Compensation circuit, display driver chip, display panel and driving method thereof

Abstract

The present application relates to a compensation circuit, a display driver chip, a display panel and a driving method thereof. The compensation circuit includes a compensation module and a driving voltage generation module. The compensation circuit is used to receive the initial driving current output by the pixel circuit to be compensated, and determine the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current, wherein the reference clock pulse data includes the calibration pulse number corresponding to the target driving current output by the pixel circuit to be compensated at different grayscales; the driving voltage generation module is used to generate a target data signal according to the compensation signal during the compensation phase of the pixel circuit to be compensated, and output it to the pixel circuit to be compensated during the data writing phase of the pixel circuit to be compensated; wherein the compensation phase is before the data writing phase. The use of the above-mentioned compensation circuit to compensate the data signal can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a compensation circuit, a display driver chip, a display panel and a driving method thereof. Background Art

[0002] With the continuous development of display panel technology, AMOLED (Active-matrix organic light-emitting diode) has been widely used in consumer electronic products due to its advantages such as wide color gamut, high contrast, low power consumption, and lighter weight.

[0003] However, there are many non-ideal factors in the current AMOLED display panel, which leads to inconsistency in the driving current for driving the light emission between the pixels, making the brightness of the entire display panel uneven, affecting the display effect. Summary of the invention

[0004] Based on this, it is necessary to provide a compensation circuit, a display driver chip, a display panel and a driving method thereof to address the above technical problems, which can improve the brightness uniformity of the display panel and thus improve the display effect.

[0005] In a first aspect, the present application provides a compensation circuit, comprising:

[0006] A compensation module, wherein a first end of the compensation module is used to connect to a pixel circuit to be compensated, the compensation circuit is used to receive an initial driving current output by the pixel circuit to be compensated, and determine a compensation signal according to reference clock pulse data and a current clock pulse number corresponding to the initial driving current, wherein the reference clock pulse data includes a calibrated pulse number corresponding to a target driving current output by the pixel circuit to be compensated at different grayscales;

[0007] A driving voltage generating module, wherein the first end of the driving voltage generating module is connected to the second end of the compensation module, the second end of the driving voltage generating module is connected to the pixel circuit to be compensated, and the driving voltage generating module is used to generate a target data signal according to the compensation signal during the compensation phase of the pixel circuit to be compensated, and output the target data signal to the pixel circuit to be compensated during the data writing phase of the pixel circuit to be compensated; wherein the compensation phase is before the data writing phase.

[0008] The compensation circuit includes a compensation module and a driving voltage generation module. The compensation module receives the initial driving current of the pixel circuit to be compensated during the compensation phase of the pixel circuit to be compensated, and determines the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current. The driving voltage generation module receives the compensation signal and generates a target data signal according to the compensation signal. During the data writing phase of the pixel circuit to be compensated, the driving voltage generation module outputs the target data signal to the pixel circuit to be compensated, so that the pixel circuit to be compensated outputs a new driving current under the target data signal, and then during the light-emitting phase, the new driving current is output to the light-emitting element to drive the light-emitting element to emit light. The new driving current outputted in the above manner has a high consistency, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel to improve the display effect.

[0009] In a second aspect, the present application also provides a display driver chip, comprising the compensation circuit as described above.

[0010] The display driver chip includes a compensation circuit, through which a compensated target data signal can be generated. After the target data signal is output to the pixel circuit to be compensated, the pixel circuit to be compensated can output a new driving current under the target data signal, and then in the light-emitting stage, the new driving current is output to the light-emitting element to drive the light-emitting element to emit light. The new driving current output in the above manner has a high consistency, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel to improve the display effect.

[0011] In a third aspect, the present application further provides a display panel, comprising a pixel circuit and the compensation circuit as described above, wherein the pixel circuit is connected to the compensation circuit.

[0012] The above display panel includes a pixel circuit and a compensation circuit as in the above embodiment. In the compensation stage, the pixel circuit outputs an initial driving current to the compensation circuit, and the compensation circuit receives the initial driving current and generates a compensated target data signal based on the initial driving current. In the data writing stage, the compensation circuit outputs the target data signal to the pixel circuit to be compensated, so that the pixel circuit to be compensated can output a new driving current under the target data signal, and then in the light-emitting stage, the pixel circuit outputs the new driving current to the light-emitting element to drive the light-emitting element to emit light. The new driving current outputted in the above manner has a high consistency, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel to improve the display effect.

[0013] In a fourth aspect, the present application further provides a method for driving a display panel, which is applied to the display panel as described above, and the method for driving a display panel includes:

[0014] In the compensation phase, an initial driving current output by the pixel circuit according to an initial data signal in the initialization phase is obtained;

[0015] Determine a compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current;

[0016] Generate a target data signal according to the compensation signal, wherein the reference clock pulse data includes the calibration pulse number corresponding to the target driving current output by the pixel circuit at different gray scales;

[0017] In the data writing phase, the target data signal is output to the pixel circuit so that the pixel circuit generates a new driving current.

[0018] The driving method of the above-mentioned display panel, in the initialization stage, the driving voltage generation module generates an initial data signal and outputs it to the pixel circuit, and the pixel circuit receives and stores the initial data signal; in the compensation stage, the compensation module receives the initial driving current of the pixel circuit in the compensation stage of the pixel circuit, determines the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current, and the driving voltage generation module receives the compensation signal and generates the target data signal according to the compensation signal. In the data writing stage of the pixel circuit, the driving voltage generation module outputs the target data signal to the pixel circuit, so that the pixel circuit outputs a new driving current under the target data signal, and then in the light-emitting stage, the new driving current is output to the light-emitting element to drive the light-emitting element to emit light. The consistency of the new driving current output by the above-mentioned method is high, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel to improve the display effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 is a schematic diagram of the structure of a compensation circuit in an embodiment of the present application;

[0021] Figure 2 is a schematic structural diagram of a compensation circuit in another embodiment of the present application;

[0022] Figure 3 is a schematic diagram of the structure of a compensation circuit in yet another embodiment of the present application;

[0023] Figure 4 is a schematic diagram of the structure of a compensation circuit in another embodiment of the present application;

[0024] Figure 5 is a schematic diagram of the structure of a display driver chip in an embodiment of the present application;

[0025] Figure 6 is a schematic structural diagram of a display panel in an embodiment of the present application;

[0026] Figure 7 is a schematic structural diagram of a display panel in another embodiment of the present application;

[0027] Figure 8 is a working timing diagram of a pixel circuit in an embodiment of the present application;

[0028] Fig. 9 is a schematic structural diagram of a display panel in yet another embodiment of the present application;

[0029] Fig.10 is a schematic structural diagram of a display panel in yet another embodiment of the present application;

[0030] Fig.11 is a schematic flow chart of a method for driving a display panel in an embodiment of the present application;

[0031] Fig.12 FIG. 4 is a flow chart of a method for driving a display panel in another embodiment of the present application.

[0032] Description of reference numerals:

[0033] 10-compensation circuit, 11-compensation module, 111-sampling circuit, 112-comparison circuit, 113-processing circuit, 12-driving voltage generating module, 20-pixel circuit to be compensated, 100-display driver chip, 200-display panel, 30-pixel circuit, 31-storage module, 32-data writing module, 33-sensing module, 34-light emitting control module. DETAILED DESCRIPTION

[0034] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0036] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0037] In the following embodiments, when a layer, region, or element is "connected", it can be interpreted that the layer, region, or element is not only directly connected but also connected through other constituent elements placed therebetween. For example, when a layer, region, element, etc. is described as being connected or electrically connected, the layer, region, element, etc. can be connected or electrically connected not only directly or directly, but also through another layer, region, element, etc. placed therebetween.

[0038] Hereinafter, although terms such as "first", "second", etc. may be used to describe various components, these components are not necessarily limited to the above terms. The above terms are only used to distinguish one component from another. It will also be understood that expressions used in the singular include plural expressions unless the expression in the singular has an obviously different meaning in the context.

[0039] As used in the application documents, the term "and / or" includes any and all combinations of one or more of the related listed items. It should also be understood that the terms "include / comprise" or "have" etc. specify the existence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the existence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.

[0040] Electronic or electrical devices and / or any other related devices or components according to the embodiments of the concepts of the present application described herein (for example, a display device including a display panel and a display panel driver, wherein the display panel driver also includes a drive controller, a gate driver, a gamma reference voltage generator, a data driver, and an emission driver) can be implemented using any appropriate hardware, firmware (such as a dedicated integrated circuit), software, or a combination of software, firmware, and hardware. For example, the various components of these devices may be formed on an integrated circuit (IC) chip or on separate IC chips. In addition, the various components of these devices may be implemented on a flexible printed circuit film, a tape carrier package (TCP), a printed circuit board (PCB), or formed on a substrate. In addition, the various components of these devices may be processes or threads that run on one or more processors in one or more computing devices to execute computer program instructions and interact with other system components to perform the various functions described herein. The computer program instructions are stored in a memory that can be implemented in a computing device using standard storage devices (e.g., such as random access memory (RAM). The computer program instructions can also be stored in other non-transitory computer-readable media (e.g., such as CD-ROMs, flash drives, etc.). Moreover, those skilled in the art should recognize that the functions of various computing devices can be combined or integrated into a single computing device, or the functions of a particular computing device can be distributed on one or more other computing devices without departing from the spirit and scope of the exemplary embodiments of the concepts of the present application.

[0041] Although exemplary embodiments of display modules and display devices including display modules have been specifically described herein, many modifications and variations will be apparent to those skilled in the art. Therefore, it will be understood that display modules and display devices including display modules constructed according to the principles of the present application may be implemented in addition to those specifically described herein. The present application is also defined in the claims and their equivalents.

[0042] As described in the background technology, there are many non-ideal factors in the current AMOLED display panel that cause the driving current for driving the light emission between each pixel to be inconsistent, making the brightness of the entire display panel uneven, affecting the display effect. For example, limited by the TFT (thin film transistor) manufacturing process on the display substrate, the threshold voltage Vth uniformity is poor, and there is a large threshold voltage offset in the entire panel, which is manifested as a drift in the driving current between each pixel, resulting in uneven display brightness. For another example, the carrier mobility deviation and KINK effect of TFT also cause the driving current to change, thereby affecting the uniformity of image display. For medium and large-sized display panels, the power line introduces a voltage drop due to parasitic resistance, which also affects the uniformity of the light-emitting current between each pixel circuit.

[0043] Based on the above problems, in one embodiment, Figure 1 As shown, the present application provides a compensation circuit 10 , including: a compensation module 11 and a driving voltage generating module 12 .

[0044] The first end of the compensation module 11 is used to connect to the pixel circuit 20 to be compensated, and the compensation circuit 10 is used to receive the initial driving current output by the pixel circuit 20 to be compensated, and determine the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current, wherein the reference clock pulse data includes the calibrated pulse number corresponding to the target driving current output by the pixel circuit 20 to be compensated at different gray scales.

[0045] Among them, the initial driving current is the driving current output by the pixel circuit 20 to be compensated under the initial data signal (the data signal without compensation processing) to drive the light-emitting element to emit light, and the reference clock pulse data includes the calibrated pulse number corresponding to the target driving current output by the pixel circuit 20 to be compensated at different gray scales. Based on the reference clock pulse data, the corresponding calibrated pulse number of the currently predetermined display gray scale can be determined. The current clock pulse number corresponding to the initial driving current is the actual pulse number corresponding to the currently predetermined display gray scale. Based on the calibrated pulse number and the actual pulse number of the currently predetermined display gray scale, the voltage to be compensated can be determined, and then the compensation signal can be determined.

[0046] The first end of the driving voltage generating module 12 is connected to the second end of the compensation module 11, and the second end of the driving voltage generating module 12 is connected to the pixel circuit 20 to be compensated. The driving voltage generating module 12 is used to generate a target data signal according to the compensation signal during the compensation phase of the pixel circuit 20 to be compensated, and output it to the pixel circuit 20 to be compensated during the data writing phase of the pixel circuit 20 to be compensated; wherein the compensation phase is before the data writing phase.

[0047] The initial data signal may be output by the driving voltage generating module 12 to the pixel circuit 20 to be compensated in the initialization phase of the pixel circuit 20 to be compensated, and the initialization phase is before the compensation phase.

[0048] It can be understood that, in the compensation stage of the pixel circuit 20 to be compensated, the pixel circuit 20 to be compensated outputs an initial driving current to the compensation module 11, and the compensation module 11 determines a compensation signal according to the initial driving current, and sends the compensation signal to the driving voltage generating module 12 at the same time, and the driving voltage generating module 12 generates a target data signal according to the compensation signal. In the data writing stage of the pixel circuit 20 to be compensated, the driving voltage generating module 12 outputs the target data signal to the pixel circuit 20 to be compensated, so that the pixel circuit 20 to be compensated outputs a new driving current under the target data signal, and then in the light-emitting stage, the new driving current is output to the light-emitting element, driving the light-emitting element to emit light, so that the actual brightness of the display reaches the current predetermined display grayscale.

[0049] The compensation circuit 10 includes a compensation module 11 and a driving voltage generating module 12. The compensation module 11 receives the initial driving current of the pixel circuit 20 to be compensated during the compensation phase of the pixel circuit 20 to be compensated, and determines the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current. The driving voltage generating module 12 receives the compensation signal and generates a target data signal according to the compensation signal. During the data writing phase of the pixel circuit 20 to be compensated, the driving voltage generating module 12 outputs the target data signal to the pixel circuit 20 to be compensated, so that the pixel circuit 20 to be compensated outputs a new driving current under the target data signal, and then during the light-emitting phase, the new driving current is output to the light-emitting element to drive the light-emitting element to emit light. The new driving current outputted in the above manner has a high consistency, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel to improve the display effect.

[0050] In one embodiment, Figure 2 As shown, the second end of the driving voltage generating module 12 is also connected to the first end of the compensation module 11 .

[0051] It can be understood that since the initial driving current is output by the pixel circuit 20 to be compensated to the compensation module 11 in the compensation stage, and the initial data signal and the target data signal are output by the driving voltage generating module 12 to the pixel circuit 20 to be compensated in the initialization stage and the data writing stage, respectively, the transmission stages of the initial driving current and the data signal are different. Based on this, the second end of the driving voltage generating module 12 is also connected to the first end of the compensation module 11, so that the transmission signal line of the initial driving current and the transmission signal line of the data signal (initial data signal and target data signal) can be the same signal line, that is, the data signal line can be multiplexed as a signal line for transmitting the initial driving current, so that there is no need to set up an additional signal line for transmitting the initial driving current, reducing the number of signal lines, which is conducive to simplifying the routing of the display panel.

[0052] In one embodiment, Figure 3As shown, the compensation circuit 10 includes: a sampling circuit 111 , a comparison circuit 112 and a processing circuit 113 .

[0053] A first terminal of the sampling circuit 111 is used to connect to the pixel circuit 20 to be compensated, a second terminal of the sampling circuit 111 is connected to the common ground, and the sampling circuit 111 is used to receive and store the initial driving current output by the pixel circuit 30 .

[0054] The first input terminal of the comparison circuit 112 is connected to the first terminal of the sampling circuit 111 . The second input terminal of the comparison circuit 112 is used to receive the reference voltage Vref. The comparison circuit 112 is used to output a stop signal when the voltage input to the first input terminal is greater than the reference voltage Vref.

[0055] The first input terminal of the processing circuit 113 is connected to the first terminal of the sampling circuit 111, and the second input terminal of the processing circuit 113 is connected to the output terminal of the comparison circuit 112. The processing circuit 113 is used to count the pulses of the initial driving current, stop counting when receiving a stop signal to obtain the current clock pulse number, and determine the compensation signal according to the pulse number difference between the current clock pulse number and the calibrated pulse number corresponding to the target grayscale.

[0056] The target grayscale may be a currently predetermined display grayscale of the pixel.

[0057] In the application, when determining the reference clock pulse data, corresponding to different grayscale brightness, the corresponding target drive current can be obtained by traversal, and the sampling circuit 111 receives and stores the target drive current; the processing circuit 113 counts the target drive current; the potential of the first end of the acquisition circuit is the same as the potential of the first input end of the comparison circuit 112. When the voltage output by the first end of the sampling circuit 111 is greater than the reference voltage Vref, the comparison circuit 112 outputs a stop signal, and the processing circuit 113 stops counting when receiving the stop signal. The number of pulses recorded by the processing circuit 113 when receiving the stop signal is the calibration pulse number under the current display grayscale. After recording the calibration pulse number under each grayscale, the processing circuit 113 obtains the reference clock pulse data. After recording the calibration pulse number Pij under different grayscale brightness, the calibration pulse number lookup table can be determined according to the calibration pulse number Pij data, where i represents the row where the pixel is located, and j represents the column where the sub-pixel is located. For example, when the display gray scale is 128, the corresponding target driving current is I128_ij, and the calibration pulse number Pij=VREF / I128_ij, where VREF is the reference voltage Vref.

[0058] It can be understood that the first input terminal of the comparison circuit 112 is connected to the first terminal of the sampling circuit 111, and the potential of the first terminal of the acquisition circuit is the same as the potential of the first input terminal of the comparison circuit 112. Then, when the voltage output from the first terminal of the sampling circuit 111 is greater than the reference voltage Vref, the comparison circuit 112 outputs a stop signal, and the processing circuit 113 stops counting when receiving the stop signal. The number of pulses recorded by the processing circuit 113 when receiving the stop signal is the current clock pulse number.

[0059] It can be found that the method of obtaining the current clock pulse number is the same as the method of obtaining the corresponding calibration pulse number, except that the target drive current and the initial drive current are different. Therefore, based on the difference between the current clock pulse number and the calibration pulse number corresponding to the target grayscale, the difference information between the target drive current and the initial drive current can be determined, and the processing circuit 113 can determine the compensation signal according to the current clock pulse number and the reference clock pulse data compensation, so that the driving voltage generation module 12 generates the target data signal according to the compensation signal during the compensation phase of the pixel circuit 20 to be compensated, and outputs it to the pixel circuit 20 to be compensated during the data writing phase of the pixel circuit 20 to be compensated, so that the pixel circuit 20 to be compensated generates the target drive current, and the corresponding light-emitting element is driven to emit light through the target drive current, so that the light-emitting brightness reaches the predetermined grayscale brightness.

[0060] In one embodiment, Figure 4 As shown, the sampling circuit 111 includes: a first selection switch U1, a first capacitor Cdet and a first discharge switch U3.

[0061] The first end of the first selection switch U1 is used to connect to the pixel circuit 20 to be compensated, and is used to receive the initial driving current output by the pixel circuit 30. The first end of the first capacitor Cdet is connected to the second end of the first selection switch U1, and the second end of the first capacitor Cdet is connected to the common ground. The first end of the first discharge switch U3 is connected to the first end of the first capacitor Cdet, and the second end of the first discharge switch U3 is connected to the common ground. In the compensation stage, the first selection switch U1 is turned on and the first discharge switch U3 is turned off; in the data writing stage, the first selection switch U1 is turned off.

[0062] In the application, a discharge stage can be set before the compensation stage. In the discharge stage, the first discharge switch U3 is turned on, the first end of the first capacitor Cdet is connected to the common ground, and the first capacitor Cdet is discharged to the ground. In the compensation stage, the first selection switch U1 is turned on, the first discharge switch U3 is turned off, and the first capacitor Cdet receives and stores the initial drive current. While the first capacitor Cdet receives and stores the initial drive current, the processing circuit 113 starts counting until the comparison circuit 112 outputs a stop signal. The processing circuit 113 stops counting when the stop signal is received, and determines the recorded number of pulses as the current number of clock pulses, thereby obtaining the current number of clock pulses.

[0063] In one embodiment, Figure 4 As shown, the comparison circuit 112 includes: a comparator U5 and a logic control unit U6.

[0064] The first input terminal of the comparator U5 is connected to the first terminal of the sampling circuit 111, the second input terminal of the comparator U5 is used to receive the reference voltage Vref, the first input terminal of the comparator U5 is used to receive the voltage output by the first terminal of the sampling circuit 111, and the comparator U5 is used to output a first logic signal when the input signal voltage of the first input terminal of the comparison circuit 112 is greater than the reference voltage Vref, and output a second logic signal when the input signal voltage of the first input terminal of the comparison circuit 112 is less than the reference voltage Vref.

[0065] It can be understood that the comparator U5 can compare the voltage of the first input terminal with the voltage of the second input terminal, and output a corresponding logic signal according to the comparison result. In the compensation stage, as the sampling circuit 111 receives and stores the initial driving current, the voltage output from the first terminal of the sampling circuit 111 gradually increases, and the first input terminal of the comparator U5 is used to receive the voltage output from the first terminal of the sampling circuit 111, then the voltage received by the first input terminal of the comparator U5 also gradually increases until the input signal voltage at the first input terminal of the comparison circuit 112 is greater than the reference voltage Vref, at which time the comparator U5 outputs the first logic signal.

[0066] The logic control unit U6 is connected to the output end of the comparator U5, and the logic control unit U6 is used to output a stop signal when receiving the first logic signal.

[0067] It can be understood that when the output signal of the comparator U5 changes, the logic control unit U6 receives the first logic signal and outputs a stop signal, and the processing circuit 113 receives the stop signal and stops counting. Then, the processing circuit 113 can stop counting when the output signal of the comparator U5 changes, thereby obtaining the current number of clock pulses based on the reference voltage Vref. Similarly, the calibration pulse number is also determined in the above manner, except that the calibration pulse number corresponds to the target drive current under the target grayscale, and the current clock pulse number corresponds to the initial drive current. Based on the pulse number difference between the calibration pulse number and the current clock pulse number, the difference between the target drive current and the initial drive current can be determined, and the compensation signal can be determined according to the pulse number difference, so that the drive voltage generation module 12 generates the target data signal according to the compensation signal to complete the compensation of the data signal.

[0068] In one embodiment, Figure 4 As shown, the processing circuit 113 includes: a counter U8, a subtractor U9 and a lookup table unit U7.

[0069] The first end of the counter U8 is connected to the first end of the sampling circuit 111 and is used to count the pulses of the initial driving current. When a stop signal is received, the counter U8 stops counting to obtain the current clock pulse number.

[0070] The first end of the subtractor U9 is connected to the second end of the counter U8, and is used to perform a subtraction operation on the current clock pulse number and the calibration pulse number corresponding to the target grayscale, and output the target pulse number difference.

[0071] The first end of the lookup table unit U7 is connected to the second end of the subtractor U9, and the second end of the lookup table unit U7 is connected to the first end of the driving voltage generating module 12. The lookup table unit U7 is used to store the compensation reference table and determine the compensation signal by looking up the compensation reference table according to the target pulse number difference.

[0072] It can be understood that the counter U8 is connected to the first end of the sampling circuit 111, and when the sampling circuit 111 receives and stores the initial driving current, the counter U8 will also count the pulses of the initial driving current, and stop counting when the counter U8 receives the stop signal, and determine the recorded number of pulses as the current number of clock pulses. The first end of the subtractor U9 is connected to the second end of the counter U8, and the subtractor U9 can receive the current number of clock pulses output by the counter U8, and perform a difference operation between the current number of clock pulses and the corresponding number of calibrated pulses, and output the target number of pulses difference to the lookup table unit U7. The lookup table unit U7 determines the compensation signal by looking up the pre-stored compensation reference table according to the target number of pulses difference, and outputs the compensation signal to the drive voltage generation module 12, so that the drive voltage generation module 12 generates the target data signal according to the compensation signal in the data writing stage, and completes the compensation of the data signal.

[0073] In one embodiment, Figure 4 As shown, the compensation circuit 10 further includes: a second selection switch U2, a second capacitor Cref and a second discharge switch U4.

[0074] The first end of the second selection switch U2 is used to receive the reference current Iref, and is used to receive the initial driving current output by the pixel circuit 30. The first end of the second capacitor Cref is connected to the second end of the second selection switch U2 and the second output end of the comparison circuit 112, respectively, and the second end of the second capacitor Cref is connected to the common ground. The first end of the second discharge switch U4 is connected to the first end of the second capacitor Cref, and the second end of the second discharge switch U4 is connected to the common ground; wherein, in the compensation stage, the second selection switch U2 is turned on, and the second discharge switch U4 is turned off; in the data writing stage, the second selection switch U2 is turned off.

[0075] In the application, a discharge stage can be set before the compensation stage. In the discharge stage, the second discharge switch U4 is turned on, the first end of the second capacitor Cref is connected to the common ground, and the second capacitor Cref is discharged to the ground. In the compensation stage, the second selection switch U2 is turned on, the second discharge switch U4 is turned off, and the second capacitor Cref receives and stores the reference current Iref. Since the second input end of the comparator U5 is connected to the first end of the second capacitor Cref, the second end of the second capacitor Cref outputs the reference voltage Vref to the second input end of the comparator U5. Specifically, the second capacitor Cref receives and stores the reference current Iref, and the processing circuit 113 counts the clock pulses of the reference current Iref. When the clock pulse of the reference current Iref reaches the reference pulse value corresponding to the current gray scale, the voltage output by the second capacitor Cref is the reference voltage Vref, and the second selection switch U2 is closed at this time. After the second selection switch U2 is closed, the processing circuit 113 counts the initial driving current again, stops counting when receiving the stop signal to obtain the current clock pulse number, and determines the compensation signal according to the pulse number difference between the current clock pulse number and the calibrated pulse number corresponding to the target grayscale.

[0076] In one embodiment, the compensation circuit 10 further includes: a control circuit (not shown).

[0077] The control circuit is used to obtain the working time of the display panel and compensate the reference voltage Vref or the reference clock pulse data according to the working time of the display panel.

[0078] It is understandable that as the working time of the display panel increases, the components of the display panel will age, and the aging of the display panel will cause the display brightness to decay and become uneven. Therefore, in this embodiment, the working time of the display panel is obtained by the control circuit, and the reference voltage Vref or the reference clock pulse data is compensated according to the working time of the display panel, thereby compensating for the display brightness decay and unevenness caused by the aging phenomenon, effectively increasing the service life of the display panel and improving the display quality.

[0079] In the application, the reference clock pulse data can be compensated in the following manner, and multiple groups of pulse number increment values ​​W related to the working time are preset. When aging compensation is required, the corresponding aging increment value W is added to the initial calibrated pulse number according to the working time of the display panel to generate a new pulse number target setting table. For example, the calibrated pulse number corresponding to the pixel in the i-th row and j-th column of the initial calibration table is Pij, and the aging increment value is W at this time. Then the new calibrated pulse number of the pixel is Pij+W, and the calibrated pulse numbers of other pixels are also added with the aging increment W to generate a pulse number target setting table corresponding to the working time. On this basis, the compensation method in the aforementioned embodiment is used to compensate for the display brightness attenuation and unevenness caused by aging.

[0080] Exemplarily, multiple working time intervals can be preset, each working time interval corresponds to a compensation parameter, and the target compensation parameter is determined according to the working time interval in which the display panel is working. The reference voltage Vref or the reference clock pulse data is compensated by the target compensation parameter, thereby adjusting the compensation signal and then adjusting the target data signal.

[0081] In another embodiment, the compensation circuit 10 further includes: a control circuit.

[0082] The control circuit is used to obtain the working time of the display panel, determine the target current information according to the working time of the display panel, and generate a corresponding target current as a new reference current Iref according to the target current information, wherein the target current information includes one of a target current value and a target pulse number.

[0083] In the application, multiple groups of reference current values ​​or multiple groups of fixed pulse numbers can be pre-stored. When aging compensation is required, the target current value or target pulse number is selected from the pre-stored multiple groups of reference current values ​​or multiple groups of fixed pulse numbers according to the working time of the display panel, and the corresponding target current is controlled to be generated as a new reference current Iref according to the target current value or target pulse number, and the reference voltage Vref is increased, and the threshold voltage of the comparison voltage is increased, thereby improving the compensation parameters, and effectively compensating for the display brightness attenuation and unevenness caused by aging.

[0084] In one embodiment, Figure 5 As shown, the present application further provides a display driver chip 100 , comprising the compensation circuit 10 as described in the above embodiment.

[0085] The display driver chip 100 includes a compensation circuit 10. The compensation circuit 10 can generate a compensated target data signal. After the target data signal is output to the pixel circuit 20 to be compensated, the pixel circuit 20 to be compensated can output a new driving current under the target data signal, and then in the light-emitting stage, the new driving current is output to the light-emitting element to drive the light-emitting element to emit light. The new driving current output in the above manner has a high consistency, which can improve the consistency of the driving current driving the light in each pixel, thereby improving the brightness uniformity of the entire display panel to improve the display effect.

[0086] Based on the same inventive concept, Figure 6 As shown, the present application further provides a display panel 200 , which includes a pixel circuit 30 and the compensation circuit 10 as described in the above embodiment, wherein the pixel circuit 30 is connected to the compensation circuit 10 .

[0087] The display panel 200 includes a pixel circuit 30 and a compensation circuit 10 as described in the above embodiment. In the compensation stage, the pixel circuit 30 outputs an initial driving current to the compensation circuit 10. The compensation circuit 10 receives the initial driving current and generates a compensated target data signal based on the initial driving current. In the data writing stage, the compensation circuit 10 outputs the target data signal to the pixel circuit 30, so that the pixel circuit 30 can output a new driving current under the target data signal. Then, in the light-emitting stage, the pixel circuit 30 outputs the new driving current to the light-emitting element to drive the light-emitting element to emit light. The new driving current outputted in the above manner has a high consistency, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel 200 to improve the display effect.

[0088] In one embodiment, Figure 7 and Figure 8 As shown, the pixel circuit 30 includes: a driving transistor T1 , a storage module 31 , a data writing module 32 and a sensing module 33 .

[0089] The first electrode of the driving transistor T1 is used to receive the first power signal ELVDD, and the driving transistor T1 is used to provide a driving current to the light-emitting element. The cathode of the light-emitting element receives the second power signal ELVSS. In the light-emitting stage, the first power signal ELVDD is loaded on the anode of the light-emitting element, and the second power signal ELVSS is loaded on the cathode of the light-emitting element to drive the light-emitting element to emit light.

[0090] A first end of the storage module 31 is connected to a first electrode of the driving transistor T1 , and a second end of the storage module 31 is connected to a gate of the driving transistor T1 .

[0091] The first end of the data writing module 32 is used to receive the data signal, the second end of the data writing module 32 is respectively connected to the first electrode of the driving transistor T1 and the second end of the storage module 31, and the control end of the data writing module 32 is used to receive and respond to the first scanning signal S1, so that the data writing module 32 is turned on in the initialization stage and the data writing stage. The data writing module 32 can be turned on when the first scanning signal S1 is at a low potential, and disconnected when the first scanning signal S1 is at a high potential.

[0092] The first terminal of the sensing module 33 is connected to the second electrode of the driving transistor T1, and the control terminal of the sensing module 33 is used to receive and respond to the second scanning signal S2, so that the sensing module 33 is turned on during the compensation phase to output the initial driving current from the second terminal of the sensing module 33. The sensing module 33 can be turned on when the second scanning signal S2 is at a low potential, and turned off when the second scanning signal S2 is at a high potential.

[0093] The initialization phase is before the compensation phase, which is before the data writing phase. The data writing module 32 is used to receive an uncompensated initial data signal in the initialization phase and to receive a compensated target data signal in the data writing phase.

[0094] It can be understood that in the initialization stage, the driving voltage generating module 12 of the compensation circuit 10 outputs an initial data signal to the first end of the data writing module 32, the data writing module 32 is turned on in response to the first scanning signal S1, and the initial data signal is written to the second end of the storage module 31 and the gate of the driving transistor T1.

[0095] In the compensation stage, the data writing module 32 is disconnected, and the sensing module 33 is turned on in response to the second scanning signal S2. Since the storage module 31 stores the initial data signal in the initialization stage, the initial driving current outputted from the second end of the driving transistor T1 at this time is the actual driving current corresponding to the current grayscale before compensation. After the sensing module 33 is turned on in response to the second scanning signal S2, the initial driving current is outputted to the compensation module 11 of the compensation circuit 10 through the sensing module 33. The compensation module 11 determines the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current.

[0096] In the data writing stage, the driving voltage generating module 12 generates a target data signal according to the compensation signal and outputs it to the first end of the data writing module 32. In this stage, the data writing module 32 is turned on again in response to the first scanning signal S1, and the target data signal is written into the second end of the storage module 31 and the gate of the driving transistor T1 through the data writing module 32, so that the second end of the driving transistor T1 outputs a new driving current, thereby realizing compensation for the driving current, improving the consistency of the driving current, and further improving the brightness uniformity of the display panel 200.

[0097] In one embodiment, Figure 7 As shown, the second end of the sensing module 33 is connected to the first end of the data writing module 32 .

[0098] It can be understood that since the initial driving current is output by the pixel circuit 30 to the compensation module 11 in the compensation stage, and the initial data signal and the target data signal are output by the driving voltage generating module 12 to the pixel circuit 30 in the initialization stage and the data writing stage, respectively, the transmission stages of the initial driving current and the data signal are different. Based on this, the second end of the sensing module 33 is connected to the first end of the data writing module 32, so that the transmission signal line of the initial driving current and the transmission signal line of the data signal (initial data signal and target data signal) can be the same signal line, that is, the data signal line can be multiplexed as a signal line for transmitting the initial driving current, so there is no need to set an additional signal line for transmitting the initial driving current, reducing the number of signal lines, which is conducive to simplifying the routing of the display panel 200.

[0099] In one embodiment, Fig. 9 As shown, the data writing module 32 includes: a data writing transistor T2.

[0100] The first electrode of the data writing transistor T2 is used to receive the data signal, the second electrode of the data writing transistor T2 is respectively connected to the gate of the driving transistor T1 and the second end of the storage module 31, and the gate of the data writing transistor T2 is used to receive the first scanning signal S1.

[0101] Among them, in the initialization stage, the gate of the data writing transistor T2 receives the first scanning signal S1, the data writing transistor T2 is turned on in response to the first scanning signal S1, the first electrode of the data writing transistor T2 receives the initial data signal, and the initial data signal is transmitted to the second end of the storage module 31 and the gate of the driving transistor T1 through the first electrode and the second electrode of the data writing transistor T2, thereby writing the initial data signal into the second end of the storage module 31 and the gate of the driving transistor T1.

[0102] In the data writing stage, the gate of the data writing transistor T2 receives the first scanning signal S1, the data writing transistor T2 is turned on in response to the first scanning signal S1, the first electrode of the data writing transistor T2 receives the target data signal, and the target data signal is transmitted to the second end of the storage module 31 and the gate of the driving transistor T1 through the first electrode and the second electrode of the data writing transistor T2, thereby writing the target data signal into the second end of the storage module 31 and the gate of the driving transistor T1.

[0103] In one embodiment, Fig. 9 As shown, the sensing module 33 includes: a sensing transistor T3.

[0104] The first electrode of the sensing transistor T3 is connected to the second electrode of the driving transistor T1 , and the gate of the sensing transistor T3 is used to receive and respond to the second scanning signal S2 , so that the sensing transistor T3 is turned on in the compensation phase to output an initial driving current from the second electrode of the sensing transistor T3 .

[0105] In which, during the compensation stage, the gate of the sensing transistor T3 receives the second scanning signal S2, the sensing transistor T3 is turned on in response to the second scanning signal S2, and the initial driving current output by the second electrode of the driving transistor T1 is output to the compensation circuit 10 through the first electrode and the second electrode of the sensing transistor T3, so that the compensation circuit 10 can determine the compensation signal based on the initial driving current.

[0106] In one embodiment, Fig. 9 As shown, the pixel circuit 30 further includes: a light emitting control module 34 .

[0107] The first end of the light control module 34 is connected to the second electrode of the driving transistor T1, the second end of the light control module 34 is connected to the anode of the light emitting element, and the control end of the light control module 34 is used to receive and respond to the light control signal EM to turn on the light control module 34 in the light emitting stage.

[0108] Among them, Figure 8 As shown, the light emitting control module 34 can be turned on when the light emitting control signal EM is at a low level, and can be turned off when the light emitting control signal EM is at a high level.

[0109] In the light-emitting stage, the control end of the light-emitting control module 34 receives the light-emitting control signal EM, and the light-emitting control module 34 is turned on in response to the light-emitting control signal EM. Since the first electrode of the driving transistor T1 receives the first power signal ELVDD and the cathode of the light-emitting element receives the second power signal ELVSS, when the light-emitting control module 34 is turned on in response to the light-emitting control signal EM, a new driving current output by the second electrode of the driving transistor T1 is output to the light-emitting element through the first end and the second end of the light-emitting control module 34, driving the light-emitting element to emit light, so that the actual brightness displayed by the light-emitting element reaches the current predetermined display grayscale.

[0110] The light emitting control module 34 may include a light emitting control transistor T4, a first electrode of the light emitting control transistor T4 is connected to a second electrode of the driving transistor T1, a second electrode of the light emitting control transistor T4 is connected to an anode of the light emitting element, and a gate of the light emitting control transistor T4 is used to receive a light emitting control signal EM. In the light emitting stage, the light emitting control transistor T4 is turned on in response to the light emitting control signal EM, so that the driving current is output to the light emitting element, and the light emitting element is driven to emit light.

[0111] In one embodiment, the storage module 31 may include a storage capacitor, a first end of the storage capacitor may be connected to the first electrode of the driving transistor T1 and receive a first power signal ELVDD, and a second end of the storage capacitor may be connected to the second end of the data writing module 32 and the gate of the driving transistor T1, respectively, so that when the data writing module 32 is turned on, the storage capacitor may store the data voltage.

[0112] Based on the above embodiments, Fig.10 As shown, in one embodiment, the compensation circuit 10 includes a first selection switch U1, a first capacitor Cdet, a first discharge switch U3, a second selection switch U2, a second capacitor Cref, a second discharge switch U4, a comparator U5, a logic control unit U6, a counter U8, a subtractor U9, a lookup table unit U7 and a driving voltage generating module 12, and the pixel circuit 30 includes a driving transistor T1, a storage capacitor, a data writing transistor T2, a sensing transistor T3 and a light emitting control transistor T4.

[0113] Among them, the first electrode of the driving transistor T1 is connected to the first end of the storage capacitor and is used to receive the first power supply signal ELVDD, and the second electrode of the driving transistor T1 is connected to the first electrode of the light-emitting control transistor T4 and the first electrode of the sensing transistor T3. The control end of the data writing transistor T2 is used to receive the first scanning signal S1, the first electrode of the data writing transistor T2 is used to receive the data signal, and the second electrode of the data writing transistor T2 is connected to the second end of the storage capacitor and the gate of the driving transistor T1. The gate of the sensing transistor T3 is used to receive the second scanning signal S2, and the second electrode of the sensing transistor T3 is connected to the first electrode of the data writing transistor T2 to output the initial driving current through the data signal line. The gate of the light-emitting control transistor T4 is used to receive the light-emitting control signal EM, and the second electrode of the light-emitting control transistor T4 is connected to the anode of the light-emitting element.

[0114] In the application, in the initialization stage and the data writing stage, the data writing transistor T2 is turned on in response to the first scanning signal S1, and the sensing transistor T3 and the light emitting control transistor T4 are turned off. In the compensation stage, the sensing transistor T3 is turned on in response to the second scanning signal S2, and the data writing transistor T2 and the light emitting control transistor T4 are turned off. The initialization stage is located before the compensation stage, and the compensation stage is located before the data writing stage.

[0115] The first end of the first selection switch U1 is used to connect to the pixel circuit 3020 to be compensated, and is used to receive the initial driving current output by the pixel circuit 30. The first end of the first capacitor Cdet is connected to the second end of the first selection switch U1, and the second end of the first capacitor Cdet is connected to the common ground. The first end of the first discharge switch U3 is connected to the first end of the first capacitor Cdet, and the second end of the first discharge switch U3 is connected to the common ground. In the compensation stage, the first selection switch U1 is turned on and the first discharge switch U3 is turned off; in the data writing stage, the first selection switch U1 is turned off.

[0116] The first end of the second selection switch U2 is used to receive the reference current Iref, and is used to receive the initial driving current output by the pixel circuit 30. The first end of the second capacitor Cref is respectively connected to the second end of the second selection switch U2 and the second output end of the comparison circuit 112, and the second end of the second capacitor Cref is connected to the common ground. The first end of the second discharge switch U4 is connected to the first end of the second capacitor Cref, and the second end of the second discharge switch U4 is connected to the common ground. In the compensation stage, the second selection switch U2 is turned on and the second discharge switch U4 is turned off; in the data writing stage, the second selection switch U2 is turned off.

[0117] The first input terminal of the comparator U5 is connected to the first terminal of the sampling circuit 111, the second input terminal of the comparator U5 is used to receive the reference voltage Vref, the first input terminal of the comparator U5 is used to receive the voltage output by the first terminal of the sampling circuit 111, the comparator U5 is used to output a first logic signal when the voltage of the input signal at the first input terminal of the comparison circuit 112 is greater than the reference voltage Vref, and output a second logic signal when the voltage of the input signal at the first input terminal of the comparison circuit 112 is less than the reference voltage Vref. The logic control unit U6 is connected to the output terminal of the comparator U5, and the logic control unit U6 is used to output a stop signal when receiving the first logic signal.

[0118] The first end of the counter U8 is connected to the first end of the sampling circuit 111, and is used to count the pulses of the initial driving current, and stop counting when receiving a stop signal to obtain the current number of clock pulses. The first end of the subtractor U9 is connected to the second end of the counter U8, and is used to perform a subtraction operation on the current number of clock pulses and the calibrated number of pulses corresponding to the target grayscale, and output the target pulse number difference. The first end of the lookup table unit U7 is connected to the second end of the subtractor U9, and the second end of the lookup table unit U7 is connected to the first end of the driving voltage generating module 12. The lookup table unit U7 is used to store a compensation reference table, and to determine a compensation signal by looking up the compensation reference table according to the target pulse number difference.

[0119] Based on the same inventive concept, the present application also provides a display panel driving method, which is applied to the display panel 200 in the above embodiment. Fig.11 As shown, the driving method of the display panel includes the following steps S1101 to S1104.

[0120] S1101: In the compensation phase, an initial driving current output by the pixel circuit according to an initial data signal in the initialization phase is obtained.

[0121] The initialization phase is before the compensation phase. In the initialization phase, the driving voltage generating module 12 can generate an initial data signal and output it to the pixel circuit 30. The pixel circuit 30 receives and stores the initial data signal and outputs an initial driving current in the compensation phase.

[0122] S1102: Determine a compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current.

[0123] In the compensation stage, the pixel circuit 30 generates an initial driving current based on the stored initial data signal, and outputs the initial driving current to the compensation module 11. It can be understood that the initial driving current is the driving current output by the pixel circuit 30 under the initial data signal (the data signal without compensation processing) to drive the light-emitting element to emit light, and the reference clock pulse data includes the calibrated pulse number corresponding to the target driving current output by the pixel circuit 30 at different grayscales. Based on the reference clock pulse data, the corresponding calibrated pulse number of the currently predetermined display grayscale can be determined, and the current clock pulse number corresponding to the initial driving current is the actual pulse number corresponding to the currently predetermined display grayscale. Based on the calibrated pulse number and the actual pulse number of the currently predetermined display grayscale, the voltage to be compensated can be determined, and then the compensation signal can be determined.

[0124] S1103: Generate a target data signal according to the compensation signal, wherein the reference clock pulse data includes the calibrated pulse number corresponding to the target driving current output by the pixel circuit at different gray scales.

[0125] After determining the compensation signal, the driving voltage generating module 12 may generate a target data signal to achieve compensation for the data signal.

[0126] S1104: In the data writing phase, the target data signal is output to the pixel circuit so that the pixel circuit generates a new driving current.

[0127] Among them, the compensation phase is before the data writing phase.

[0128] It can be understood that, in the compensation stage of the pixel circuit 30, the pixel circuit 30 outputs the initial driving current to the compensation module 11, the compensation module 11 determines the compensation signal according to the initial driving current, and sends the compensation signal to the driving voltage generating module 12, and the driving voltage generating module 12 generates the target data signal according to the compensation signal. In the data writing stage of the pixel circuit 30, the driving voltage generating module 12 outputs the target data signal to the pixel circuit 30, so that the pixel circuit 30 outputs a new driving current under the target data signal, and then in the light emitting stage, the new driving current is output to the light emitting element, driving the light emitting element to emit light, so that the actual brightness of the display reaches the current predetermined display grayscale.

[0129] In the driving method of the display panel 200, in the initialization stage, the driving voltage generating module 12 generates an initial data signal and outputs it to the pixel circuit 30, and the pixel circuit 30 receives and stores the initial data signal; in the compensation stage, the compensation module 11 receives the initial driving current of the pixel circuit 30 in the compensation stage of the pixel circuit 30, determines the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current, and the driving voltage generating module 12 receives the compensation signal and generates the target data signal according to the compensation signal. In the data writing stage of the pixel circuit 30, the driving voltage generating module 12 outputs the target data signal to the pixel circuit 30, so that the pixel circuit 30 outputs a new driving current under the target data signal, and then in the light-emitting stage, the new driving current is output to the light-emitting element to drive the light-emitting element to emit light. The consistency of the new driving current outputted in the above manner is high, which can improve the consistency of the driving current driving the light emission in each pixel, thereby improving the brightness uniformity of the entire display panel 200 to improve the display effect.

[0130] In one embodiment, the pixel circuit includes a driving transistor, a storage module, a data writing module and a sensing module. Fig.12 As shown, the method for driving the display panel further includes the following steps S1201 to S1203.

[0131] S1201: In the initialization phase, the data writing module is turned on in response to the first scanning signal, receives the initial data signal output by the driving voltage generating module, and writes the initial data voltage into the gate of the driving transistor and the second end of the storage module.

[0132] It can be understood that in the initialization stage, the driving voltage generating module 12 of the compensation circuit 10 outputs an initial data signal to the first end of the data writing module 32, the data writing module 32 is turned on in response to the first scanning signal S1, and the initial data signal is written to the second end of the storage module 31 and the gate of the driving transistor T1, thereby realizing the storage of the initial data signal.

[0133] S1202: In the compensation stage, the sensing module is turned on in response to the second scanning signal, and the sensing module outputs an initial driving current to the compensation module.

[0134] In the compensation stage, the data writing module 32 is disconnected, and the sensing module 33 is turned on in response to the second scanning signal S2. Since the storage module 31 stores the initial data signal in the initialization stage, the initial driving current outputted from the second end of the driving transistor T1 at this time is the actual driving current corresponding to the current grayscale before compensation. After the sensing module 33 is turned on in response to the second scanning signal, the initial driving current is outputted to the compensation module 11 of the compensation circuit 10 through the sensing module 33. The compensation module 11 determines the compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current.

[0135] S1203: In the data writing phase, the data writing module is turned on in response to the first scanning signal, so that the target data signal is written into the gate of the driving transistor and the second end of the storage module.

[0136] In the data writing stage, the driving voltage generating module 12 generates a target data signal according to the compensation signal and outputs it to the first end of the data writing module 32. In this stage, the data writing module 32 is turned on again in response to the first scanning signal S1, and the target data signal is written into the second end of the storage module 31 and the gate of the driving transistor T1 through the data writing module 32, so that the second end of the driving transistor T1 outputs a new driving current, thereby realizing compensation for the driving current, improving the consistency of the driving current, and further improving the brightness uniformity of the display panel 200.

[0137] In one embodiment, the pixel circuit further comprises a light emitting control module. The driving method further comprises: in the light emitting stage, the light emitting control module is turned on in response to the light emitting control signal to form a driving current path, and the driving transistor provides a driving current to the light emitting element.

[0138] It can be understood that in the light-emitting stage, the control end of the light-emitting control module 34 receives the light-emitting control signal EM, and the light-emitting control module 34 is turned on in response to the light-emitting control signal EM. Since the first electrode of the driving transistor T1 receives the first power signal ELVDD, and the cathode of the light-emitting element receives the second power signal ELVSS, when the light-emitting control module 34 is turned on in response to the light-emitting control signal, the new driving current output by the second electrode of the driving transistor T1 is output to the light-emitting element through the first end and the second end of the light-emitting control module 34, driving the light-emitting element to emit light, so that the actual brightness displayed by the light-emitting element reaches the current predetermined display grayscale.

[0139] In one embodiment, the driving method further includes: in the compensation stage, performing a subtraction operation on the current clock pulse number and the calibrated pulse number corresponding to the target grayscale to obtain the target pulse number difference, and determining the compensation signal by looking up the compensation reference table according to the target pulse number difference.

[0140] It can be understood that the calibrated pulse number and the current clock pulse number are determined in the same way. The difference is that the calibrated pulse number corresponds to the target driving current under the target grayscale, and the current clock pulse number corresponds to the initial driving current. The difference between the target driving current and the initial driving current can be determined based on the pulse number difference between the calibrated pulse number and the current clock pulse number. The compensation signal can be determined based on the pulse number difference, so that the driving voltage generating module 12 generates the target data signal according to the compensation signal to complete the compensation of the data signal.

[0141] In one embodiment, the driving method also includes: in the compensation stage, outputting the target data signal to the pixel circuit; receiving the new initial driving current output by the pixel circuit according to the target data signal, and obtaining the current clock pulse number corresponding to the new initial driving current; obtaining the pulse number difference between the current clock pulse number and the calibrated pulse number corresponding to the target grayscale; when the pulse number difference does not meet the preset conditions, using the pulse number difference as the target pulse number difference; when the pulse number difference meets the preset conditions, entering the data writing stage.

[0142] The preset condition may be that the pulse number difference is less than a preset threshold, or may be that the pulse number difference is 0.

[0143] It can be understood that in the compensation stage, the driving voltage generation module 12 outputs the target data signal to the pixel circuit 30, and the pixel circuit 30 receives the target data signal and outputs a new initial driving current. By obtaining the pulse number difference between the current clock pulse number corresponding to the new initial driving current and the calibrated pulse number corresponding to the target grayscale, the smaller the pulse number difference is, the closer the new initial driving current is to the target driving current, and the better the compensation effect is. Therefore, if the pulse number difference does not meet the preset conditions, it means that the compensation effect is poor, then the pulse number difference is used as the target pulse number difference, and the compensation signal is generated again according to the target pulse number difference. The driving voltage generation module 12 generates a new target data signal according to the compensation signal, and then repeats the above process until the pulse number difference meets the preset conditions. When the pulse number difference meets the preset conditions, the driving voltage generation module 12 generates the final target data signal according to the compensation signal finally received, and outputs it to the pixel circuit 30 in the data writing stage.

[0144] In one embodiment, the driving method further comprises: in the compensation phase, a step of updating a pre-stored grayscale data table according to the compensation signal, wherein the grayscale data table is a correlation table between grayscale and data signal.

[0145] In the application, according to the actual situation of the light-emitting current drift change of the display panel 200, certain specific pixel units can be selected or the above-mentioned compensation operation can be performed one by one on the pixel units of the entire panel, and the corresponding compensation signal can be obtained. The pre-stored grayscale data table is updated according to the compensation signal, so that there is no need to perform compensation operations in subsequent use, and the target data signal information can be determined directly according to the grayscale data table.

[0146] In one embodiment, the display panel includes a sampling circuit, a comparison circuit and a processing circuit. The driving method also includes the steps of obtaining the working time of the display panel and compensating the reference voltage or reference clock pulse data according to the working time of the display panel.

[0147] It is understandable that as the working time of the display panel 200 increases, the components of the display panel 200 will age, and the aging of the display panel 200 will cause display brightness attenuation and unevenness. Therefore, in this embodiment, the working time of the display panel 200 is obtained by the control circuit, and the reference voltage or reference clock pulse data is compensated according to the working time of the display panel 200, so as to compensate for the display brightness attenuation and unevenness caused by the aging phenomenon, effectively increase the service life of the display panel 200, and improve the display quality.

[0148] It should be understood that, although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the accompanying drawings may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a portion of the steps or stages in other steps.

[0149] Based on the same inventive concept, an embodiment of the present application further provides a display device (not shown), which includes the display panel in the above embodiment.

[0150] It can be understood that the display device in the embodiments of the present application can be an OLED display device, a QLED display device, electronic paper, a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, a wearable device, an Internet of Things device, or any other product or component with a display function, and the embodiments disclosed in the present application are not limited to this.

[0151] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0152] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0153] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A compensation circuit, characterized in that: include: A compensation module, wherein a first end of the compensation module is used to connect to a pixel circuit to be compensated, the compensation circuit is used to receive an initial driving current output by the pixel circuit to be compensated, and determine a compensation signal according to reference clock pulse data and a current clock pulse number corresponding to the initial driving current, wherein the reference clock pulse data includes a calibrated pulse number corresponding to a target driving current output by the pixel circuit to be compensated at different grayscales; a driving voltage generating module, wherein a first end of the driving voltage generating module is connected to a second end of the compensation module, and a second end of the driving voltage generating module is connected to the pixel circuit to be compensated, and the driving voltage generating module is used to generate a target data signal according to the compensation signal during a compensation phase of the pixel circuit to be compensated, and output the target data signal to the pixel circuit to be compensated during a data writing phase of the pixel circuit to be compensated; wherein the compensation phase is before the data writing phase; The compensation circuit comprises: a sampling circuit, wherein a first terminal of the sampling circuit is connected to the pixel circuit to be compensated, a second terminal of the sampling circuit is connected to a common ground terminal, and the sampling circuit is used to receive and store an initial driving current output by the pixel circuit to be compensated; A comparison circuit, wherein a first input terminal of the comparison circuit is connected to a first terminal of the sampling circuit, a second input terminal of the comparison circuit is used to receive a reference voltage, and the comparison circuit is used to output a stop signal when a voltage input to the first input terminal is greater than the reference voltage; a processing circuit, wherein a first input terminal of the processing circuit is connected to a first terminal of the sampling circuit, a second input terminal of the processing circuit is connected to an output terminal of the comparison circuit, the processing circuit is used to count pulses of the initial driving current, stop counting upon receiving the stop signal to obtain the current clock pulse number, and determine the compensation signal according to a pulse number difference between the current clock pulse number and a calibrated pulse number corresponding to a target grayscale; The processing circuit comprises: a counter, wherein a first end of the counter is connected to a first end of the sampling circuit, and is used to count pulses of the initial driving current, and stops counting when receiving the stop signal to obtain the current clock pulse number; A subtractor, wherein a first end of the subtractor is connected to a second end of the counter, and is used to perform a subtraction operation on the current clock pulse number and the calibration pulse number corresponding to the target grayscale, and output a target pulse number difference; A lookup table unit, wherein the first end of the lookup table unit is connected to the second end of the subtractor, the second end of the lookup table unit is connected to the first end of the drive voltage generating module, the lookup table unit is used to store a compensation reference table, and to determine the compensation signal by looking up the compensation reference table according to the target pulse number difference.

2. The compensation circuit according to claim 1, characterized in that: The second end of the driving voltage generating module is also connected to the first end of the compensation module.

3. The compensation circuit according to claim 1, characterized in that: The sampling circuit comprises: a first selection switch, wherein a first end of the first selection switch is used to be connected to the pixel circuit to be compensated, and is used to receive an initial driving current output by the pixel circuit to be compensated; a first capacitor, wherein a first end of the first capacitor is connected to a second end of the first selection switch, and a second end of the first capacitor is connected to the common ground; A first discharge switch, wherein a first end of the first discharge switch is connected to a first end of the first capacitor, and a second end of the first discharge switch is connected to the common ground; wherein In the compensation phase, the first selection switch is turned on and the first discharge switch is turned off; in the data writing phase, the first selection switch is turned off.

4. The compensation circuit according to claim 1, characterized in that: The comparison circuit comprises: A comparator, wherein a first input terminal of the comparator is connected to a first terminal of the sampling circuit, a second input terminal of the comparator is used to receive the reference voltage, a first input terminal of the comparator is used to receive a voltage output by the first terminal of the sampling circuit, and the comparator is used to output a first logic signal when a voltage of a signal input to the first input terminal of the comparison circuit is greater than the reference voltage, and output a second logic signal when a voltage of a signal input to the first input terminal of the comparison circuit is less than the reference voltage; A logic control unit is connected to the output end of the comparator, and is used for outputting the stop signal when receiving the first logic signal.

5. The compensation circuit according to claim 1, characterized in that: The compensation circuit further includes: a second selection switch, wherein a first end of the second selection switch is used to receive a reference current, and is used to receive an initial driving current output by the pixel circuit to be compensated; a second capacitor, wherein a first end of the second capacitor is respectively connected to the second end of the second selection switch and the second output end of the comparison circuit, and a second end of the second capacitor is connected to the common ground end; a second discharge switch, wherein a first end of the second discharge switch is connected to a first end of the second capacitor, and a second end of the second discharge switch is connected to the common ground; In the compensation phase, the second selection switch is turned on and the second discharge switch is turned off; in the data writing phase, the second selection switch is turned off.

6. The compensation circuit according to claim 1, characterized in that: The compensation circuit further includes: A control circuit is used to obtain the working time of the display panel and compensate the reference voltage or the reference clock pulse data according to the working time of the display panel.

7. The compensation circuit according to claim 1, characterized in that: The compensation circuit further includes: A control circuit, wherein the control circuit is used to obtain the working time of the display panel, determine the target current information according to the working time of the display panel, and generate a corresponding target current as a new reference current according to the target current information, wherein the target current information includes one of a target current value and a target pulse number.

8. A display driver chip, characterized in that: Comprising the compensation circuit as claimed in any one of claims 1 to 7.

9. A display panel, characterized in that: The display panel comprises a pixel circuit and a compensation circuit as claimed in any one of claims 1 to 7, wherein the pixel circuit is connected to the compensation circuit.

10. The display panel according to claim 9, characterized in that: The pixel circuit comprises: A driving transistor, wherein a first electrode of the driving transistor is used to receive a first power supply signal, and the driving transistor is used to provide a driving current to the light emitting element; A storage module, wherein a first end of the storage module is connected to a first electrode of the driving transistor, and a second end of the storage module is connected to a gate electrode of the driving transistor; A data writing module, wherein a first end of the data writing module is used to receive a data signal, a second end of the data writing module is respectively connected to a first electrode of the driving transistor and a second end of the storage module, and a control end of the data writing module is used to receive and respond to a first scanning signal so that the data writing module is turned on in an initialization phase and a data writing phase respectively; a sensing module, wherein a first terminal of the sensing module is connected to a second electrode of the driving transistor, and a control terminal of the sensing module is used to receive and respond to a second scanning signal so that the sensing module is turned on during a compensation phase to output an initial driving current from the second terminal of the sensing module; The initialization phase is located before the compensation phase, which is located before the data writing phase. The data writing module is used to receive an uncompensated initial data signal in the initialization phase and to receive a compensated target data signal in the data writing phase.

11. The display panel according to claim 10, characterized in that: The second end of the sensing module is connected to the first end of the data writing module.

12. The display panel according to claim 10, characterized in that: The data writing module comprises: A data writing transistor, wherein the first electrode of the data writing transistor is used to receive the data signal, the second electrode of the data writing transistor is respectively connected to the gate of the driving transistor and the second end of the storage module, and the gate of the data writing transistor is used to receive the first scanning signal.

13. The display panel according to claim 10, characterized in that: The sensing module comprises: A sensing transistor, wherein a first electrode of the sensing transistor is connected to a second electrode of the driving transistor, and a gate of the sensing transistor is used to receive and respond to a second scanning signal so that the sensing transistor is turned on during a compensation phase to output the initial driving current from the second electrode of the sensing transistor.

14. The display panel according to any one of claims 10 to 13, characterized in that: The pixel circuit further includes: A light-emitting control module, wherein a first end of the light-emitting control module is connected to the second electrode of the driving transistor, a second end of the light-emitting control module is connected to the anode of the light-emitting element, and a control end of the light-emitting control module is used to receive and respond to a light-emitting control signal so that the light-emitting control module is turned on in the light-emitting stage.

15. A method for driving a display panel, applied to the display panel according to any one of claims 9 to 14, characterized in that: The driving method of the display panel includes: In the compensation phase, an initial driving current output by the pixel circuit according to an initial data signal in the initialization phase is obtained; Determine a compensation signal according to the reference clock pulse data and the current clock pulse number corresponding to the initial driving current; Generate a target data signal according to the compensation signal, wherein the reference clock pulse data includes the calibration pulse number corresponding to the target driving current output by the pixel circuit at different gray scales; In the data writing phase, the target data signal is output to the pixel circuit so that the pixel circuit generates a new driving current.

16. The method for driving a display panel according to claim 15, characterized in that: The pixel circuit includes a driving transistor, a storage module, a data writing module and a sensing module; The display panel driving method further includes: In the initialization stage, the data writing module is turned on in response to the first scanning signal, receives the initial data signal output by the driving voltage generating module, and writes the initial data voltage into the gate of the driving transistor and the second end of the storage module; In the compensation stage, the sensing module is turned on in response to the second scanning signal, and the sensing module outputs the initial driving current to the compensation module; In the data writing phase, the data writing module is turned on in response to the first scanning signal, so that the target data signal is written into the gate of the driving transistor and the second end of the storage module.

17. The method for driving a display panel according to claim 15, wherein: The driving method further includes: In the compensation stage, a subtraction operation is performed on the current clock pulse number and the calibration pulse number corresponding to the target grayscale to obtain a target pulse number difference; The compensation signal is determined by looking up a compensation reference table according to the target pulse number difference.

18. The method for driving a display panel according to claim 17, wherein: The driving method further includes: In the compensation stage, outputting the target data signal to the pixel circuit; receiving a new initial driving current output by the pixel circuit according to the target data signal, and acquiring a current clock pulse number corresponding to the new initial driving current; Obtaining a pulse number difference between the current clock pulse number and a calibrated pulse number corresponding to a target grayscale; When the pulse number difference does not meet the preset condition, the pulse number difference is used as the target pulse number difference; When the pulse number difference satisfies a preset condition, the data writing phase is entered.

19. The method for driving a display panel according to any one of claims 15 to 18, characterized in that: The driving method further includes: In the compensation stage, a pre-stored grayscale data table is updated according to the compensation signal, wherein the grayscale data table is a correlation relationship table between grayscale and data signal.

20. The method for driving a display panel according to claim 15, wherein: The display panel includes a sampling circuit, a comparison circuit and a processing circuit; The driving method further includes: The working time of the display panel is obtained, and the reference voltage or the reference clock pulse data is compensated according to the working time of the display panel.

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