PCB packaging design method of SMT electronic component

Abstract

The invention discloses a PCB packaging design method for SMT electronic components, and relates to the technical field of electronic components, and the method comprises the steps: predetermining the packaging center-of-gravity position of each component, constructing an offset sensitivity coefficient through the packaging center-of-gravity position and the center position of a target glue point, and determining the allowable maximum offset through the combination of the maximum reflow soldering warped part angle, the maximum offset is allowed to be used for determining a qualified gum base; then, in the implementation stage of the dispensing equipment, determining a qualified glue base based on the allowable maximum offset; the method comprises the steps that firstly, a qualified gum base is obtained, then, an estimated component inclination angle is obtained based on the position corresponding to the qualified gum base, the estimated component inclination angle is used for identifying a PCB packaging design result and an early warning flag bit, the PCB packaging design result is used for summarizing related parameters meeting the inclination angle standard, and finally, when the early warning flag bit is triggered, compensation work of the PCB packaging design result is attempted to be conducted.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic components, and in particular to a PCB packaging design method for SMT electronic components. Background Art

[0002] SMT (surface mount technology) is the core process of modern electronic assembly. It generally uses electronic components to form interconnected circuits on the PCB surface through placement, printing, dispensing and reflow soldering. Especially in the process of high-density PCB packaging design, it is necessary to design the packaging layout and dispensing soldering scheme for various electronic components on the PCB to achieve the dual goals of mechanical fixation and electrical interconnection.

[0003] However, in the existing SMT electronic component packaging design and production practices, there is often a lack of accurate prediction and targeted design optimization methods for the problem of component warping caused by the offset of the glue points at the component packaging position on the PCB and the uneven wetting tension of the solder paste on both sides of the pad. Usually, the problem is only dealt with passively by improving the consistency of solder paste printing. For example, for some small QFN devices or power devices, there is a natural offset between the center of gravity of the package and the center of the target glue point. In addition, there is a slight difference in the volume of the solder paste on the left and right sides of the pad. When the reflow soldering melts to form a liquid wetting meniscus, a significant tension difference will be generated, which in turn generates unpredictable rotational torque, causing the device to warp before the reflow soldering cools and solidifies, and ultimately forming a welding defect that exceeds the specified inclination angle.

[0004] The resulting problem is that during the dispensing and reflow soldering hot melt stages, when the glue dot offset exceeds the allowable range or the fixed reaction force provided by the glue dot cannot effectively offset the rotational torque caused by the difference in wetting tension between the left and right pads, it will directly cause the electronic components to tilt beyond the allowable range during the reflow process, resulting in warping anomalies. Once the tilt angle exceeds the maximum process tolerance after reflow, the pins will not be fully soaked in solder, resulting in cold solder joints, or bridge short circuits will form in some areas, which will not only affect electrical performance, but may also cause cracks due to mechanical stress concentration, reducing the long-term reliability of the solder joints. For high-density packaging or sensitive devices, such anomalies are more likely to cause device performance drift or even batch failure, thereby increasing production scrap rates and subsequent rework costs. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a PCB packaging design method for SMT electronic components, which solves the problems in the above-mentioned background technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: A PCB packaging design method for SMT electronic components, comprising the following steps: Determine the package center of gravity of each component in advance, and construct the offset sensitivity coefficient based on the package center of gravity and the target glue point center position. Combined with the maximum reflow soldering warp angle, determine the maximum allowable offset. The maximum allowable offset is used to determine the qualified glue base. During the implementation phase of the dispensing equipment, the qualified glue base is determined based on the maximum allowable deviation; Based on the position corresponding to the qualified adhesive base, the estimated component tilt angle is obtained. The estimated component tilt angle is used to identify the PCB package design results and early warning flags. The PCB package design results are used to summarize the relevant parameters that meet the tilt angle standards. When the warning flag is triggered, an attempt is made to perform compensation work on the PCB package design results.

[0007] Preferably, the package shape parameters and position coordinates of each component on the PCB are obtained in advance, the package shape parameters including package body length, package body width, target glue point center position and maximum reflow soldering warp angle; Determine the package center of gravity of each component based on the package outline parameters; The offset sensitivity coefficient is constructed by the package center of gravity position and the target glue point center position, and the maximum allowable offset is determined by combining the maximum reflow soldering warp angle.

[0008] Preferably, the offset sensitivity coefficient is constructed by the package center of gravity position and the target glue point center position, and the maximum allowable offset is determined in combination with the maximum reflow soldering warp angle, including: Establish support lines through the contact points of component pins on the pads on both sides; S11: Establish a vector difference between the target glue point center position and the package gravity center position to obtain the designed eccentric distance; S12: During reflow soldering, obtain the wetting tension formed when the solder paste melts on both sides of the pad and the fixed counterforce provided by the glue point; S13: The torque generated by the designed eccentric distance is obtained by multiplying the designed eccentric distance by the fixed reaction force provided by the glue point; S14: Obtain the tension difference between the pads on both sides according to the wetting tension generated when the solder paste melts on both sides of the pad. Multiply the tension difference between the pads on both sides by the vertical distance from the pad to the center of gravity of the package to generate a rotational torque. S15: Obtain the total moment based on the equilibrium condition of plane rigid body statics; S16: Obtain the component inclination angle according to the total torque and package shape parameters; By randomly replacing the center position of the target glue point multiple times, multiple sets of designed eccentric distances are obtained, and the corresponding component inclination angles are obtained through S11 to S16. After numerical differentiation, the offset sensitivity coefficient is obtained; Among them, the offset sensitivity coefficient is used to analyze the incremental impact on the component's post-reflow tilt angle when the glue point offset changes; The maximum allowable offset is determined based on the maximum reflow soldering warp angle and the method for obtaining the offset sensitivity coefficient.

[0009] Preferably, during the implementation phase of the dispensing equipment, the qualified glue base is determined based on the maximum allowable deviation, including: During the implementation phase of the dispensing equipment, the actual dispensing position is monitored in real time, and the actual dispensing offset distance is determined in combination with the target glue point center position; The actual dispensing position is compared with the center position of the target glue point. If the actual dispensing offset distance does not exceed the maximum allowable offset, the actual dispensing position is taken as a qualified glue base. Otherwise, the adaptive path compensation program is triggered to readjust the dispensing coordinates until the actual dispensing offset distance does not exceed the maximum allowable offset. The dispensing coordinates are adjusted and a qualified glue base is obtained.

[0010] Preferably, S21: obtaining an estimated component tilt angle based on the position corresponding to the qualified adhesive base, including: According to the qualified glue base, determine the corresponding actual dispensing offset distance and mark it as the actual deviation; By obtaining the offset sensitivity coefficient, the offset sensitivity coefficient is multiplied by the actual deviation to obtain the estimated component tilt angle; Identify PCB package design results based on estimated component tilt angles.

[0011] Preferably, S22: identifying PCB package design results based on the estimated component tilt angle, including: If the estimated component tilt angle exceeds the maximum reflow soldering warp angle, the warning flag is triggered and an attempt is made to compensate for the PCB package design results. If the estimated component tilt angle does not exceed the maximum reflow soldering warp angle, the position and dispensing volume corresponding to the current qualified glue base will be used as the PCB package design results of the corresponding component and entered into the production process monitoring design library.

[0012] Preferably, when the warning flag is triggered, an attempt is made to perform compensation of the PCB package design result, including: To calculate the recommended dispensing volume, let the total moment be 0, that is, the equation , where is the wetting tension on the left side of the pad, is the wetting tension on the right side of the pad, is the vertical distance from the pad to the center of gravity of the package, Provides a fixed reaction force for the glue point, is the design eccentricity distance; Solving for variables , where the variable Indicates the fixed reaction force provided by the glue point; Determine the recommended dispensing volume based on the fixed reaction force provided by the solved glue point; If the recommended dispensing volume exceeds the upper limit of the dispensing volume, the upper limit of the dispensing volume is used as the compensation parameter of the current qualified glue base, and the PCB package design results of the corresponding components are analyzed again. Otherwise, the position corresponding to the current qualified glue base and the PCB package design results of the components corresponding to the recommended dispensing volume are input into the production process monitoring design library.

[0013] Preferably, if the recommended dispensing volume exceeds the upper limit of the dispensing volume, the upper limit of the dispensing volume is used as the compensation parameter of the current qualified glue base, and the PCB package design results of the corresponding components are analyzed again, including: According to the compensation parameters of the current qualified glue base, the fixed reaction force provided by the glue point is reversed and substituted into the equation , re-execute S15 and S16 to determine the corresponding component inclination angle under the upper limit of the dispensing volume; If the corresponding component tilt angle does not exceed the maximum reflow soldering warp angle under the upper limit of the dispensing volume, the position corresponding to the current qualified glue base and the recommended dispensing volume will be used as the PCB package design result of the corresponding component and entered into the production process monitoring design library; If the corresponding component inclination angle exceeds the maximum reflow soldering warp angle under the upper limit of the dispensing volume, the adaptive path compensation program is triggered again, the dispensing coordinates are adjusted again, a qualified glue base is obtained, and S21 and S22 are repeated to obtain the PCB package design results of the corresponding components.

[0014] The present invention provides a PCB packaging design method for SMT electronic components, which has the following beneficial effects: (1) The package center of gravity position of each component is determined in advance, and the offset sensitivity coefficient is constructed based on the geometric relationship between the package center of gravity position and the target glue point center position. Combined with the maximum allowable offset obtained by scientific calculation of the maximum reflow soldering warp angle, the acceptable range of glue point position offset can be accurately defined in the design stage, and a clear process window can be provided for the subsequent actual production process. In the implementation stage of the dispensing equipment, based on the above-mentioned maximum allowable offset, it is possible to quickly and effectively determine whether the actual dispensing position meets the requirements of the qualified glue base, avoiding the potential warp risk caused by excessive glue point offset, and further improving the coordination and consistency between the PCB package design and the dispensing path. When the detection finds that the actual dispensing offset exceeds the maximum allowable offset and triggers the warning flag, the system can automatically perform the compensation operation of the PCB package design result, and correct the potential imbalance caused by the dispensing offset in real time by intelligently adjusting the dispensing coordinates, dispensing volume or other compensation parameters, ensuring that the actual inclination angle of the component after reflow soldering can still meet the requirements of the maximum reflow soldering warp angle under the condition of the coupling balance of dispensing volume, glue point offset and pad tension. Therefore, through the above-mentioned comprehensive technical measures, the present invention can improve the reliability and consistency of PCB packaging design, reduce electrical solder joints, mechanical interference or rework rates caused by excessive warping of parts, and provide a qualified glue base and packaging geometry database for post-production process monitoring, effectively forming a closed-loop optimization of design-process-testing, and improving the quality level and production yield of the entire machine.

[0015] (2) Obtain the package outline parameters and PCB coordinates through the package specification, and then calculate the package center of gravity position, and establish the offset sensitivity coefficient based on the target glue point center. Then, based on the maximum reflow soldering warp angle, scientifically determine the maximum allowable offset, which can effectively quantify the impact of glue point offset on the post-reflow tilt angle. By establishing support lines, calculating the design eccentric distance, and solving the rotation torque and tilt angle through wetting tension and fixed reaction force, the risk of component warp under glue point offset is comprehensively evaluated. This method further solves the problem that it is difficult to quantitatively analyze the warp anomaly caused by glue point offset in existing SMT package design, and it is difficult to determine the maximum offset limit based on experience alone. It ensures that each component still meets the maximum warp angle requirement under multiple offset simulations, reduces the risk of cold solder joints, interference and electrical failure, and improves the reliability and consistency of PCB package design from the source.

[0016] (3) During the implementation phase of the dispensing equipment, the present invention monitors the actual dispensing position in real time and compares it with the target dispensing center position to determine whether the actual dispensing offset distance exceeds the pre-calculated maximum allowable offset. If it exceeds the limit, the adaptive path compensation program is automatically triggered to adjust the dispensing coordinates in real time until the offset is controlled within the allowable range, thereby determining a qualified glue base. Compared with the existing technology that generally relies on manual sampling and post-correction, which can easily lead to uncontrollable offset, the present method realizes closed-loop adaptive adjustment of the dispensing process by combining the maximum offset angle and the offset sensitivity to establish an offset threshold, so that the actual dispensing position is always controlled within the safe range, effectively avoiding component offset out-of-tolerance, cold solder joints and subsequent rework caused by excessive dispensing offset, and improving the consistency of PCB packaging and the reliability of finished products.

[0017] (4) Based on the qualified glue base position, the estimated component tilt angle is calculated by combining the offset sensitivity coefficient and the actual deviation, and compared with the maximum reflow soldering warp angle to identify the PCB package design results in real time. When the estimated tilt angle exceeds the limit, an early warning is automatically triggered and a compensation operation is started. If it does not exceed the limit, key parameters such as the qualified glue base and dispensing volume are written into the production process monitoring design library to form a traceable standard packaging template. Compared with the existing method that relies on post-AOI inspection and rework, it is difficult to prevent the problem of warping in the dispensing-packaging link in a timely manner. This method effectively screens out potential warping risks in advance during the design stage through tilt angle prediction and closed-loop verification, and provides relatively better data reference for the subsequent packaging of similar products. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a flow chart of a PCB packaging design method for SMT electronic components according to the present invention; Figure 2 This is a logic diagram of a PCB packaging design method for SMT electronic components of the present invention. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] Example 1 See also Figure 1 and Figure 2 The present invention provides a PCB packaging design method for SMT electronic components, comprising the following steps: A1: Determine the center of gravity of each component package in advance, and construct the offset sensitivity coefficient based on the center of gravity of the package and the center of the target glue point. Combined with the maximum reflow soldering warp angle, determine the maximum allowable offset. The maximum allowable offset is used to determine the qualified glue base. A2: During the dispensing equipment implementation phase, determine the qualified glue base based on the maximum allowable deviation; A3: Based on the position corresponding to the qualified adhesive base, the estimated component tilt angle is obtained. The estimated component tilt angle is used to identify the PCB package design results and early warning flags. The PCB package design results are used to summarize the relevant parameters that meet the tilt angle standards. A4: When the warning flag is triggered, attempt to perform compensation work on the PCB package design results.

[0021] Depend on Figure 2 It can be seen that the operating instructions therein contain the contents of the dispensing operating instructions. The content of this application is to encapsulate and design the operations in this part in order to improve and optimize the contents of the dispensing operating instructions.

[0022] In this embodiment, in A1, the package length, package width, and recommended glue dispensing center position are first obtained by reading the component package specification or a three-dimensional package library (e.g., JEDEC package data). The package center of gravity coordinates are then derived from this. A vector difference is then established between the package center of gravity and the target glue point center position to construct an offset sensitivity coefficient, which is used to quantify the impact of glue point offset on the component's post-reflow warpage angle. For example, a large γ value indicates that a slight offset of the glue point relative to the package center of gravity will significantly amplify the post-weld warpage angle, suggesting that offset must be strictly controlled in subsequent process design. The logic of this step is to pre-quantify the causal relationship between offset and warpage, and then, in combination with the maximum allowable warpage angle, use γ to infer the maximum allowable offset, thereby clarifying the acceptable glue dispensing offset tolerance for the glue dispensing equipment.

[0023] In the actual dispensing stage A2, the dispensing position is monitored in real time through high-speed visual recognition (for example, the dispensing AOI detects the coordinates of each glue point) and compared with the center position of the target glue point. If the actual dispensing offset distance does not exceed the maximum allowable offset, the glue point can be determined to be a qualified glue base. Otherwise, the adaptive path compensation program is triggered (such as automatic correction of the dispensing path) and the dispensing coordinates are re-adjusted until the conditions are met. For example, for a QFN device with a package size of 3.2×1.6mm, the maximum allowable offset is calculated to be 20μm. If the actual offset detected by the dispensing AOI is 18μm, it is determined to be a qualified glue base. The beneficial logic of this step is that by converting the offset tolerance into a production equipment judgment threshold, online real-time closed-loop control of the glue point position quality is achieved. However, it should be noted that the qualified glue base here only represents a position that can be used as a glue point, but it does not mean that dispensing at this position will not cause warping in the later stage. In A3, after obtaining the qualified glue base, the offset sensitivity coefficient γ is combined with the estimated tilt angle to quickly evaluate the potential tilt angle of the qualified glue base after reflow soldering. For example, if γ = 0.5° / μm and the actual offset is 18μm, the estimated tilt angle = 9°, which is significantly higher than the allowable upper limit of 5°. At this time, the early warning flag is immediately triggered to guide the next compensation process; on the contrary, if the estimated tilt angle is ≤5°, the current dispensing coordinates and dispensing volume are written into the process monitoring database as the PCB package design results for subsequent mass production standardization. This can avoid the direct use of unoptimized packages in mass production and reduce the risk of non-conformity.

[0024] In A4, when a warning is triggered, the equilibrium torque equation is solved, setting the rotational torque to 0. This derives the fixed reaction force required for the glue point, and inversely calculates the recommended glue volume GV. If the recommended GV does not exceed the upper limit allowed by the equipment, it is used as the new package design result. If it does, the estimated tilt angle is recalculated using the maximum allowable glue volume as the compensation parameter to determine whether it meets the standard. If it still exceeds the limit, path compensation is triggered again to fine-tune the glue coordinates. The logical significance of this step is that through multiple iterative compensations, the component tilt angle does not exceed the maximum reflow soldering warp angle. This ensures that no matter how the glue point position or volume is fine-tuned, a solution that meets the warp standard can be obtained during the package design phase, forming a closed-loop self-repair system. Therefore, through the above steps, the method provided by the present invention not only realizes precise quantitative control based on the relationship between the package center of gravity and the glue point center, but also enables the PCB packaging design of SMT electronic components to have predictability, traceability and adaptive optimization characteristics through the collaboration of multiple units such as thresholding of maximum offset, real-time glue point offset detection, estimated inclination angle and closed-loop compensation, effectively solving the prominent problems of reliance on experience, uncontrollable deviations and batch defects in the existing technology, and improving the welding quality and the reliability of the whole machine.

[0025] It should be noted that dispensing refers to the process of applying a precise amount of glue (such as epoxy resin, UV glue or conductive glue) to a specific location on the PCB board to fix, protect or conduct components. Its purpose is to fix the components.

[0026] Example 2 Please refer to Figure 1 Specifically: Through the package specification, the package parameters and position coordinates of each component on the PCB are obtained in advance. The package parameters include package length, package width, target glue point center position and maximum reflow soldering warp angle; In industrial practice, the recommended glue point is usually not equal to the package center of gravity for the following reasons: Pad layout limitation: The bottom of the components is often left empty due to pin arrangement. For example, QFP has pads on all sides and an empty space in the middle. If glue is applied directly at the center of gravity, the glue may squeeze under the pad, contaminating the pad and causing cold solder joints. Glue dispensing manufacturability requirements: The nozzle of the SMT dispensing machine has a fixed size (for example, 0.3-0.5mm inner diameter). For multi-pin packages, it is necessary to avoid glue hitting fine-pitch pads. Therefore, it is usually recommended that the glue point be offset to a position that is less likely to contaminate the pad, even if it is slightly away from the geometric center of gravity.

[0027] The soldering pad is a "metal area" made of copper foil on the PCB, which is used to solder the component pins.

[0028] Based on the package shape parameters, determine the package center of gravity position of each component (i.e. the package geometric center); All ICs, inductors, capacitors, crystal oscillators and other components are shipped with a PDF specification sheet, which contains the package mechanical dimensions, usually indicating: package length, package width, etc. For symmetrical packages: directly use the midpoint of the package length and width to determine the package center of gravity. For asymmetric packages (such as pins of different lengths, special-shaped large inductors): perform a "mass center" analysis in 3DCAD or packaging software, or use "Centroid" coordinates to automatically generate in the package library. Centroid is the package geometric center coordinate, also called "center of mass coordinate" or "device center point coordinate."

[0029] The offset sensitivity coefficient is constructed based on the package center of gravity position and the target glue dot center position. This is used to analyze the incremental impact of changes in the glue dot offset (i.e., the difference between the package center of gravity position and the target glue dot center position) on the component's post-reflow tilt angle. The maximum allowable offset is determined in combination with the maximum reflow soldering warp angle.

[0030] The offset sensitivity coefficient is constructed by the package center of gravity position and the target glue point center position, and combined with the maximum reflow soldering warp angle, the maximum allowable offset is determined, including: Establish support lines through the contact points of component pins on the pads on both sides; S11: Establish a vector difference between the target glue point center position and the package gravity center position to obtain the designed eccentric distance, specifically: ,in, To design the eccentric distance, is the center position of the target glue point, is the center of gravity of the package; S12: During reflow soldering, obtain the wetting tension formed when the solder paste melts on both sides of the pad and the fixed counterforce provided by the glue point; The wetting tension formed when the solder paste melts on both sides of the pad refers to the formation of liquid solder on the pad after the solder paste melts during reflow soldering, resulting in a typical wetting meniscus and generating tension along the interface.

[0031] The fixed counterforce provided by the glue point is that when the component is pulled or floated by the surface tension of the solder paste during reflow soldering, the glue point will resist the upward force like a "spring", preventing the component from tilting or moving; During SMT reflow soldering, when the solder paste is heated and melted into liquid solder, a wetting meniscus is formed on the surface of the pad. This wetting meniscus exerts tension between the component and the PCB through the surface tension of the liquid metal. If the left and right pads have different wetting areas or wetting angles due to eccentric dispensing or different solder paste volumes, the tension on the left and right pads will be unbalanced, which will generate a rotational torque and cause the component to warp. Therefore, the tension (wetting tension) generated by the left and right pads needs to be calculated separately. The specific calculation is obtained using the following formula: , ,in, is the wetting tension on the left side of the pad, is the wetting tension on the right side of the pad, is the unit volume wetting tension coefficient (N / ), can be fitted through historical reflux data, is the volume of the solder paste on the left pad after melting, The volume of the solder paste on the right pad after melting; In real wetting theory (Young-Dupré equation, meniscus tension equation), ,in, is the wetting tension on the corresponding side of the pad, is the solid-liquid interfacial tension, is the wetted length, is the wetting contact angle, and the wetting length itself depends on the spread of the liquid solder volume (the volume of the melted solder paste on the corresponding side pad). After multiple experimental statistics, it was found that for the same type of solder, PCBs with similar pad surface energy, and similar reflow curves, the wetting length and volume can often be fitted linearly or sublinearly. In the same factory / same batch, it can be directly empirically converted to , ; S13: The torque generated by the designed eccentric distance is obtained by multiplying the designed eccentric distance by the fixed reaction force provided by the glue point. Specifically, it is: ,in, is the torque, Provides a fixed reaction force for the glue point, is the design eccentric distance; its formula comes from the classic plane moment formula: M=F*L, where F is force and L is distance; It indicates the fixed counter torque generated by the glue point deviating from the package, which can be changed by adjusting the glue point volume. ,control size.

[0032] S14: Based on the wetting tension generated when the solder paste melts on both sides of the pad, the tension difference between the pads on both sides is obtained. The rotational torque is generated by multiplying the tension difference between the pads on both sides by the vertical distance from the pad to the center of gravity of the package. Specifically, it is: ,in, is the rotational torque, is the wetting tension on the left side of the pad, is the wetting tension on the right side of the pad, is the vertical distance from the pad to the center of gravity of the package; this formula is based on the difference in tension caused by wetting tension on different pads , multiplied by the vertical distance h (the height from the pad to the center of gravity of the package), forms a rotational torque around the center of the package, which is still the classic plane torque formula, except that F here is the resultant force generated by the wetting tension difference; It refers to the rotational torque generated by the wetting tension difference formed by the melted solder paste on the left and right sides of the pad. If there is no other force (such as glue), the component will rotate and warp due to this tension difference.

[0033] S15: Based on the equilibrium condition of plane rigid body statics, obtain the total torque, specifically: , where M is the total moment; During reflow soldering, the melted solder paste on both sides of the pad forms a wetting meniscus, which generates a tension that pulls outward. If the tension on the left is greater than that on the right, a torque will be generated to flip the device to the right. However, due to the eccentricity of the glue dot (the center of the glue dot does not coincide with the center of mass of the package), the glue is pulled or pressed, which will generate a fixed reaction force and form a torque at the eccentric distance. However, the direction of this torque is different from the Instead, it is trying to pull the device back to stop it from flipping, so when equilibrium is reached (no further rotation), the total torque is 0. ; S16: Obtain the component inclination angle based on the total torque and package shape parameters, specifically: ,in, is the component inclination angle, is the rotational inertia moment of the package relative to the support line, and M is the total moment; The rotational inertia moment of the package relative to the support line is the geometric bending stiffness of the package when it rotates around its support edge (the contact line of the pads on both sides). For typical SMT packages (ICs, inductors, capacitors), they are usually rectangular. If the package is rotated around the support line (the support line is usually between the centers of the pads on both sides of the bottom surface of the package), the cross section of the package can be approximated by a rectangle. It can be estimated by analogy with the moment of inertia of the beam bending stiffness: , where BL is the length of the package bottom along the support line (e.g., the pin layout direction), and BH is the package height. This formula is actually directly derived from the classic theory of the moment of inertia (geometric moment of inertia) of a plane rigid body, also known as the "quadratic moment of inertia" in mechanics. For a rectangular cross-section, the formula for the moment of inertia about its bottom axis is: , where B is the length parallel to the axis of rotation (i.e., along the support line), and hz is the height perpendicular to the axis of rotation. In SMT lift components, this is replaced by: the length of the package bottom surface along the support line (such as the pin arrangement direction) BL and the package height BH. In short, this formula is directly derived from the rectangular cross-section plane moment of inertia theory of material mechanics. It is used to describe the geometric anti-warping ability of the SMT package when rotating around the support line. It is the standard moment of inertia calculation model in the tension-fixation-rotation analysis of SMT lift components.

[0034] By randomly replacing the target glue point center position multiple times, multiple sets of design eccentric distances are obtained. Then, through S11 to S16, the corresponding component tilt angles are obtained (the corresponding component tilt angles do not exceed the maximum reflow soldering warp angle). After numerical differentiation, the offset sensitivity coefficient is obtained, which is specifically: ,in, is the offset sensitivity coefficient, is the partial derivative, For a small amount of element tilt change, that is, when When a small change occurs, the component tilt the tiny increments that will occur; is a small amount of glue point offset change, that is A small increment as a variable for glue dot offset; The offset sensitivity coefficient indicates the offset of the glue point relative to the center of gravity of the package. When slight changes occur, the tilt angle of the component after reflow soldering If the rate of change Very big, description A slight increase will make Increase a lot, if If it is very small, it means that the package (i.e. component) is not sensitive to glue point offset; The maximum allowable offset is determined based on the maximum reflow soldering warp angle and the method for obtaining the offset sensitivity coefficient. Specifically: ,in, To allow for maximum offset, The maximum reflow soldering warping angle; In this embodiment, first, the method obtains the package shape parameters of each component (for example, the package body length is 4.5 mm, the package body width is 3.2 mm) and its pre-arrangement coordinates on the PCB from the package specification sheet in advance, and can also obtain the design coordinates of the target glue point center and the maximum reflow soldering warp angle allowed by the product process (for example, ≤5°).

[0035] Based on these package outline parameters, geometric calculations are further used to determine the package's center of gravity, which serves as a benchmark for describing the equilibrium point of the component's overall mass distribution. For example, for a QFN package with pins evenly distributed on both sides, the center of gravity is located at the package's geometric center. For a package with a special-shaped thermal pad, the center of gravity may be biased to one side. This processing logic based on package geometry and center of gravity helps clarify component force and rotational characteristics early in the design process, avoiding trial and error caused by blindly adjusting dispensing or solder paste later.

[0036] Subsequently, support lines are established through the contact points of the component pins on the pads on both sides to represent the force axis of the component on the pad. On this basis, an analysis closed loop is formed through the following steps: S11: Calculate the design eccentricity distance, establish a vector difference between the center position of the target glue point and the center of gravity position of the package, and obtain the design eccentricity distance. For example, if the coordinates of the package's center of gravity are (2.25, 1.6) mm, and the target glue dot's center position is (2.35, 1.6) mm, the designed eccentric distance is 0.1 mm, indicating that the glue dot is slightly to the right. S12-S14: Calculate various moments. During the reflow process, obtain the wetting tension formed by the melted solder paste on both sides of the pad. Multiply the designed eccentric distance by the fixed reaction force provided by the glue dot to obtain the eccentric fixed moment. Multiply the wetting tension difference on both sides of the pad by the vertical distance from the pad to the package's center of gravity to obtain the rotational torque. Through these steps, the total moment M can be calculated based on the moment balance equation (S15). Combined with the package's rotational moment of inertia in S16, the component's inclination angle during reflow can be obtained. This method of establishing static equilibrium conditions through support lines and detailed decomposition of the various moments formed by the wetting tension and eccentric fixed reaction force can scientifically quantify the extent to which the glue dot offset affects the inclination angle.

[0037] The reflow soldering process involves placing the PCB into a reflow oven, where the solder paste melts and completes the electrical soldering process. At this point, the pre-cured (or reflow-cured) adhesive continues to hold the components in place, preventing them from floating or lifting.

[0038] In the SMT dispensing and reflow soldering process, the main purpose of glue is to mechanically adsorb components to the PCB before the solder paste melts. Offset glue points will only secure components from one side or one corner. For example, the glue should have been dispensed directly below the center of a capacitor, but now it is offset to the left. As a result, the "adsorption force" on the component mainly comes from the glue on the left, and the right side lacks balance support. During the reflow stage, the solder paste begins to heat up and melt, the humid gas expands, and finally the surface tension is redistributed. At this time, the solder paste will generate a certain pulling force (wetting force) to pull the component to the center. If the glue is biased to one side, it is equivalent to the left side being strongly "glued" and the right side having no adhesion, which will cause warping. In addition, the component itself expands unevenly due to heat, and will also "warp up" when the center of gravity is biased. If the solder joints on both sides are heated slightly out of sync, the side that melts first will flip upwards due to the lack of symmetrical glue resistance. Therefore, the offset glue dispensing is equivalent to creating an "eccentric" support at the bottom of the component. During reflow, if the surface tension of the solder paste changes or the component expands slightly out of sync due to heat, torque will occur, causing the end not fixed by glue to be "lifted" upwards, forming a warped component (or tombstoning effect).

[0039] Based on the balance analysis model established above, the target glue point center position is randomly replaced multiple times (for example, a new glue point position is generated in steps of ±0.02mm each time), and steps S11-S16 are repeated to obtain the change in component tilt angle under different glue point offsets. The offset sensitivity coefficient is obtained through numerical differentiation, indicating how much the tilt angle of the component will change after reflow soldering when a small glue point offset occurs. For example, if γ = 12, then a glue point offset of 0.01mm will result in an increase in tilt angle of 0.12°, which is highly sensitive. Combined with the maximum allowable reflow soldering tilt angle (for example, 5°), the maximum allowable offset (e.g., approximately 0.42mm) can be calculated. This allows the PCB to scientifically determine the allowable glue point coordinate offset window during the design phase, further reducing the risk of component tilt caused by glue point offset in the later stages.

[0040] The specific logical closed loop achieved through the above-mentioned technical means can not only predict the position tolerance of glue dots during the PCB design stage, but also avoid over-deviation through real-time monitoring and compensation of the glue dispensing equipment during the production stage, thereby quickly forming a qualified glue base. When a slight abnormality occurs (such as slightly larger eccentricity), the system can calculate the estimated inclination angle in real time based on the offset sensitivity coefficient and compare it with the maximum reflow soldering warp angle. If the limit is exceeded, compensation will be triggered, thereby effectively avoiding the serious consequences of pin cold soldering, open circuit or component jamming caused by excessive warping, further improving the reliability of the SMT process and the subsequent assembly yield.

[0041] Example 3 Please refer to Figure 1 ,Specifically: During the implementation phase of the dispensing equipment, the qualified glue base is determined based on the maximum allowable deviation, including, During the implementation phase of the dispensing equipment, the actual dispensing position is monitored in real time, and the actual dispensing offset distance is determined in combination with the target glue point center position; The glue dispensing process is carried out using a glue dispenser, which operates on a precise fluid control and mechanical transmission system. Its core principle is to precisely and steadily deliver glue from the glue storage barrel to the dispensing needle using compressed air to drive a piston or screw pump. Specifically, when compressed air enters the glue bottle, it exerts pressure on the glue, pushing it into a feed tube connected to a piston chamber. The air pressure then causes the piston to move up and down. When the piston rises, the piston chamber is filled with glue; when the piston descends, the glue is precisely squeezed out of the needle under pressure.

[0042] The actual dispensing position is compared with the center position of the target glue point. If the actual dispensing offset distance does not exceed the maximum allowable offset, the actual dispensing position is taken as a qualified glue base. Otherwise, the adaptive path compensation program is triggered to readjust the dispensing coordinates until the actual dispensing offset distance does not exceed the maximum allowable offset. The dispensing coordinates are adjusted and a qualified glue base is obtained.

[0043] In this embodiment, first, the actual dispensing coordinates are monitored by the dispensing machine vision or position encoder, and the actual dispensing offset distance is obtained by combining the pre-planned target dispensing center position. For example, if the desired dispensing location is (X=12.5, Y=8.0), but the actual location is (12.7, 7.9), the offset ΔC can be calculated as mm, then compare the actual offset distance with the maximum allowable offset. If the offset is ≤ the maximum tolerance (for example, the maximum allowable offset is 0.3mm), the actual dispensing position is determined to be a qualified glue base; otherwise, if it exceeds, such as the offset is 0.35mm, the adaptive path compensation program is triggered to automatically fine-tune the dispensing head trajectory (for example, adjust to X=12.6, Y=8.0), and repeat the test; The qualified glue base in this process refers to the actual dispensing position whose offset does not exceed the maximum tolerance, ensuring that the subsequent components are subjected to symmetrical forces and avoiding reflow warping. Adaptive path compensation is used to dynamically correct the dispensing coordinates so that the production process can quickly return to a qualified state after a slight cumulative deviation. This method effectively reduces the risk of over-limit warping caused by dispensing drift through closed-loop judgment and real-time compensation, thereby improving production consistency and welding reliability.

[0044] Example 4 Please refer to Figure 1 ,Specifically: S21: Based on the position corresponding to the qualified glue base, obtain the estimated component inclination angle, including, According to the qualified glue base, determine the corresponding actual dispensing offset distance and mark it as the actual deviation; By obtaining the offset sensitivity coefficient, the offset sensitivity coefficient is multiplied by the actual deviation to obtain the estimated component tilt angle; Identify PCB package design results based on estimated component tilt angles.

[0045] S22: Based on the estimated component tilt angle, identify the PCB package design results, including: If the estimated component tilt angle exceeds the maximum reflow soldering warp angle, the warning flag is triggered and an attempt is made to compensate for the PCB package design results. If the estimated component tilt angle does not exceed the maximum reflow soldering warp angle, the position and dispensing volume corresponding to the current qualified glue base will be used as the PCB package design results of the corresponding component and entered into the production process monitoring design library.

[0046] The production process monitoring design library refers to the collection of relevant parameters that meet the tilt angle standard (not exceeding the maximum reflow soldering warp angle) to provide reference materials for the subsequent PCB board package design; In this embodiment, first in S21, based on the determined qualified glue base position, the actual glue dispensing offset distance is determined (for example, 0.08mm away from the center of the target glue point), and the distance is marked as the actual deviation; then, the offset sensitivity coefficient (for example, γ = 20° / mm) that has been obtained is multiplied by the actual deviation to quickly calculate the estimated component tilt angle (here the estimated component tilt angle = 1.6°). Among them, the offset sensitivity coefficient is a key parameter that quantitatively describes the degree of influence of a small offset in the glue point position on the change in the tilt angle of the component after reflow soldering, and is used for sensitivity estimation. Subsequently, in S22, by comparing with the maximum reflow soldering warp angle (for example, 5°), if the estimated tilt angle does not exceed the maximum reflow soldering warp angle, the current qualified glue base position, glue dispensing volume, and offset data are directly used as the PCB package design result of the component, and stored in the production process monitoring design library (for example, recorded as {glue base coordinates: (x, y), glue dispensing volume: 0.18 , estimated component tilt angle: 1.6°}), providing traceable data for subsequent similar PCB packages; conversely, if the estimated tilt angle exceeds the maximum reflow soldering warpage angle (for example, the calculated estimated component tilt angle = 6.3°), the warning flag is immediately triggered, and the compensation operation of the subsequent PCB package design results is started. In this way, by utilizing the sensitivity-based real-time tilt angle estimation and compliance judgment process, the present invention can dynamically determine whether the package design is out of tolerance through a small amount of calculation in production, and integrate the qualified data into the monitoring database, effectively avoiding the return of warped parts due to out-of-tolerance, and supporting subsequent process optimization and experience callback, to achieve closed-loop quality control from design to mass production.

[0047] For example, during the implementation of the PCB dispensing process for a certain type of QFN package, based on the package specification and the calculation in the previous steps, it is known that its offset sensitivity coefficient γ=2.5 (indicates that every 0.01mm offset will cause a 0.025° tilt angle change). Through real-time detection, it is found that the actual dispensing offset distance ΔC=0.03mm after the current qualified glue base is dispensed. Therefore, it is calculated through the offset sensitivity formula: estimated tilt angle = γ×ΔC=2.5×0.03=0.075°, and then the estimated tilt angle is compared with the maximum allowable reflow warping angle of 0.5° for the package in S22. It can be seen that 0.075°<0.5°, so it is determined to meet the requirements. Then the system calculates the position of this qualified glue base (such as X=20.12, Y=15.06), the dispensing volume (such as 0.25 ) and the corresponding package model parameters are written into the production process monitoring design library, providing a standard package data template that can be directly referenced for subsequent batch production of the same series of PCBs. If the calculated result in this example predicts an inclination angle greater than 0.5°, a warning flag is triggered, automatically entering the next round of PCB package compensation, and re-adjusting the dispensing coordinates and volume parameters until the inclination angle requirements are met.

[0048] Example 5 Please refer to Figure 1 ,Specifically: When the warning flag is triggered, attempt to perform compensation work on the PCB package design results, including, To calculate the recommended dispensing volume, let the total moment be 0, that is, the equation , solving for the variable , where the variable Indicates the fixed reaction force provided by the glue point; in, It is the rotation torque caused by the difference in wetting tension between the left and right pads. This is because the glue point deviates from the center position of the target glue point and the rotational torque generated by the glue fixing force.

[0049] So this equation ( The physical meaning of ) is that the tension difference of the pad causes the component to warp to one side, and the eccentric fixing force provided by the glue will produce a reverse torque. After the two cancel each other out, they reach a balance and no longer rotate.

[0050] Based on the fixed reaction force provided by the solved glue point, the recommended dispensing volume is determined as follows: ,in, is the elastic modulus of the glue, obtained from the glue material data sheet, is the recommended dispensing volume, which can be obtained through the dispensing machine program or AOI inspection. H is the height of the glue dot, which can also be obtained through the dispensing machine program or AOI inspection. If the recommended dispensing volume exceeds the upper limit of the dispensing volume, the upper limit of the dispensing volume is used as the compensation parameter of the current qualified glue base, and the PCB package design results of the corresponding components are analyzed again. Otherwise, the position corresponding to the current qualified glue base and the PCB package design results of the components corresponding to the recommended dispensing volume are input into the production process monitoring design library.

[0051] If the recommended dispensing volume exceeds the upper limit of the dispensing volume, the upper limit of the dispensing volume is used as the compensation parameter of the current qualified glue base, and the PCB package design results of the corresponding components are analyzed again, including: According to the compensation parameters of the current qualified glue base, the fixed reaction force provided by the glue point is reversed and substituted into the equation , re-execute S15 and S16 to determine the corresponding component inclination angle under the upper limit of the dispensing volume; If the corresponding component tilt angle does not exceed the maximum reflow soldering warp angle under the upper limit of the dispensing volume, the position corresponding to the current qualified glue base and the recommended dispensing volume will be used as the PCB package design result of the corresponding component and entered into the production process monitoring design library; If the corresponding component inclination angle exceeds the maximum reflow soldering warp angle under the upper limit of the dispensing volume, the adaptive path compensation program is triggered again, the dispensing coordinates are adjusted again, a qualified glue base is obtained, and S21 and S22 are repeated to obtain the PCB package design results of the corresponding components.

[0052] In this embodiment, the present invention automatically performs compensation of the PCB package design results after triggering the warning flag. Specifically, (1) First, the system calculates the recommended glue dispensing volume. The core approach is to make the total torque M = 0, that is, the rotation torque generated by the difference in wetting tension on the left and right pads is completely balanced with the fixing torque provided by the glue, thereby preventing the component from continuing to rotate and tilt. The physical meaning of the total torque M = 0 here is that the eccentric fixing reaction force provided by the glue point offsets the rotation and overturning tendency caused by the uneven pad tension.

[0053] (2) Then, based on the glue point fixed reaction force obtained by balance (such as 0.004N), combined with the glue characteristics and the target compression height (H=0.2mm), the recommended glue volume is calculated (for example, 0.28 ). This allows the glue point to generate just enough fixing torque during reflow soldering.

[0054] (3) If the recommended dispensing volume exceeds the upper limit allowed by the dispensing machine (for example, the maximum is 0.25 ), the upper limit value is used as the compensation parameter of the current qualified glue base, that is, when no more glue can be added, the packaging performance under this condition is analyzed.

[0055] (4) Next, the system resubstitutes the total moment equation based on the upper limit of the adhesive base fixing force and executes S15 and S16 to calculate the component tilt angle under this condition (for example, 0.42°). If it does not exceed the maximum allowable reflow warp angle (0.5°), the dispensing coordinates and volume are used as the final PCB package design results and written into the production process monitoring design library so that it can be directly called for later large-scale packaging.

[0056] (5) If the limit is still exceeded (e.g., 0.55° is calculated), the adaptive path compensation program is triggered again to fine-tune the dispensing coordinates (e.g., adjust the target glue point from X = 20.1 to X = 20.05), obtain a new qualified glue base, and repeat S21 and S22 to form a closed-loop optimization.

[0057] Through the above-mentioned logical closed-loop process, compared with the traditional approach that relies on experience-based adjustment, the present invention can achieve dynamic iteration and precise correction under the influence of multiple factors such as dispensing volume, glue dot offset, and wetting tension coupling, ensuring that each component remains within the maximum warpage angle tolerance after reflow soldering, further improving packaging reliability and batch consistency, and effectively preventing the risks of cold solder joints, short circuits, and assembly interference caused by excessive warpage.

[0058] For example, during the PCB package design process for a large-size LGA device, based on a previously determined offset sensitivity coefficient of γ = 4.0, real-time dispensing testing revealed that the actual dispensing offset distance ΔC of the currently qualified adhesive base was 0.08mm, with a predicted tilt angle of 0.32°, exceeding the maximum allowable reflow soldering warp angle of 0.25° and triggering a warning flag.

[0059] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A PCB packaging design method for SMT electronic components, characterized by: The following steps are included: Determine the package center of gravity of each component in advance, and construct the offset sensitivity coefficient based on the package center of gravity and the target glue point center position. Combined with the maximum reflow soldering warp angle, determine the maximum allowable offset. The maximum allowable offset is used to determine the qualified glue base. During the implementation phase of the dispensing equipment, the qualified glue base is determined based on the maximum allowable deviation; Based on the position corresponding to the qualified adhesive base, the estimated component tilt angle is obtained. The estimated component tilt angle is used to identify the PCB package design results and early warning flags. The PCB package design results are used to summarize the relevant parameters that meet the tilt angle standards. When the warning flag is triggered, an attempt is made to perform compensation work on the PCB package design results.

2. The PCB packaging design method for SMT electronic components according to claim 1, wherein: Obtain the package parameters and position coordinates of each component on the PCB in advance. The package parameters include package length, package width, target glue point center position, and maximum reflow soldering warp angle. Determine the package center of gravity of each component based on the package outline parameters; The offset sensitivity coefficient is constructed by the package center of gravity position and the target glue point center position, and the maximum allowable offset is determined by combining the maximum reflow soldering warp angle.

3. The PCB packaging design method for SMT electronic components according to claim 2, wherein: The offset sensitivity coefficient is constructed by the package center of gravity position and the target glue point center position, and combined with the maximum reflow soldering warp angle, the maximum allowable offset is determined, including: Establish support lines through the contact points of component pins on the pads on both sides; S11: Establish a vector difference between the target glue point center position and the package gravity center position to obtain the designed eccentric distance; S12: During reflow soldering, obtain the wetting tension formed when the solder paste melts on both sides of the pad and the fixed counterforce provided by the glue point; S13: The torque generated by the designed eccentric distance is obtained by multiplying the designed eccentric distance by the fixed reaction force provided by the glue point; S14: Obtain the tension difference between the pads on both sides according to the wetting tension generated when the solder paste melts on both sides of the pad. Multiply the tension difference between the pads on both sides by the vertical distance from the pad to the center of gravity of the package to generate a rotational torque. S15: Obtain the total moment based on the equilibrium condition of plane rigid body statics; S16: Obtain the component inclination angle according to the total torque and package shape parameters; By randomly replacing the center position of the target glue point multiple times, multiple sets of designed eccentric distances are obtained, and the corresponding component inclination angles are obtained through S11 to S16. After numerical differentiation, the offset sensitivity coefficient is obtained; Among them, the offset sensitivity coefficient is used to analyze the incremental impact on the component's post-reflow tilt angle when the glue point offset changes; The maximum allowable offset is determined based on the maximum reflow soldering warp angle and the method for obtaining the offset sensitivity coefficient.

4. The PCB packaging design method for SMT electronic components according to claim 3, characterized in that: During the dispensing equipment implementation phase, the qualified glue base is determined based on the maximum allowable deviation, including: During the implementation phase of the dispensing equipment, the actual dispensing position is monitored in real time, and the actual dispensing offset distance is determined in combination with the target glue point center position; The actual dispensing position is compared with the center position of the target glue point. If the actual dispensing offset distance does not exceed the maximum allowable offset, the actual dispensing position is taken as a qualified glue base. Otherwise, the adaptive path compensation program is triggered to readjust the dispensing coordinates until the actual dispensing offset distance does not exceed the maximum allowable offset. The dispensing coordinates are adjusted and a qualified glue base is obtained.

5. The PCB packaging design method for SMT electronic components according to claim 4, characterized in that: S21: Based on the position corresponding to the qualified glue base, obtain the estimated component tilt angle, including: According to the qualified glue base, determine the corresponding actual dispensing offset distance and mark it as the actual deviation; By obtaining the offset sensitivity coefficient, the offset sensitivity coefficient is multiplied by the actual deviation to obtain the estimated component tilt angle; Identify PCB package design results based on estimated component tilt angles.

6. The PCB packaging design method for SMT electronic components according to claim 5, characterized in that: S22: Based on the estimated component tilt angle, identify the PCB package design results, including: If the estimated component tilt angle exceeds the maximum reflow soldering warp angle, the warning flag is triggered and an attempt is made to compensate for the PCB package design results. If the estimated component tilt angle does not exceed the maximum reflow soldering warp angle, the position and dispensing volume corresponding to the current qualified glue base will be used as the PCB package design results of the corresponding component and entered into the production process monitoring design library.

7. The PCB packaging design method for SMT electronic components according to claim 6, characterized in that: When the warning flag is triggered, an attempt is made to compensate the PCB package design results. include, To calculate the recommended dispensing volume, let the total moment be 0, that is, the equation , where is the wetting tension on the left side of the pad, is the wetting tension on the right side of the pad, is the vertical distance from the pad to the center of gravity of the package, Provides a fixed reaction force for the glue point, is the design eccentric distance; Solving for variables , where the variable Indicates the fixed reaction force provided by the glue point; Determine the recommended dispensing volume based on the fixed reaction force provided by the solved glue point; If the recommended dispensing volume exceeds the upper limit of the dispensing volume, the upper limit of the dispensing volume is used as the compensation parameter of the current qualified glue base, and the PCB package design results of the corresponding components are analyzed again. Otherwise, the position corresponding to the current qualified glue base and the PCB package design results of the components corresponding to the recommended dispensing volume are input into the production process monitoring design library.

8. The PCB packaging design method for SMT electronic components according to claim 7, characterized in that: If the recommended dispensing volume exceeds the upper limit of the dispensing volume, the upper limit of the dispensing volume is used as the compensation parameter of the current qualified glue base, and the PCB package design results of the corresponding components are analyzed again, including: According to the compensation parameters of the current qualified glue base, the fixed reaction force provided by the glue point is reversed and substituted into the equation , re-execute S15 and S16 to determine the corresponding component inclination angle under the upper limit of the dispensing volume; If the corresponding component tilt angle does not exceed the maximum reflow soldering warp angle under the upper limit of the dispensing volume, the position corresponding to the current qualified glue base and the recommended dispensing volume will be used as the PCB package design result of the corresponding component and entered into the production process monitoring design library; If the corresponding component inclination angle exceeds the maximum reflow soldering warp angle under the upper limit of the dispensing volume, the adaptive path compensation program is triggered again, the dispensing coordinates are adjusted again, a qualified glue base is obtained, and S21 and S22 are repeated to obtain the PCB package design results of the corresponding components.

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