time, the SMD material can be changed into a plug-in or the customized component can be soldered on a separate small board by changing the welding properties of the customized material. However, these two solutions often increase the cost of soldering and increase the cost and manufacturing fee of the small board. Utility Model Content

[0004] The main purpose of the utility model is to provide a device, a circuit board, a circuit board assembly and an electronic device, aiming to solve the problem of how to ensure that a large thermal capacitor is firmly welded to a circuit board under the premise of reducing production costs.

[0005] To achieve the above-mentioned purpose, the utility model provides a device, wherein the device is provided with a pin for welding to a circuit board, the pin has a welding section exposed from a base, and the length of the welding section is set to be greater than or equal to 1.5 mm.

[0006] The utility model provides a circuit board, on which a copper sheet for welding with a device is arranged, and the width of the copper sheet is set to be less than or equal to 3 mm.

[0007] Optionally, the circuit board is provided with a through slot, and the through slot is arranged beside the copper sheet.

[0008] Optionally, the copper sheets are provided in plurality, and the plurality of copper sheets are arranged at intervals;

[0009] There are a plurality of through slots, and each through slot is arranged between two adjacent copper sheets.

[0010] Optionally, each of the copper sheets extends in the longitudinal direction, a plurality of the copper sheets are arranged at intervals in the transverse direction, and each of the through grooves extends in the longitudinal direction.

[0011] Optionally, each of the through grooves is located at both ends in the longitudinal direction, and a plurality of protruding copper sheets are arranged at both ends in the longitudinal direction.

[0012] The utility model provides a circuit board assembly, which is characterized by comprising:

[0013] A circuit board, wherein a copper sheet is provided on the circuit board; and

[0014] A device, wherein the device is provided with pins, and the pins are welded to the copper sheet;

[0015] Wherein, the circuit board is set as the above-mentioned circuit board, and / or the device is set as the above-mentioned device.

[0016] Optionally, in two adjacently arranged devices, a distance between two pins that are closest to each other is greater than or equal to 5 mm.

[0017] The utility model provides an electronic device, which is characterized by comprising the above-mentioned circuit board assembly.

[0018] Optionally, the electronic device includes a power supply board.

[0019] In the technical solution provided by the utility model, the device is provided with a pin for welding with a circuit board. By increasing the length of the welding section of the pin and setting the length of the welding section of the pin to be greater than or equal to 1.5 mm, the path of heat conduction can be increased, so that heat can be more fully transferred to the circuit board, and the thermal contact between the pin and the copper skin of the circuit board can be improved, so that the welding temperature can be more uniform and sufficient; and increasing the length of the welding section of the pin can increase the contact area between the pin and the copper skin, improve the contact quality, and thus improve the reliability and stability of the welding point. It is also possible to reduce the width of the copper skin, and on the premise of providing sufficient current transmission capacity and meeting the requirements of welding quality, reduce the area of ​​the copper skin, avoid the copper skin from sharing heat, and reduce the pin welding temperature, so as to increase the pin welding temperature of the large thermal capacitor component and ensure the welding temperature, so as to solve the problem of how to ensure that the large thermal capacitor component is firmly welded to the circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0021] Figure 1 A schematic plan view of an embodiment of a circuit board assembly provided by the utility model;

[0022] Figure 2 It is a planar schematic diagram of a device in the prior art;

[0023] Figure 3 A schematic plan view of a device provided by the utility model;

[0024] Figure 4 It is a planar schematic diagram of a circuit board in the prior art;

[0025] Figure 5 A plan view of a circuit board provided by the utility model;

[0026] Figure 6 This is a plan view of another embodiment of the circuit board provided by the utility model.

[0027] Description of Figure Numbers:

[0028] Label name Label name 1 Devices 21 Copper Skin 11 Pinout a Through slot 2 Circuit Board 100 Circuit Board Assembly

[0029] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0033] In the automotive field, customized functional integrated devices are required. Such devices exceed the application requirements of conventional SMD devices in terms of volume or weight. If they are made into SMD devices and laid out on complex main power boards, especially in the surface mount soldering process of large thermal capacitors, the solder joints between the soldering pins and the pads are poorly formed or incomplete due to insufficient soldering temperature or insufficient soldering time. In this case, poor contact between the soldering pins and the pads may lead to unreliable electrical connections, resulting in the problem of cold soldering of soldering pins. The existing traditional solutions to the cold soldering problem of SMD devices are: ① If there are no thermal sensitive devices on the single board and the number of devices is small, the soldering reflow curve can be greatly improved to solve the cold soldering problem; ② If there are a large number of single board materials and there are temperature sensitive devices, such as SMD relays, SMD electrolytic capacitors and other devices, the range of adjusting the temperature curve is limited, and it is difficult to fundamentally solve the cold soldering problem. At this time, the SMD material can be changed into a plug-in or the customized device can be soldered on a separate small board by changing the welding properties of the customized material. However, these two solutions often increase the cost of soldering and increase the cost and manufacturing fee of the small board.

[0034] In order to solve the above problems, the utility model provides a device, a circuit board, a circuit board assembly and an electronic device. Figure 1 A schematic plan view of an embodiment of a circuit board assembly provided by the utility model; Figure 2 It is a planar schematic diagram of a device in the prior art; Figure 3 A schematic plan view of a device provided by the utility model;

[0035] Figure 4 It is a planar schematic diagram of a circuit board in the prior art; Figure 5 A plan view of a circuit board provided by the utility model; Figure 6 This is a plan view of another embodiment of the circuit board provided by the utility model.

[0036] See also Figure 2and Figure 3 The device 1 is provided with a pin 11, which is used for welding with the circuit board 2. The pin 11 has a welding section exposed from the base, and the length of the welding section is set to be greater than or equal to 1.5 mm.

[0037] It should be noted that the present invention is described by taking a power supply board as an example, and the device 1 is described by taking a surface mount auxiliary source transformer as an example.

[0038] Because the pins 11 of different devices 1 usually vary according to design requirements and device 1 packaging methods. The number and layout of pins 11 may vary to adapt to different applications and welding requirements. Therefore, the utility model does not limit the welding section of the pins 11 of all devices 1 to be set to be greater than or equal to 1.5 mm, but limits that when the device 1 is set as a patch auxiliary source transformer, the welding section of its pin 11 is set to be greater than or equal to 1.5 mm, which is longer than the length of the welding section of the pin commonly used in the prior art. Specifically, this can be achieved by reducing the base outline size of the device 1 and increasing the exposure of the welding pin 11.

[0039] It is understandable that the length of the welding section of the pin 11 can be set to 1.52 mm, 1.54 mm, 1.56 mm, 1.6 mm, 1.7 mm, etc.

[0040] It should also be noted that for common small devices 1 (such as chips, integrated circuits, etc.), the length of pin 11 is usually between several hundred microns (μm) and several millimeters (mm). For larger power devices 1 (such as power transistors, relays, etc.), the length of pin 11 is usually longer. This is to increase the spacing between pin 11 and circuit board 2 to accommodate larger currents and better heat dissipation. The length of pin 11 may be between several millimeters (mm) and tens of millimeters (mm). Therefore, the length of pin 11 is not limited to the above examples. Technicians in the relevant field may make other changes under the inspiration of the technical essence of the embodiments of this specification, but as long as the functions and effects achieved are the same or similar to the embodiments of this specification, they should be covered within the protection scope of the embodiments of this specification.

[0041] When welding the power supply board and the SMD auxiliary power transformer, the temperature of the solder paste needs to reach above 217 degrees. The device 1 with large thermal capacity will absorb heat itself, causing the temperature of the solder paste at the pin 11 to be less than 217 degrees, affecting the welding quality of the device 1.

[0042] In the technical solution provided by the utility model, a pin 11 for welding with a circuit board 2 is provided on the device 1. By increasing the length of the welding section of the pin 11 and setting the length of the welding section of the pin 11 to be greater than or equal to 1.5 mm, the heat conduction path can be increased, so that the heat can be more fully transferred to the circuit board 2, and the thermal contact between the pin 11 and the copper sheet 21 of the circuit board 2 can be improved, so that the welding temperature is more uniform and sufficient; and increasing the length of the welding section of the pin 11 can increase the contact area between the pin 11 and the copper sheet 21, improve the contact quality, thereby improving the reliability and stability of the welding point, so as to solve the problem of how to ensure that the large thermal capacitor device 1 and the circuit board 2 are firmly welded.

[0043] The utility model also provides a circuit board 2, see Figure 4 and Figure 5 The circuit board 2 is provided with a copper sheet 21 for welding with the device 1, and the width of the copper sheet 21 is set to be less than or equal to 3 mm.

[0044] It should be noted that copper has good thermal conductivity, and a larger copper sheet 21 area disperses the heat generated at the welding point. When the copper sheet 21 area is small, the heat conduction capacity is reduced, and the welding heat is concentrated in a smaller area, resulting in an increase in the temperature at the welding point; a smaller copper sheet 21 area may result in a reduction in the cross-sectional area through which the current passes, thereby increasing the current density at the welding point and causing the temperature at the welding point to increase.

[0045] In the technical solution provided by the utility model, by reducing the width of the copper sheet 21, the area of ​​the copper sheet 21 can be reduced while providing sufficient current transmission capacity and meeting the requirements of welding quality, thereby avoiding the copper sheet 21 from sharing heat, reducing the welding temperature of the pin 11, and increasing the welding temperature of the pin 11 of the large thermal capacitor 1.

[0046] It should be noted that in the prior art, the pin 11 of the device 1 is generally welded to the copper sheet 21 of the circuit board 2 by hot melt welding. During the hot melt welding process, the device 1 (such as a chip, a resistor, a capacitor, etc.) is first accurately placed on the circuit board 2 printed with solder paste, so that the pin 11 of the device 1 is aligned with the corresponding pad. Then the circuit board 2 is sent to the hot melt welding furnace, and the temperature in the furnace will gradually rise to above the melting point of the solder paste. When the solder paste melts, the flux will remove the oxides on the pad and the pin 11 of the device 1, and form an intermetallic compound with the copper sheet 21. Finally, cooling is performed to ensure that the solder joint is formed and solidified.

[0047] In order to transfer the high heat in the furnace to the circuit board 2 more efficiently and quickly, please refer to Figure 6In another embodiment, the circuit board 2 is provided with a through groove a, and the through groove a is arranged beside the copper sheet 21. Such arrangement allows the temperature in the furnace to be transferred to the upper side of the circuit board 2 through the through groove a, thereby promoting heat flow conduction and increasing the welding temperature of the pin 11 of the large thermal capacitor 1.

[0048] In this embodiment, a plurality of copper sheets 21 are provided, and the plurality of copper sheets 21 are arranged at intervals; a plurality of through slots a are provided, and each through slot a is provided between two adjacent copper sheets 21. In this way, the through slot a between two adjacent copper sheets 21 can simultaneously promote heat flow to the two copper sheets 21 and the pins 11 on both sides, so as to simultaneously increase the temperature at multiple welding points.

[0049] In this embodiment, each copper sheet 21 extends in the longitudinal direction, multiple copper sheets 21 are arranged at intervals in the transverse direction, and each through slot a extends in the longitudinal direction. It should be noted that the directions indicated by the longitudinal and transverse directions are not directions in an absolute sense. The directional indication is only used to explain a certain posture, such as when the length direction of the circuit board 2 is transverse, the width direction of the circuit board 2 is longitudinal. In this way, multiple copper sheets 21 are arranged in sequence in the transverse direction, which is convenient for the pins 11 of the device 1 to be aligned and soldered, and the through slot a is consistent with the extension direction of the copper sheet 21, which can well promote the conduction of heat flow, so that the solder paste of the copper sheet 21 in the longitudinal direction can be fully heated by the heat flow, so that the heating is uniform.

[0050] In other embodiments, the through groove a may also be configured to be S-shaped, I-shaped, or other shapes, which may be determined based on actual conditions and are not limited in this embodiment of the present specification.

[0051] Furthermore, in this embodiment, each through slot a is located at both ends in the longitudinal direction, and a plurality of copper sheets 21 are arranged at both ends in the longitudinal direction. In this way, the through slot a can not only correspond to the solder paste arrangement at various locations of the copper sheets 21 along the longitudinal direction to ensure the heat flow, but also conduct the heat flow to the vicinity of the two ends of the copper sheets 21 in the longitudinal direction. While ensuring that the temperature near the copper sheets 21 is uniform, the heat flow conduction effect on the upper and lower sides of the entire circuit board 2 is improved.

[0052] The utility model also provides a circuit board assembly 100, see Figure 1 , Figure 3 , Figure 5 and Figure 6 The circuit board assembly 100 includes a circuit board 2 and a device 1. The circuit board 2 is provided with a copper sheet 21. The device 1 is provided with a pin 11, and the pin 11 is welded to the copper sheet 21. In order to ensure that the large thermal capacitor device 1 and the circuit board 2 are welded firmly, the following forms can be adopted:

[0053] In the first embodiment, the circuit board 2 can be set as the above-mentioned circuit board 2, that is, the width of the copper sheet 21 of the circuit board 2 is reduced to reduce the area of ​​the copper sheet 21, avoid the copper sheet 21 from sharing heat, reduce the welding temperature of the pin 11, and increase the welding temperature of the pin 11 of the large thermal capacitor 1.

[0054] In the second embodiment, the device 1 is set as the above-mentioned device 1, that is, the length of the welding section of the pin 11 of the device 1 is increased to increase the heat conduction path, so that the heat is more fully transferred to the circuit board 2, the contact quality is improved, and thus the reliability and stability of the welding point are improved.

[0055] In the third embodiment, the width of the copper sheet 21 of the circuit board 2 can be reduced, and at the same time the length of the welding section of the pin 11 of the device 1 can be increased, so as to achieve a better welding effect.

[0056] Of course, in addition to taking the above measures, you can also fine-tune the reflow soldering curve and appropriately increase the soldering temperature. By comprehensively applying the above optimization measures, the soldering temperature of pin 11 can be increased from 217°C to 233°C, greatly reducing the risk of cold soldering of pin 11.

[0057] In the technical solution provided by the utility model, the length of the pin 11 is set to be greater than or equal to 1.5 mm, the heat conduction path is increased, the contact area between the pin 11 and the copper sheet 21 is increased, and the width of the copper sheet 21 is reduced. Under the premise of providing sufficient current transmission capacity and meeting the requirements of welding quality, the copper sheet 21 is prevented from sharing heat, so as to increase the welding temperature of the pin 11 of the large thermal capacitor 1.

[0058] In another embodiment, the distance between the two pins 11 closest to each other in two adjacent devices 1 is greater than or equal to 5 mm. This arrangement allows the device 1 to be arranged as far away from other devices 1 as possible, thereby further achieving the purpose of reducing welding heat loss.

[0059] The combination of the above technical features can achieve the goal of maintaining the soldering temperature of the pin 11 of the large thermal capacitor device 1 above the soldering temperature requirement (217°C) to ensure soldering quality. At the same time, it can avoid the need for a separate board or optimize the device 1 to be a plug-in. In comparison, it can save the production cost of a small board by 3.11 / pcs per board, or save the investment of at least one soldering equipment of 115W.

[0060] The utility model also provides an electronic device, which includes the above-mentioned circuit board assembly 100. Since the electronic device includes the circuit board assembly 100, the specific structure of the circuit board assembly 100 refers to the above-mentioned embodiment. Since the circuit board assembly 100 of the electronic device adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0061] Specifically, the electronic device includes a power supply board. The power supply board is a main component of an electronic device, which is used to provide power supply energy and manage the power supply system. The power supply board is usually an independent circuit board 2, which integrates functions such as power conversion, voltage regulation, current control and protection. Because the power supply board usually has functions and characteristics such as power conversion, voltage regulation, current control, overvoltage and undervoltage protection, temperature management and power management, a plurality of functional devices 1 are integrated on the circuit board 2. When the device 1 is set to a device 1 with large thermal capacity, the copper foil 21 of the circuit board 2 and the pin 11 of the device 1 adopt the above-mentioned structure to improve the contact quality, thereby improving the reliability and stability of the welding point, so as to solve the problem of how to ensure that the large thermal capacitance device 1 and the circuit board 2 are firmly welded.

[0062] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A circuit board, characterized in that: The circuit board is provided with a copper sheet for welding with the device, the width of the copper sheet is set to be less than or equal to 3 mm, and the circuit board is penetrated by a through groove, which is arranged beside the copper sheet.

2. The circuit board according to claim 1, characterized in that The copper sheets are provided in plurality, and the plurality of copper sheets are arranged at intervals; There are a plurality of through slots, and each through slot is arranged between two adjacent copper sheets.

3. The circuit board according to claim 2, characterized in that: Each of the copper sheets extends in the longitudinal direction, a plurality of the copper sheets are arranged at intervals in the transverse direction, and each of the through slots extends in the longitudinal direction.

4. The circuit board according to claim 3, characterized in that: Each of the through grooves is located at two ends in the longitudinal direction, and a plurality of protruding copper sheets are arranged at the two ends in the longitudinal direction.

5. A circuit board assembly, characterized in that: include: A circuit board, wherein a copper sheet is provided on the circuit board; and A device, wherein the device is provided with a pin, the pin is welded to the copper sheet, the pin has a welding section exposed from the base, and the length of the welding section is set to be greater than or equal to 1.5 mm; Wherein, the circuit board is configured as a circuit board as claimed in any one of claims 1 to 4.

6. The circuit board assembly according to claim 5, wherein: In two adjacently arranged devices, the distance between the two pins that are closest to each other is greater than or equal to 5 mm.

7. An electronic device, characterized in that: Comprising the circuit board assembly as claimed in claim 5 or 6.

8. The electronic device according to claim 7, characterized in that: The electronic device comprises a power supply board.

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