Pixel driving circuit, display panel and control method thereof

Abstract

The present application discloses a pixel driving circuit, a display panel, and a method for controlling the same. The pixel driving circuit comprises: a signal generating module (10) configured such that an input terminal is connected to a scan line (L1) and a second scan signal is generated according to a first scan signal and output to a first output terminal; and a light-emitting driving module (20) in which a first control terminal, a second control terminal, and a third control terminal are connected to correspond to the scan line (L1), a data line (L2), and the first output terminal of the signal generating module (10).

Description

Technology Field

[0001] This application claims priority to Chinese patent application No. 202210929800.6 filed on August 4, 2022, and all contents of said Chinese patent application are incorporated by reference into this application.

[0002] This application relates to the field of display technology, and in particular to a pixel driving circuit, a display panel, and a method for controlling the same. Background Technology

[0003] Currently, self-emissive display panels, such as Organic Light-emitting Diode (OLED) panels, are widely used in electronic products such as mobile phones and laptops due to their various advantages, such as relatively high contrast. However, the driving circuit of the light-emitting module in conventional self-emissive panels must connect multiple scan signals and is subject to various influences such as driving algorithms, wiring processes, and thin-film transistor processes. Consequently, there are cases where the thin-film transistor in the light-emitting driving circuit fails to turn off at that time, which affects the light emission brightness of the light-emitting element and the display effect of the display panel. The problem to be solved

[0004] The primary objective of this application is to provide a pixel driving circuit. means of solving the problem

[0005] To realize the above-mentioned purpose, the pixel driving circuit submitted in this application is applied to a display panel, said display panel includes a data line, a scan line, and a light-emitting module, said scan line is configured to connect and transmit a first scan signal, and a source line is configured to connect and transmit a data signal, and said pixel driving circuit,

[0006] A signal generation module configured such that an input terminal is connected to the scan line and generates a second scan signal according to the first scan signal and outputs it to a first output terminal; and

[0007] A light-emitting driving module comprising: a first control unit, a second control unit, and a third control unit each being connected to correspond to the scan line, the data line, and the first output unit of the signal generation module, wherein the input unit is configured to be connected to a power supply voltage and the output unit is connected to the light-emitting module;

[0008] The light-emitting driving module is configured to drive the light emission of the light-emitting module by writing the power voltage to the light-emitting module according to the received first scan signal, the second scan signal, and the data signal.

[0009] The present application further provides a method for controlling a display panel, said method for controlling a display panel, said method,

[0010] After confirming that the pixel driving circuit has entered the operation phase, a first scan signal at the first level, a second scan signal at the second level, and a third scan signal at the first level are output to control the pixel driving circuit and enter the initial energy storage phase;

[0011] A step of switching to and outputting a first scan signal at a second level when the first signal edge of a first pulse signal is first detected, switching to and outputting a second scan signal at a first level when the second signal edge of the first pulse signal is first detected, and switching to and outputting a third scan signal at a second level when the first signal edge or the second signal edge of the second pulse signal is first detected, thereby controlling the pixel driving circuit to enter a discharge step;

[0012] A step of switching to and outputting a first scan signal at a first level when the first signal edge of the first pulse signal is detected again, and switching to and outputting a second scan signal at a second level when the second signal edge of the first pulse signal is detected again, thereby controlling the pixel driving circuit to enter a discharge stage;

[0013] The method includes the step of switching to and outputting a first scan signal at a second level when the first signal edge of the first pulse signal is detected for the third time, and switching to and outputting a second scan signal at a first level when the second signal edge of the first pulse signal is detected for the third time, thereby controlling the pixel driving circuit to enter a light emission driving stage;

[0014] One of the first signal edge and the second signal edge is a rising edge, and the other is a falling edge.

[0015] The present application further submits a display panel, said display panel, said display panel,

[0016] Light-emitting module;

[0017] A data line configured to connect and transmit a first scan signal;

[0018] A scan line configured to connect and transmit data signals; and,

[0019] It includes a pixel driving circuit as described above, each connected to the light-emitting module, the data line, and the scan line.

[0020] The present application further provides a display panel, said display panel configured to realize a control method of a display panel as described above, and said display panel,

[0021] Light-emitting module;

[0022] A pixel driving circuit connected to the above-mentioned light-emitting module; and,

[0023] A timing control device configured to be connected to four control terminals of the pixel driving circuit and to output a first scan signal, a second scan signal, a third scan signal, and a data signal to the pixel driving circuit to control the pixel driving circuit and drive the light emission of the light-emitting module. Effects of the invention

[0024] The technical solution of the present application employs a signal generation module and a light-emitting driving module, and processes a first scan signal into a second scan signal required for a light-emitting driving circuit by utilizing the turn-on / turn-off of a switch element with the signal generation module. Since the turn-on / turn-off of the switch element can effectively shorten the rising edge time and the falling edge time, the rising edge time and the falling edge time of the second scan signal become relatively shorter compared to the first scan signal. Consequently, not only is the probability of an overlapping portion occurring between the rising edge time and the falling edge time of the first scan signal and the second scan signal reduced, but the probability of such overlapping portion affecting the light-emitting effect of the pixel unit is also reduced. This solves the problem where a thin-film transistor in the light-emitting driving circuit fails to turn off in time and affects the display effect of the display panel, thereby making it advantageous for improving the display effect and display stability of self-emissive panels such as OLED panels. Next, since the signal generation module is installed in the pixel driving circuit, that is, located in each pixel unit, it effectively avoids the occurrence of subsequent distortion of the second scan signal during the transmission process of the scan line compared to being installed in the gate driving device, and is advantageous for ensuring that the second scan signal, which has a relatively short rising / falling edge time output from the signal generation module, is connected to the light-emitting driving module among each pixel unit. In addition, since one channel of scan signal must proceed through one scan line, the number of scan lines in existing self-emissive panels is at least 2N, where N is the number of rows of the pixel array, and if the technical solution of the present application is adopted, the operation of a self-emissive panel of the same resolution can be driven with N scan lines. In other words, the technical solution of the present application reduces the overall occupied area of ​​the scan line in the display panel, which can be advantageous for high-resolution design of self-emissive panels. Brief explanation of the drawing

[0025] In order to more clearly explain the technical methods among the embodiments of the present application, we will provide a brief introduction to the attached drawings that are to be used in the description of the embodiments below. The drawings in the description below are merely some embodiments of the present application, and it will be obvious to those skilled in the art that other drawings can be obtained according to the structure shown in these drawings without any inventive labor. FIG. 1 is a schematic diagram of a module of a pixel driving circuit of an embodiment of the present application; FIG. 2 is a schematic diagram of another module of the pixel driving circuit of an embodiment of the present application; FIG. 3 is a schematic circuit diagram of a light-emitting driving module in a pixel driving circuit of an embodiment of the present application; FIG. 4 is a schematic circuit diagram of a signal generation circuit among the pixel driving circuits of an embodiment of the present application; FIG. 5 is a schematic diagram of another circuit of a signal generation circuit among the pixel driving circuits of an embodiment of the present application; FIG. 6 is a schematic diagram of the waveform of each scan signal connected to a conventional pixel driving circuit; FIG. 7 is a flowchart of a control method for a display panel of Example 2 of the present application; FIG. 8 is a schematic diagram of the waveform of a relevant signal of the control method of a display panel of Example 2 of the present application; FIG. 9 is a schematic diagram of a module of a display panel of Example 3 of the present application; FIG. 10 is a schematic diagram of the module of the display panel of Example 4 of the present application. The realization, functional features, and advantages of the purpose of this application will be further explained with reference to the attached drawings and in conjunction with embodiments. Specific details for implementing the invention

[0026] Below, we will provide a clear and complete description of the technical solutions in the embodiments of this application in conjunction with the attached drawings. The described embodiments are merely a part of the embodiments of this application, not the whole. Based on the embodiments in this application, all other embodiments obtained by a person skilled in the art without inventive labor fall within the scope of protection of this application.

[0027] Furthermore, descriptions related to "first," "second," etc. in this application are used solely for illustrative purposes and should not be understood as indicating or implying their relative importance, or implicitly indicating the quantity of the technical features described. Accordingly, the features defined by "first" and "second" may explicitly or implicitly include one of the corresponding features. Additionally, technical solutions between each embodiment may be combined, but must be based on what can be realized by a person skilled in the art. If there is a mutual contradiction in the combination of technical solutions or if such combination cannot be realized, it must be acknowledged that such combination of technical solutions does not exist and is not included within the scope of protection claimed in this application.

[0028] Example 1:

[0029] The present application provides a pixel driving circuit, said pixel driving circuit can be applied to a self-emissive display panel such as an OLED panel.

[0030] A display panel may include a plurality of scan lines (L1) and a plurality of data lines (L2), wherein the plurality of scan lines (L1) and the plurality of data lines (L2) are staggered to define a pixel array having a plurality of pixel units, and each scan line (L1) is configured to connect and transmit a single channel scan signal output from a gate driving device to control the turn-on or turn-off of each pixel unit on the corresponding row; and each data line (L2) is configured to connect and transmit a single channel data signal output from a source driving device so that the turned-on pixel unit on the corresponding column can write the data signal. Each pixel unit may be equipped with a light-emitting module and a pixel driving circuit electrically connected to each other, and the light-emitting module may include at least one light-emitting diode light-emitting element, and the pixel driving circuit is configured to drive the light emission of the connected light-emitting module.

[0031] Referring to FIG. 1, in Example 1, the pixel driving circuit is,

[0032] A signal generation module (10) configured such that an input terminal is connected to a scan line (L1) and generates a second scan signal according to a first scan signal and outputs it to a first output terminal; and

[0033] The first control unit, the second control unit, and the third control unit are each connected to correspond to the scan line (L1), the data line (L2), and the first output terminal of the signal generation module (10), and the input terminal is configured to be connected to the power supply voltage (VDD), and the output terminal is connected to the light-emitting module (30); the light-emitting driving module (20) is included;

[0034] The light-emitting driving module (20) is configured to drive the light emission of the light-emitting module (30) by writing a power voltage (VDD) to the light-emitting module (30) according to the received first scan signal, second scan signal, and data signal.

[0035] In the present embodiment, the signal generation module (10) can be constructed by employing a switch element; wherein the switch element may be a MOS tube, a thin-film transistor, a triode, etc., and is not limited thereto. The input terminal of the signal generation module (10) is connected to a scan line (L1) corresponding to a located pixel unit and is installed so that a scan signal transmitted on the scan line (L1), i.e., a first scan signal, is connected. The first scan signal may have two levels, a high level and a low level, and the signal generation module (10) can control the turn-on / turn-off of a corresponding switch element within itself according to the level of the first scan signal to perform signal processing such as level inversion, level delay, and level selection on the connected first scan signal, and can output the first scan signal after signal processing as a second scan signal to the first output terminal.

[0036] The light-emitting driving module (20) can be constructed by employing a plurality of thin-film transistors and an energy storage device. The first control terminal and the second control terminal of the signal generation module (10) are connected to a scan line (L1) and a data line (L2) corresponding to a located pixel unit, so that the first scan signal and the data signal are connected; the third control terminal is connected to the first output terminal of the signal generation module (10) among the located pixel units so that the second scan signal is connected; and the input terminal can be connected to a power management circuit. The second scan signal can likewise have two levels, a high level and a low level, and the light-emitting driving module (20) controls the turn-on or turn-off corresponding to each TTF within itself according to the voltage level where the first scan signal and the second scan signal are present, so that the data signal is connected to the corresponding turned-on thin-film transistor and charging for the energy storage device can proceed. The light-emitting driving module (20) may realize driving the light emission of the light-emitting module (30) by causing a thin-film transistor, which is turned on in accordance with the voltage level having a first scan signal and a second scan signal after the energy storage element is charged, to form a discharge circuit of the energy storage element, and by using the discharge voltage of the energy storage element to trigger the turn-on of the corresponding thin-film transistor, and by connecting the input terminal and the output terminal of the light-emitting driving module (20) so that the power supply voltage (VDD) is written to the light-emitting module (30).

[0037] It can be understood that each scan signal connected to the light-emitting driving module (20) in the existing technical method is output by the gate driving device under the control of the timing control device (40), and is transmitted by each different scan line (L1). In the actual product, due to the influence of the driving algorithm in the timing control device (40) and the hardware error of the gate driving device, there is a certain time between the rising edge (rising waveform rising from a low level to a high level) and the falling edge (falling waveform falling from a high level to a low level) of each scan signal output from the gate driving device, that is, there is a rising edge time and a falling edge time, and each scan line (L1) is additionally affected by the process element, so each scan line (L1) causes a certain signal distortion in the scan signal transmitted during the transmission process, causing different delays in the rising edge time and falling edge time of each scan signal, and an overlapping portion occurs between the rising edge time and falling edge time of different scan signals. For a thin-film transistor, for example, for an N-type thin-film transistor, the thin-film transistor is turned on only when the gate voltage value rises and reaches a threshold voltage, and is turned off only when the gate voltage value falls and becomes lower than the threshold voltage. Thus, if there is an overlap between the rising edge time and the falling delay time of each connected scan signal, two thin-film transistors that should not be turned on simultaneously end up in a turned-on state simultaneously, causing the current circuit within the light-emitting driving circuit to become disordered, which affects the process of writing the power residual voltage (VDD) and the final light-emitting effect of the light-emitting module (30).

[0038] The technical solution of the present application employs a signal generation module (10) and a light-emitting driving module (20), and processes a first scan signal into a second scan signal required for a light-emitting driving circuit by using the turn-on / turn-off of a switch element with the signal generation module (10). Since the turn-on / turn-off of the switch element can effectively shorten the rising edge time and the falling edge time, the rising edge time and the falling edge time of the second scan signal become relatively shorter compared to the first scan signal. This reduces the probability of an overlapping portion occurring between the rising edge time and the falling edge time of the first scan signal and the second scan signal, and also reduces the probability that the overlapping portion affects the light-emitting effect of the pixel unit. This solves the problem where a thin-film transistor in the light-emitting driving circuit is not turned off in time and affects the display effect of the display panel, thereby making it advantageous to improve the display effect and display stability of a self-emissive panel such as an OLED panel. Next, since the signal generation module (10) is installed in the pixel driving circuit, that is, located in each pixel unit, compared to being installed in the gate driving device, it effectively avoids the occurrence of subsequent distortion of the second scan signal during the transmission process of the scan line (L1), and thus can be advantageous in ensuring that the second scan signal, which has a relatively short rising / falling edge time output from the signal generation module (10), is connected to the light-emitting driving module (20) among each pixel unit. In addition, since one channel of scan signals must proceed to transmission through one scan line (L1), the number of scan lines (L1) in the existing self-emissive panel is at least 2N, where N is the number of rows of the pixel array, and if the technical solution of the present application is adopted, the operation of a self-emissive panel of the same resolution can be driven if there are N scan lines (L1). In other words, the technical solution of the present application reduces the overall occupied area of ​​the scan line (L1) in the display panel, which can be advantageous for high-resolution design of the self-emissive panel.

[0039] Referring to FIGS. 2 and 3, in Example 1, the signal generation module (10) is further configured to generate a third scan signal according to a first scan signal and output it to a fourth control unit of a light-emitting driving module (20) at a second output unit;

[0040] The light-emitting driving module (20) is,

[0041] The control unit and input unit are data entry modules (21) that are connected to correspond to the first control unit and second control unit of the light-emitting driving module (20);

[0042] A charge / discharge control module (22) in which the first and second control units are connected to correspond to the third and fourth control units of the light-emitting driving module (20), and the input unit is connected to the output unit of the data writing module (21);

[0043] An energy storage module (23) connected between the output terminal of the data writing module (21) and the input terminal of the charge / discharge control module (22); and

[0044] The control unit is connected to the output unit of the charge / discharge control module (22), and the input unit and output unit are connected to the input unit and output unit of the light-emitting driving module (20) in correspondence with each other, and the driving module (24) is included.

[0045] In the present embodiment, the signal generation module (10) may include two signal generation sub-modules, and the input terminals of the two signal generation sub-modules are each connected to a scan line (L1) corresponding to a pixel unit located therein, so that a first scan signal is connected to each, and the two signal generation sub-modules are each configured to control the turn-on / turn-off of a corresponding switch element within themselves according to the level of the first scan signal, perform corresponding signal processing on the connected first scan signal, and output each of the signal-processed first scan signals as a second scan signal and a third scan signal.

[0046] The light-emitting driving module (20) is configured to drive the light-emitting module (30) by writing a power voltage (VDD) to the light-emitting module (30) according to the received first scan signal, second scan signal, third scan signal, and data signal. The data writing module (21) can be turned on when the first scan signal at one level is received and turned off when the first scan signal at another level is received, and when turned on, the data signal is connected and output to the energy storage module (23) so that charging can proceed for the energy storage module (23). The charge / discharge control module (22) can be turned on when the second scan signal and the third scan signal at corresponding levels are each received and turned off when the second scan signal and the third scan signal at another level are each received, and when turned on, the energy storage module (23) can discharge the discharge voltage to the control unit of the driving module (24). The driving module (24) can be turned on when the voltage value of the control unit voltage reaches a threshold voltage and turned off when the voltage value of the control unit voltage is less than the threshold voltage, and when turned on, it can output a power voltage (VDD) to the light-emitting module (30) to drive the light-emitting module (30).

[0047] Referring to FIGS. 3 and 6, the charge / discharge control module (22) and the data writing module (21) cannot be turned on simultaneously, and the data writing module (21) is turned on only when both the second scan signal and the third scan signal are at corresponding levels, and the data writing module (21) is turned off only when both the second scan signal and the third scan signal are at different levels. Therefore, it can be understood that the requirements for the rising edge time and falling edge time of the first scan signal, the second scan signal, and the third scan signal are more stringent. However, by adopting the technical solution of the present application, the rising edge time and falling edge time of the third scan signal are relatively shorter than those of the first scan signal, so the probability of an overlap occurring between at least two rising edge times and falling edge times among the first scan signal, the second scan signal, and the third scan signal is reduced, which is advantageous for further improving the display effect and display stability of a self-emissive panel such as an OLED panel. Of course, the light-emitting driving module (20) may be further configured to have three or more scan signals connected, and the signal generation module (10) may have a scan signal of one of the channels connected, and generate scan signals of each of the remaining channels connected to the light-emitting driving module (20) according to the scan signal of the connected channel, and a redundant explanation regarding this is omitted.

[0048] Furthermore, the charge / discharge control module (22) is,

[0049] A first switch module (22A) in which the control unit, input unit, and output unit are each connected to correspond to the first control unit, input unit, and output unit of the charge / discharge control module (22);

[0050] A second switch module (22B) in which the control terminal is connected to the second control terminal of the charge / discharge control module (22) and the input terminal is connected to the output terminal of the first switch module (22A); and,

[0051] It includes a third switch module (22C) in which the control terminal is connected to the input terminal of the first switch module (22A), the input terminal is connected to the output terminal of the second switch module (22B), and the output terminal is grounded.

[0052] In this embodiment, the charge / discharge control module (22) may have a 5T1C circuit structure. The data writing module (21) may include a first thin-film transistor (Q1), the first switch module (22A) may include a second thin-film transistor (Q2), the second switch module (22B) may include a third thin-film transistor (Q3), the third switch module (22C) may include a fourth thin-film transistor (Q4), the driving module (24) may include a fifth thin-film transistor (Q5), and the energy storage module (23) may include a first capacitor (C1); wherein one end of the first capacitor (C1) is connected to a path between the data writing module (21) and the charge / discharge control module (22), and the other end is grounded.

[0053] In a specific embodiment, the working steps of the light-emitting driving module (20) include an initial energy storage step (T1), a discharge step (T2), a secondary energy storage step (T3), and a light-emitting driving step (T4) that are executed sequentially;

[0054] In the initial energy storage stage (T1), the data writing module (21) is turned on, and the charge / discharge control module (22) is turned off;

[0055] In the discharge step (T2), the data writing module (21) is turned off, the charge / discharge control module (22) is turned on, and the driving module (24) is turned off;

[0056] In the secondary energy storage stage (T3), the data writing module (21) is turned on, and the charge / discharge control module (22) is turned off;

[0057] In the light-emitting driving step (T4), the data writing module (21) is turned off, and the charge / discharge control module (22) and the driving module (24) are turned on.

[0058] In the embodiment illustrated in FIG. 3, the first thin-film transistor (Q1) to the fifth thin-film transistor (Q5) are all N-type thin-film transistors, and here, using the embodiment illustrated in FIG. 3 as an example, the light-emitting driving module (20) of the present application proceeds with a detailed analysis of the specific work process in the work stage.

[0059] When the data writing module (21) first receives a high-level first scan signal during the operation phase, the light-emitting driving module (20) enters the first energy storage phase (T1). In this phase, the first thin-film transistor (Q1) is turned on, and the data writing module (21) is turned on to output a high-level data signal to the first capacitor (C1), so that the terminal voltage of the first capacitor (C1) can be charged to V. The second scan signal is low level, and the second thin-film transistor (Q2) is turned off, disconnecting the gates of the first capacitor (C1) and the fifth thin-film transistor (Q5); the third scan signal is high level, and the third thin-film transistor (Q3) and the fifth thin-film transistor (Q5) are turned on, so that the voltage value of the gate voltage of the fifth thin-film transistor (Q5) is pulled down to the ground voltage, and the charge / discharge control module (22) is in the off state. The fifth thin-film transistor (Q5) is turned off, the driving module (24) is turned off, and the light-emitting module (30) does not emit light.

[0060] When the first scan signal is switched from a high level to a low level and the second scan signal is switched from a low level to a high level, the light-emitting driving module (20) enters the discharge stage (T2), and the third scan signal maintains a high level. In this stage, the first thin-film transistor (Q1) is turned off and the data writing module (21) is turned off, so that the first capacitor (C1) stops energy charging and storage. The second thin-film transistor (Q2) to the fourth thin-film transistor (Q4) are all turned on and the charge / discharge control module (22) is turned on, so that the first capacitor (C1) can form a discharge circuit through the turned-on second thin-film transistor (Q2) to the fourth thin-film transistor (Q4), at which time the fifth thin-film transistor (Q5) is still in an off state, the driving module (24) is turned off, and the light-emitting module (30) does not emit light. In this step, as the discharge process proceeds, the end voltage of the first capacitor (C1) decreases to Vth when the discharge step (T2) ends; where Vth can correspond to the threshold voltage of the fifth thin-film transistor (Q5), and Vth is smaller than V.

[0061] When the first scan signal is switched from a low level to a high level and the second scan signal is switched from a high level to a low level, the third scan signal is switched from a high level to a low level, and the light-emitting driving module (20) enters the secondary energy storage stage (T3). In this stage, the first thin-film transistor (Q1) is turned on and the data writing module (21) is turned on to output a high-level data signal to the first capacitor (C1), and the terminal voltage of the first capacitor (C1) is charged again to V+Vth. At this time, although the fourth thin-film transistor (Q4) is turned on, the second thin-film transistor (Q2) and the third thin-film transistor (Q3) are turned off, and the charge / discharge control module (22) is in an off state. The fifth thin-film transistor (Q5) is still in an off state, the driving module (24) is turned off, and the light-emitting module (30) does not emit light.

[0062] When the first scan signal is switched back from a low level to a high level and the second scan signal is switched from a high level to a low level, the light-emitting driving module (20) enters the light-emitting driving step (T4), and the third scan signal maintains a low level. In this step, the first thin-film transistor (Q1) is turned off, the data writing module (21) is turned off, and the first capacitor (C1) stops energy charging and storage. Both the second thin-film transistor (Q2) and the fourth thin-film transistor (Q4) are turned on, and the first capacitor (C1) can output a discharge voltage (V+Vth) to the gate of the fifth thin-film transistor (Q5) via the turn-on of the turned-on second thin-film transistor (Q2). At this time, the third thin-film transistor (Q3) is turned off, and the charge / discharge control module (22) is turned on without pulling down the gate voltage of the fifth thin-film transistor (Q5). The fifth thin-film transistor (Q5) is turned on, and the driving module (24) is turned on to drive the light emission of the light-emitting module (30).

[0063] The technical solution of the present application adopts a design of two energy storage and one discharge in the light-emitting driving module (20), thereby ensuring that the control terminal voltage of the fifth thin-film transistor (Q5) becomes V+Vth in the light-emitting driving step (T4). This allows the fifth thin-film transistor (Q5) to effectively secure turn-on information and turn-on time in the light-emitting driving step (T4) compared to a design of one energy storage, which is advantageous for improving the light-emitting effect and operational stability of the light-emitting module (30).

[0064] As can be seen from the specific work process described above, if two or three thin-film transistors that should not be turned on simultaneously are in a turned-on state, it affects the light-emitting effect of the light-emitting module (30). For example, when the second thin-film transistor (Q2) and the third thin-film transistor (Q3) are turned on in the initial energy storage stage (T1), a ground discharge circuit of the first capacitor (C1) is formed, so that the terminal voltage of the first capacitor (C1) after completing the initial energy storage stage (T1) becomes lower than V, and the gate voltage value of the fifth thin-film transistor (Q5) becomes lower than V+Vth in the light-emitting driving stage (T4), so that the power air gap current output from the fifth thin-film transistor (Q5) to the light-emitting module (30) is lowered, and the light-emitting brightness of the light-emitting module (30) is lowered. Of course, in the above-described work step, there are additional cases where two or three thin-film transistors are turned on simultaneously and affect the final light-emitting effect of the light-emitting module (30), and a redundant explanation regarding this is omitted here. This also arises as a difficult problem in which the pixel unit of the self-emissive panel currently employs three scan signal driving methods, and by adopting the technical method of the present application, the probability of the above-described various cases occurring can be effectively reduced, thereby improving the display stability of the self-emissive panel.

[0065] Furthermore, referring to FIG. 6, the first scan signal is sequentially at the first level, second level, first level, second level in the initial energy storage stage (T1), discharge stage (T2), secondary energy storage stage (T3), and light emission driving stage (T4);

[0066] The level of the second scan signal in the initial energy storage stage (T1), discharge stage (T2), secondary energy storage stage (T3), and light emission driving stage (T4) is opposite to that of the first scan signal;

[0067] The third scan signal is sequentially at the first level, first level, second level, and second level in the initial energy storage stage (T1), discharge stage (T2), secondary energy storage stage (T3), and light emission driving stage (T4);

[0068] Here, the first level and the second level are opposite levels.

[0069] In this embodiment, one of the first level and the second level is a high level, and the other is a low level. In the embodiment illustrated in FIG. 3, the first thin-film transistor (Q1) to the fifth thin-film transistor (Q5) are all N-type thin-film transistors, the first level is a high level, and the second level is a low level. The probability that multiple thin-film transistors appear simultaneously turn on and the number of times when multiple scan signals perform level switching at the same time are proportional, and by adopting the light-emitting driving module (20) and the specific workflow thereof submitted in the technical solution of the present application, the number of times when 2-channel scan signals are simultaneously level-switched in one work step can be considered as two, and the number of times when 3-channel scan signals are simultaneously level-switched can be considered as one. By doing so, the number of times when multiple scan signals perform level switching at the same time is effectively reduced, and it can be understood that the probability of multiple thin-film transistors turning on simultaneously is realized through the mutual cooperation of the circuit structure and the control method.

[0070] In a specific embodiment, referring to FIG. 4, the signal generation module (10) is,

[0071] It includes an inverter (11) configured such that the input terminal and the output terminal are connected to correspond to the input terminal and the first output terminal of the signal generation module (10), and after performing inverting processing on the first scan signal, output it as a second scan signal.

[0072] The inverter (11) is a signal generation submodule of one of the signal generation modules (10), and the inverter (11) can be constructed by employing a switching element such as a thin-film transistor, MOS, or triode. The inverter (11) can perform level inverting processing on a connected first scan signal and can output the first scan signal after level inverting processing as a second scan signal. Specifically, when a first scan signal of a first level is connected, a second scan signal of a second level is output; and when a first scan signal of a second level is connected, a second scan signal of a first level is output. Since the inverter (11) performs optimization on the rising edge and falling edge of the signal during the inverting process, it can realize a reduction in the rising edge time and falling edge time of the second scan signal.

[0073] In a specific embodiment, referring to FIG. 5, the signal generation module (10) is,

[0074] The first input terminal is configured to be connected to a power supply voltage (VDD), and the second input terminal and output terminal are connected to correspond to the input terminal and second output terminal of the signal generation module (10), respectively, and the trigger (12) is configured to output the power supply voltage (VDD) as a second scan signal according to the first scan signal.

[0075] The trigger (12) is another signal generation submodule among the signal generation modules (10), and the trigger (12) can be realized by employing one or a combination of RS trigger, JK trigger, T trigger, and D trigger, and no limitation thereof is made here. In the present embodiment, the trigger (12) may be a T trigger, and the first input terminal, second input terminal, and output terminal of the trigger (12) may be the T input terminal, clock input terminal, and Q output terminal of the T trigger, respectively, and the first scan signal is used as the clock input of the T trigger. The T input terminal is configured so that a high-level power supply voltage (VDD) is connected via a resistor (R), and when the T trigger receives a low-level first scan signal, it directly outputs the high-level power supply voltage (VDD) as a high-level third scan signal, and whenever the high-level first scan signal is received, the T trigger inverts the level of the output signal once. Referring to FIG. 5, in the first energy storage stage (T1), the T trigger outputs a high-level third scan signal; in the second energy storage stage (T3), the high-level first scan signal is received again, and the T trigger outputs a low-level third scan signal. Additionally, since the area required for the installation of the inverter (11) and the trigger (12) is relatively small, it is convenient to install them in a concentrated manner in each pixel unit.

[0076] As illustrated in FIG. 6 and FIG. 3, FIG. 6 is a signal waveform of a first scan signal, a second scan signal, and a third scan signal output from the prior art. In order to ensure that the third scan signal is at a low level in the secondary energy storage stage (T3), level switching must be performed on the third scan signal in advance during the discharge stage (T2). If the third scan signal is switched to a low level too early or too late, it affects the discharge effect and secondary charge effect of the first capacitor (C1), respectively, and thus, a large amount of control must be performed on the self-luminous panel to ensure the display effect. The technical solution of the present application is advantageous for improving the mass production efficiency of the self-luminous panel because, through the characteristic of enabling rapid switching using the output level of the trigger (12), the first scan signal is switched from a low level to a high level, and the switching of the third scan signal from a high level to a low level is automatically completed, so too much control flow is not required.

[0077] Example 2:

[0078] The present application further provides a method for controlling a display panel.

[0079] Referring to FIG. 7, in Example 2, the control method of the display panel is,

[0080] After confirming that the pixel driving circuit has entered the operation phase, a first scan signal at the first level, a second scan signal at the second level, and a third scan signal at the first level are output to control the pixel driving circuit and enter the initial energy storage phase (T1);

[0081] A step of switching to and outputting a first scan signal at a second level when the first signal edge of the first pulse signal (TP1) is first detected, switching to and outputting a second scan signal at a first level when the second signal edge of the first pulse signal (TP1) is first detected, and switching to and outputting a third scan signal at a second level when the first signal edge or the second signal edge of the second pulse signal is first detected, thereby controlling the pixel driving circuit to enter a discharge step (T2);

[0082] A step of switching to and outputting a first scan signal at a first level when the first signal edge of the first pulse signal (TP1) is detected again, and switching to and outputting a second scan signal at a second level when the second signal edge of the first pulse signal (TP1) is detected again, thereby controlling the pixel driving circuit to enter a discharge step (T2);

[0083] The method includes the step of switching to and outputting a first scan signal at a second level when the first signal edge of the first pulse signal (TP1) is detected for the third time, and switching to and outputting a second scan signal at a first level when the second signal edge of the first pulse signal (TP1) is detected for the third time, thereby controlling the pixel driving circuit to enter a light emission driving step (T4);

[0084] Here, one of the first signal edge and the second signal edge is a rising edge, and the other is a falling edge.

[0085] In the present embodiment, the display panel may include a light-emitting module (30), a pixel driving circuit, and a timing control device (40); the input terminal of the pixel driving circuit is configured to be connected to a power supply voltage (VDD), and the output terminal of the pixel driving circuit is connected to the light-emitting module (30); and, in the timing control device (40), the four output terminals of the timing control device (40) are each connected in correspondence with the four control terminals of the pixel driving circuit, and the four output terminals of the timing control device (40) are configured to output a first scan signal, a second scan signal, a third scan signal, and a data signal to the pixel driving circuit, respectively, to control the pixel driving circuit and drive the light emission of the light-emitting module (30). Specifically, the four output terminals of the timing control device (40) are each connected in correspondence with the four control terminals of the light-emitting driving module (20) in the pixel driving circuit via three scan lines (L1) and one scan line (L2). The display panel may further be equipped with two pulse signal generating modules, each of which is connected to a timing control device (40), and the two pulse signal generating modules are configured to generate a pulse signal of one channel, namely a first pulse signal (TP1) and a second pulse signal, respectively, and output them to the timing control device (40), wherein each pulse signal of the channel may include a plurality of pulses having a rising edge and a falling edge. The timing control device (40) may perform level detection on the connected two-channel pulse signals, and when it is detected that the pulse signal of any one channel is switching from a low level to a high level, it may be determined that the rising edge of the pulse signal of that channel is detected; and when it is detected that the pulse signal of any one channel is switching from a high level to a low level, it may be determined that the falling edge of the pulse signal of that channel is detected.

[0086] The entity executing the control method of the display panel of the present application may be a timing control device. The pixel driving circuit may include a data writing module (21), a first switch module (22A), a second switch module (22B), a third switch module (22C), an energy storage module (23), and a driving module (24), and the circuit structure of each functional module in the pixel driving circuit may refer to the above-described embodiment 1, and a redundant description thereof is omitted here.

[0087] Here, we will proceed with a detailed analysis of the control method of the display panel of the present application, taking as an example where the first signal edge is a rising edge and the second signal edge is a falling edge. When the display panel is operated, the pixel driving circuit may have a plurality of work frame cycles that are executed cyclically under the control of the timing control device (40), and each work cycle may include a work step. Referring to FIG. 8, after it is confirmed that the pixel driving circuit has entered a work cycle, the timing control device (40) outputs a first scan signal at a first level, a second scan signal at a second level, and a third scan signal at a first level, thereby controlling the data writing module (21) to turn on and the charge / discharge control module (22) to turn off, and thereby controlling the pixel driving circuit to enter an initial energy storage stage (T1);

[0088] After the pixel driving circuit enters the initial energy storage stage (T1), when the rising edge of the first pulse signal (TP1) is detected by the timing control device (40), it is switched to output a first scan signal at the second level; when the falling edge of the first pulse signal (TP1) is detected, it is switched to output a second scan signal at the first level; when the rising edge or falling edge of the second pulse signal is detected, it is switched to output a third scan signal at the second level, thereby controlling the data writing module (21) to turn off and controlling the charge / discharge control module (22) to turn on, thereby controlling the pixel driving circuit to enter the discharge stage (T2); at this time, the first signal edge of the second pulse signal is set between the falling edge of the first pulse of the first signal pulse and the rising edge of the second pulse, and the third scan signal is already switched to the second level before the rising edge of the second pulse of the first signal pulse arrives.

[0089] After the pixel driving circuit enters the initial energy storage stage (T1), when the rising edge of the first pulse signal (TP1) is detected again by the timing control device (40), it switches to and outputs a first scan signal at a first level; when the falling edge of the first pulse signal (TP1) is detected, it switches to and outputs a second scan signal at a second level, thereby controlling the data writing module (21) to turn on and controlling the charge / discharge control module (22) to turn off, and controlling the pixel driving circuit to enter the discharge stage (T2);

[0090] After the pixel driving circuit enters the discharge stage (T2), when the rising edge of the first pulse signal (TP1) is detected by the timing control device (40), it switches to and outputs the first scan signal at the second level; when the falling edge of the first pulse signal (TP1) is detected, it switches to and outputs the second scan signal at the first level, thereby controlling the data writing module (21) to turn off, and controlling the charge / discharge control module (22) and the driving module (24) to turn on, and controlling the pixel driving circuit to enter the light emission driving stage (T4).

[0091] The control method of the display panel of the present application introduces two channels of pulse signals, and the timing control device (40) performs switching on the level of the three channels of scan signals according to the rising edge and falling edge of the pulse among the two channels of pulse signals, thereby using the interval time between the rising edge and falling edge of the same pulse to offset the level switching time of the three channels of scan signals, thereby reducing the probability that an overlapping portion occurs between the rising edge time and the falling edge time of each channel of scan signals, and reducing the probability that the overlapping portion affects the light emission effect of the pixel unit, and similarly solves the problem that the thin-film transistor in the light emission driving circuit is not turned off in time and affects the display effect of the display panel.

[0092] Example 3:

[0093] The present application further submits a display panel, and with reference to FIG. 9, the display panel includes a light-emitting module (30), a data line (L2), a scan line (L1), and a pixel driving circuit. The specific structure of the pixel driving circuit may be referenced in Example 1. Since the display panel adopts all the technical methods of Example 1 described above, it possesses at least all beneficial effects realized by the technical methods of Example 1 described above, and a redundant description thereof is omitted here.

[0094] Here, the light-emitting module (30) includes an organic light-emitting element, and the anode of the organic light-emitting element is configured to be connected to a power supply voltage (VDD) output from a pixel driving circuit, and the cathode of the organic light-emitting element is grounded; the scan line (L1) is configured to be connected to and transmit a first scan signal output from a gate driving device; the data line (L2) is configured to be connected to and transmit a data signal output from a source driving device; and the pixel driving circuit is connected to the light-emitting module (30), the data line (L2), and the scan line (L1), respectively.

[0095] Example 4:

[0096] The present application further submits a display panel, and with reference to FIG. 10, the display panel includes a light-emitting module (30), a pixel driving circuit, and a timing control device (40), and the timing control device (40) is configured to realize a control method of the display panel, and specific steps of the control method of the display panel may refer to Example 3, and since the display panel adopts all technical measures of Example 3 described above, it possesses at least all beneficial effects realized by the technical measures of Example 3 described above, and a redundant description thereof is omitted here.

[0097] Here, the light-emitting module (30) includes an organic light-emitting element, and the anode of the organic light-emitting element is configured to be connected to a power supply voltage (VDD) output from a pixel driving circuit, and the cathode of the organic light-emitting element is grounded; the pixel driving circuit is connected to the light-emitting module (30); the timing control device (40) is connected to four control terminals of the pixel driving circuit, and the timing control device (40) is configured to output a first scan signal, a second scan signal, a third scan signal, and a data signal to the pixel driving circuit via each of three scan lines (L1) and one scan line (L2), respectively, thereby controlling the pixel driving circuit to drive the light emission of the light-emitting module (30). Of course, the display panel may further include a gate driving device and a source driving device, and the gate driving device is configured to output a first scan signal, a second scan signal, and a third scan signal to the pixel driving circuit via each of three scan lines (L1) under the control of the timing control device (40); The source driving device is configured to output a data signal to the pixel driving circuit via the data line (L2) under the control of the timing control device (40).

[0098] The above description is merely a selectable embodiment of the present application and is not intended to limit the scope of the patent of the present application. Any equivalent structural transformation performed using the contents of the specification and attached drawings of the present application based on the inventive concept of the present application, or any application directly or indirectly in other related technical fields, is included within the scope of patent protection of the present application.

Claims

Claim 1 A pixel driving circuit, wherein the pixel driving circuit is applied to a display panel, and the display panel includes a data line, a scan line, and a light-emitting module, wherein the scan line is configured to connect and transmit a first scan signal and the source line is configured to connect and transmit a data signal, and the pixel driving circuit includes: a signal generation module, wherein the input terminal is connected to the scan line and the signal generation module is configured to generate a second scan signal according to the first scan signal and output it to a first output terminal; and a light-emitting driving module, wherein the first control terminal, the second control terminal, and the third control terminal are connected in correspondence with the scan line, the data line, and the first output terminal of the signal generation module, wherein the input terminal is configured to connect to a power supply voltage and the output terminal is connected to the light-emitting module, and wherein the light-emitting driving module is configured to drive the light-emitting module by writing the power supply voltage to the light-emitting module according to the received first scan signal, the second scan signal, and the data signal. Claim 2 A pixel driving circuit according to claim 1, wherein the signal generation module comprises two signal generation sub-modules, and the input terminals of the two signal generation sub-modules are each connected to a scan line corresponding to a located pixel unit to connect a first scan signal, and the two signal generation sub-modules are each configured to control the turn-on or turn-off of a corresponding switch element within themselves according to the level of the first scan signal to perform corresponding signal processing for the connected first scan signal. Claim 3 A pixel driving circuit according to claim 1, wherein the signal generation module is further configured to generate a third scan signal according to the first scan signal and output it to the fourth control terminal of the light-emitting driving module through the second output terminal, and the light-emitting driving module comprises: a data writing module in which the control terminal and input terminal are individually connected to the first control terminal and the second control terminal of the light-emitting driving module; a charge / discharge control module in which the first control terminal and the second control terminal are individually connected to the third control terminal and the fourth control terminal of the light-emitting driving module, and the input terminal is connected to the output terminal of the data writing module; an energy storage module connected between the output terminal of the data writing module and the input terminal of the charge / discharge control module; and a driving module in which the control terminal is connected to the output terminal of the charge / discharge control module, and the input terminal and output terminal are individually connected to the input terminal and output terminal of the light-emitting driving module. Claim 4 A pixel driving circuit according to claim 3, wherein the light-emitting driving module is configured to have three or more scan signals connected, and the signal generation module is characterized by having one channel of the scan signals connected and generating the scan signals of each of the remaining channels connected to the light-emitting driving module according to the scan signal of the connected channel. Claim 5 In paragraph 3, the pixel driving circuit is characterized by comprising: a first switch module in which a control terminal, an input terminal, and an output terminal are each connected to correspond to the first control terminal, an input terminal, and an output terminal of the charge / discharge control module; a second switch module in which a control terminal is connected to the second control terminal of the charge / discharge control module and an input terminal is connected to the output terminal of the first switch module; and a third switch module in which a control terminal is connected to the input terminal of the first switch module, an input terminal is connected to the output terminal of the second switch module, and an output terminal is grounded. Claim 6 In claim 3, the operation steps of the light-emitting driving module include an initial energy storage step, a discharge step, a secondary energy storage step, and a light-emitting driving step executed sequentially; in the initial energy storage step, the data writing module is turned on and the charge / discharge control module is turned off; in the discharge step, the data writing module is turned off and the charge / discharge control module is turned on and the driving module is turned off; in the secondary energy storage step, the data writing module is turned on and the charge / discharge control module is turned off; and in the light-emitting driving step, the data writing module is turned off and the charge / discharge control module and the driving module are turned on. Claim 7 A pixel driving circuit according to claim 6, wherein the first scan signal is sequentially at a first level, a second level, a first level, and a second level in the first energy storage stage, the discharge stage, the secondary energy storage stage, and the light emission driving stage; the level of the second scan signal in the first energy storage stage, the discharge stage, the secondary energy storage stage, and the light emission driving stage is opposite to that of the first scan signal; and the third scan signal is sequentially at a first level, a first level, a second level, and a second level in the first energy storage stage, the discharge stage, the secondary energy storage stage, and the light emission driving stage; and the first level and the second level are opposite levels. Claim 8 A pixel driving circuit according to claim 7, wherein the charge / discharge control module and the data writing module are not turned on simultaneously, the data writing module is turned on when the second scan signal and the third scan signal are both at the same level, and the data writing module is turned off when the second scan signal and the third scan signal are both at different levels. Claim 9 A pixel driving circuit characterized in that, in paragraph 2, the signal generation module is a signal generation submodule among the signal generation modules, and the input terminal and output terminal are connected in correspondence with the input terminal and first output terminal of the signal generation module, and the inverter is configured to output as the second scan signal after performing inverting processing on the first scan signal. Claim 10 A pixel driving circuit characterized by further including, in claim 9, a trigger in which the signal generation module is another signal generation sub-module among the signal generation modules, the first input terminal is configured to be connected to the power supply voltage, the second input terminal and the output terminal are connected to correspond to the input terminal and the second output terminal of the signal generation module, respectively, and the power supply voltage is configured to output the second scan signal according to the first scan signal. Claim 11 A pixel driving circuit characterized in that, in claim 10, the inverter is constructed by employing a switching element: a thin-film transistor, a MOS, or a triode; and the trigger is realized by employing one or a combination of multiple of an RS trigger, a JK trigger, a T trigger, or a D trigger. Claim 12 A method for controlling a display panel comprises: a step of, after confirming that the pixel driving circuit has entered a working step, outputting a first scan signal at a first level, a second scan signal at a second level, and a third scan signal at a first level to control the pixel driving circuit and enter an initial energy storage step; a step of, when the first signal edge of the first pulse signal is first detected, switching to and outputting the first scan signal at the second level, when the second signal edge of the first pulse signal is first detected, switching to and outputting the second scan signal at the first level, and when the first signal edge or the second signal edge of the second pulse signal is first detected, switching to and outputting the third scan signal at the second level to control the pixel driving circuit and enter a discharge step; A method for controlling a display panel, comprising: a step of switching to and outputting a first scan signal at a first level when the first signal edge of a first pulse signal is detected again, and switching to and outputting a second scan signal at a second level when the second signal edge of the first pulse signal is detected again, thereby controlling the pixel driving circuit to enter a discharge stage; a step of switching to and outputting a first scan signal at a second level when the first signal edge of the first pulse signal is detected a third time, and switching to and outputting a second scan signal at a first level when the second signal edge of the first pulse signal is detected a third time, thereby controlling the pixel driving circuit to enter a light emission driving stage; wherein one of the first signal edge and the second signal edge is a rising edge and the other is a falling edge. Claim 13 A display panel, wherein the display panel is configured to realize a control method of the display panel, and the display panel comprises: a light-emitting module; a pixel driving circuit connected to the light-emitting module; and a timing control device connected to four control terminals of the pixel driving circuit and configured to output a first scan signal, a second scan signal, a third scan signal, and a data signal to the pixel driving circuit to control the pixel driving circuit and drive the light emission of the light-emitting module. Claim 14 In claim 13, the display panel comprises a gate driving device and a source driving device, wherein the gate driving device is configured to output the first scan signal, the second scan signal, and the third scan signal to the pixel driving circuit via each of three scan lines under the control of the timing control device; and the source driving device is configured to output the data signal to the pixel driving circuit via a data line under the control of the timing control device. Claim 15 A display panel according to claim 14, wherein the entity executing the control method is the timing control device, and the timing control device, after confirming that the pixel driving circuit has entered the operation cycle, outputs the first scan signal, the second scan signal, and the third scan signal, controls the data writing module to turn on and the charge / discharge control module to turn off, and controls the pixel driving circuit to enter the initial energy storage stage. Claim 16 A display panel according to claim 15, characterized in that when a rising edge of a first pulse signal is detected by the timing control device, it switches to and outputs the first scan signal at a second level; when a falling edge of the first pulse signal is detected, it switches to and outputs the second scan signal at a first level; and when a rising edge or a falling edge of the second pulse signal is detected, it switches to and outputs the third scan signal at a second level, thereby controlling the data writing module to turn off, controlling the charge / discharge control module to turn on, and controlling the pixel driving circuit to enter the discharge stage. Claim 17 A display panel according to claim 16, characterized in that, after the pixel driving circuit enters the initial energy storage stage, when the rising edge of the first pulse signal is detected again by the timing control device, it switches to and outputs the first scan signal at the first level; and when the falling edge of the first pulse signal is detected, it switches to and outputs the second scan signal at the second level, thereby controlling the data writing module to turn on and controlling the charge / discharge control module to turn off, and controlling the pixel driving circuit to enter the discharge stage. Claim 18 A display panel according to claim 17, further comprising a driving module connected to the light-emitting module, wherein after the pixel driving circuit enters the discharge stage, when the rising edge of the first pulse signal is detected by the timing control device, the first scan signal at the second level is switched and output; and when the falling edge of the first pulse signal is detected, the second scan signal at the first level is switched and output, thereby controlling the data writing module to turn off, and controlling the charge / discharge control module and the driving module to turn on, and controlling the pixel driving circuit to enter the light-emitting driving stage.

Images