Display panel and display device

Abstract

A display panel and a display device. The display panel comprises a power supply circuit and at least one pixel driving circuit. When there are multiple pixel driving circuits, the power supply end of each pixel driving circuit is connected with the power supply circuit to receive a power supply voltage from the power supply circuit. By setting the power supply voltage as a stepwise increasing change mode: as the light emitting time elapses, the power supply voltage gradually increases. The increase of the power supply voltage causes the potential of the input end of the driving transistor in the pixel driving circuit to be lifted accordingly, and by accurately matching the step increment of the power supply voltage, the conduction current of the driving transistor in the pixel driving circuit can be kept substantially constant throughout the light emitting stage, thereby maintaining the driving current stable and eliminating brightness flicker.

Description

Technical Field

[0001] This application belongs to the field of display device technology, and in particular relates to a display panel and display device. Background Technology

[0002] Active-matrix organic light-emitting diode (AMOLED) display panels have gradually gained a foothold in the high-end mobile phone market due to their significant advantages in display color saturation, power consumption, and foldability.

[0003] In existing AMOLED pixel driving circuits, the voltage of some key nodes changes due to leakage current in the switching devices, which in turn changes the driving current supplied to the light-emitting devices, causing a flickering phenomenon in which the brightness of the light-emitting devices gradually decreases within a frame. Summary of the Invention

[0004] To address the problems existing in the prior art, the purpose of this application is to provide a display panel and a display device.

[0005] A first aspect of this application provides a display panel, comprising: a power supply circuit for providing a power supply voltage; at least one pixel driving circuit, wherein the power supply terminal of the pixel driving circuit is connected to the power supply circuit, the pixel driving circuit being configured to generate and output a driving current based on the received power supply voltage, the driving current being positively correlated with the power supply voltage; and during the light-emitting phase of the pixel driving circuit, the power supply voltage received by the pixel driving circuit increases in a stepwise manner.

[0006] In one embodiment, the pixel driving circuit is further configured to receive a data signal and a light emission control signal; the pixel driving circuit is configured to generate and output the driving current based on the power supply voltage according to the data signal when the light emission control signal is at an active level.

[0007] In one embodiment, during the light-emitting phase of the pixel driving circuit, the light-emitting control signal includes multiple valid level pulses.

[0008] In one embodiment, during the light-emitting phase of the pixel driving circuit, the power supply voltage increases for each effective level pulse of the light-emitting control signal.

[0009] In one embodiment, during the light-emitting phase of the pixel driving circuit, the power supply voltage increases in steps with the same increment value, and the duration of each step of the power supply voltage is the same.

[0010] In one embodiment, the duration is negatively correlated with the refresh rate of the display panel.

[0011] In one embodiment, the pixel driving circuit includes a voltage isolation module, a driving module, and a data writing module. The driving module is connected to the power supply circuit through the voltage isolation module. The voltage isolation module is used to write the power supply voltage to the power supply terminal of the driving module during the light-emitting phase of the pixel driving circuit. The driving module is used to generate and output the driving current based on the voltage of the power supply terminal of the driving module according to the voltage of the control node during the light-emitting phase of the pixel driving circuit. The data writing module is connected to the control node. The data writing module is used to configure the voltage of the control node according to the data signal during the data writing phase of the pixel driving circuit.

[0012] In one embodiment, the pixel driving circuit further includes an initialization module, which is connected to the control node and the output terminal of the driving module. The initialization module is used to configure the voltage of the output terminal of the control node and the driving module according to a reference voltage during the initialization phase of the pixel driving circuit.

[0013] In one embodiment, the display panel includes at least one light-emitting unit, the output terminal of the pixel driving circuit is connected to the light-emitting unit, and the pixel driving circuit is used to provide driving current to the light-emitting unit during the light-emitting phase.

[0014] A second aspect of this application provides a display device, including the display panel as described above.

[0015] The beneficial effects of this application embodiment compared to the prior art are as follows: by setting the power supply voltage to a stepped increasing variation mode, the power supply voltage gradually increases as the light emission time progresses. The increase in power supply voltage will correspondingly raise the potential at the input terminal of the driving transistor in the pixel driving circuit. By precisely matching the stepped increment of the power supply voltage, the conduction current of the driving transistor in the pixel driving circuit can be kept basically constant throughout the light emission stage, thereby maintaining stable driving current and eliminating brightness flicker. Attached Figure Description

[0016] Figure 1 A schematic diagram of a display panel provided in one embodiment of this application; Figure 2 This is a signal waveform diagram of a display panel provided in an embodiment of this application; Figure 3 A detailed circuit diagram of a pixel driving circuit provided in an embodiment of this application.

[0017] Reference numerals: 10, display panel; 100, power supply circuit; 200, pixel driving circuit; 210, voltage isolation module; 220, driving module; 230, data writing module; 240, initialization module; 300, light-emitting unit. Detailed Implementation

[0018] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0019] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0020] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0022] Figure 1 A schematic diagram of a display panel 10 according to an embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, and the details are as follows: A display panel 10 includes a power supply circuit 100 and at least one pixel driving circuit 200. The pixel driving circuit 200 is a circuit composed of multiple thin-film transistors and energy storage capacitors, used to control the magnitude of the output driving current according to a data signal Vdata, thereby controlling the brightness of the corresponding light-emitting unit 300 to achieve grayscale display.

[0023] The power supply circuit 100 is used to provide the power supply voltage ELVDD.

[0024] The power supply terminal of the pixel driving circuit 200 is connected to the power supply circuit 100. The pixel driving circuit 200 generates and outputs a driving current based on the received power supply voltage ELVDD, and the driving current is positively correlated with the power supply voltage ELVDD. The output terminal of the pixel driving circuit 200 can be connected to the corresponding light-emitting unit 300 to provide driving current to the light-emitting unit 300.

[0025] It is understandable that when there are multiple pixel driving circuits 200, the power supply terminal of each pixel driving circuit 200 is connected to the power supply circuit 100 to receive the power supply voltage ELVDD from the power supply circuit 100.

[0026] like Figure 2 As shown, during the light-emitting phase of the pixel driving circuit 200, the power supply voltage ELVDD received by the pixel driving circuit 200 increases in a step-like manner. The light-emitting phase is one stage in the operation of the pixel driving circuit 200. During this phase, the pixel driving circuit 200 generates and outputs a driving current to illuminate the corresponding light-emitting unit 300. Specifically, the step-like increase refers to the power supply voltage ELVDD gradually increasing over time in a step-like manner. That is, the power supply voltage ELVDD remains constant within each time period, and after reaching the switching moment, the power supply voltage ELVDD jumps to a higher voltage level and remains there.

[0027] It should be noted that during the light-emitting stage of the pixel driving circuit 200, if the driving transistor in the pixel driving circuit 200 is a P-type transistor, the potential of the control terminal of the driving transistor is prone to gradually rising due to leakage. Under the condition that the power supply voltage ELVDD remains unchanged, the driving current will decrease accordingly, causing the light-emitting brightness of the corresponding light-emitting unit 300 to decay, thereby producing brightness flicker within one frame.

[0028] This embodiment sets the power supply voltage ELVDD in a stepped increasing pattern: as the light emission time progresses, the power supply voltage ELVDD gradually increases. The increase in power supply voltage ELVDD causes the potential at the input terminal of the driving transistor in the pixel driving circuit 200 to rise accordingly. By precisely matching the stepped increment of the power supply voltage ELVDD, the conduction current of the driving transistor in the pixel driving circuit 200 can be kept basically constant throughout the light emission stage, thereby maintaining stable driving current and eliminating brightness flicker.

[0029] In this embodiment, only the timing output of the power supply voltage ELVDD is adjusted. The structure of the pixel driving circuit 200 can adopt existing circuit designs, such as common pixel structures like 2T1C, 3T1C, or 7T1C, without the need to add switching devices or change the layout design.

[0030] In some embodiments, the power supply circuit 100 may include a programmable power chip that receives control signals via a digital interface and outputs a stepped-incrementing power supply voltage ELVDD. The programmable power chip integrates a voltage regulation module and a timing control module, enabling it to adjust the output voltage step-by-step according to preset step parameters during the light-emitting phase. The step parameters include the initial voltage value, voltage step size, number of steps, duration of each step, and voltage switching time.

[0031] In one embodiment, such as Figure 3 As shown, the pixel driving circuit 200 is also used to receive the data signal Vdata and the light emission control signal EM.

[0032] The pixel driving circuit 200 is used to generate and output a driving current based on the power supply voltage ELVDD according to the data signal Vdata when the light emission control signal EM is at an active level.

[0033] The operation of the pixel driving circuit 200 is divided into several stages, including a data writing stage and a light-emitting stage. During the data writing stage, the light-emitting control signal EM is at an invalid level, and the light-emitting path of the pixel driving circuit 200 is turned off; the data signal Vdata is written to the control node M. During the light-emitting stage, the light-emitting control signal EM becomes valid, turning on the light-emitting path of the pixel driving circuit 200. At this time, the pixel driving circuit 200 generates a driving current based on the voltage of the control node M and the power supply voltage ELVDD, driving the light-emitting unit 300 to emit light. The valid and invalid levels depend on the specific circuit design; for example, the valid level can be low, and the invalid level can be high.

[0034] The stepwise increase in power supply voltage ELVDD occurs during the light emission phase, specifically when the light emission control signal EM is active. Since the data signal Vdata has already been written during the data writing phase, changes in power supply voltage ELVDD do not affect the accuracy of data writing; current compensation is only implemented during the light emission phase. This ensures that the driving current remains stable throughout the entire light emission phase, effectively eliminating brightness flicker within a frame. This embodiment, by introducing the light emission control signal EM, strictly separates the data writing and light emission phases in time, further improving the operational reliability of the pixel driving circuit 200.

[0035] By precisely controlling the start and end of the light-emitting phase through the level switching of the light-emitting control signal EM, it can be ensured that the step-by-step increase of the power supply voltage ELVDD only applies during the light-emitting period, avoiding unnecessary power consumption during the non-light-emitting phase.

[0036] In one embodiment, such as Figure 2 As shown, during the light-emitting stage of the pixel driving circuit 200, the light-emitting control signal EM includes multiple valid level pulses.

[0037] During the light-emitting phase, the light-emitting control signal EM is not a single continuous effective level pulse, but rather consists of multiple effective level pulses, with invalid level pulses interspersed between each effective level pulse. By independently adjusting the width and number of effective level pulses, the light-emitting duration within each sub-light-emitting cycle can be flexibly controlled, thereby achieving finer dimming and grayscale control. Specifically, the number and width of the effective level pulses can be dynamically adjusted according to the refresh rate of the display panel 10, the target brightness, and grayscale requirements. For example, in low-brightness mode, the number of effective level pulses can be reduced or the width of the effective level pulses can be shortened to reduce the total light-emitting duration. In high-brightness mode, the number of effective level pulses can be increased or the width of the effective level pulses can be lengthened to increase the total light-emitting duration. In high refresh rate mode, the number of effective level pulses can be reduced, and in low refresh rate mode, the number of effective level pulses can be increased to ensure that the power supply voltage ELVDD has sufficient voltage compensation steps at different refresh rates.

[0038] One valid level pulse and an adjacent invalid level pulse correspond to one light-emitting sub-interval. Within each light-emitting sub-interval, the power supply voltage ELVDD maintains a relatively stable stepped voltage value, driving the light-emitting unit 300 to emit light. During the valid level pulse interval, the light-emitting control signal EM is at an invalid level, the light-emitting unit 300 stops emitting light, and the power supply voltage ELVDD can complete the stepped switching at this time. By dividing the light-emitting stage into multiple short pulses, each valid level pulse corresponds to a voltage step, and the stepped increase of the power supply voltage ELVDD is synchronized with the valid level pulse. The power supply voltage ELVDD maintains the current stepped voltage during each valid level pulse, and the voltage switching is completed within the valid level pulse interval.

[0039] For example, in some embodiments, in each light-emitting stage, the light-emitting control signal EM includes four valid level pulses, corresponding to four light-emitting sub-intervals, and the power supply voltage ELVDD is correspondingly set to four stepped voltage values ​​(specifically 4.6V, 4.65V, 4.7V, and 4.75V), with a step value of 0.05V. Within each light-emitting sub-interval, the power supply voltage ELVDD maintains the current stepped value, driving the light-emitting unit 300 to emit light stably.

[0040] In one embodiment, such as Figure 2 As shown, during the light-emitting stage of the pixel driving circuit 200, the power supply voltage ELVDD corresponding to each effective level pulse of the light-emitting control signal EM increases.

[0041] The power supply voltage ELVDD increases sequentially, meaning the first valid level pulse corresponds to the first-level power supply voltage ELVDD, the second valid level pulse corresponds to the second-level power supply voltage ELVDD, and so on, with the Nth valid level pulse corresponding to the Nth-level power supply voltage ELVDD. The specific voltage value of the power supply voltage ELVDD increases monotonically with the pulse sequence number.

[0042] By gradually increasing the power supply voltage ELVDD corresponding to each effective level pulse, the cumulative effect of leakage current can be precisely matched, so that the light emission brightness of the light-emitting unit 300 corresponding to each effective level pulse is the same, avoiding brightness differences between effective level pulses.

[0043] The increment (step value) of the power supply voltage ELVDD can be calibrated according to the actual leakage current accumulation to ensure that the drive current of each effective level pulse is consistent.

[0044] In one embodiment, such as Figure 2 As shown, during the light-emitting phase of the pixel driving circuit 200, the power supply voltage ELVDD increases in steps with the same increment value, and the duration of each step of the power supply voltage ELVDD is the same. Specifically, the increment value refers to the difference between two adjacent voltage steps, which can be set according to the leakage characteristics of the display panel 10, the light-emitting duration of a single light-emitting sub-area, and the target brightness uniformity requirements. The duration is the length of time that each voltage step of the power supply voltage ELVDD remains stable, i.e., the duration of each step.

[0045] When the leakage rate is approximately constant, using a stepped voltage with equal steps and durations is the simplest and most effective compensation method. At equal sustaining times, the power supply voltage ELVDD increases by a fixed step value, keeping the drive current essentially stable.

[0046] The design with equal steps and equal duration simplifies the implementation of the power supply circuit 100: only a fixed clock cycle and a fixed voltage increment are needed to generate the entire stepped waveform without the need for complex nonlinear control algorithms.

[0047] In some embodiments, the step value and hold time of the power supply voltage ELVDD can be calibrated according to the actual leakage characteristics of the display panel 10. For example, by measuring the leakage rate at different gray levels and temperatures, the optimal combination of step value and hold time can be determined to achieve personalized calibration.

[0048] In one embodiment, the duration of the hold is negatively correlated with the refresh rate of the display panel 10.

[0049] Understandably, a higher refresh rate results in a shorter frame period. While maintaining the same number of steps, the duration of each step needs to be shortened accordingly to accommodate the shorter frame period. Conversely, as the refresh rate decreases, the frame period lengthens, allowing for a corresponding increase in duration to ensure that the complete step compensation process can be completed within each photon interval. This dynamic adjustment of duration ensures precise matching of the compensation waveform to the frame structure at different refresh rates, preventing insufficient or excessive compensation steps due to frame period variations, thereby maintaining the stability of the driving current and the consistency of luminous brightness.

[0050] Specifically, in some embodiments, the duration is 8.25ms when the refresh rate is 120Hz. That is, at a 120Hz refresh rate, the power supply voltage ELVDD increases by one step every 8.25ms during each emission stage.

[0051] Specifically, in some embodiments, the duration is 33ms at a refresh rate of 30Hz. That is, at a 30Hz refresh rate, the power supply voltage ELVDD increases by one step every 33ms during each emission stage.

[0052] In one embodiment, such as Figure 3 As shown, the pixel driving circuit 200 includes a voltage isolation module 210, a driving module 220, and a data writing module 230.

[0053] The driving module 220 is connected to the power supply circuit 100 through the voltage isolation module 210. The voltage isolation module 210 is used to write the power supply voltage ELVDD into the power supply terminal of the driving module 220 during the light emission stage of the pixel driving circuit 200. The driving module 220 is used to generate and output the driving current based on the voltage of the power supply terminal of the driving module 220 according to the voltage of the control node M during the light emission stage of the pixel driving circuit 200.

[0054] The data writing module 230 is connected to the control node M. The data writing module 230 is used to configure the voltage of the control node M according to the data signal Vdata during the data writing stage of the pixel driving circuit 200.

[0055] The voltage isolation module 210 is turned on during the light-emitting phase of its respective pixel driving circuit 200 and turned off during other phases, thereby preventing the step changes in the power supply voltage ELVDD during the non-light-emitting phase from affecting the driving module 220. Through the switching control of the voltage isolation module 210, independent light-emitting control of each pixel can be achieved when multiple pixel driving circuits 200 share the same power supply circuit 100. This avoids interference with the data writing or threshold compensation process of other pixels due to step changes in the power supply voltage ELVDD, thereby improving the overall display uniformity and reliability of the display panel 10. Specifically, the voltage isolation module 210 can be briefly turned on before each effective level pulse of the light-emitting control signal EM, so that the power supply voltage ELVDD is written to the power supply terminal of the driving module 220 before each effective level pulse of the light-emitting control signal EM. This ensures that at the beginning of each effective level pulse of the light-emitting control signal EM, the power supply terminal voltage of the driving module 220 has stabilized at the corresponding power supply voltage ELVDD, thus guaranteeing the accuracy of the driving current and the uniformity of the light emission brightness.

[0056] In one embodiment, such as Figure 3 As shown, the pixel driving circuit 200 also includes an initialization module 240, which is connected to the control node M and the output terminal of the driving module 220. The initialization module 240 is used to configure the voltage of the control node M and the output terminal of the driving module 220 according to the reference voltage Vrefn during the initialization phase of the pixel driving circuit 200.

[0057] The initialization module 240 resets the control node M and the output terminal to the reference voltage Vrefn, eliminating the historical charge of the previous frame and ensuring that the starting state of each frame is consistent. Periodic initialization can avoid the cumulative drift of pixel node voltage and reduce the image sticking problem after displaying static images for a long time.

[0058] In some embodiments, the voltage isolation module 210 includes an isolation transistor T0, the driving module 220 includes a first transistor T1, a second transistor T2 and a third transistor T3, the data writing module 230 includes a fourth transistor T4, a fifth transistor T5 and an energy storage capacitor, and the initialization module 240 includes a sixth transistor T6 and a seventh transistor T7.

[0059] The first terminal of the isolation transistor T0 is connected to the power supply circuit 100, the second terminal of the isolation transistor T0 is connected to the first terminal of the first transistor T1, and the control terminal of the isolation transistor T0 is used to receive the isolation control signal Gn. The second terminal of the first transistor T1 is connected to the first terminal of the second transistor T2, the second terminal of the second transistor T2 is connected to the first terminal of the third transistor T3, the second terminal of the third transistor T3 is connected to the light-emitting unit 300, the control terminals of the first transistor T1 and the third transistor T3 are used to receive the light-emitting control signal EM, and the control terminal of the second transistor T2 is connected to the control node M.

[0060] The first terminal of the fourth transistor T4 is used to receive the data signal Vdata. The second terminal of the fourth transistor T4 is connected to the first terminal of the second transistor T2. The first terminal of the fifth transistor T5 is connected to the second terminal of the second transistor T2, and the second terminal of the fifth transistor T5 is connected to the control node M. The first terminal of the energy storage capacitor C1 is connected to the first terminal of the first transistor T1, and the second terminal of the energy storage capacitor C1 is connected to the control node M. The control terminals of both the fourth transistor T4 and the fifth transistor T5 are used to receive the first control signal S1.

[0061] The first terminal of the sixth transistor T6 is used to receive the reference voltage Vrefn, and the second terminal of the sixth transistor T6 is connected to the control node M. The first terminal of the seventh transistor T7 is used to receive the reference voltage Vrefn, and the second terminal of the seventh transistor T7 is connected to the second terminal of the third transistor T3. The control terminal of the sixth transistor T6 is used to receive the second control signal S2, and the control terminal of the seventh transistor T7 is used to receive the third control signal S3.

[0062] Among them, the isolation transistor T0, the first transistor T1, the second transistor T2, the third transistor T3, the fourth transistor T4, the fifth transistor T5, the sixth transistor T6, and the seventh transistor T7 are all P-type thin-film transistors (TFTs). Each transistor can be fabricated using a low-temperature polycrystalline silicon (LTPS) process.

[0063] In some embodiments, pixel driving circuits 200 belonging to the same row can share the same voltage isolation module 210. That is, the power supply terminals of the driving modules 220 of each pixel driving circuit 200 can be connected to each other through the same trace, thereby realizing the row-by-row writing of the power supply voltage ELVDD and avoiding display abnormalities caused by the simultaneous change of the entire screen when the power supply voltage ELVDD changes.

[0064] For example, in some embodiments, the operation of the pixel driving circuit 200 within one frame can be divided into three stages: initialization stage, data writing stage and light emission stage, which are performed sequentially.

[0065] During the initialization phase, the second control signal S2 and the third control signal S3 may include active levels, turning on the sixth transistor T6 and the seventh transistor T7. A reference voltage Vrefn is applied to the control node M through the sixth transistor T6, and simultaneously to the second terminal of the third transistor T3 (i.e., the input terminal of the light-emitting unit 300) through the seventh transistor T7, resetting both the control node M and the input terminal of the light-emitting unit 300 to the reference voltage Vrefn, eliminating residual charge from the previous frame. The data writing phase then begins.

[0066] During the data writing phase, the first control signal S1 includes an active level, turning on the fourth transistor T4 and the fifth transistor T5. The data signal Vdata is written to the first terminal of the second transistor T2 through the fourth transistor T4, and charges the energy storage capacitor through the fifth transistor T5 and the turned-on second transistor T2, causing the voltage of the control node M to gradually change. When the voltage of the control node M stabilizes, the data writing phase ends. At this point, the voltage of the control node M is the sum of the data voltage and the threshold voltage of the second transistor T2, completing the threshold voltage compensation, and then the light-emitting phase begins.

[0067] During the light-emitting phase, the light-emitting control signal EM includes an active level, turning on the first transistor T1 and the third transistor T3. Whenever the first transistor T1 and the third transistor T3 are turned on, the second transistor T2 is in saturation. The drive current flows through the first transistor T1, the second transistor T2, and the third transistor T3 to the light-emitting unit 300, causing the light-emitting unit 300 to emit light. The specific magnitude of the drive current is determined by the voltage of the control node M and the received power supply voltage ELVDD. By increasing the power supply voltage ELVDD in a stepwise manner, the gate-source voltage of the second transistor T2 can be kept relatively stable even when the gate voltage of the second transistor T2 changes due to leakage current.

[0068] During the emission phase, the emission control signal EM is not a single continuous effective level pulse, but rather consists of multiple effective level pulses with intervals between them, forming a pulse train structure. By independently adjusting the width and number of effective level pulses, the emission duration within each sub-emission cycle can be flexibly controlled, thereby achieving finer dimming and grayscale control.

[0069] In one embodiment, the display panel 10 includes at least one light-emitting unit 300, and the output terminal of the pixel driving circuit 200 is connected to the light-emitting unit 300. The pixel driving circuit 200 is used to provide driving current to the light-emitting unit 300 during the light-emitting stage.

[0070] The display panel 10 may include multiple light-emitting units 300, each light-emitting unit 300 corresponding to a sub-pixel, and each sub-pixel is independently driven by a corresponding pixel driving circuit 200 to achieve precise brightness control.

[0071] Specifically, the light-emitting unit 300 may include a light-emitting diode (LED) D1. The anode of the LED D1 is connected to the output terminal of the pixel driving circuit 200, and the cathode is connected to the common low potential ELVSS. During the light-emitting phase, the pixel driving circuit 200 provides a stable driving current to the LED D1, causing the LED D1 to emit light of a corresponding brightness. Through the step-by-step compensation of the power supply voltage ELVDD, the driving current of the LED D1 remains stable within a frame, thereby effectively suppressing the brightness decay and flickering of the LED D1, and improving the display uniformity and image quality of the display panel 10.

[0072] This application also provides a display device, which includes a display panel 10 as described in any of the above embodiments.

[0073] The display panel 10 includes a power supply circuit 100 and at least one pixel driving circuit 200. The pixel driving circuit 200 is a circuit composed of multiple thin-film transistors and energy storage capacitors, used to control the magnitude of the output driving current according to the data signal Vdata, thereby controlling the brightness of the corresponding light-emitting unit 300 to achieve grayscale display.

[0074] The power supply circuit 100 is used to provide the power supply voltage ELVDD.

[0075] The power supply terminal of the pixel driving circuit 200 is connected to the power supply circuit 100. The pixel driving circuit 200 generates and outputs a driving current based on the received power supply voltage ELVDD, and the driving current is positively correlated with the power supply voltage ELVDD. The output terminal of the pixel driving circuit 200 can be connected to the corresponding light-emitting unit 300 to provide driving current to the light-emitting unit 300.

[0076] It is understandable that when there are multiple pixel driving circuits 200, the power supply terminal of each pixel driving circuit 200 is connected to the power supply circuit 100 to receive the power supply voltage ELVDD from the power supply circuit 100.

[0077] During the light-emitting phase of the pixel driving circuit 200, the power supply voltage ELVDD received by the pixel driving circuit 200 increases in a step-like manner. The light-emitting phase is one stage in the operation of the pixel driving circuit 200, during which the pixel driving circuit 200 generates and outputs driving current to illuminate the corresponding light-emitting unit 300. Specifically, the step-like increase refers to the power supply voltage ELVDD gradually increasing over time in a step-like manner; that is, the power supply voltage ELVDD remains constant within each time period, and after reaching the switching moment, the power supply voltage ELVDD jumps to a higher voltage level and remains there.

[0078] It should be noted that during the light-emitting stage of the pixel driving circuit 200, if the driving transistor in the pixel driving circuit 200 is a P-type transistor, the potential of the control terminal of the driving transistor is prone to gradually rising due to leakage. Under the condition that the power supply voltage ELVDD remains unchanged, the driving current will decrease accordingly, causing the light-emitting brightness of the corresponding light-emitting unit 300 to decay, thereby producing brightness flicker within one frame.

[0079] This embodiment sets the power supply voltage ELVDD in a stepped increasing pattern: as the light emission time progresses, the power supply voltage ELVDD gradually increases. The increase in power supply voltage ELVDD causes the potential at the input terminal of the driving transistor in the pixel driving circuit 200 to rise accordingly. By precisely matching the stepped increment of the power supply voltage ELVDD, the conduction current of the driving transistor in the pixel driving circuit 200 can be kept basically constant throughout the light emission stage, thereby maintaining stable driving current and eliminating brightness flicker.

[0080] The display devices in this application include, but are not limited to, mobile phones, personal digital assistants (PDAs), tablet computers, e-books, televisions, access control systems, smart landline phones, control consoles, and other devices with display functions.

[0081] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0082] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0083] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A display panel, characterized in that, include: A power supply circuit (100) is used to provide a power supply voltage; At least one pixel driving circuit (200) is provided, the power supply terminal of the pixel driving circuit (200) is connected to the power supply circuit (100), the pixel driving circuit (200) is used to generate and output a driving current based on the received power supply voltage, the driving current being positively correlated with the power supply voltage; During the light-emitting phase of the pixel driving circuit (200), the power supply voltage received by the pixel driving circuit (200) increases in a stepwise manner.

2. The display panel as described in claim 1, characterized in that, The pixel driving circuit (200) is also used to receive data signals and light emission control signals; The pixel driving circuit (200) is used to generate and output the driving current based on the power supply voltage according to the data signal when the light emission control signal is at an effective level.

3. The display panel as described in claim 2, characterized in that, During the light-emitting phase of the pixel driving circuit (200), the light-emitting control signal includes multiple valid level pulses.

4. The display panel as described in claim 3, characterized in that, During the light-emitting phase of the pixel driving circuit (200), the power supply voltage increases for each valid level pulse of the light-emitting control signal.

5. The display panel as described in claim 1, characterized in that, During the light-emitting phase of the pixel driving circuit (200), the power supply voltage increases in steps with the same step value, and the duration of each step of the power supply voltage is the same.

6. The display panel as described in claim 5, characterized in that, The duration of the hold is negatively correlated with the refresh rate of the display panel.

7. The display panel as described in any one of claims 1 to 6, characterized in that, The pixel driving circuit (200) includes a voltage isolation module (210), a driving module (220), and a data writing module (230). The driving module (220) is connected to the power supply circuit (100) through the voltage isolation module (210). The voltage isolation module (210) is used to write the power supply voltage into the power supply terminal of the driving module (220) during the light emission stage of the pixel driving circuit (200). The driving module (220) is used to generate and output the driving current based on the voltage of the power supply terminal of the driving module (220) according to the voltage of the control node during the light emission stage of the pixel driving circuit (200). The data writing module (230) is connected to the control node. The data writing module (230) is used to configure the voltage of the control node according to the data signal during the data writing stage of the pixel driving circuit (200).

8. The display panel as described in claim 7, characterized in that, The pixel driving circuit (200) further includes an initialization module (240), which is connected to the output terminals of the control node and the driving module (220). The initialization module (240) is used to configure the voltage of the output terminals of the control node and the driving module (220) according to the reference voltage during the initialization phase of the pixel driving circuit (200).

9. The display panel as described in any one of claims 1 to 6, characterized in that, The display panel includes at least one light-emitting unit (300), and the output terminal of the pixel driving circuit (200) is connected to the light-emitting unit (300). The pixel driving circuit (200) is used to provide driving current to the light-emitting unit (300) during the light-emitting phase.

10. A display device, characterized in that, Includes the display panel as described in any one of claims 1 to 9.

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