Short circuit protection circuit, array substrate, display device and short circuit protection method

Abstract

The invention relates to the field of display, and discloses a short-circuit protection circuit, an array substrate, a display device and a short-circuit protection method.The short-circuit protection circuit is used for an OLED device and comprises the steps that an information sensing module obtains the actual working current of the OLED device and real-time parameters related to the working state of the OLED device; the dynamic expectation calculation module calculates the dynamic expectation working current n of the OLED device according to the real-time parameters and a preset OLED electrical characteristic model; the decision module synthesizes the actual current, the expected current and the current change rate / fluctuation amplitude to generate a risk judgment signal; and the response control module executes protection operation according to the judgment signal. According to the OLED short-circuit protection method, the accuracy, the sensitivity and the intelligent management level of OLED short-circuit protection are remarkably improved through the technology of dynamically calculating the expected current and carrying out decision making and parameter self-adaptive adjustment by fusing the actual current time sequence characteristics.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a short-circuit protection circuit, an array substrate, a display device and a short-circuit protection method. BACKGROUND

[0002] At present, the organic light emitting diode (OLED) display technology has become one of the mainstream technologies in the modern display field due to its excellent display effect and form advantage. However, the internal organic material or electrode structure of the OLED device may be induced to short-circuit failure due to various factors during the complex manufacturing process and long-term use. Once such short-circuit occurs, it is often accompanied by a sharp increase in local current, which may not only rapidly damage the faulty pixel and form a permanent display defect, reducing the user's observation, but also may impact the driving circuit, and even affect the stable operation and service life of the entire display panel. Therefore, in order to fully exert the advantages of OLED technology and ensure the reliability of its commercial application, it is particularly crucial and urgent to develop an efficient and accurate short-circuit protection technology.

[0003] For the short-circuit protection problem of the OLED device, some solutions have been proposed and applied in the prior art. For example, some protection circuits set current sensing elements on the driving path of the OLED pixel to monitor the current flowing through the OLED device in real time, and when the detected current exceeds a preset fixed threshold, it is judged that a short circuit occurs and the protection mechanism is triggered, such as cutting off the power supply of the faulty pixel. Some other technical solutions attempt to indirectly determine whether a short circuit exists by monitoring the change of the driving voltage or using a specific test signal. At the array substrate level, some technical solutions also attempt to design a specific pixel circuit structure to limit the fault current or isolate the fault area when a short circuit occurs.

[0004] Although the prior art can provide protection for the short circuit phenomenon of the OLED device to some extent, there are still some deficiencies: the accuracy and sensitivity of the short circuit fault detection of the prior art are often difficult to achieve the ideal state. This is mainly because many schemes rely on fixed current thresholds for judgment. However, the normal working current of the OLED device itself will dynamically change with factors such as driving data (i.e., display content), slight fluctuations in driving voltage, and ambient temperature, and it is difficult to accurately define the boundary between normal fluctuations and early short circuits with a fixed threshold. If the threshold is set too high, early or slight short circuits may be missed, allowing them to develop into more serious faults; if the threshold is set too low, normal current peaks may be misjudged as short circuits, resulting in unnecessary protection actions. In addition, the OLED device has an inherent aging effect, and its electrical characteristics will change over time, but the judgment criteria of most existing protection mechanisms do not fully consider and dynamically adapt to the impact of this aging, resulting in a gradual decrease in the accuracy of protection as the device ages. The prior art has limited ability to implement early warning of short circuit risks and take graded response measures. Most schemes mainly respond to obvious short circuits that have already occurred, and usually take a single and hard protection measure such as direct shutdown. The reason is that traditional detection methods may not be able to effectively capture and analyze the subtle but indicative dynamic characteristics of the current at the eve or early stage of short circuit, such as the short-term rapid change rate of the current or the abnormal fluctuation amplitude. Due to the lack of deep analysis and comprehensive evaluation capability of these early characteristics, the system is difficult to issue an early warning before the fault causes significant damage, and it is also difficult to implement differentiated and more targeted protection strategies according to the actual severity of the short circuit risk. Therefore, the prior art still has limitations in contributing to the improvement of the long-term operation reliability of the OLED device and the effective extension of its service life. Short circuit faults that are not accurately and timely identified and properly handled, even if they are initially slight, can accelerate material degradation, accumulate damage, and ultimately lead to premature failure or significant performance degradation of the device. If the protection mechanism cannot accurately limit the fault to the smallest unit, there is a risk of fault spreading. Furthermore, most existing protection strategies lack effective adaptive optimization and intelligent management capabilities. Key parameters in the protection circuit, such as judgment thresholds or internal model parameters, are often fixed after the product is shipped, or require complex manual intervention to adjust. SUMMARY

[0005] The purpose of the present application is to provide a short circuit protection circuit, an array substrate, a display device, and a short circuit protection method, which solve the problems of insufficient short circuit detection accuracy and sensitivity, lack of early warning capability, and difficulty in adaptive optimization of protection strategies in the prior art OLED short circuit protection schemes due to reliance on static thresholds, failure to fully consider device dynamic operating characteristics and aging effects, and lack of effective analysis of current timing characteristics.

[0006] To achieve the above object, the present application is implemented by the following technical solutions: The first aspect of the present application provides a short-circuit protection circuit for an organic light-emitting diode (OLED) device, comprising: An information sensing module configured to acquire an actual working current of the OLED device and at least one real-time parameter related to a working state of the OLED device; A dynamic expectation calculation module connected to the information sensing module and configured to calculate a dynamic expected working current of the OLED device based on the real-time parameter and a preset OLED electrical characteristic model; A decision module connected to the information sensing module and the dynamic expectation calculation module and configured to generate a decision signal for indicating whether the OLED device is in a short-circuit risk state based on the actual working current, the dynamic expected working current, and a short-term change rate and / or fluctuation amplitude extracted from the actual working current; A response control module connected to the decision module and configured to perform a preset protection operation on a driving circuit of the OLED device when the decision signal indicates that the OLED device is in the short-circuit risk state.

[0007] Preferably, the at least one real-time parameter related to the working state of the OLED device acquired by the information sensing module comprises: A driving data and / or driving voltage for driving the OLED device and a local temperature of the OLED device.

[0008] Preferably, the dynamic expectation calculation module comprises: The OLED electrical characteristic model further uses an aging factor, which is a parameter representing an aging degree of the OLED device; The OLED electrical characteristic model is used to represent a corresponding relationship between an expected working current of the OLED device and the real-time parameter and a device aging parameter in a healthy state.

[0009] Preferably, the decision module comprises: The actual working current, the dynamic expected working current, and the extracted short-term change rate and / or fluctuation amplitude are weighted and fused to obtain a comprehensive abnormality score The decision signal is generated according to a comparison result of the comprehensive abnormality score and a preset threshold.

[0010] The second aspect of the present application provides an array substrate comprising a plurality of pixel units and the short-circuit protection circuit described above, wherein each of the pixel units is coupled to a corresponding short-circuit protection circuit.

[0011] The third aspect of the present application provides a display device comprising: The array substrate as described above; and a system-level controller module in communication with the short-circuit protection circuit on the array substrate, the system-level controller module configured to: provide initialization parameters to the short-circuit protection circuit, the initialization parameters comprising initial parameters of the OLED electrical characteristic model; receive feedback information from the short-circuit protection circuit related to the short-circuit risk state of the OLED device; update an aging factor used in the OLED electrical characteristic model based on historical short-circuit risk event information received from the short-circuit protection circuit, and issue the updated aging factor to the dynamic expectation calculation module in the short-circuit protection circuit; based on the feedback information, dynamically adjust a preset threshold used by a decision module in the short-circuit protection circuit to generate a decision signal or a weight used by the decision module in the short-circuit protection circuit for weighted fusion processing.

[0012] The fourth aspect of the present application provides a short-circuit protection method comprising the following steps: S1, obtaining an actual working current of the OLED device and at least one real-time parameter related to the working state of the OLED device; S2, calculating a dynamic expected working current of the OLED device based on the real-time parameter and a preset OLED electrical characteristic model; S3, generating a decision signal for indicating whether the OLED device is in a short-circuit risk state based on the actual working current, the dynamic expected working current, and at least one time sequence feature extracted from the actual working current; S4, when the decision signal indicates that the OLED device is in a short-circuit risk state, performing a preset protection operation on a driving circuit of the OLED device.

[0013] Preferably, the step of obtaining the at least one real-time parameter related to the working state of the OLED device comprises: receiving driving data for driving the OLED device from a pixel driving circuit or a system controller; and / or receiving an anode driving voltage for driving the OLED device from a power supply circuit or sensing the anode driving voltage at an anode terminal of the OLED device; In the step of calculating the dynamic expected working current of the OLED device, the OLED electrical characteristic model further uses an aging factor, which is a parameter representing the aging degree of the OLED device.

[0014] Preferably, the step of generating a decision signal indicative of whether the OLED device is in a short-circuit risk state comprises: extracting at least one time-series feature from the actual operating current, the time-series feature comprising a short-term change rate of the actual operating current and / or a fluctuation amplitude of the actual operating current; performing a weighted fusion process on the actual operating current, the dynamic expected operating current and the at least one time-series feature to obtain a comprehensive abnormality score; generating the decision signal according to a comparison result of the comprehensive abnormality score and a preset threshold.

[0015] Preferably, the method further comprises the following steps: recording event information related to the OLED device being in a short-circuit risk state; periodically or event-drivenly updating the aging factor used in the OLED electrical property model and / or adjusting the preset threshold used in the generation of the decision signal or the weight used in the weighted fusion process based on the recorded event information.

[0016] In summary, the present application comprises at least one of the following beneficial technical effects: 1. The present application dynamically calculates the expected operating current under the current working condition by real-time acquisition of the operating current of the OLED device and multiple working state parameters including driving data and driving voltage, and combining an OLED electrical property model considering the aging effect of the device. This dynamic reference can more accurately reflect the normal behavior of the device in a healthy state, so that when the actual current deviates from this dynamic expectation, combined with the short-term change rate and fluctuation amplitude extracted from the actual current, a comprehensive judgment can be made to more accurately and sensitively identify potential short-circuit risks, effectively reducing false positives and false negatives caused by traditional fixed thresholds or single parameter judgments.

[0017] 2. The present application not only simply judges whether a short-circuit has occurred, but also performs a weighted fusion process on the actual operating current, the dynamic expected operating current and key time-series features to obtain a comprehensive abnormality score. Comparing this score with multiple preset thresholds can more finely classify the short-circuit risk state of the OLED device, such as distinguishing between a warning state, a slight short-circuit or a serious short-circuit. This graded judgment allows the system to issue a warning at an early stage of short-circuit failure development, and to take appropriate and escalating protection operations according to the risk level, rather than shutting down in all cases, thereby providing the possibility for early intervention and flexible handling of failures.

[0018] 3.The present application can significantly reduce the damage to OLED devices, pixel driving circuits, and even entire display devices caused by short-circuit current that is not detected or not handled in time by timely and accurate monitoring and effective protection of potential short-circuit risks of OLED devices. Early isolation of faults or limitation of abnormal current can effectively prevent device burnout, accelerated performance degradation, or trigger a larger range of chain failures, thereby ensuring stable operation of OLED devices throughout their life cycle and prolonging the overall service life of the display device.

[0019] 4.The method and device of the present application include a mechanism for dynamically adjusting key parameters based on historical short-circuit risk event information. For example, the system can periodically or event-drivenly update the aging factor used in the OLED electrical property model based on recorded event information, so that the calculation of the expected current can better match the actual aging state of the device. At the same time, the preset threshold for generating the decision signal in the decision module or the weight used in the weighted fusion process can also be adjusted. This adaptive optimization capability enables the short-circuit protection strategy to continuously learn and evolve, adapting to changes in characteristics under different device batches, different aging stages, and different working environments, thereby maintaining long-term protection effectiveness.

[0020] 5.The present application ensures that each OLED pixel unit in the display device can work in a safer environment through an intelligent and fine short-circuit protection mechanism. This not only reduces the probability of bad pixels, bright lines, or screen function abnormalities caused by short circuits, ensuring the quality and uniformity of the display image, but also reduces user maintenance difficulties and service interruptions due to improved device reliability. A continuous, stable, and high-quality display effect directly improves the overall viewing experience of users and their satisfaction with the product. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 a schematic diagram of the short-circuit protection circuit of the present application; Figure 2 a schematic diagram of the method flow of the present application. DETAILED DESCRIPTION

[0022] The following will be described in detail below in conjunction with the accompanying Figure 1 - the accompanying drawings Figure 2 , the present application will be further described in detail.

[0023] The present application provides a short-circuit protection circuit for an organic light-emitting diode device, which can monitor the working state of the OLED device in real time, dynamically evaluate its short-circuit risk, and execute corresponding protection measures according to the evaluation results.

[0024] As shown in Figure 1 , the short-circuit protection circuit mainly includes: an information sensing module configured to obtain an actual working current of the OLED device and at least one real-time parameter related to the working state of the OLED device; The core function of the information sensing module is to capture the key working parameters of the OLED device in real time and accurately.

[0025] In one aspect, the module is configured to obtain the actual working current of the OLED device. Specifically, a precise sampling resistor can be connected in series in the current path of the OLED device, the voltage difference across the sampling resistor is measured, and an analog-to-digital converter (ADC) is used for conversion, thereby obtaining a quantized value reflecting the current flowing through the OLED device at the moment, denoted as I actual (t). In order to capture the dynamic characteristics of the current, the current sampling can be continuous or at a sufficiently high frequency, thereby forming a series of discrete current sampling points within a certain short time window, constituting the time series data of the actual working current.

[0026] On the other hand, the information sensing module is also configured to obtain at least one real-time parameter related to the working state of the OLED device. These real-time parameters are important basis for subsequent dynamic expectation calculation and accurate decision-making.

[0027] These real-time parameters can include: driving data for driving the OLED device, which is usually provided by the logic control unit of the pixel driving circuit or the system controller (such as the timing controller) at a higher level, and is directly related to the target gray scale or brightness of the OLED pixel.

[0028] Driving voltage for driving the OLED device, especially anode driving voltage V anode The voltage value can be directly obtained from the stable power supply line for the anode of the OLED, or in some precise implementations, it can be sensed in real time by setting a voltage sensing unit near the anode end of the OLED device.

[0029] And the local temperature T local of the OLED device. In some embodiments, a micro temperature sensor such as a thermistor or a PN junction-based temperature sensor can be integrated near the OLED pixel unit or inside the short circuit protection circuit. The purpose of obtaining the local temperature T local is that the electrical characteristics (such as current-voltage relationship, luminous efficiency) of the OLED device are sensitive to temperature. Taking temperature as an input parameter helps to perform temperature compensation when calculating the expected working current subsequently, thereby improving the accuracy of the model.

[0030] The dynamic expectation calculation module is connected with the information perception module and is configured to calculate a dynamic expected working current of the OLED device based on real-time parameters and a preset OLED electrical characteristic model. The dynamic expectation calculation module is connected with the information perception module and is configured to calculate a dynamic expected working current of the OLED device based on real-time parameters and a preset OLED electrical characteristic model.

[0031] The dynamic expectation calculation module is connected with the information perception module and is configured to calculate a dynamic expected working current of the OLED device based on real-time parameters and a preset OLED electrical characteristic model.

[0032] The model can be specifically expressed as a function relationship: I expected =f(L,V anode ,T local ,P ageing ); Wherein: I expected is the calculated dynamic expected working current; L is the driving data acquired by the information perception module; V anode is the anode driving voltage acquired by the information perception module; T local is the local temperature acquired by the information perception module (if the parameter is used); and P ageing is a device aging factor.

[0033] The OLED electrical characteristic model further uses the aging factor, which is a parameter representing the degree of electrical performance degradation of the OLED device due to long-time working. For example, the current of the OLED device under the same driving condition may change as the OLED device ages, and the introduction of the aging factor can enable the model to adapt to such changes. The initial value of the aging factor P ageing may be set according to the device factory characteristics, and can be updated and adjusted by the system-level controller according to the actual operation history of the device in the subsequent stage.

[0034] The specific form of the function f can be a polynomial equation derived based on the physical mechanism of the device, can be an empirical formula fitted through a large amount of experimental data, or can be a multi-dimensional lookup table (LUT) that stores corresponding expected current values under different parameter combinations. The dynamic expectation calculation module will acquire the real-time parameters L, V anode , T local and the current effective aging factor P ageingAs input, by performing the operation of the above model function f, the dynamic expected working current I under the current working condition is obtained expected . This I expected value will serve as a dynamic reference for the subsequent decision module to determine whether the actual current is abnormal.

[0035] The decision module is connected with the information perception module and the dynamic expectation calculation module, and is configured to generate a judgment signal for indicating whether the OLED device is in a short-circuit risk state based on the actual working current, the dynamic expected working current, and the short-term change rate and / or fluctuation amplitude extracted from the actual working current. The decision module has input terminals connected with the output terminals of the information perception module (for obtaining the actual working current I actual (t)) and the dynamic expectation calculation module (for obtaining the dynamic expected working current I expected ). The module is the core intelligent unit of the short-circuit protection circuit, responsible for comprehensive analysis of various input information to determine whether the OLED device is currently at risk of short-circuit, and accordingly generates a corresponding judgment signal. Its working process can include the following aspects: First, key timing features reflecting the dynamic behavior of the current are extracted from the actual working current time series I actual (t) obtained from the information perception module. These timing features at least include the short-term change rate and / or fluctuation amplitude.

[0036] The short-term change rate aims to capture the rapid rising trend of the current in a short time, which is often one of the significant characteristics of short-circuit occurrence. For example, it can be approximated by calculating the average change rate of the current within a preset short time window, or the first-order difference value of the current sequence. A positive change rate far exceeding the normal range may indicate that a short-circuit is occurring or about to occur.

[0037] The fluctuation amplitude aims to quantify the instability or oscillation degree of the current in a short time. For example, the standard deviation, variance, peak-to-peak value, or root mean square value of the current sequence within a short time window can be calculated. When the OLED device experiences early short-circuit or unstable short-circuit, its actual current may exhibit abnormal jitter, spikes, or irregular fluctuations, resulting in a significant increase in fluctuation amplitude.

[0038] The purpose of extracting these timing features is to separate specific patterns related to short-circuit failure from complex current signals, thereby improving the sensitivity and accuracy of detection and effectively distinguishing between normal load changes and abnormal short-circuit behavior.

[0039] Secondly, the decision module is configured to compare the actual working current (or its deviation ΔI = I actual -I expected), the dynamic expected working current itself (a representation as a reference benchmark), and the short-term change rate and / or fluctuation amplitude extracted from the actual working current, etc. are weighted and fused to obtain a comprehensive abnormality score S anomaly The purpose of this weighted fusion processing is to comprehensively consider various possible abnormality-indicating evidence, avoid single-feature misjudgment, and improve the robustness of decision-making. For example, the following linear weighted summation method can be used to calculate the comprehensive abnormality score: S anomaly = w0·eval0(ΔI) + w1·eval1(short-term change rate) + w2·eval2(fluctuation amplitude); Where w0, w1, w2 are weight coefficients corresponding to the information dimensions, which can be pre-set according to the importance of different features for short-circuit indication, or dynamically optimized and adjusted by the system-level controller according to historical data and operation feedback in a more advanced system. The function eval0(·) represents the normalization processing or conversion to the abnormality degree metric of each information dimension or its original feature value. For example, eval0(ΔI) is the absolute value of ΔI or its deviation from a certain normal range.

[0040] Finally, the decision module compares the calculated comprehensive abnormality score S anomaly with one or more pre-set threshold values, and generates a decision signal indicating whether the OLED device is in a short-circuit risk state based on the comparison result. For example, at least one severe short-circuit threshold Th severe can be set. When S anomaly ≥ Th severe , the decision signal indicates that the OLED device is in a severe short-circuit risk state. In a more refined implementation, multiple threshold values of different levels can also be set, such as a warning threshold Th warn and a slight short-circuit threshold Th minor , so as to realize the graded decision of the short-circuit risk state (e.g., normal, warning, slight short-circuit, severe short-circuit), and this decision signal is then transmitted to the subsequent module.

[0041] The response control module is connected with the decision module and is configured to perform a pre-set protection operation on the driving circuit of the OLED device when the decision signal indicates that the OLED device is in a short-circuit risk state. The response control module is connected with the decision module and is configured to perform a pre-set protection operation on the driving circuit of the OLED device when the decision signal indicates that the OLED device is in a short-circuit risk state.

[0042] When the decision signal indicates that the working state of the OLED device is normal, the response control module does not take intervention action, and the OLED device continues its normal display work.

[0043] When the decision signal indicates that the OLED device is in a short-circuit risk state, the response control module will then start the corresponding protection mechanism according to the risk level indicated by the decision signal (if a graded decision is implemented) or the confirmation of the risk occurrence.

[0044] These preset protection operations can include: For the case of a serious short-circuit risk, the response control module can immediately drive a switching element (such as a dedicated protection TFT or an external switching device) connected in series with the OLED device (or the pixel unit where it is located) to act, so as to quickly cut off the current path to the OLED device, preventing the device from being burned out, the driving circuit from being damaged, or even causing a larger range of system failures due to continuous overcurrent.

[0045] For the case of a lower-level risk state (such as a warning or a slight short circuit), the protection operation can be more flexible, for example, it can include: First, record the current event information (including time, working parameters, scores, decision levels, etc.), and report this information to the system-level controller; or, try to take some flexible suppression measures, such as temporarily reducing the upper limit of the driving current or the display brightness of the OLED device, to observe its subsequent behavior or delay the deterioration of the fault.

[0046] In summary, the short-circuit protection circuit provided in the embodiment obtains real-time multi-dimensional working information of the OLED device through the information perception module, establishes a health benchmark that changes with working conditions and aging changes using the dynamic expectation calculation module, then makes intelligent judgments by the decision module in combination with time sequence feature analysis and multi-information fusion, and finally executes appropriate protection actions by the response control module. The whole process forms a closed-loop monitoring and protection mechanism, aiming to improve the reliability of the OLED device operation.

[0047] The application also provides an array substrate comprising a plurality of pixel units and a short-circuit protection circuit as described above, wherein each pixel unit is coupled with a corresponding short-circuit protection circuit; Through this one-to-one coupling mode, each independent short-circuit protection circuit can be responsible for the safety of its corresponding pixel unit and monitor and protect it independently and uninterruptedly. Compared with the traditional scheme of unified protection for the entire panel or a large area, this scheme can detect and isolate early faults of individual pixels earlier, avoiding chain reactions caused by local problems.

[0048] By tightly coupling and integrating the short-circuit protection circuit with the ability of dynamic monitoring, intelligent decision-making and instant response with each pixel unit, a distributed and refined protection network is constructed. This enables the display device to quickly and accurately locate and isolate the short-circuit risk that may occur in a single OLED pixel unit, thereby effectively improving the reliability, safety and long-term stability of the entire display device.

[0049] The present application also includes a display device mainly comprising an array substrate and a system-level controller module; in the display device startup, panel initial power-on or specific maintenance mode, the system-level controller module is responsible for issuing initial configuration parameters to each or each group of short-circuit protection circuits on the array substrate. The initialization parameters are a prerequisite to ensure that each short-circuit protection circuit can start correctly and work effectively.

[0050] These initialization parameters preferably include an initial parameter set of the OLED electrical characteristic model. This includes the coefficients of the model function, the initial content of the lookup table (LUT) or the reference constants of the empirical formula.

[0051] In addition, the initialization parameters can also include the initial aging factor of the OLED device corresponding to each pixel. Further, the initialization parameters can also include the initial weight coefficients used by the decision module in the short-circuit protection circuit for weighted fusion processing, and the initial preset threshold value for generating the judgment signal. By providing these accurate initialization parameters, it can be ensured that the short-circuit protection system has a reasonable working reference based on the initial characteristics of the device at the beginning of operation.

[0052] The system-level controller module continuously or periodically collects feedback information from each short-circuit protection circuit on the array substrate. This feedback mechanism enables the system-level controller to master the health status and potential risk points of the entire display device in real time.

[0053] The feedback information can include the judgment signal (for example, normal, pre-warning, slight short-circuit, serious short-circuit, etc. status code) generated by the decision module of each short-circuit protection circuit, indicating the short-circuit risk state of its corresponding OLED device.

[0054] Collecting these feedback information, on the one hand, is used for instant fault alarm or system-level response, and on the other hand, also accumulates valuable data for subsequent parameter adaptive adjustment.

[0055] The electrical characteristics of an OLED device will age and degrade over time, and the aging rate of different pixel units can be different. In order to maintain the accuracy of the short-circuit protection system (especially the dynamic expected current calculation), the system-level controller module is configured with the function of adaptive updating of the aging factor. Specifically, the system-level controller module will periodically analyze the historical short-circuit risk event information collected from each short-circuit protection circuit. For example, it can count the frequency, severity, etc. of the pre-warning or short-circuit failure of a specific pixel unit or a specific area. Based on these historical data, the system-level controller module can assess the aging degree of each OLED device through built-in algorithms (such as statistical inference models, simple cumulative effect models, or more complex machine learning algorithms), and update the aging factor used in the OLED electrical characteristic model accordingly. The updated aging factor will be issued by the system-level controller module to the dynamic expectation calculation module in the corresponding short-circuit protection circuit on the array substrate through the communication interface. The dynamic expectation calculation module will use this updated aging factor when calculating I expected in the future, so that the reference of the expected current can be closer to the actual aging state of the device, improve the accuracy of short-circuit detection, and reduce the probability of being misjudged as a short circuit due to normal aging of the device.

[0056] Based on the overall feedback information received from all or part of the short-circuit protection circuits (such as the average failure rate of the entire display device over a period of time, the false alarm rate statistics (if it can be assisted by other means), the concentration of pre-warning events under certain image content or working mode, etc.), the system-level controller module can dynamically adjust the key parameters of the decision module distributed in each short-circuit protection circuit. These adjustable parameters can include: the preset threshold value used to compare the comprehensive abnormal score to generate the judgment signal. For example, if the requirement for reliability is extremely high in some application scenarios, the threshold value can be appropriately lowered to improve the detection sensitivity; on the contrary, if the false alarm rate is found to be too high, the threshold value can be appropriately increased under the premise of ensuring safety. At the same time, the adjustable parameters can also include the weight coefficients of each feature used by the decision module in the weighted fusion processing. This dynamic adjustment enables the short-circuit protection strategy to seek the best balance between false alarm rate and missed alarm rate while ensuring the effectiveness of protection.

[0057] The short-circuit protection method described below can be mutually corresponding with the short-circuit protection circuit described above.

[0058] Please refer to the accompanying Figure 2 , the present application also provides a short-circuit protection method, comprising the following steps: First, the step of obtaining the actual working current of the OLED device and at least one real-time parameter related to the working state of the OLED device is performed.

[0059] This step is the data input link of the whole protection method, its accuracy and real-time directly affect the reliability of the subsequent judgment.

[0060] Obtaining the actual working current I of the OLED device actual (t), which is usually achieved by deploying a current sensing element (e.g. a precision sampling resistor) in the power supply loop of the OLED device and cooperating with an analog-to-digital converter (ADC). By continuously or quasi-continuously quantifying and collecting the current flowing through the OLED device at a sufficiently high sampling frequency, current time series data reflecting the real-time load condition can be obtained.

[0061] At the same time, the step of obtaining at least one real-time parameter related to the working state of the OLED device can specifically include: receiving target driving data L for driving the OLED device from the pixel driving circuit or a higher-level system controller (e.g. timing controller TCON). The driving data usually corresponds to the expected pixel luminance level and is one of the key factors affecting the normal working current of the OLED device.

[0062] And / or receiving the anode driving voltage V anode for driving the OLED device from the power supply line or sensing it at the anode end of the OLED device. The stability of the anode driving voltage directly affects the current through the OLED device, so its real-time value is crucial for accurate modeling. The acquisition method can be to directly read the known stable power supply voltage value, or to measure it on site through a specially designed voltage sensor.

[0063] In some preferred embodiments, the real-time parameters can also include the local temperature T local of the OLED device, which can be obtained by a temperature sensor integrated near the device or in the protection circuit. Considering that the electrical characteristics of OLED are relatively sensitive to temperature, introducing the temperature parameter helps to improve the accuracy of the subsequent expected current calculation. These real-time parameters together constitute a comprehensive description of the current working environment and driving state of the OLED device.

[0064] Then, the step of calculating the dynamic expected working current of the OLED device based on the real-time parameters and the preset OLED electrical characteristic model is performed. The purpose of this step is to establish a dynamic "healthy" current reference I expected . This step relies on a preset OLED electrical characteristic model, which aims to mathematically represent the intrinsic relationship between the expected working current of the OLED device and its real-time working parameters (such as the driving data, anode driving voltage, local temperature mentioned above) and the aging state of the device itself under the condition of being healthy and free of short circuit risk.

[0065] In the step of calculating the dynamic expected working current of the OLED device, the OLED electrical characteristic model further uses an aging factor P ageing . The aging factor is a parameter for quantitatively characterizing the degree of electrical performance degradation of the OLED device due to long-term use. The aging of the OLED device causes changes in its current response under the same driving conditions. By introducing and dynamically updating this aging factor, the electrical characteristic model can better track and compensate for this aging effect.

[0066] Therefore, the calculation of the dynamic expected working current I expected can be represented as a function relationship as follows: I expected = f(L, V anode , T local , P ageing ); wherein I expected is the calculated dynamic expected working current; L is the driving data obtained by the information perception module; V anode is the anode driving voltage obtained by the information perception module; T local is the local temperature obtained by the information perception module (if this parameter is used); and P ageing is a device aging factor.

[0067] Subsequently, a step of generating a decision signal for indicating whether the OLED device is in a short-circuit risk state based on the actual working current, the dynamic expected working current, and at least one timing feature extracted from the actual working current is performed. This step is the core link of risk assessment and decision-making, which comprehensively judges by comparing the actual behavior with the expected behavior and combining the dynamic characteristics of the current.

[0068] The step of generating the decision signal can specifically include the following sub-steps: Extracting at least one timing feature from the actual working current.

[0069] In order to more deeply understand the dynamic behavior of the current and identify early signs or unique patterns of short circuits, it is necessary to extract key timing features from the obtained actual working current time series I actual (t). The timing features preferably include the short-term change rate of the actual working current and / or the fluctuation amplitude of the actual working current. The short-term change rate, such as the average rate of increase or the instantaneous derivative (which can be approximated by differentiation) of the current within a short time window, can effectively capture the rapid and abnormal rise of the current.

[0070] The fluctuation amplitude, such as the standard deviation, peak-to-peak value, or variance of the current within a short time window, can quantify the degree of instability of the current. In the early stage or development process of a short circuit, the current may exhibit abnormal jitter, spikes, or irregular oscillations, resulting in a significant deviation of the fluctuation amplitude from the normal range.

[0071] The significance of extracting these timing features is that they can provide additional information dimensions beyond simple current amplitude comparison, helping to distinguish normal current fluctuations (e.g. caused by image content changes) from abnormal dynamics indicating potential short-circuit risks.

[0072] The actual working current, the dynamic expected working current itself, and at least one extracted timing feature are weighted and fused to obtain a comprehensive abnormality score S anomaly .

[0073] In order to form a comprehensive and robust short-circuit risk assessment, it is necessary to effectively integrate information from different dimensions. Weighted fusion processing is for this purpose, for example, linear weighted sum can be used: S anomaly = w0·eval0(ΔI) + w1·eval1(short-term change rate) + w2·eval2(fluctuation amplitude); Where w0, w1, w2 are weight coefficients corresponding to the information dimensions, which can be pre-set according to the importance of different features to short-circuit indication, or dynamically optimized and adjusted by the system-level controller according to historical data and operation feedback in a more advanced system. Function eval0(·) represents the normalization processing or conversion of each information dimension or its original feature value to its abnormality degree measure quantization function. For example, eval0(ΔI) is the absolute value of ΔI or its deviation from a certain normal range. Through this step, multiple scattered observation indicators can be converged into a single, quantitative comprehensive abnormality score.

[0074] According to the comparison result of the comprehensive abnormality score and one or more pre-set threshold values, a decision signal is generated. The calculated comprehensive abnormality score S anomaly is compared with a series of pre-set threshold values. According to which threshold interval S anomaly falls into, the corresponding decision signal is generated. The decision signal clearly indicates whether the OLED device is currently in a short-circuit risk state and the possible risk level (e.g. normal state, pre-warning, slight short-circuit, serious short-circuit).

[0075] Then, when the decision signal indicates that the OLED device is in a short-circuit risk state, a pre-set protection operation is performed on the driving circuit of the OLED device.

[0076] This step is the risk response and disposal link. Once it is determined that the OLED device has a short-circuit risk, measures must be taken in time to avoid or mitigate damage.

[0077] The preset protection operation varies according to the risk level indicated by the decision signal. For example, if a serious short-circuit risk is determined, the protection operation can be to immediately cut off the power supply loop of the OLED device, for example by controlling a series-connected switching element (such as a TFT) to open, to prevent the device from being burned out, the driving circuit from being damaged, or the normal work of other parts of the panel from being affected due to the continuous excessive current.

[0078] If a lower-level risk (such as a warning or a slight short-circuit) is determined, the protection operation can be more moderate, for example, first recording detailed event information and reporting to the system-level controller, or trying to take some suppression measures, such as temporarily reducing the upper limit of the driving current or the display brightness of the OLED device, to observe the subsequent state or delay the further development of the failure.

[0079] Finally, the short-circuit protection method of the embodiment preferably further includes the following steps for adaptive optimization: Recording event information related to the short-circuit risk state of the OLED device.

[0080] When the OLED device is determined to have any level of short-circuit risk state (from warning to serious short-circuit), the system automatically or with the intervention of the operator records detailed information related to the event. These information can include: the timestamp of the event occurrence, the accurate pixel position information, the working parameters (actual current, expected current, driving data, driving voltage, temperature, etc.) at the time of risk occurrence, the calculated comprehensive abnormal score, the extracted time sequence feature values, the final decision signal content, and the specific protection operation performed, etc.

[0081] Based on the recorded event information, periodically or event-drivenly update the aging factor used in the OLED electrical property model, and / or adjust the preset threshold used in generating the decision signal or the weight used in the weighted fusion processing. This step embodies the adaptive learning and evolution ability of the method. Through the analysis of the long-term accumulated event information (for example, performed by the system-level controller), dynamic optimization of the protection strategy parameters can be achieved.

[0082] Updating the aging factor: if the data shows that a particular OLED device or region frequently appears warning or early failure signs, the corresponding aging factor can be adjusted accordingly to better reflect the actual situation of accelerated aging of the device. In this way, the dynamically expected current calculated subsequently can be more accurate, avoiding the normal current change caused by aging from being misjudged.

[0083] Adjusting decision parameters: based on statistical analysis of the overall panel false alarm rate, false alarm situation, or according to the change of short circuit characteristics in a specific application scene, the preset threshold used in the decision module or the weight of each feature in the weighted fusion can be dynamically adjusted. For example, if it is found that a certain timing feature has higher indication for early short circuit, its weight can be increased; if the overall false alarm rate is high, the threshold can be adjusted appropriately under the premise of ensuring safety.

[0084] This periodic or event-driven parameter updating mechanism enables the short circuit protection method to continuously adapt to the changes in the life cycle of OLED devices and the changes in external working conditions, and continuously maintain its protection accuracy and effectiveness.

[0085] The method of the embodiment can be used to implement the short circuit protection circuit described above, which has similar principles and technical effects, and will not be described here.

[0086] Although embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A short-circuit protection circuit for an organic light-emitting diode (OLED) device, characterized in that, include: The information sensing module is configured to acquire the actual operating current of the OLED device and at least one real-time parameter related to the operating state of the OLED device. The dynamic expectation calculation module is connected to the information sensing module and is configured to calculate the dynamic expectation operating current of the OLED device based on the real-time parameters and the preset OLED electrical characteristic model. The decision module, connected to the information sensing module and the dynamic expectation calculation module, is configured to generate a judgment signal indicating whether the OLED device is in a short-circuit risk state based on the actual operating current, the dynamic expectation operating current, and the short-term change rate and / or fluctuation amplitude extracted from the actual operating current. A response control module, connected to the decision module, is configured to perform a preset protection operation on the driving circuit of the OLED device when the determination signal indicates that the OLED device is in a short-circuit risk state.

2. The short-circuit protection circuit according to claim 1, characterized in that, The at least one real-time parameter related to the operating state of the OLED device acquired by the information sensing module includes: The driving data and / or driving voltage of the OLED device and the local temperature of the OLED device.

3. A short-circuit protection circuit according to claim 1, characterized in that, The dynamic expectation calculation module includes: The OLED electrical characteristic model further uses an aging factor, which is a parameter characterizing the degree of aging of the OLED device; The OLED electrical characteristic model is used to characterize the correspondence between the expected operating current of the OLED device and the real-time parameters and device aging parameters under healthy conditions.

4. A short-circuit protection circuit according to claim 1, characterized in that, The decision-making module includes: The actual operating current, the dynamic expected operating current, and the extracted short-term rate of change and / or fluctuation amplitude are weighted and fused to obtain a comprehensive anomaly score. The determination signal is generated based on the comparison result between the comprehensive anomaly score and the preset threshold.

5. An array substrate, characterized in that, It includes multiple pixel units and a short-circuit protection circuit as claimed in any one of claims 1 to 4, wherein each pixel unit is coupled to a corresponding short-circuit protection circuit.

6. A display device, characterized in that, include: The array substrate as described in claim 4; And a system-level controller module, which communicates with the short-circuit protection circuit on the array substrate, wherein the system-level controller module is configured as follows: Initialization parameters are provided to the short-circuit protection circuit, including initial parameters of the OLED electrical characteristic model; Receive feedback information from the short-circuit protection circuit related to the short-circuit risk status of the OLED device; Based on the historical short-circuit risk event information received from the short-circuit protection circuit, the aging factor used in the OLED electrical characteristic model is updated, and the updated aging factor is sent to the dynamic expectation calculation module in the short-circuit protection circuit. Based on the feedback information, the preset threshold used by the decision module in the short-circuit protection circuit to generate the judgment signal or the weight used by the decision module in the short-circuit protection circuit to perform weighted fusion processing are dynamically adjusted.

7. A short-circuit protection method, characterized in that, Includes the following steps: S1. Obtain the actual operating current of the OLED device and at least one real-time parameter related to the operating state of the OLED device; S2. Based on the real-time parameters and the preset OLED electrical characteristic model, calculate the dynamic expected operating current of the OLED device; S3. Based on the actual operating current, the dynamic expected operating current, and at least one timing feature extracted from the actual operating current, generate a determination signal to indicate whether the OLED device is in a short-circuit risk state. S4. When the determination signal indicates that the OLED device is in a short-circuit risk state, a preset protection operation is performed on the driving circuit of the OLED device.

8. A short-circuit protection method according to claim 7, characterized in that, The step of obtaining the at least one real-time parameter related to the operating state of the OLED device includes: Receive driving data for driving the OLED device from the pixel driving circuit or system controller; And / or receive from the power supply line or sense at the anode end of the OLED device an anode driving voltage for driving the OLED device; In the step of calculating the dynamic expected operating current of the OLED device, the OLED electrical characteristic model further uses an aging factor, which is a parameter characterizing the degree of aging of the OLED device.

9. A short-circuit protection method according to claim 7, characterized in that, The step of generating a determination signal to indicate whether the OLED device is in a short-circuit risk state includes: At least one time-series feature is extracted from the actual operating current, the time-series feature including the short-term rate of change of the actual operating current and / or the fluctuation amplitude of the actual operating current; The actual operating current, the dynamic expected operating current, and the at least one timing feature are weighted and fused to obtain a comprehensive anomaly score. The determination signal is generated based on the comparison result between the comprehensive anomaly score and the preset threshold.

10. A short-circuit protection method according to claim 7, characterized in that, The method further includes the following steps: Record event information related to the short-circuit risk state of the OLED device; Based on the recorded event information, the aging factor used in the OLED electrical characteristic model is updated periodically or in an event-driven manner, and / or the preset threshold used when generating the determination signal or the weight used in the weighted fusion process is adjusted.

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