A method and system for differential signal interference compensation for LVDS connectors

Abstract

The application discloses a differential signal interference compensation method and system of an LVDS connector and belongs to the technical field of LVDS connectors.The application analyzes the differential sampling waveforms corresponding to each differential channel, extracts differential transmission state data representing the current differential signal transmission state, identifies impedance mismatch interference components and crosstalk interference components caused by adjacent channel coupling changes based on the differential transmission state data, determines the influence degree of each interference component on the current differential signal transmission quality, dynamically adjusts the signal compensation parameters corresponding to the current differential channel according to the influence degree of each interference component, and obtains the differential signal interference compensation result, thereby solving the problem that in the high-resolution image continuous output scene, the differential signal interference compensation is difficult to realize accurate identification and dynamic adjustment on the time-varying distortion state due to the impedance mismatch and channel crosstalk changes of the LVDS connector.

Description

Technical Field

[0001] This invention relates to the field of LVDS connector technology, and in particular to a differential signal interference compensation method and system for LVDS connectors. Background Technology

[0002] LVDS connectors, as crucial interconnect components in low-voltage differential signal transmission links, are widely used in display modules, industrial control equipment, machine vision equipment, automotive electronics, and high-speed data transmission systems. They are primarily used to achieve high-speed differential signal transmission between circuit boards, modules, or cables. LVDS connectors typically include an insulating body, multiple conductive terminals within the insulating body, differential signal terminal pairs for transmitting differential signals, and grounding terminals or shielding structures for suppressing electromagnetic interference. In practical applications, the differential signal output from the transmitting end is usually coupled into the corresponding transmission channel via the LVDS connector and then transmitted to the receiving end for differential resolution.

[0003] Various transmitter structures for implementing LVDS differential signal output have been disclosed in the prior art. For example, the low-voltage differential signal transmitter disclosed in Chinese invention patent application CN102624656B includes: a transmitter including a power supply, a transmitter body, a first selection input module, and a second selection input module. The transmitter body includes a first PMOS transistor, a second PMOS transistor, a first NMOS transistor, and a second NMOS transistor. The source of the first PMOS transistor and the source of the second PMOS transistor are connected to the power supply. Both the first selection input module and the second selection input module are loaded with a first signal, a second signal, a first bias voltage, and a second bias voltage. The first bias voltage or the second bias voltage is selected and input to the gate of the first PMOS transistor and the gate of the second PMOS transistor according to the first signal and the second signal, respectively. The voltage loaded on the gate of the first PMOS transistor and the voltage loaded on the gate of the second PMOS transistor are different in real time. The first signal and the second signal are a pair of differential signals to complete the LVDS transmitter function.

[0004] Because LVDS signals have characteristics such as high transmission rate, low swing, and strong immunity to common-mode interference, high requirements are placed on the electrical performance, impedance continuity, and differential pair consistency of the connector transmission structure. However, in practical applications, the internal terminal structure of LVDS connectors is complex, and the pin distribution is dense. Furthermore, there are problems such as impedance mismatch, parasitic parameter differences, and enhanced electromagnetic coupling between LVDS connectors and the preceding and following stage traces, cables, or interface units. These issues can lead to differential signal reflection, crosstalk, time delay offset, and common-mode noise superposition, affecting signal transmission integrity and receiver identification accuracy. Therefore, effective compensation for differential signal interference in LVDS connectors is of great significance for improving the transmission stability of high-speed differential links, reducing the risk of bit errors, and ensuring the overall reliability of the system. Existing methods usually compensate for differential signal interference based on the following process: First, the transmitting end outputs differential signals through the LVDS driver and transmits them to the receiving end through connectors, cables, or differential traces on printed circuit boards. During transmission, due to factors such as connector impedance discontinuity, inconsistent differential pair lengths, differences in trace distribution parameters, and crosstalk between adjacent channels, differential signals are prone to problems such as amplitude attenuation, edge broadening, timing skew, and common-mode noise superposition. To address this, existing technologies typically first detect or model the differential impedance, insertion loss, internal skew, and crosstalk level of the LVDS channel. Then, based on the analysis results, they compensate and adjust the corresponding circuit parameters at both ends of the connector or in the transmission link, such as termination matching parameters, drive strength parameters, and pre-emphasis parameters. Compensation methods usually include configuring a matching termination resistor at the receiver to suppress reflections, performing length compensation or sampling timing correction based on the differential pair delay deviation, and combining pre-emphasis, equalization, or common-mode rejection to improve the signal eye diagram quality. This reduces the impact of interference on the stability of differential transmission, improves the accuracy of the receiver in identifying the effective differential signal, and enhances the reliability of the link transmission.

[0005] LVDS connectors have a wide range of applications. For example, in industrial vision inspection equipment, LVDS connectors can be used to transmit high-speed image data signals. Image data acquired by industrial cameras usually needs to be transmitted to the image processing main control board via LVDS connectors to complete subsequent image analysis, defect identification, or size measurement. During continuous high-speed transmission, especially in scenarios involving continuous output of high-resolution images, factors such as impedance matching errors between connectors and preceding / following stage traces, as well as increased crosstalk between adjacent channels, may lead to differential signal amplitude attenuation and timing skew. This makes it difficult to accurately identify the source of signal distortion during differential signal interference compensation and to make timely adjustments to compensation parameters. The reasons for this are as follows: Firstly, during continuous output of high-resolution images, the data transmission rate is high and channel switching is frequent, making the originally small impedance discontinuity at the connector more easily amplified, resulting in more obvious reflection and attenuation of the differential signal during transmission. Secondly, when multiple image data are transmitted in parallel, the electromagnetic coupling between adjacent channels is more pronounced, easily causing crosstalk superposition, which in turn makes timing deviations and signal quality fluctuations more dynamic and complex. In addition, interference at the connector is often mixed with the overall link loss, making it difficult to effectively distinguish between local connector problems and overall transmission problems during compensation.

[0006] Existing technologies typically compensate differential signals by terminal matching, pre-emphasis at the transmitting end, equalization at the receiving end, or static compensation based on preset parameters. In scenarios with continuous output of high-resolution images, these technologies usually have the following drawbacks: it is difficult to make real-time adjustments based on impedance fluctuations and crosstalk changes at the connector, the compensation adaptability to local time-varying interference is insufficient, and the compensation lag or insufficient accuracy is prone to occur under multi-channel parallel high-speed transmission conditions.

[0007] For example, in AOI (Automated Optical Inspection) scenarios for solder joints after PCB (Printed Circuit Board) surface mounting, industrial cameras need to continuously acquire high-resolution images of the solder joints at both ends of 0402 package resistors, the pin pads of QFN (Quad Flat No-lead Package) chips, and the fine-pitch pin areas. This image data is then transmitted in real-time to the image processing main control board via an LVDS connector to detect solder joint bridging, insufficient solder, cold solder joints, and pin misalignment. When there is impedance mismatch in one of the LVDS connector differential channels, the corresponding image data is prone to amplitude attenuation and edge delay during transmission. Furthermore, if crosstalk between this channel and adjacent differential channels increases, the local image data recovered at the receiving end will exhibit line synchronization shift and grayscale value jumps. Specifically, this manifests as follows: the solder edge contour, which should appear as a continuous arc, may exhibit local misalignment, edge burrs, grayscale discontinuities, or abrupt changes in brightness in the image. For the narrow insulation gap between adjacent pins of the QFN chip, image distortion phenomena such as local blurring, widening of adhesion, or narrowing of the gap may occur. In such cases, when the image processing control board extracts the solder joint morphology features, it is prone to misjudging grayscale diffusion at the edge of a normal solder joint as a bridging defect, or misjudging a solder joint that is still identifiable with slight solder deficiency as an inconspicuous cold solder joint, thus causing false alarms or missed alarms. Especially under conditions of high-speed pipeline operation and continuous acquisition of multiple frames by the camera, these image anomalies caused by local interference from the LVDS connector may persist in several adjacent frames, further affecting the consistency and reliability of solder joint inspection results for the same batch of PCB circuit boards.

[0008] As can be seen from the above, in high-resolution image continuous output scenarios, there is usually a problem that differential signal interference compensation is difficult to achieve accurate identification and dynamic adjustment of time-varying distortion state due to impedance mismatch of LVDS connector and changes in channel crosstalk. Summary of the Invention

[0009] This invention provides a differential signal interference compensation method and system for LVDS connectors. The technical solution is as follows: On the one hand, a differential signal interference compensation method for LVDS connectors is provided. The method includes: S1, analyzing the differential sampling waveforms corresponding to each differential channel to extract differential transmission state data characterizing the current differential signal transmission state; S2, based on the differential transmission state data, identifying impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels, and determining the degree of influence of each interference component on the current differential signal transmission quality; S3, dynamically adjusting the signal compensation parameters corresponding to the current differential channel according to the degree of influence of each interference component, and obtaining the differential signal interference compensation result.

[0010] On the other hand, a differential signal interference compensation system for an LVDS connector is provided, comprising: a waveform analysis and state extraction module, a differential signal interference component identification module, and a differential signal interference compensation module; wherein, the waveform analysis and state extraction module is used to analyze the differential sampling waveforms corresponding to each differential channel and extract differential transmission state data characterizing the current differential signal transmission state; the differential signal interference component identification module is used to identify impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels based on the differential transmission state data, and determine the degree of influence of each interference component on the current differential signal transmission quality; the differential signal interference compensation module is used to dynamically adjust the signal compensation parameters corresponding to the current differential channel according to the degree of influence of each interference component, and obtain the differential signal interference compensation result.

[0011] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: 1. This invention analyzes the differential sampling waveforms corresponding to each differential channel to extract differential transmission status data characterizing the current differential signal transmission state. This helps improve the accuracy and real-time performance of differential signal transmission status identification, avoids misjudgments of interference due to incomplete transmission status identification, and accurately captures subtle distortion features of the differential signal, providing reliable data support for subsequent interference component identification and compensation parameter adjustment. Based on the differential transmission status data, it identifies impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels, and determines the degree of influence of each interference component on the current differential signal transmission quality. This helps to achieve accurate separation and differentiated identification of the two core interference components, breaking the limitation of traditional technologies that cannot effectively distinguish between local interference and overall link loss. According to the degree of influence of each interference component, it dynamically adjusts the signal compensation parameters corresponding to the current differential channel to obtain differential signal interference compensation results. This helps to ensure the stability and integrity of differential signal transmission in high-resolution image continuous output scenarios, reduce signal amplitude attenuation, timing skew, and other problems, thereby improving the anti-interference capability of the LVDS connector transmission link.

[0012] 2. By acquiring the channel correlation analysis data of the current differential channel and the adjacent channel correlation analysis data of the adjacent differential channels, and based on the channel correlation analysis data, identifying impedance mismatch interference components, and based on the adjacent channel correlation analysis data, identifying crosstalk interference components, compared with the shortcomings of the prior art that easily misjudges crosstalk interference as impedance mismatch interference or link loss, the advantages of this invention are that it can accurately capture the crosstalk interference characteristics caused by the coupling changes of adjacent channels, realize the accurate distinction between impedance mismatch interference and crosstalk interference, and at the same time, it can track the state changes of adjacent channels in real time, predict the enhancement or weakening trend of crosstalk interference in advance, provide forward-looking support for subsequent compensation parameter adjustment, and improve the timeliness and pertinence of compensation.

[0013] 3. This invention obtains the quantified values ​​of the impact of each interference component on the current differential signal transmission quality, and determines the adjustment strategy of the signal compensation parameters based on the magnitude relationship between the quantified values ​​of the impact of impedance mismatch interference components and crosstalk interference components on the current differential signal transmission quality. Compared with the shortcomings of existing technologies, such as easy compensation lag or insufficient compensation accuracy, the advantages of this invention are that it can achieve dynamic adaptation of the compensation strategy with the support of quantified data, avoid blind compensation, ensure that compensation resources are preferentially allocated to interference components with higher impact, and it can iteratively adjust the compensation strategy in real time according to the dynamic changes in the degree of interference impact, which not only ensures the compensation accuracy, but also avoids the increase in circuit power consumption caused by overcompensation.

[0014] 4. When high-resolution multi-channel images are continuously output at full load and strong crosstalk occurs simultaneously in adjacent channels, the current differential channel is determined to be in an extreme composite interference state based on the quantized values ​​of the impact of impedance mismatch interference components on the current differential signal transmission quality and the quantized values ​​of the impact of crosstalk interference components on the current differential signal transmission quality. Compared with the shortcomings of existing technologies, such as the failure of compensation strategies when faced with strong interference superposition and the tendency to cause signal transmission interruption or severe distortion, the advantage of this invention is that it can accurately identify extreme composite interference scenarios and reduce compensation loss of control caused by the superposition of two strong interferences. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A flowchart illustrating a differential signal interference compensation method for an LVDS connector provided in this application embodiment; Figure 2A schematic diagram illustrating the adjustment strategy for determining signal compensation parameters provided in an embodiment of this application; Figure 3 This is a schematic diagram of the differential signal interference compensation system for an LVDS connector provided in an embodiment of this application; Figure 4 This is the original eye diagram of the differential channel of the LVDS connector provided in the embodiments of this application; Figure 5 The original channel impulse response diagram provided in the embodiments of this application; Figure 6 The clock cycle distribution histogram provided for the embodiments of this application. Detailed Implementation

[0017] Embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of the present disclosure are shown in the drawings, it should be understood that embodiments of the present disclosure may be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present disclosure.

[0018] It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure. In the description of the embodiments of this disclosure, the term "comprising" and similar terms should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "this embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects.

[0019] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0020] The first embodiment, as follows Figure 1 The diagram shown is a flowchart of a differential signal interference compensation method for an LVDS connector provided in an embodiment of this application. The method includes the following steps: S1, during the process of transmitting high-resolution image data by carrying differential signals through the LVDS connector, the differential sampling waveforms corresponding to each differential channel are analyzed to extract differential transmission status data that characterizes the current differential signal transmission state. The differential transmission status data includes at least differential signal amplitude data and differential signal timing offset data. For example, in the AOI inspection scenario of solder joints after PCB board surface mounting, by analyzing the sampling waveforms of each differential channel corresponding to the solder joint images at both ends of the 0402 package resistor, the QFN chip pin pad image, and the fine-pitch pin area image, it is helpful to extract the differential signal amplitude attenuation state and timing drift state during the current image transmission process. This helps to detect signal distortion signs in the LVDS connector transmission link in advance before obvious image anomalies occur in the solder joint edge contour, pin gap contour, and grayscale transition area.

[0021] S2, based on differential transmission status data, identifies impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels, and determines the degree of influence of each interference component on the current differential signal transmission quality; for example, by performing correlation analysis on differential signal amplitude data and timing offset data in the corresponding solder joint image transmission channel, and combining the synchronous changes of adjacent channels, it helps to improve the ability to distinguish between independent distortion caused by local impedance discontinuity of LVDS connector and crosstalk distortion caused by enhanced coupling between adjacent differential channels, and thus helps to more accurately determine whether local grayscale abrupt changes, edge blurring or horizontal synchronization offset in the solder joint area image are mainly caused by impedance mismatch or crosstalk interference.

[0022] S3, based on the degree of influence of each interference component, dynamically adjust the signal compensation parameters corresponding to the current differential channel to obtain the differential signal interference compensation result, so as to compensate for the time-varying distortion state during the differential signal transmission process. The signal compensation parameters include terminal matching parameters and drive strength parameters. For example, in the AOI inspection scenario of solder joints after PCB board surface mounting, based on the degree of influence of impedance mismatch interference components and crosstalk interference components on the current differential signal transmission quality, dynamically adjust the terminal matching parameters and drive strength parameters. This helps to achieve targeted compensation for differential signal amplitude attenuation, edge distortion and timing offset during solder joint image transmission, thereby helping to improve the clarity of solder joint edge contours, grayscale distribution stability and image recovery accuracy of fine-pitch pin areas, and reduce the risk of normal solder joints being misjudged as bridging defects or minor cold solder joints being missed.

[0023] In this embodiment, S1, S2, and S3 provided by the present invention are interconnected and do not exist independently, as reflected in the following aspects: S1 is used to extract differential signal amplitude data and differential signal timing offset data from the differential signal transmission process carried by the LVDS connector, providing basic data support for subsequent interference identification; S2, based on the differential transmission status data extracted by S1, distinguishes and identifies impedance mismatch interference components and crosstalk interference components in the current differential channel, and further quantifies the degree of their impact on differential signal transmission quality, providing a basis for subsequent compensation decisions; S3, based on the interference identification results and impact quantification results output by S2, dynamically adjusts the terminal matching parameters and drive strength parameters to form the corresponding differential signal interference compensation results; the three are connected sequentially and progressively, jointly constituting the differential signal interference compensation process for high-resolution image transmission scenarios of LVDS connectors.

[0024] Furthermore, the differential sampling waveforms corresponding to each differential channel are analyzed to extract differential transmission status data representing the current differential signal transmission status. The specific process is as follows: During the transmission of high-resolution image data based on the LVDS connector, the differential sampling waveforms corresponding to each differential channel within the current sampling period are read. The read differential sampling waveforms corresponding to each differential channel are segmented to obtain amplitude extraction segments and timing recognition segments. High-resolution image data represents the continuous output image data corresponding to an image resolution greater than a preset image resolution threshold. Continuous output image data corresponding to an image resolution less than or equal to the preset image resolution threshold is not processed. Continuous output image data represents the timing data continuously output by the industrial camera at a preset sampling frequency during continuous acquisition. Image data streams include continuously output single-frame images, adjacent-frame images, and multi-frame images. The specific acquisition process of amplitude extraction segments and timing recognition segments is as follows: The feature data of the differential sampling waveform corresponding to each differential channel is input into the preset waveform segment recognition model to identify the corresponding amplitude extraction segments and timing recognition segments. The feature data of the differential sampling waveform refers to the input data used to characterize the change characteristics of the differential sampling waveform segments, including at least the differential sampling waveform slope, rising edge slope, and falling edge slope. The amplitude extraction segment represents the target waveform segment in the differential sampling waveform used to extract the amplitude change state of the differential signal, that is, to extract the amplitude data of the differential signal. The timing recognition segment represents the target waveform segment in the differential sampling waveform used to identify the timing offset state of the differential signal, that is, to extract the timing offset data of the differential signal.

[0025] The differential signal interference compensation method for an LVDS connector provided in this application has a database containing various types of data pre-built before implementation to support the processing of differential sampling waveform segment identification, interference component identification, and dynamic adjustment of compensation parameters.

[0026] The database includes, but is not limited to, preset thresholds and preset ranges, such as preset image resolution thresholds, qualified channel correlation analysis numerical ranges, and qualified adjacent channel correlation analysis numerical ranges.

[0027] The following uses a preset image resolution threshold as an example to illustrate the process of obtaining such a preset threshold: First, acquire multiple sets of image acquisition data corresponding to the target industrial vision inspection equipment, such as an industrial camera, during its historical operation. These multiple sets of image acquisition data include at least continuously output image data acquired under different image resolution conditions. Then, group the multiple sets of image acquisition data according to image resolution, and statistically analyze the detection accuracy, false negative rate, and false positive rate of each set of image acquisition data in the corresponding defect identification task or dimensional measurement task. Next, determine the image resolution range that meets the preset detection accuracy requirements, preset edge recognition requirements, and preset dimensional measurement error requirements as candidate resolution ranges, and select the lower limit resolution value from the candidate resolution range as the preset image resolution threshold. For example, in the AOI inspection scenario of solder joints after PCB board surface mounting, multiple sets of continuously output image data formed by the industrial camera during historical inspection can be acquired and divided into multiple resolution levels such as 1600×1200, 2048×1536, 2592×1944, and 3072×2048 according to image resolution; further subdivision... The detection results for solder joint bridging defects at both ends of 0402 package resistors, cold solder joint defects on QFN chip pins, and fine-pitch pin misalignment defects were statistically analyzed at various resolution levels. For example, the detection accuracy rate was 91.2%, the false negative rate was 5.8%, and the false positive rate was 3.0% at 1600×1200 resolution; the detection accuracy rate was 94.6%, the false negative rate was 3.6%, and the false positive rate was 1.8% at 2048×1536 resolution; and the detection accuracy rate was 97.3%, the false negative rate was 1.5%, and the false positive rate was 1.2% at 2592×1944 resolution. The detection accuracy rate for a resolution of 3072×2048 is 97.8%, the false negative rate is 1.3%, and the false positive rate is 0.9%. Furthermore, analysis is conducted by considering the clarity of the solder joint edge contour and the dimensional measurement error. For example, when the image resolution reaches 2592×1944 or higher, the continuity of the solder joint edge meets the preset edge recognition requirements, and the solder joint width measurement error is controlled within ±0.01mm. Therefore, the pixel scale corresponding to 2592×1944 can be used as the lower limit of the candidate resolution range, and further determined as the preset image resolution threshold.

[0028] It should be explained that the preset waveform segment recognition model can be constructed based on machine learning algorithms, such as the Long Short-Term Memory (LSTM) network algorithm. The specific process is as follows: First, acquire the feature data of the differential sampling waveforms of each differential channel corresponding to the historical LVDS connector under different transmission states. The feature data of the differential sampling waveforms includes waveform samples under normal transmission state, impedance mismatch state, and crosstalk enhancement state. Then, segment labeling is performed on each differential sampling waveform sample. The stable waveform segments that characterize the effective amplitude state of the differential signal are labeled as amplitude extraction segments, and the zero-crossing change segments or edge transition segments that characterize the timing change state of the differential signal are labeled as timing recognition segments. Next, each differential sampling waveform sample is preprocessed. The preprocessing includes at least one or more of the following: sampling point normalization, waveform length unification, noise filtering, and time window segmentation, to generate a training sample set. The training sample set includes the feature data of the historical differential sampling waveforms and the preset amplitude extraction segments and timing recognition segments.

[0029] After obtaining the training sample set, each training sample is input into a pre-defined Long Short-Term Memory (LSTM) network for training. The LSM network includes at least an input layer, a temporal feature extraction layer, a memory unit layer, and an output layer. The input layer receives the temporal feature data of the differentially sampled waveform. The memory unit layer learns the temporal variation patterns of the differentially sampled waveform and the correlation between consecutive sampling points. The output layer outputs the segment category corresponding to the current waveform segment. During training, segment labels are extracted based on the labeled amplitude and the temporal identification segment labels, and the parameters are iteratively updated to establish a mapping relationship between the temporal variation features of the differentially sampled waveform and the target segment type within the LSM network.

[0030] After the model training is completed, the recognition accuracy of the trained model is verified using validation samples. When the model's recognition accuracy for amplitude extraction segments and time sequence recognition segments meets the preset recognition requirements, the trained model is determined as the preset waveform segment recognition model.

[0031] In practical applications, the differential sampling waveform feature data corresponding to each differential channel within the current sampling period is input into the preset waveform segment recognition model to identify and output the corresponding amplitude extraction segment and timing recognition segment.

[0032] It should also be mentioned that the embodiments of this invention provide models with similar functions to the preset waveform segment identification model, including a preset differential signal transmission influence model, a preset impedance matching parameter adjustment model, a signal compensation parameter re-output model, a preset crosstalk suppression parameter adjustment model, and a preset impedance crosstalk collaborative adjustment model. All of the above models can be constructed by using existing machine learning algorithms, such as long short-term memory network algorithms, through training, verification and other processes.

[0033] The training samples for the preset differential signal transmission impact model include historical impedance mismatch interference components, crosstalk interference components, differential signal transmission quality parameters, and quantified values ​​of the impact of preset impedance mismatch interference components on the current differential signal transmission quality, as well as quantified values ​​of the impact of crosstalk interference components on the current differential signal transmission quality. The training samples for the preset impedance matching parameter adjustment model include historical impedance mismatch interference components, initial impedance matching parameters, and preset target impedance matching parameters. The training samples for the signal compensation parameter re-output model include historical differential signal transmission quality parameters and preset signal compensation parameters. The training samples for the preset crosstalk suppression parameter adjustment model include historical crosstalk interference components, initial crosstalk suppression parameters, and preset target crosstalk suppression parameters. The training samples for the preset impedance crosstalk collaborative adjustment model include historical impedance mismatch interference components, crosstalk interference components, initial impedance matching parameters, initial crosstalk suppression parameters, and preset target impedance matching parameters and target crosstalk suppression parameters.

[0034] The preset differential signal transmission impact model takes impedance mismatch interference components, crosstalk interference components, and differential signal transmission quality parameters as inputs, and outputs quantified values ​​of the impact of impedance mismatch interference components and crosstalk interference components on the current differential signal transmission quality. The preset impedance matching parameter adjustment model takes impedance mismatch interference components and initial impedance matching parameters as inputs, and outputs target impedance matching parameters. The signal compensation parameter re-output model takes differential signal transmission quality parameters as inputs, and outputs signal compensation parameters. The preset crosstalk suppression parameter adjustment model takes crosstalk interference components and initial crosstalk suppression parameters as inputs, and outputs target crosstalk suppression parameters. The preset impedance crosstalk collaborative adjustment model takes impedance mismatch interference components, crosstalk interference components, initial impedance matching parameters, and initial crosstalk suppression parameters as inputs, and outputs target impedance matching parameters and target crosstalk suppression parameters.

[0035] It also needs further explanation that the slope of the differential sampling waveform represents the degree of amplitude change of the differential sampling waveform monitored by a digital sampling oscilloscope per unit time. Specifically, it can be expressed as the ratio of the difference in differential signal voltage amplitude between two adjacent sampling moments to the corresponding time interval. The rising edge slope represents the degree of amplitude change of the differential sampling waveform monitored by a digital sampling oscilloscope during the transition from a low-level state to a high-level state per unit time. Specifically, it can be expressed as the ratio of the increment of the differential signal voltage amplitude within the rising edge segment to the corresponding time increment. The amplitude increment represents the differential signal voltage amplitude relative to the previous moment or the beginning of the transition. The increment in time and the falling edge slope represent the degree of amplitude change per unit time of the differential sampling waveform monitored by the digital sampling oscilloscope during the transition from a high-level state to a low-level state. Specifically, it can be expressed as the ratio of the decrease in the amplitude of the differential signal voltage in the falling edge segment to the corresponding time increment. The amplitude decrease represents the amount by which the differential signal voltage amplitude decreases relative to the previous or starting time. The rising edge segment represents the waveform segment in the differential sampling waveform where the amplitude continuously increases and the corresponding signal state switches from low to high. The falling edge segment represents the waveform segment in the differential sampling waveform where the amplitude continuously decreases and the corresponding signal state switches from high to low.

[0036] Within the amplitude extraction section, the amplitude change representing the current differential signal amplitude change state is extracted as differential signal amplitude data. Specifically, the amplitude change is the absolute value of the difference between the peak-to-peak value of the current differential sampling waveform monitored by a high-speed oscilloscope and a differential probe and the reference peak-to-peak value of a preset reference differential waveform. Within the timing identification section, the timing offset representing the state of the current differential signal changing ahead or behind the reference sampling time is extracted as differential signal timing offset data. Specifically, the timing offset is the absolute value of the time difference between the zero-crossing point of the current differential sampling waveform monitored by a timer and the zero-crossing point of the preset reference waveform.

[0037] In this embodiment, by analyzing the differential sampling waveforms corresponding to each differential channel and extracting differential signal amplitude data and differential signal timing offset data in the amplitude extraction section and timing identification section respectively, it helps to enhance the ability to separate and perceive amplitude and timing changes during the differential signal transmission of the LVDS connector. Compared with the shortcomings of existing technologies that mostly use overall waveform coarse detection, static parameter estimation or single quality index judgment, which are difficult to simultaneously take into account amplitude distortion and timing drift, and are not precise enough in identifying local time-varying anomalies, this helps to more accurately locate the specific manifestation of differential signal distortion and to provide a basis for subsequent impedance mismatch interference components and crosstalk interference. The differentiation and identification of components provides more granular data support. For example, in the scenario of AOI inspection of solder joints after PCB board surface mounting, by extracting the amplitude data of the solder joint image and transmitting the corresponding differential signal amplitude in the amplitude extraction section, and extracting the differential signal timing offset data at the zero-crossing point in the timing identification section, the amplitude attenuation phenomenon caused by the local impedance discontinuity of the LVDS connector can be detected in advance before the edge contour of the solder joint becomes obviously blurred, or the timing drift phenomenon caused by the enhanced coupling of adjacent differential channels can be detected. This helps to reduce the risk of normal solder joints being misjudged as bridging defects, minor cold solder joints being missed, or inaccurate measurement of fine-pitch pin area dimensions.

[0038] Furthermore, based on the differential transmission status data, impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels are identified. The specific process is as follows: The differential signal amplitude data and differential signal timing offset data of the current differential channel are used as channel correlation analysis data; the differential signal amplitude data and differential signal timing offset data corresponding to the current differential channel and adjacent differential channels are used as adjacent channel correlation analysis data; based on the channel correlation analysis data, impedance mismatch interference components are identified: when all channel correlation analysis data are within the corresponding pre-set qualified channel correlation analysis value range, a differential transmission qualified prompt is sent; otherwise, the corresponding channel correlation analysis data is considered as impedance mismatch interference components; crosstalk interference components are identified based on adjacent channel correlation analysis data: when all adjacent channel correlation analysis data are within the corresponding qualified adjacent channel correlation analysis value range, a differential transmission qualified prompt is sent; otherwise, the corresponding adjacent channel correlation analysis data is considered as crosstalk interference components.

[0039] The following example, using the numerical range of qualified channel correlation analysis, illustrates the process of obtaining such preset intervals or ranges: First, acquire channel correlation analysis data for multiple differential channels corresponding to the LVDS connector under historical normal transmission conditions. Perform statistical analysis on multiple sets of channel correlation analysis data generated under historical normal transmission conditions to extract the amplitude variation distribution interval and timing offset distribution interval corresponding to each differential channel under normal transmission conditions. Next, remove abnormal discrete data caused by occasional noise, sampling jitter, or non-connector factors. Based on the remaining channel correlation analysis data, determine the target numerical range that can characterize the qualified state of differential transmission. The target numerical range can be jointly determined by the mean range, fluctuation upper limit range, and timing offset allowable range of the channel correlation analysis data. For example, the differential signal amplitude data and differential signal timing offset data corresponding to multiple differential channels under historical normal transmission conditions can be statistically analyzed separately to form... Multiple sets of channel correlation analysis data were analyzed. Statistical analysis revealed that, under normal transmission conditions, the amplitude variation of the differential signal corresponding to each differential channel was mainly distributed between 0.015V and 0.042V, with an average of 0.028V and an upper limit of fluctuation of 0.050V. The timing offset of each differential channel was mainly distributed between 8ps and 26ps, with an average of 17ps and an allowable upper limit of 30ps. After removing abnormal discrete data caused by occasional noise, sampling jitter, or unstable test probe contact, the data range with amplitude variation between 0.015V and 0.050V and timing offset between 8ps and 30ps was determined as the target numerical range that could characterize the qualified state of differential transmission. Finally, the channel correlation analysis data range that met the preset transmission stability requirements, preset eye diagram quality requirements, and preset error control requirements was determined as the qualified channel correlation analysis numerical range.

[0040] To determine the impact of each interference component on the current differential signal transmission quality, specifically, based on the effects of impedance mismatch interference and crosstalk interference on the differential signal transmission quality parameters, a quantitative value of the impact of each interference component on the current differential signal transmission quality is obtained. The differential signal transmission quality parameters represent a set of data characterizing the high-low level transition during high-speed transmission of differential signals in LVDS connectors, including at least the differential signal rising edge duration and the differential signal falling edge duration. It should be explained that the differential signal rising edge duration represents the time length corresponding to the transition from a preset low level to a preset high level in the differential sampling waveform monitored by the timer, and the differential signal falling edge duration represents the time length corresponding to the transition from a preset high level to a preset low level in the differential sampling waveform monitored by the timer.

[0041] The specific process for obtaining the quantitative values ​​of the impact of each interference component on the current differential signal transmission quality is as follows: Monitor whether the differential signal transmission quality parameters are within the corresponding pre-set acceptable range. The acceptable range includes a preset falling edge duration range and a preset rising edge duration range. If so, send a differential signal transmission acceptable prompt; otherwise, use the impedance mismatch interference component, crosstalk interference component, and differential signal transmission quality parameters as input values ​​to a preset differential signal transmission influence model. Through the preset differential signal transmission influence model, quantitatively evaluate the impact of the impedance mismatch interference component and crosstalk interference component on the current differential signal transmission quality, and output corresponding quantitative values ​​characterizing the strength and weight of the impact of the impedance mismatch interference component and crosstalk interference component on the current differential signal transmission quality. These include the quantitative values ​​of the impact of the impedance mismatch interference component and the crosstalk interference component on the current differential signal transmission quality.

[0042] In this embodiment, channel correlation analysis data is obtained based on the current differential channel, and adjacent channel correlation analysis data is obtained based on adjacent differential channels. Then, based on the channel correlation analysis data and the adjacent channel correlation analysis data, the corresponding impedance mismatch interference components and crosstalk interference components are determined respectively. This helps to improve the ability to distinguish and identify the independent distortion changes of the current differential channel itself and the coupled and linked distortion changes of adjacent channels, thereby enhancing the ability to directionally identify different interference sources during the differential signal transmission of the LVDS connector.

[0043] Based on the effects of impedance mismatch interference and crosstalk interference on differential signal transmission quality parameters, this method obtains quantitative values ​​of the impact of each interference component on the current differential signal transmission quality. Compared to existing technologies that rely on empirical judgments based on single anomalies and struggle to quantify the strength of different interference sources, this method helps to more accurately determine the dominant interference type and its actual impact on differential signal transmission quality. This is more conducive to ensuring the pertinence, rationality, and stability of subsequent signal compensation parameter adjustment strategies.

[0044] like Figure 2The diagram illustrates the adjustment strategy for determining signal compensation parameters provided in an embodiment of this invention: When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is greater than the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, an adjustment method is triggered that first performs impedance mismatch optimization, and then dynamically adjusts the signal compensation parameters; when the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is less than the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, an adjustment method is triggered that first performs crosstalk interference optimization, and then dynamically adjusts the signal compensation parameters; when the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is equal to the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, an adjustment method of coordinated adjustment of signal compensation parameters is triggered.

[0045] Furthermore, based on the degree of influence of each interference component, the signal compensation parameters corresponding to the current differential channel are dynamically adjusted to obtain the differential signal interference compensation result, as follows: The adjustment strategy for the signal compensation parameters is determined based on the quantitative relationship between the impact values ​​of impedance mismatch interference components and crosstalk interference components on the current differential signal transmission quality. The specific process is as follows: When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is greater than the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, the following adjustment method should be triggered, and differential signal interference detection should be performed after the trigger ends: the adjustment method of first performing impedance mismatch optimization and then performing dynamic adjustment of signal compensation parameters should be triggered, that is, the impedance mismatch optimization is set as high priority and the dynamic adjustment of signal compensation parameters is set as low priority, so as to give priority to reducing the amplitude attenuation and timing deviation caused by connector impedance discontinuity or termination mismatch.

[0046] The method of triggering impedance mismatch optimization first, followed by dynamic adjustment of signal compensation parameters, specifically means: Based on the impedance mismatch interference component, the impedance matching parameters related to impedance continuity restoration are adjusted first. After the impedance matching parameters are adjusted, the signal compensation parameters are dynamically adjusted. Specifically, the impedance matching parameter adjustment involves inputting the impedance mismatch interference component and the initial impedance matching parameters into a preset impedance matching parameter adjustment model, and outputting the corresponding target impedance matching parameters. These impedance matching parameters include configurable matching parameters related to the differential signal terminal pairs of the LVDS connector and their preceding and following stage connections when using a configurable matching network. Specifically, these include differential termination configuration parameters, connector input matching configuration parameters, and connector output matching configuration parameters. One or more of the parameters, namely differential termination configuration parameters, connector input matching configuration parameters, and connector output matching configuration parameters, can correspond to different resistor branch selection states, different matching network access states, or different equivalent impedance settings. Among them, the differential termination configuration parameter represents the resistor value set at the LVDS differential signal receiver end for terminating and matching a pair of differential signal transmission paths; the connector input matching configuration parameter represents the resistor value set at the LVDS connector input side for impedance matching the differential signal transmission path before entering the connector; and the connector output matching configuration parameter represents the resistor value set at the LVDS connector output side for impedance matching the differential signal transmission path after leaving the connector.

[0047] By inputting impedance mismatch interference components and initial impedance matching parameters into a preset impedance matching parameter adjustment model to output target impedance matching parameters, the adjustment of parameters such as differential termination configuration parameters, connector input matching configuration parameters, and connector output matching configuration parameters can better match the actual impedance state of the current LVDS connector differential transmission path. This helps to restore the impedance continuity of the differential transmission path, improve the matching degree of LVDS differential signals when transmitted between the connector input side, connector body, and connector output side, and thus reduce signal reflection, waveform distortion, and amplitude contraction caused by termination mismatch or local impedance abrupt changes in the connector.

[0048] When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is less than the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, the following adjustment method should be triggered, and differential signal interference detection should be performed after the trigger ends: trigger the adjustment method of first performing crosstalk interference optimization and then dynamically adjusting the signal compensation parameters, that is, setting crosstalk interference optimization as high priority and dynamic adjustment of signal compensation parameters as low priority, so as to suppress signal fluctuations and coupling distortion caused by the enhancement of crosstalk between adjacent channels.

[0049] The adjustment method, which first optimizes crosstalk interference and then dynamically adjusts signal compensation parameters, has the following specific process: Based on the crosstalk interference components, priority is given to adjusting crosstalk suppression parameters related to crosstalk suppression. Specifically, the crosstalk interference components and initial crosstalk suppression parameters are used as inputs to a preset crosstalk suppression parameter adjustment model. After adjusting the crosstalk suppression parameters to the target crosstalk suppression parameters output by the preset crosstalk suppression parameter adjustment model, the signal compensation parameters are dynamically adjusted. The crosstalk suppression parameters include adjustable parameters related to coupling suppression between adjacent differential signal terminal pairs of the LVDS connector, specifically including one or more of the transmitter pre-emphasis level and transmitter pre-emphasis duration.

[0050] By inputting crosstalk interference components and initial crosstalk suppression parameters into a preset crosstalk suppression parameter adjustment model to output target crosstalk suppression parameters, the settings of crosstalk suppression-related parameters such as the transmitter pre-emphasis level and transmitter pre-emphasis duration can better match the coupling changes between adjacent differential signal terminal pairs. This helps to enhance the ability to suppress crosstalk between adjacent channels, reduce synchronization fluctuations and signal distortion caused by enhanced coupling under multi-channel parallel high-speed transmission conditions, and thus improve the channel isolation effect and signal stability of LVDS connectors in high-resolution image data continuous transmission scenarios.

[0051] When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is equal to the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, the following adjustment method should be triggered, and differential signal interference detection should be performed after the trigger ends: the adjustment method of coordinated adjustment of the trigger signal compensation parameters.

[0052] The specific process of the coordinated adjustment of the trigger signal compensation parameters is as follows: Based on the impedance mismatch interference component and the crosstalk interference component, the impedance matching parameter and the crosstalk suppression parameter are adjusted simultaneously. That is, based on the impedance mismatch interference component, the crosstalk interference component, the initial impedance matching parameter and the initial crosstalk suppression parameter as the input of the preset impedance crosstalk coordinated adjustment model, the crosstalk suppression parameter and the impedance matching parameter are adjusted to the target impedance matching parameter and the target crosstalk suppression parameter output by the preset impedance crosstalk coordinated adjustment model, and then the signal compensation parameters are dynamically adjusted.

[0053] It should also be noted that the dynamic adjustment of signal compensation parameters means that the differential signal transmission quality parameters are used as inputs to the signal compensation parameter re-output model, and the output signal compensation parameters are used as the new differential signal interference compensation result. Based on the differential signal interference compensation result, the corresponding parameters are set. That is, the termination matching parameters and drive strength parameters corresponding to the current differential channel are updated based on the output signal compensation parameters. The termination matching parameters include adjustable parameters related to the LVDS differential transmission path termination network, specifically one or more of the common-mode termination bias resistor value and the termination network matching resistor ratio. The drive strength parameters specifically include one or more of the LVDS transmitter output current intensity, differential signal voltage swing, PMOS transistor gate bias voltage, and NMOS transistor gate bias voltage. Specifically, PMOS (P-channel Metal-Oxide-Semiconductor Field-Effect Transistor) and NMOS (N-channel Metal-Oxide-Semiconductor Field-Effect Transistor) are used. Field-Effect Transistors (N-channel metal-oxide-semiconductor field-effect transistors) are used to adjust the conduction level of the corresponding transistors in the differential drive circuit of the LVDS transmitter.

[0054] By adjusting impedance matching parameters, crosstalk suppression parameters, or co-adjusting parameters, and then inputting the differential signal transmission quality parameters into the signal compensation parameter re-output model to output new signal compensation parameters and update the terminal matching parameters and drive strength parameters, it is possible to adaptively correct parameters such as the common-mode terminal bias resistor value, the proportion of the termination network matching resistor, the output current intensity of the LVDS transmitter, the differential signal voltage swing, the PMOS transistor gate bias voltage, and the NMOS transistor gate bias voltage on the basis of the aforementioned dominant interference optimization. This not only helps to improve the common-mode stability and differential decision conditions of the receiver termination network, but also helps to adjust the conduction degree of the corresponding transistors in the differential drive circuit of the LVDS transmitter, thereby optimizing the differential signal drive capability, output swing, and edge flipping characteristics, and improving the precision of differential signal transmission quality recovery.

[0055] The differential driving circuit provided in this application is a driving circuit structure for outputting low-voltage differential signals to an LVDS connector and its corresponding differential transmission path. It outputs a preset driving current and controls the voltage swing between a pair of differential signals, so that the differential signals are stably transmitted through the transmission and termination network composed of the connector input end, connector output end, differential end and common-mode termination path, thereby realizing impedance matching, common-mode level control and effective output of differential signals in the differential transmission path. The differential driving circuit includes a positive output end and a negative output end. The positive output end is electrically connected to the positive differential signal terminal corresponding to the LVDS connector, and the negative output end is electrically connected to the negative differential signal terminal corresponding to the LVDS connector. The differential signal terminal pairs of the LVDS connector are electrically connected to the receiving end through the corresponding transmission channel.

[0056] Among them, the common-mode termination bias resistor value represents the resistance value set in the common-mode bias path of the differential signal; the terminating network matching resistor ratio represents the resistance ratio between each matching resistor in the terminating network; the LVDS transmitter output current intensity represents the magnitude of the drive current output by the LVDS transmitter drive circuit to the differential signal transmission channel; and the differential signal voltage swing represents the amplitude of the voltage difference change between a pair of LVDS differential signals, which can be specifically expressed as the instantaneous voltage difference between the differential positive signal and the differential negative signal.

[0057] After the execution trigger ends, differential signal interference detection is performed. During the next preset detection time period, the differential signal transmission quality parameters are monitored to see if they are within the corresponding differential signal transmission quality qualified range. If they are, a differential transmission qualified prompt is sent; otherwise, a differential signal interference compensation warning is sent.

[0058] like Figure 3The diagram shows a schematic of a differential signal interference compensation system for an LVDS connector according to an embodiment of this invention. The system includes: a waveform analysis and state extraction module, a differential signal interference component identification module, and a differential signal interference compensation module. The waveform analysis and state extraction module is used to analyze the differential sampling waveforms corresponding to each differential channel during high-resolution image data transmission carrying differential signals via the LVDS connector, extracting differential transmission state data characterizing the current differential signal transmission state. The differential transmission state data includes at least differential signal amplitude data and differential signal timing offset data. The differential signal interference component identification module is used to identify impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels based on the differential transmission state data, and determine the degree of influence of each interference component on the current differential signal transmission quality. The differential signal interference compensation module is used to dynamically adjust the signal compensation parameters corresponding to the current differential channel according to the degree of influence of each interference component, obtaining differential signal interference compensation results to compensate for time-varying distortion during differential signal transmission. The signal compensation parameters include terminal matching parameters and drive strength parameters.

[0059] In this embodiment, by comparing the quantitative values ​​of the impact of impedance mismatch interference and crosstalk interference on the current differential signal transmission quality, and determining different compensation adjustment strategies accordingly, the differential signal interference compensation process no longer employs a single fixed compensation method, but rather performs differentiated processing based on the dominant interference source. When impedance mismatch interference is dominant, impedance mismatch optimization is prioritized, which can more effectively improve the impedance discontinuity problem in the differential signal terminal pairs of the LVDS connector and their preceding and following stage connection structures, thereby helping to reduce differential signal reflection, reduce amplitude attenuation, and alleviate timing deviations. When crosstalk interference is dominant, crosstalk optimization is prioritized, which can more effectively suppress the enhanced coupling phenomenon between adjacent differential signal terminal pairs, thereby helping to reduce signal fluctuations and coupling distortion. When the influence of the two types of interference components is equal, by simultaneously adjusting the impedance matching parameters and crosstalk suppression parameters, coordinated compensation for the differential signal distortion state under combined interference scenarios can be achieved. This helps to improve the compensation adaptability and accuracy for different interference sources.

[0060] In practical applications, especially in the scenario of solder joint AOI inspection after PCB board surface mounting, the above method helps to improve the amplitude stability, timing consistency and channel anti-crosstalk capability when LVDS connector transmits high-resolution solder joint image data. This helps to improve the recovery accuracy of solder joint edge contour, grayscale transition area and fine-pitch pin area images, and reduce the risk of bridging misjudgment, missed cold solder joints or dimensional measurement deviation caused by local image blurring, grayscale abrupt change or line synchronization offset.

[0061] In the second embodiment, based on the method of the first embodiment, when high-resolution multi-channel images are continuously output at full load and strong crosstalk occurs simultaneously in adjacent channels, the differential signal corresponding to the current differential channel experiences rapid amplitude attenuation during transmission. This reduces the stability of the receiver's effective decision based on the voltage difference between the two differential signals. In this case, the signal compensation parameters corresponding to the current differential channel are dynamically adjusted according to the degree of influence of each interference component to obtain the differential signal interference compensation result. The embodiment also includes: determining whether the current differential channel is in an extreme state based on the quantized values ​​of the influence of impedance mismatch interference components and crosstalk interference components on the current differential signal transmission quality. The differential channel is classified into two states: 1) Impedance mismatch interference and 2) Crosstalk interference. When both the quantized values ​​of their respective impacts on the current differential signal transmission quality are greater than the corresponding pre-set high-risk thresholds, the current differential channel is determined to be in an extreme mixed interference state, and an LVDS connector transmission warning is sent. Conversely, if the values ​​are greater than the pre-set high-risk thresholds, the current differential channel is determined not to be in an extreme mixed interference state. The signal compensation parameter adjustment strategy is determined based on the relationship between the quantized values ​​of the impacts of impedance mismatch interference and crosstalk interference on the current differential signal transmission quality. The pre-set high-risk thresholds include both the high-risk threshold for impedance mismatch interference and the high-risk threshold for crosstalk interference.

[0062] In this embodiment, since the LVDS connector transmits low-swing differential signals, compared to ordinary single-ended signals, its transmission quality depends not only on the amplitude stability of a single path, but also on the amplitude symmetry, timing synchronization, and stability of the differential decision window between the two signals in the differential pair. Therefore, this embodiment does not compensate solely based on the degree of distortion of a single waveform, but further introduces differential symmetry offset data, and constrains and controls the balance restoration of the two branches of the differential signal in extreme scenarios where impedance mismatch interference and crosstalk interference components are simultaneously enhanced, thus better conforming to the actual transmission characteristics of LVDS differential signals. Compared to conventional compensation methods based on static parameters in the prior art, this embodiment can dynamically and collaboratively adjust the compensation strategy to address the low-swing characteristics of LVDS differential signals when high-resolution multi-channel images are continuously output at full load and strong crosstalk occurs simultaneously in adjacent channels, thereby improving the adaptability of the compensation strategy to extreme time-varying distortion states.

[0063] like Figure 4 The figure shows the original eye diagram of the differential channel of the LVDS connector provided in an embodiment of this invention. The horizontal axis represents time, and the vertical axis represents signal level. As can be seen from the figure, without interference compensation, the differential signal is affected by factors such as channel loss, reflection, and inter-symbol interference during transmission. The eye diagram is severely closed, and the decision region is unclear, indicating poor signal integrity and difficulty in achieving reliable decision-making.

[0064] like Figure 5 As shown, this is the original channel impulse response diagram provided in an embodiment of the present invention. The horizontal axis represents time, and the vertical axis represents the normalized impulse response amplitude after normalization. The main peak in the diagram reflects the arrival location of the main energy of the differential signal, and the tail portion after the main peak reflects the influence of factors such as channel loss, impedance discontinuity, reflection, and inter-symbol interference on the signal transmission process.

[0065] like Figure 6 As shown, this is a clock cycle distribution histogram provided in an embodiment of the present invention. The horizontal axis represents the clock cycle, and the vertical axis represents the number of occurrences. The multi-peak distribution in the figure indicates the presence of jitter components caused by channel interference, noise, etc.

[0066] Through the above description of the implementation methods, those skilled in the art can clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the above functions can be divided into different functional modules to complete all or part of the functions described above.

[0067] In the embodiments provided in this application, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A differential signal interference compensation method for an LVDS connector, characterized in that, Includes the following steps: S1, analyze the differential sampling waveforms corresponding to each differential channel, and extract differential transmission state data that characterizes the current differential signal transmission state; S2, based on the differential transmission status data, identify the impedance mismatch interference component and the crosstalk interference component caused by the coupling change of adjacent channels, and determine the degree of influence of each interference component on the current differential signal transmission quality. S3. Based on the degree of influence of each interference component, dynamically adjust the signal compensation parameters corresponding to the current differential channel to obtain the differential signal interference compensation result.

2. The differential signal interference compensation method for an LVDS connector as described in claim 1, characterized in that, The specific process of analyzing the differential sampling waveforms corresponding to each differential channel and extracting differential transmission state data representing the current differential signal transmission state is as follows: During the transmission of high-resolution image data based on the LVDS connector, the differential sampling waveforms corresponding to each differential channel within the current sampling period are read, and the differential sampling waveforms corresponding to each differential channel are segmented to obtain the amplitude extraction segment and the timing recognition segment. The high-resolution image data represents the continuous output image data corresponding to an image resolution greater than a preset image resolution threshold. The continuously output image data refers to the time-series image data stream continuously output by the industrial camera in continuous acquisition mode according to a preset sampling frequency; The specific acquisition process of the amplitude extraction segment and the time sequence identification segment is as follows: The feature data of the differential sampling waveform corresponding to each differential channel are input into the preset waveform segment recognition model to identify the corresponding amplitude extraction segment and timing recognition segment; Within the amplitude extraction section, the amplitude change that characterizes the current amplitude change state of the differential signal is extracted as the differential signal amplitude data; Within the timing identification segment, the timing offset that represents the state of the current differential signal changing ahead or behind the reference sampling time is extracted as the timing offset data of the differential signal.

3. The differential signal interference compensation method for an LVDS connector as described in claim 2, characterized in that, The process of identifying impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels based on the differential transmission state data is as follows: The differential signal amplitude data and differential signal timing offset data of the current differential channel are used as channel correlation analysis data; The differential signal amplitude data and differential signal timing offset data corresponding to the differential channels adjacent to the current differential channel are used as the adjacent channel correlation analysis data; Based on channel correlation analysis data, impedance mismatch interference components are identified: when all channel correlation analysis data are within the corresponding qualified channel correlation analysis value range, a differential transmission qualified prompt is sent; otherwise, the corresponding channel correlation analysis data is regarded as impedance mismatch interference components. Identify crosstalk interference components based on adjacent channel correlation analysis data: When the adjacent channel correlation analysis data are all within the corresponding qualified adjacent channel correlation analysis value range, send a differential transmission qualified prompt; otherwise, treat the corresponding adjacent channel correlation analysis data as crosstalk interference components.

4. The differential signal interference compensation method for an LVDS connector as described in claim 3, characterized in that, Specifically, determining the degree of influence of each interference component on the current differential signal transmission quality means obtaining a quantitative value of the degree of influence of each interference component on the current differential signal transmission quality based on the effect of impedance mismatch interference component and crosstalk interference component on the differential signal transmission quality parameters. The differential signal transmission quality parameters represent a set of data characterizing the high-low level transition during high-speed differential signal transmission of the LVDS connector.

5. The differential signal interference compensation method for an LVDS connector as described in claim 4, characterized in that, The specific process for obtaining the quantification value of the influence of each interference component on the current differential signal transmission quality is as follows: Monitor whether the differential signal transmission quality parameters are within the corresponding acceptable range. If so, send a differential signal transmission acceptable prompt. Otherwise, use impedance mismatch interference components, crosstalk interference components, and differential signal transmission quality parameters as input values ​​for a preset differential signal transmission influence model, and output the corresponding quantized value through the preset differential signal transmission influence model.

6. The differential signal interference compensation method for an LVDS connector as described in claim 1, characterized in that, The signal compensation parameters corresponding to the current differential channel are dynamically adjusted according to the influence degree of each interference component to obtain the differential signal interference compensation result, as detailed below: Based on the quantitative relationship between the impact values ​​of impedance mismatch interference and crosstalk interference on the current differential signal transmission quality, the adjustment strategy for signal compensation parameters is determined. The specific process is as follows: When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is greater than the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, the following adjustment method should be triggered, and differential signal interference detection should be performed after the trigger ends: The triggering method first optimizes impedance mismatch, and then dynamically adjusts signal compensation parameters. When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is less than the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, the following adjustment method should be triggered, and differential signal interference detection should be performed after the trigger ends: The triggering method first optimizes crosstalk interference, and then dynamically adjusts the signal compensation parameters; When the quantized value of the impact of the output impedance mismatch interference component on the current differential signal transmission quality is equal to the quantized value of the impact of the crosstalk interference component on the current differential signal transmission quality, the following adjustment method should be triggered, and differential signal interference detection should be performed after the trigger ends: The adjustment method for coordinated adjustment of trigger signal compensation parameters; The differential signal interference detection after the execution trigger ends monitors whether the differential signal transmission quality parameters are within the corresponding differential signal transmission quality qualified range during the next preset detection time period. If so, a differential transmission qualified prompt is sent; otherwise, a differential signal interference compensation warning is sent.

7. The differential signal interference compensation method for an LVDS connector as described in claim 6, characterized in that, The triggering method of first optimizing impedance mismatch and then dynamically adjusting signal compensation parameters specifically means: based on the impedance mismatch interference components, priority is given to adjusting the impedance matching parameters related to impedance continuity restoration; after the impedance matching parameters are adjusted, the signal compensation parameters are dynamically adjusted. The adjustment of the impedance matching parameters specifically means that the impedance mismatch interference components and the initial impedance matching parameters are input into the preset impedance matching parameter adjustment model, and the corresponding target impedance matching parameters are output. The impedance matching parameters include adjustable parameters related to the differential signal terminal pairs of the LVDS connector and their front and rear stage connection structures. The dynamic adjustment of the signal compensation parameters means that the differential signal transmission quality parameters are used as input to the signal compensation parameter re-output model, and the output signal compensation parameters are used as the new differential signal interference compensation result. Based on the differential signal interference compensation result, the corresponding parameters are set.

8. The differential signal interference compensation method for an LVDS connector as described in claim 6, characterized in that, The triggering method first optimizes crosstalk interference and then dynamically adjusts signal compensation parameters. The specific process is as follows: Based on the crosstalk interference component, the crosstalk suppression parameters related to crosstalk suppression are adjusted first. After the crosstalk suppression parameters are adjusted to the target crosstalk suppression parameters output by the preset crosstalk suppression parameter adjustment model, the signal compensation parameters are dynamically adjusted. The crosstalk suppression parameters include adjustable parameters related to the suppression of coupling between adjacent differential signal terminal pairs of the LVDS connector; The specific process for adjusting the trigger signal compensation parameters collaboratively is as follows: Based on impedance mismatch interference and crosstalk interference, the impedance matching parameters and crosstalk suppression parameters are adjusted simultaneously. After the crosstalk suppression parameters and impedance matching parameters are adjusted to the target impedance matching parameters and target crosstalk suppression parameters output by the preset impedance crosstalk collaborative adjustment model, the signal compensation parameters are dynamically adjusted.

9. The differential signal interference compensation method for an LVDS connector as described in claim 1, characterized in that, The step of dynamically adjusting the signal compensation parameters corresponding to the current differential channel based on the influence degree of each interference component to obtain the differential signal interference compensation result also includes: Based on the quantized values ​​of the impact of impedance mismatch interference on the current differential signal transmission quality and the quantized values ​​of the impact of crosstalk interference on the current differential signal transmission quality, determine whether the current differential channel is in an extreme combined interference state. When the quantized values ​​of the impact of impedance mismatch interference on the current differential signal transmission quality and the quantized values ​​of the impact of crosstalk interference on the current differential signal transmission quality are both greater than the corresponding preset high-risk threshold, an LVDS connector transmission warning is sent. Otherwise, the signal compensation parameter adjustment strategy is determined based on the relationship between the quantized values ​​of the impact of impedance mismatch interference and crosstalk interference on the current differential signal transmission quality.

10. A differential signal interference compensation system for an LVDS connector, characterized in that, include: Waveform analysis and state extraction module, differential signal interference component identification module, and differential signal interference compensation module; The waveform analysis and state extraction module is used to analyze the differential sampling waveforms corresponding to each differential channel and extract differential transmission state data that characterizes the current differential signal transmission state. The differential signal interference component identification module is used to identify impedance mismatch interference components and crosstalk interference components caused by changes in coupling between adjacent channels based on the differential transmission status data, and to determine the degree of influence of each interference component on the current differential signal transmission quality. The differential signal interference compensation module is used to dynamically adjust the signal compensation parameters corresponding to the current differential channel according to the influence degree of each interference component, and obtain the differential signal interference compensation result.

Images