CN117153085A - Display panel, driving method thereof and display device - Google Patents

Abstract

The invention discloses a display panel, a driving method thereof and a display device, wherein the display panel comprises a scanning driving circuit and a plurality of rows of pixel driving circuits, one output end of the scanning driving circuit is connected with the pixel driving circuits of the corresponding rows, and the scanning driving circuit is used for transmitting sweep frequency signals to the pixel driving circuits of the corresponding rows step by step; the pixel driving circuit comprises a coupling module, a driving module and a light emitting module, wherein the driving module and the light emitting module are connected between a first power line and a second power line, the coupling module is connected between the output end of the scanning driving circuit and the control end of the driving module, and the driving module is used for controlling the light emitting time of the light emitting module according to the data voltage and the sweep frequency signal; the sweep frequency signal is a continuously-changing voltage signal, and the voltage output by the scanning driving circuit is a step voltage associated with the sweep frequency signal. The technical scheme provided by the embodiment of the invention can realize progressive scanning display of the pixel driving circuit, thereby being beneficial to improving the problem of flicker of a display picture.

Description

Display panel, driving method thereof and display device

Technical Field

The present invention relates to the field of display technologies, and in particular, to a display panel, a driving method thereof, and a display device.

Background

With the continuous development of display technology, micro light emitting diodes (Micro light emitting diode, micro-LEDs) are widely applied in the display field by virtue of the advantages of wide color gamut, fast response speed, high brightness, long service life and the like.

Currently, micro-LED display panels generally include a pixel circuit and a light emitting element, where the pixel circuit generally uses a digital driving method to control the light emitting element to emit light. However, the display panel in the prior art is easy to generate a picture flickering phenomenon in the display process, so that the display effect is reduced.

Disclosure of Invention

The invention provides a display panel, a driving method thereof and a display device, which are used for realizing progressive scanning of a pixel driving circuit so as to improve the flicker phenomenon of a display picture.

According to an aspect of the present invention, there is provided a display panel including a scan driving circuit and a plurality of rows of pixel driving circuits, an output end of the scan driving circuit being connected to the pixel driving circuits of a corresponding row, the scan driving circuit being configured to transmit a sweep signal to the pixel driving circuits of the corresponding row step by step;

the pixel driving circuit comprises a coupling module, a driving module and a light emitting module, wherein the driving module and the light emitting module are connected between a first power line and a second power line, the coupling module is connected between the output end of the scanning driving circuit and the control end of the driving module, and the driving module is used for controlling the light emitting time of the light emitting module according to data voltage and the sweep frequency signal;

The sweep frequency signal is a continuously-changing voltage signal, and the voltage output by the scanning driving circuit is a step voltage associated with the sweep frequency signal.

Optionally, each output end of the scanning driving circuit is correspondingly connected with a first end of a coupling module of one row of the pixel driving circuits, a second end of the coupling module is connected with a control end of the driving module, and the scanning driving circuit is configured to transmit the sweep frequency signal to the first end of the coupling module row by row in a light emitting stage.

Optionally, the scanning driving circuit includes n-level signal transmission modules, the output end of the signal transmission module of the upper level is connected with the input end of the signal transmission module of the lower level, wherein the input end of the signal transmission module of the first level is connected with the sweep frequency signal; the output end of each stage of signal transmission module is used as an output end of the scanning driving circuit and is connected with the corresponding pixel driving circuit; wherein n is the number of rows of the pixel driving circuit.

Optionally, the control end of the signal transmission module of the odd-numbered stage is connected with a first clock signal line, and the control end of the signal transmission module of the even-numbered stage is connected with a second clock signal line; the first clock signal transmitted on the first clock signal line and the second clock signal transmitted on the second clock signal line are complementary signals.

Optionally, the signal transmission module includes a switch unit and a storage unit, wherein a first end of the switch unit is used as an input end of the signal transmission module, a second end of the switch unit is used as an output end of the signal transmission module, a control end of the switch unit is used as a control end of the signal transmission module, and the storage unit is connected between the first end and the second end of the switch unit;

preferably, the switching unit includes a switching transistor, and the memory unit includes a storage capacitor.

Optionally, the driving module includes a data writing unit, a first driving unit, an initializing unit, and a light emission control unit, where the light emission control unit and the first driving unit are connected between the first power line and a first end of the light emitting module, a second end of the light emitting module is connected to the second power line, the data writing unit is configured to write the data voltage to a control end of the first driving unit in a data writing stage, the initializing unit is configured to transmit an initializing voltage to a first end and a second end of the coupling module in an initializing stage, the first end of the coupling module is connected to an output end of the scan driving circuit, and the second end of the coupling module is connected to a control end of the first driving unit;

Preferably, the driving module further includes a compensation unit connected between the second end and the control end of the first driving unit, and the data writing unit is connected between the data line and the first end of the first driving unit.

Optionally, the coupling module includes a coupling capacitor, the first driving unit includes a first driving transistor, the data writing unit includes a data writing transistor, the compensating unit includes a compensating transistor, the initializing unit includes a first initializing transistor and a second initializing transistor, and the light emission control unit includes a first light emission control transistor and a second light emission control transistor;

the first electrode of the first light-emitting control transistor is connected with the first power line, the second electrode of the first light-emitting control transistor is connected with the first electrode of the first driving transistor, the second electrode of the first driving transistor is connected with the first end of the light-emitting module through the second light-emitting control transistor, and the grid electrode of the first light-emitting control transistor and the grid electrode of the second light-emitting control transistor are both connected with a light-emitting control signal line; the first electrode of the first initializing transistor and the first electrode of the second initializing transistor are connected with an initializing signal line, the second electrode of the first initializing transistor is connected with the first end of the coupling capacitor, the second electrode of the second initializing transistor is connected with the second end of the coupling capacitor, the first end of the coupling capacitor is connected with the output end of the scanning driving circuit, the second end of the coupling capacitor is connected with the gate of the first driving transistor, the compensating transistor is connected between the second electrode and the gate of the first driving transistor, and the gate of the compensating transistor and the gate of the data writing transistor are connected with the second scanning line; the first pole of the data writing transistor is connected with the data line, and the second pole of the data writing transistor is connected with the first pole of the first driving transistor.

Optionally, the driving module includes a data writing unit, a first driving unit, a second driving unit, a compensating unit, an initializing unit, a resetting unit and a light emitting control unit, where the data writing unit is connected between a data line and a first end of the coupling module, a second end of the coupling module is connected with a control end of the first driving unit, the first driving unit is connected between a first power line and a control end of the second driving unit, the second driving unit and the light emitting control unit are connected between the first power line and a first end of the light emitting module, and a second end of the light emitting module is connected with the second power line;

the compensation unit is connected between the second end and the control end of the first driving unit, the reset unit is used for transmitting an initialization voltage to the control end of the second driving unit in a reset stage, and the initialization unit is used for transmitting the initialization voltage to the first end and the second end of the coupling module in the initialization stage;

preferably, the first driving unit includes a first driving transistor, the second driving unit includes a second driving transistor, the data writing unit includes a data writing transistor, the compensation unit includes a compensation transistor, the reset unit includes a reset transistor, the initialization unit includes a first initialization transistor and a second initialization transistor, the light emission control unit includes a first light emission control transistor, and the coupling module includes a coupling capacitor; the first electrode of the first light-emitting control transistor is connected with the first power line, the second electrode of the first light-emitting control transistor is connected with the first electrode of the second driving transistor, the second electrode of the second driving transistor is connected with the first end of the light-emitting module, the grid electrode of the first light-emitting control transistor is connected with the light-emitting control signal line, the grid electrodes of the first initializing transistor and the second initializing transistor are connected with the first scanning line, the first electrode of the first initializing transistor and the first electrode of the second initializing transistor are connected with the initializing signal line, the second electrode of the first initializing transistor is connected with the first end of the coupling capacitor, the second electrode of the second initializing transistor is connected with the second end of the coupling capacitor, the first end of the coupling capacitor is connected with the output end of the scanning driving circuit, the second end of the coupling capacitor is connected with the grid electrode of the first driving transistor, the compensating transistor is connected with the first end of the first scanning line, the first electrode of the compensating transistor is connected with the first end of the data writing transistor, the first electrode of the data writing transistor is connected with the first end of the data writing transistor.

According to another aspect of the present invention, there is provided a driving method of a display panel including a scan driving circuit and a plurality of rows of pixel driving circuits, an output terminal of the scan driving circuit being connected to the pixel driving circuits of a corresponding row, the pixel driving circuit including a coupling module, a driving module, and a light emitting module, the driving module and the light emitting module being connected between a first power line and a second power line, the coupling module being connected between an output terminal of the scan driving circuit and a control terminal of the driving module;

the driving method of the display panel comprises the following steps:

controlling the scanning driving circuit to transmit sweep frequency signals to the pixel driving circuits of the corresponding rows step by step, and controlling the driving module to control the light emitting time of the light emitting module according to the data voltage and the sweep frequency signals;

the sweep frequency signal is a continuously-changing voltage signal, and the voltage output by the scanning driving circuit is a step voltage associated with the sweep frequency signal.

According to another aspect of the present invention, there is provided a display device including the display panel provided by any of the embodiments of the present invention.

The technical scheme provided by the embodiment of the invention realizes the progressive scanning display effect of the pixel driving circuit by designing the sweep frequency signal into a progressive downloading mode so as to solve the problem of picture flicker. The display panel comprises a plurality of rows of pixel driving circuits, each pixel driving circuit comprises a coupling module, a driving module and a light emitting module, the driving modules and the light emitting modules are connected between a first power line and a second power line, the coupling modules are connected between the output end of the scanning driving circuit and the control end of the driving module, scanning driving circuits are adopted to transmit sweep signals to the pixel driving circuits in corresponding rows step by step, and the driving modules are used for controlling the light emitting time of the light emitting modules according to data voltages and the sweep signals, wherein the voltage output by the scanning driving circuits is a step voltage associated with the sweep signals. The technical scheme provided by the embodiment of the invention can realize progressive scanning display of the pixel driving circuit, can emit light after the pixel driving circuit completes writing of data voltage, controls the light emitting time of the light emitting module through the sweep frequency signal, does not need to wait for all pixel rows to complete writing of data and emit light together, and greatly reduces the non-light emitting time of pixels during the switching period of adjacent display frames, thereby being beneficial to improving the problem of flicker of display pictures. Accordingly, the increase of the light-emitting time is beneficial to the improvement of the maximum brightness of the light emission of the pixels and the gray scale development.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a display panel according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a pixel driving circuit according to an embodiment of the present invention;

FIG. 3 is a waveform diagram of an output voltage of a scan driving circuit according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of another display panel according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a scan driving circuit according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a structure of another pixel driving circuit according to an embodiment of the invention;

fig. 7 is a schematic diagram of a structure of another pixel driving circuit according to an embodiment of the invention;

fig. 8 is a timing control waveform diagram of a display panel according to an embodiment of the present invention;

fig. 9 is a schematic diagram of a structure of another pixel driving circuit according to an embodiment of the invention;

Fig. 10 is a schematic structural diagram of a display device according to an embodiment of the present invention.

Detailed Description

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

As described in the background art, when the conventional pixel driving circuit drives the light emitting element to emit light by using a digital driving method, a phenomenon of flicker of a picture is easy to occur, and the inventor has found that the reason for the occurrence of the above problem is as follows: when the conventional pixel driving circuit is driven by a digital driving method, the light emitting time is controlled by a sweet signal. The sweet signal is a global signal, and after the data signal is written, all pixel circuits in the whole display panel are uniformly switched into the sweet signal to be integrally pulled, so that the light emitting time of the light emitting device is controlled. Therefore, in the data signal writing process, the light emitting device needs to be controlled to be in a turned-off state, and the light emitting device can uniformly emit light after the data signal is completely written, so that the light emitting time of the light emitting device is influenced by the data signal writing time of the whole display panel, and the whole display panel is limited to be capable of displaying or turning off simultaneously. For large screens or higher PPI screen bodies, the time required for writing data of the whole display panel is longer, namely the time that the display panel does not emit light is longer, and the screen bodies are easy to flash in the picture switching process. In addition, in one frame, the data writing time is prolonged, so that the light emitting time is reduced, the highest brightness of the display panel is affected, and the display effect of the display panel is seriously reduced.

In view of the above problems, an embodiment of the present invention provides a display panel, which is configured to implement a progressive scanning display effect of a pixel driving circuit by designing a scanning signal to be in a progressive downloading manner, so as to improve the problem of flicker of a picture. The technical scheme provided by the invention is described in the following by a specific embodiment. Fig. 1 is a schematic structural diagram of a display panel according to an embodiment of the present invention, and fig. 2 is a schematic structural diagram of a pixel driving circuit according to an embodiment of the present invention, referring to fig. 1 and 2, the display panel 10 includes a scan driving circuit 210 and a plurality of rows of pixel driving circuits, an output end of the scan driving circuit 210 is connected to the pixel driving circuits of the corresponding rows, and the scan driving circuit 210 is configured to transmit a SWEEP signal sweet to the pixel driving circuits of the corresponding rows step by step;

the pixel driving circuit includes a coupling module 120, a driving module 110 and a light emitting module 130, wherein the driving module 110 and the light emitting module 130 are connected between a first power line L1 and a second power line L2, the coupling module 120 is connected between an output end of the scan driving circuit 210 and a control end N1 of the driving module 110, and the driving module 110 is configured to control a light emitting time of the light emitting module 130 according to the data voltage Vdata and the SWEEP signal sweet.

Specifically, the display panel 10 includes a plurality of pixel rows, each pixel includes at least three sub-pixel units, such as a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit, and the plurality of sub-pixel units are arranged in an array form inside the display panel 10. Each sub-pixel unit includes a pixel driving circuit 100, and the pixel driving circuit 100 is configured to drive the corresponding sub-pixel unit to emit light.

Here, the pixel driving circuit 100 may be a Pulse Width Modulation (PWM) pixel driving circuit of a digital driving system, or a pulse width modulation (PAM) pixel driving circuit of a digital-analog hybrid driving system. Each pixel driving circuit 100 controls the light emitting time of the sub-pixel unit according to the applied data voltage Vdata and the SWEEP signal sweet.

In the present embodiment, the pixel driving circuit 100 includes a driving module 110, a coupling module 120, and a light emitting module 130, wherein the light emitting module 130 includes light emitting elements corresponding to sub-pixel unit types. The driving module 110 and the light emitting module 130 are connected between the first power line L1 and the second power line L2, and the driving module 110 is configured to control on/off of a discharge path between the first power line L1 and the second power line L2 according to the data voltage Vdata and the SWEEP signal sweet, thereby controlling the light emitting time of the light emitting module 130. The first power line L1 may be used to transmit the first power voltage VDD, and the second power line L2 may be used to transmit the second power voltage VSS.

In this embodiment, the SWEEP signal sweet corresponding to each pixel row is provided by the scan driving circuit 210, and one output terminal of the scan driving circuit 210 may be correspondingly connected to one row of the pixel driving circuits 100. For example, the first output terminal of the scan driving circuit 210 is connected to the first row of pixel driving circuits for transmitting the first scan sub-signal S1 to the first row of pixel driving circuits, the second output terminal is connected to the second row of pixel driving circuits for transmitting the second scan sub-signal S2 … … to the second row of pixel driving circuits, and the nth output terminal is connected to the nth row of pixel driving circuits for transmitting the nth scan sub-signal Sn to the nth row of pixel driving circuits. In the light emitting stage, the scan driving circuit 210 transmits the voltage output from the output terminal thereof to the first terminal of the coupling module 120, and controls the voltage of the control terminal N1 of the driving module 110 under the coupling action of the coupling module 120, thereby controlling the light emitting time of the light emitting module 130.

The sweep frequency signal is a continuously varying voltage signal, and after the processing of the scan driving circuit 210, the voltage at the output end of the scan driving circuit 210 is a step voltage associated with the sweep frequency signal. Fig. 3 is a waveform diagram of an output voltage of a scan driving circuit according to an embodiment of the present invention, and with reference to fig. 3, a SWEEP signal sweet is transmitted to a pixel driving circuit 100 of a corresponding row step by step under the action of the scan driving circuit 210. For example, during the process of changing the SWEEP signal sweet, the first output terminal of the scan driving circuit 210 transmits the first voltage V1 of the SWEEP signal sweet to the first row of pixel driving circuits 100, that is, the first SWEEP sub-signal S1 corresponds to the first voltage V1 of the SWEEP signal sweet, and the first row of pixel driving circuits 100 drive the light emitting module 130 to emit light according to the data voltage Vdata and the first voltage V1 of the SWEEP signal sweet. The second scan sub-signal S2 outputted from the second output terminal of the scan driving circuit 210 maintains the low level of the scan signal sweet, so that the second row of pixels does not emit light. The scan driving circuit 210 then transmits the voltage at the first output terminal to the second output terminal, that is, the second scan sub-signal S2 corresponds to the first voltage V1 of the scan signal sweet at this time, and the second row of pixel driving circuits 100 drive the light emitting module 130 to emit light according to the data voltage Vdata and the first voltage V1 of the scan signal sweet at this time. Along with the gradual change of the SWEEP signal sweet, the scan driving circuit 210 transmits the second voltage V2 of the SWEEP signal sweet to the first output terminal thereof, and at this time, the first SWEEP sub-signal S1 corresponds to the second voltage V1 of the SWEEP signal sweet, that is, the input voltage corresponding to the first row of pixels changes, and the coupling module 120 controls the voltage of the control terminal N1 of the driving module 110 according to the voltage change amount of the first terminal thereof, so as to control the light emitting time of the light emitting module 130. Then, the voltage of the third scanning sub-signal S2 output from the third output terminal of the scanning driving circuit 210 jumps to the first voltage V1 of the scanning signal sweet, the third row of pixels emits light, and so on, the scanning driving circuit 210 transfers the voltage of the scanning signal sweet step by step down until the last row of pixels emits light. Thereby realizing the function of progressive scanning display.

Of course, in other embodiments, an output end of the scan driving circuit 210 may be connected to the multi-line scan driving circuit 100 at the same time, so as to realize multi-line pixel simultaneous scan display, which is not described herein.

The display panel provided by the embodiment of the invention comprises a plurality of rows of pixel driving circuits, wherein each pixel driving circuit comprises a coupling module, a driving module and a light emitting module, the driving module and the light emitting module are connected between a first power line and a second power line, the coupling module is connected between the output end of a scanning driving circuit and the control end of the driving module, the scanning driving circuit is adopted to transmit sweep signals to the pixel driving circuits of corresponding rows step by step, and the driving module is used for controlling the light emitting time of the light emitting module according to data voltage and the sweep signals, wherein the voltage output by the scanning driving circuit is a step voltage associated with the sweep signals. The technical scheme provided by the embodiment of the invention can realize progressive scanning display of the pixel driving circuit, can emit light after the pixel driving circuit completes writing of data voltage, controls the light emitting time of the light emitting module through the sweep frequency signal, does not need to wait for all pixel rows to complete writing of data and emit light together, and greatly reduces the non-light emitting time of pixels during the switching period of adjacent display frames, thereby being beneficial to improving the problem of flicker of display pictures. Accordingly, the increase of the light-emitting time is beneficial to the improvement of the maximum brightness of the light emission of the pixels and the gray scale development.

Fig. 4 is a schematic structural diagram of another display panel according to an embodiment of the present invention, referring to fig. 4, optionally, the scan driving circuit 210 includes an n-stage signal transmission module 211, an output end of the upper stage signal transmission module 211 is connected to an input end of the lower stage signal transmission module 212, wherein the input end of the first stage signal transmission module 211 is connected to a SWEEP signal sweet; the output end of each stage of signal transmission module 211 is used as an output end of the scanning driving circuit 210 and is connected with the corresponding pixel driving circuit 100; where n is the number of rows of the pixel driving circuit 100.

Specifically, the scan driving circuit 210 may include multiple stages of signal transmission modules 211, wherein an output end of each stage of signal transmission module 211 is correspondingly connected to a row of pixel driving circuits corresponding to an output end of a scan driving circuit 210, and a voltage of an output end of a previous stage of signal transmission module 211 is used as an input of a next stage of signal transmission module 211. The control end of the odd-numbered stage signal transmission module 211 is connected to the first clock signal line, and the control end of the even-numbered stage signal transmission module 211 is connected to the second clock signal line. The first clock signal line is used for transmitting a first clock signal CK1, the second clock signal line is used for transmitting a second clock signal CK2, the first clock signal CK1 and the second clock signal CK2 are complementary signals, that is, when the odd-numbered stage signal transmission module 211 is turned on, the even-numbered stage signal transmission module 211 is turned off, so that voltage step-by-step transmission corresponding to the SWEEP frequency signal sweet is realized.

Illustratively, in conjunction with fig. 3, the SWEEP signal sweet is maintained at a low level prior to the light-emitting phase. After entering the light-emitting stage, the first row of pixels are controlled to emit light, and meanwhile, the SWEEP frequency signal SWEEP gradually changes to a high level. When the first clock signal CK1 controls the odd-numbered stage signal transmission module 211 to be turned on, the first voltage V1 of the SWEEP signal sweet is written into the first-stage signal transmission module 211, and the first-stage signal transmission module 211 outputs the first-row pixel driving circuit 100, i.e. the voltage of the first SWEEP sub-signal S1 is the first voltage V1 of the SWEEP signal sweet, and the voltage of the control terminal of the driving module 110 corresponding to the first-row pixel driving circuit is pulled up.

The second row pixel driving circuit writes the data voltage Vdata to control the second row pixels to emit light. The second clock signal CK2 controls the even-numbered stage signal transmission modules 211 to be turned on, the first voltage V1 of the SWEEP signal sweet at the output end of the first-stage signal transmission module 211 is written into the second-stage signal transmission module 211, and the second-stage signal transmission module 211 outputs the first voltage V1 of the SWEEP signal sweet, that is, the voltage of the second SWEEP sub-signal S2 is the first voltage V1 of the SWEEP signal sweet, and the voltage of the control end of the driving module 110 corresponding to the second-row pixel driving circuit is pulled up.

The third row pixel driving circuit writes the data voltage Vdata to control the third row pixels to emit light. When the first clock signal CK1 controls the odd-numbered stage signal transmission module 211 to be turned on again, the second voltage V2 of the SWEEP frequency signal sweet is written into the first stage signal transmission module 211, the first SWEEP frequency sub-signal S1 output by the first stage signal transmission module 211 jumps to the second voltage V2 of the SWEEP frequency signal sweet, and the control terminal voltage of the driving module 110 corresponding to the first row of pixel driving circuits is further pulled up under the action of the coupling module 120. Meanwhile, the voltage at the output end of the second-stage signal transmission module 211 is transmitted to the third-stage signal transmission module 211, the third-stage signal transmission module 211 transmits the first voltage V1 of the SWEEP frequency signal sweet to the third row of pixel driving circuits, and the voltage of the control end of the driving module 110 corresponding to the third row of pixel driving circuits is raised.

When the second clock signal CK2 controls the even-numbered stage signal transmission module 211 to be turned on again, the second row of pixel driving circuits 100 writes the second voltage V2 of the SWEEP signal sweet, and the fourth row of pixel circuits 100 writes the first voltage V1 of the SWEEP signal sweet, and so on. When the voltage at the control terminal N1 of the driving module 110 of the first row pixel driving circuit turns off the driving module 110, the first row pixels stop emitting light, and then the second row pixels stop emitting light until the last row of pixels are turned off, and the light emission is ended.

Note that, the data voltage Vdata and the SWEEP signal sweet are written into the pixel driving circuit row by row, so that the pixel progressive scanning display function can be realized.

Fig. 5 is a schematic structural diagram of a scan driving circuit according to an embodiment of the present invention, referring to fig. 5, based on the above technical solution, optionally, the signal transmission module 211 includes a switch unit 201 and a storage unit 202, a first end of the switch unit 201 is used as an input end of the signal transmission module 211, a second end of the switch unit 201 is used as an output end of the signal transmission module 211, a control end of the switch unit 201 is used as a control end of the signal transmission module 211, and the storage unit 202 is connected between the first end and the second end of the switch unit 201.

The switch unit 201 is configured to turn on or off the signal transmission module 211 according to a corresponding clock signal, and the storage unit 202 is configured to store the voltage output by the switch unit 201. Specifically, the switch unit 201 includes switch transistors (e.g., MK1, MK2 … … MKn), and the memory unit 202 includes memory capacitors (e.g., C1, C2 … … Cn), where the memory capacitors may be the same or different, and the embodiment is not limited in any way. When the first stage signal transmission module 211 is turned on, the first voltage V1 of the SWEEP signal sweet is transmitted to the first end of the coupling module 120 of the first row pixel driving circuit through the switching transistor MK1 and stored on the storage capacitor C1. When the second-stage signal transmission module 211 is turned on, the first voltage V1 of the SWEEP signal sweet stored on the storage capacitor C1 is transmitted to the first terminal of the coupling module 120 of the second row pixel driving circuit through the switching transistor MK2 and stored on the storage capacitor C2. When the first stage signal transmission module 211 is turned on again, the second voltage V2 of the SWEEP signal sweet is transmitted to the first terminal of the coupling module 120 of the first row pixel driving circuit through the switching transistor MK1 and stored on the storage capacitor C1. Since the first-stage signal transmission module 211 and the third-stage signal transmission module 211 are connected to the same clock signal, the third-stage signal transmission module 211 is turned on, the first voltage V1 of the SWEEP signal sweet stored in the storage capacitor C2 is transmitted to the first end of the coupling module 120 of the third row pixel driving circuit through the switching transistor MK3, and the storage capacitor C3 is stored in … … until the last row pixel driving circuit writes the SWEEP signal sweet. Thereby realizing that the SWEEP frequency signal sweet is transferred to the corresponding pixel row step by step according to the sequence of the first voltage V1, the second voltage V2 … … and the mth voltage Vm.

Fig. 6 is a schematic structural diagram of another pixel driving circuit according to an embodiment of the present invention, referring to fig. 5 and 6, based on the above technical solutions, the driving module 110 includes a data writing unit 102, a first driving unit 101, an initializing unit 103, and a light emitting control unit 104, the light emitting control unit 104 and the first driving unit 101 are connected between a first power line L1 and a first end of the light emitting module 130, a second end of the light emitting module 130 is connected to a second power line L2, the data writing unit 102 is used for writing a data voltage Vdata to a control end of the first driving unit 101 in a data writing stage, the initializing unit 103 is used for transmitting an initializing voltage Vinit to a first end and a second end of the coupling module 120 in an initializing stage, the first end of the coupling module 120 is connected to an output end of the scan driving circuit 210, and the second end of the coupling module 120 is connected to a control end of the first driving unit 101.

The initializing unit 103 is configured to initialize the potentials of the first end and the second end of the coupling module 120 in an initializing stage, the data writing unit 102 is configured to write the data voltage Vdata to the control end of the first driving unit 101 in a data writing stage, and the light emission control unit 104 is configured to control the discharge path of the light emitting module 130 to be turned on in a light emitting stage, so as to control the light emitting module 130 to emit light.

Fig. 7 is a schematic structural diagram of another pixel driving circuit according to an embodiment of the present invention, preferably, the driving module 110 further includes a compensation unit 105, and the compensation unit 105 is connected between the second end and the control end of the first driving unit 101 to improve the accuracy of converting the data voltage Vdata into the time control signal, thereby realizing accurate control of the light emitting time of the light emitting module 130. The data writing unit 102 is connected between the data line and the first terminal of the first driving unit 101.

Specifically, the coupling module 120 includes a coupling capacitance Ci, the first driving unit 101 includes a first driving transistor M1, the data writing unit 102 includes a data writing transistor M2, the compensation unit 105 includes a compensation transistor M3, the initialization unit 103 includes a first initialization transistor M41 and a second initialization transistor M42, and the light emission control unit 104 includes a first light emission control transistor M51 and a second light emission control transistor M52; a first pole of the first light emitting control transistor M51 is connected to the first power line L1, a second pole of the first light emitting control transistor M51 is connected to a first pole of the first driving transistor M1, a second pole of the first driving transistor M1 is connected to a first end of the light emitting module 130 through the second light emitting control transistor M52, and a gate of the first light emitting control transistor M51 and a gate of the second light emitting control transistor M52 are both connected to the light emitting control signal line EM; the gates of the first initialization transistor M41 and the second initialization transistor M42 are connected to the first scan line G1, the first pole of the first initialization transistor M41 and the first pole of the second initialization transistor M42 are connected to the initialization signal line, the second pole of the first initialization transistor M41 is connected to the first end of the coupling capacitor Ci, the second pole of the second initialization transistor M42 is connected to the second end of the coupling capacitor Ci, the first end of the coupling capacitor Ci is connected to the output end of the scan driving circuit 210, the second end of the coupling capacitor Ci is connected to the gate of the first driving transistor M1, the compensation transistor M3 is connected between the second pole and the gate of the first driving transistor M1, and the gate of the compensation transistor M3 and the gate of the data writing transistor M2 are connected to the second scan line G2; the first pole of the data writing transistor M2 is connected to the data line, and the second pole of the data writing transistor M2 is connected to the first pole of the first driving transistor M1.

For convenience of description, the scan lines and the scan signals output by the scan lines are denoted by the same reference numerals in this embodiment, and the following description is omitted.

Fig. 8 is a timing control waveform diagram of a display panel according to an embodiment of the present invention, which is applicable to the pixel driving circuit shown in fig. 7, and only a P-channel transistor is used as an example for illustration, and in other embodiments, each transistor may be an N-channel transistor. Referring to fig. 8, the working process of the pixel driving circuit provided in the embodiment of the invention at least includes an initialization phase T1, a data writing phase T2 and a light emitting phase T3.

In the initialization stage T1, the first scan line is configured to transmit the first scan signal G1 of a low level, the second scan line is configured to transmit the second scan signal G2 of a high level, the emission control signal line is configured to transmit the emission control signal EM of a high level, and the SWEEP signal sweet maintains a low level. The first initializing transistor M41 and the second initializing transistor M42 are turned on, and transmit the initializing voltage Vinit transmitted on the initializing signal line to the first end and the second end of the coupling capacitor Ci, so as to initialize the potential of the coupling capacitor Ci, and prevent the residual charge of the previous display frame from affecting the current display frame. At this time, the first driving transistor M1 is in an on state.

In the data writing stage T2, the first scan line is configured to transmit the first scan signal G1 of a high level, the second scan line is configured to transmit the second scan signal G2 of a low level, the emission control signal line is configured to transmit the emission control signal EM of a high level, and the SWEEP signal sweet maintains a low level. The data writing transistor M2 and the compensating transistor M3 are turned on, the data voltage Vdata charges the gate of the first driving transistor M1 through the data writing transistor M2, the first driving transistor M1 and the compensating transistor M3, and when the gate voltage of the first driving transistor M1 is vdata+vth1, the first driving transistor M1 is turned off to implement threshold compensation for the first driving transistor M1. Wherein Vth1 is the threshold voltage of the first driving transistor M1. The first terminal of the coupling capacitor Ci maintains a low level of the SWEEP signal sweet.

In the light emitting stage T3, the first scan line is configured to transmit the first scan signal G1 of a high level, the second scan line is configured to transmit the second scan signal G2 of a high level, the light emitting control signal line is configured to transmit the light emitting control signal EM of a low level, and the SWEEP signal sweet is gradually changed from the low level to the high level. The first and second light emission control transistors M51 and M52 are turned on, the discharge path between the first and second power lines L1 and L2 is turned on, and the light emitting module 130 emits light under the first and second power voltages VDD and VSS. Meanwhile, the SWEEP frequency signal sweet is written into the first end of the coupling capacitor Ci through the scan driving circuit 210, the gate voltage of the first driving transistor M1 is gradually pulled up under the coupling action of the coupling capacitor Ci, and when the gate voltage thereof turns off the first driving transistor M1, the light emitting module 130 is turned off.

It should be appreciated that the above-described process is an operation of the one-row pixel driving circuit 100. The working process of each row of pixel driving circuit 100 includes the above steps, and the SWEEP driving circuit 210 transmits the voltage corresponding to the SWEEP signal sweet to the pixel driving circuit 100 in the corresponding row by row, so that the pixel light emitting process in the row by row can be realized, and the detailed description can refer to the related description of the SWEEP driving circuit 210, which is not repeated here.

Fig. 9 is a schematic structural diagram of another pixel driving circuit according to an embodiment of the present invention, referring to fig. 5 and 9, the driving module 110 includes a data writing unit 102, a first driving unit 101, a second driving unit 107, a compensating unit 105, an initializing unit 103, a resetting unit 106, and a light emitting control unit 104, where the data writing unit 102 is connected between a data line and a first end of the coupling module 120, a second end of the coupling module 120 is connected to a control end of the first driving unit 101, the first driving unit 101 is connected between a control end of the first power line L1 and a control end of the second driving unit 107, the second driving unit 107 and the light emitting control unit 104 are connected between the first power line L1 and a first end of the light emitting module 130, and a second end of the light emitting module 130 is connected to the second power line L2; the compensation unit 105 is connected between the second terminal and the control terminal of the first driving unit 101, the reset unit 106 is configured to transmit an initialization voltage Vinit to the control terminal of the second driving unit 107 during a reset phase, and the initialization unit 103 is configured to transmit the initialization voltage Vinit to the first terminal and the second terminal of the coupling module 120 during an initialization phase.

Specifically, the first driving unit 101 includes a first driving transistor M1, the second driving unit 107 includes a second driving transistor M2, the data writing unit 102 includes a data writing transistor M2, the compensation unit 105 includes a compensation transistor M3, the reset unit 106 includes a reset transistor M6, the initializing unit 103 includes a first initializing transistor M41 and a second initializing transistor M42, the light emission control unit 104 includes a first light emission control transistor M51, and the coupling module 120 includes a coupling capacitor Ci; the first pole of the first light emitting control transistor M51 is connected to the first power line L1, the second pole of the first light emitting control transistor M51 is connected to the first pole of the second driving transistor M7, the second pole of the second driving transistor M7 is connected to the first end of the light emitting module 130, the gate of the first light emitting control transistor M51 is connected to the light emitting control signal line EM, the gates of the first initializing transistor M41 and the second initializing transistor M42 are both connected to the first scanning line G1, the first pole of the first initializing transistor M41 and the first pole of the second initializing transistor M42 are both connected to the initializing signal line, the second pole of the first initializing transistor M41 is connected to the first end of the coupling capacitor Ci, the first end of the coupling capacitor Ci is connected to the output end of the scanning driving circuit 210, the second end of the coupling capacitor Ci is connected to the gate of the first driving transistor M1, the compensating transistor M3 is connected to the first end of the first scanning line M1 and the first end of the first diode M2, the data writing transistor M2 is connected to the first end of the first scanning line G2, and the data writing transistor M2 is connected to the gate of the first writing transistor M2.

The structure of the pixel driving circuit shown in fig. 9 is different from the pixel driving circuit shown in fig. 7 in that the data writing unit 102 in the pixel driving circuit shown in fig. 9 is connected to the first end of the coupling module 120, the data voltage Vdata is coupled to the gate of the first driving transistor M1 through the coupling capacitor Ci, in the data writing stage, the voltage at the first end of the coupling capacitor Ci is Vdata, and the voltage at the second end is vdd+vth1, so that the magnitude of the first power supply voltage VDD does not need to be set according to the magnitude of the data voltage Vdata, and flexibility of the first power supply voltage VDD is increased. In addition, the driving module 110 further includes a second driving unit 107, and the reset unit 106 transmits the initialization voltage Vinit to the gate of the second driving transistor M7 during the reset phase to turn on the second driving transistor M7. In the light emitting stage, the first light emitting control transistor M51 is controlled to be turned on, and the light emitting module 130 emits light. With the gradual change of the SWEEP signal sweet (here, the SWEEP signal sweet changes from high level to low level), the gate voltage of the first driving transistor M1 changes synchronously under the action of the coupling capacitor Ci, when the first driving transistor M1 is turned on according to the gate voltage thereof, the first power voltage VDD is transmitted to the gate of the second driving transistor M7, and the second driving transistor M7 is controlled to be turned off, so as to control the light emitting module 130 to be turned off, and control the light emitting time of the light emitting module 130 is realized. The operation of the remaining modules/units is the same as that of the circuit shown in fig. 7, and will not be described again here.

Of course, in other embodiments, the second driving unit 107 may include an analog driving circuit, and the light emitting time of the light emitting module 130 is controlled by an analog-digital hybrid driving method, which is also applicable to the scan driving circuit 210 provided in the embodiments of the present invention.

In this embodiment, the light emitting module 130 may include LED, OLED, micro-LEDs or Mini LEDs, etc.

Optionally, as shown in fig. 1 and fig. 2, the display panel 10 includes a scan driving circuit 210 and a plurality of rows of pixel driving circuits 100, an output end of the scan driving circuit 210 is connected to the pixel driving circuits 100 of the corresponding row, the pixel driving circuit 100 includes a coupling module 120, a driving module 110 and a light emitting module 130, the driving module 110 and the light emitting module 130 are connected between a first power line L1 and a second power line L2, and the coupling module 120 is connected between an output end of the scan driving circuit 210 and a control end N1 of the driving module 110. The method comprises the following steps:

and controlling the scanning driving circuit to transmit sweep frequency signals to the pixel driving circuits of the corresponding rows step by step, and controlling the driving module to control the light emitting time of the light emitting module according to the data voltage and the sweep frequency signals.

The sweep frequency signal is a continuously-changing voltage signal, and the voltage output by the scanning driving circuit is a step voltage associated with the sweep frequency signal.

The driving method of the display panel provided by the embodiment of the invention is suitable for the display panel provided by any embodiment, the display panel comprises a plurality of rows of pixel driving circuits, each pixel driving circuit comprises a coupling module, a driving module and a light emitting module, the driving module and the light emitting module are connected between a first power line and a second power line, the coupling module is connected between the output end of the scanning driving circuit and the control end of the driving module, the scanning driving circuit is adopted to transmit sweep signals to the pixel driving circuits of the corresponding rows step by step, and the driving module is used for controlling the light emitting time of the light emitting module according to data voltage and the sweep signals, wherein the voltage output by the scanning driving circuit is a step voltage related to the sweep signals. The technical scheme provided by the embodiment of the invention can realize progressive scanning display of the pixel driving circuit, can emit light after the pixel driving circuit completes writing of data voltage, controls the light emitting time of the light emitting module through the sweep frequency signal, does not need to wait for all pixel rows to complete writing of data and emit light together, and greatly reduces the non-light emitting time of pixels during the switching period of adjacent display frames, thereby being beneficial to improving the problem of flicker of display pictures. Accordingly, the increase of the light-emitting time is beneficial to the improvement of the maximum brightness of the light emission of the pixels and the gray scale development.

Optionally, the embodiment of the present invention further provides a display device, where the display device includes the display panel provided by the embodiment of the present invention, fig. 10 is a schematic structural diagram of the display device provided by the embodiment of the present invention, where the display device may be a mobile phone shown in fig. 10, or may be a tablet, an electronic watch, a wearable device, or all other display-related electronic products such as a vehicle-mounted display, a camera display, a television, and a computer screen. The display device provided by the embodiment of the invention also has the beneficial effects described in any embodiment of the invention because the display device comprises the display panel provided by any embodiment of the invention.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present invention may be performed in parallel, sequentially, or in a different order, so long as the desired results of the technical solution of the present invention are achieved, and the present invention is not limited herein.

The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims (10)

1. The display panel is characterized by comprising a scanning driving circuit and a plurality of rows of pixel driving circuits, wherein one output end of the scanning driving circuit is connected with the pixel driving circuits of the corresponding rows, and the scanning driving circuit is used for transmitting sweep frequency signals to the pixel driving circuits of the corresponding rows step by step;

the pixel driving circuit comprises a coupling module, a driving module and a light emitting module, wherein the driving module and the light emitting module are connected between a first power line and a second power line, the coupling module is connected between the output end of the scanning driving circuit and the control end of the driving module, and the driving module is used for controlling the light emitting time of the light emitting module according to data voltage and the sweep frequency signal;

the sweep frequency signal is a continuously-changing voltage signal, and the voltage output by the scanning driving circuit is a step voltage associated with the sweep frequency signal.

2. The display panel of claim 1, wherein each output of the scan driving circuit is correspondingly connected to a first end of the coupling module of a row of the pixel driving circuits, a second end of the coupling module is connected to a control end of the driving module, and the scan driving circuit is configured to transmit the sweep signal to the first end of the coupling module row by row in a light emitting stage.

3. The display panel according to claim 1, wherein the scan driving circuit comprises n-stage signal transmission modules, an output end of a signal transmission module of a previous stage is connected with an input end of a signal transmission module of a next stage, and an input end of the signal transmission module of a first stage is connected with the sweep frequency signal; the output end of each stage of signal transmission module is used as an output end of the scanning driving circuit and is connected with the corresponding pixel driving circuit; wherein n is the number of rows of the pixel driving circuit.

4. A display panel according to claim 3, wherein the control terminal of the signal transmission module of the odd-numbered stage is connected to a first clock signal line, and the control terminal of the signal transmission module of the even-numbered stage is connected to a second clock signal line;

the first clock signal transmitted on the first clock signal line and the second clock signal transmitted on the second clock signal line are complementary signals.

5. The display panel according to claim 4, wherein the signal transmission module includes a switching unit having a first end as an input end of the signal transmission module, a second end as an output end of the signal transmission module, a control end as a control end of the signal transmission module, and a storage unit connected between the first and second ends of the switching unit;

Preferably, the switching unit includes a switching transistor, and the memory unit includes a storage capacitor.

6. The display panel according to claim 1, wherein the driving module includes a data writing unit, a first driving unit, an initializing unit, and a light emission control unit, the light emission control unit and the first driving unit are connected between the first power line and a first end of the light emitting module, a second end of the light emitting module is connected to the second power line, the data writing unit is used for writing the data voltage to a control end of the first driving unit during a data writing stage, the initializing unit is used for transmitting an initializing voltage to a first end and a second end of the coupling module during an initializing stage, the first end of the coupling module is connected to an output end of the scan driving circuit, and the second end of the coupling module is connected to a control end of the first driving unit;

preferably, the driving module further includes a compensation unit connected between the second end and the control end of the first driving unit, and the data writing unit is connected between the data line and the first end of the first driving unit.

7. The display panel according to claim 6, wherein the coupling module includes a coupling capacitance, the first driving unit includes a first driving transistor, the data writing unit includes a data writing transistor, the compensating unit includes a compensating transistor, the initializing unit includes a first initializing transistor and a second initializing transistor, and the light emission control unit includes a first light emission control transistor and a second light emission control transistor;

the first electrode of the first light-emitting control transistor is connected with the first power line, the second electrode of the first light-emitting control transistor is connected with the first electrode of the first driving transistor, the second electrode of the first driving transistor is connected with the first end of the light-emitting module through the second light-emitting control transistor, and the grid electrode of the first light-emitting control transistor and the grid electrode of the second light-emitting control transistor are both connected with a light-emitting control signal line; the first electrode of the first initializing transistor and the first electrode of the second initializing transistor are connected with an initializing signal line, the second electrode of the first initializing transistor is connected with the first end of the coupling capacitor, the second electrode of the second initializing transistor is connected with the second end of the coupling capacitor, the first end of the coupling capacitor is connected with the output end of the scanning driving circuit, the second end of the coupling capacitor is connected with the gate of the first driving transistor, the compensating transistor is connected between the second electrode and the gate of the first driving transistor, and the gate of the compensating transistor and the gate of the data writing transistor are connected with the second scanning line;

The first pole of the data writing transistor is connected with the data line, and the second pole of the data writing transistor is connected with the first pole of the first driving transistor.

8. The display panel according to claim 1, wherein the driving module includes a data writing unit, a first driving unit, a second driving unit, a compensation unit, an initializing unit, a resetting unit, and a light emitting control unit, the data writing unit is connected between a data line and a first end of the coupling module, a second end of the coupling module is connected to a control end of the first driving unit, the first driving unit is connected between the first power line and a control end of the second driving unit, the second driving unit and the light emitting control unit are connected between the first power line and a first end of the light emitting module, and a second end of the light emitting module is connected to the second power line;

the compensation unit is connected between the second end and the control end of the first driving unit, the reset unit is used for transmitting an initialization voltage to the control end of the second driving unit in a reset stage, and the initialization unit is used for transmitting the initialization voltage to the first end and the second end of the coupling module in the initialization stage;

Preferably, the first driving unit includes a first driving transistor, the second driving unit includes a second driving transistor, the data writing unit includes a data writing transistor, the compensation unit includes a compensation transistor, the reset unit includes a reset transistor, the initialization unit includes a first initialization transistor and a second initialization transistor, the light emission control unit includes a first light emission control transistor, and the coupling module includes a coupling capacitor; the first electrode of the first light-emitting control transistor is connected with the first power line, the second electrode of the first light-emitting control transistor is connected with the first electrode of the second driving transistor, the second electrode of the second driving transistor is connected with the first end of the light-emitting module, the grid electrode of the first light-emitting control transistor is connected with the light-emitting control signal line, the grid electrodes of the first initializing transistor and the second initializing transistor are connected with the first scanning line, the first electrode of the first initializing transistor and the first electrode of the second initializing transistor are connected with the initializing signal line, the second electrode of the first initializing transistor is connected with the first end of the coupling capacitor, the second electrode of the second initializing transistor is connected with the second end of the coupling capacitor, the first end of the coupling capacitor is connected with the output end of the scanning driving circuit, the second end of the coupling capacitor is connected with the grid electrode of the first driving transistor, the compensating transistor is connected with the first end of the first scanning line, the first electrode of the compensating transistor is connected with the first end of the data writing transistor, the first electrode of the data writing transistor is connected with the first end of the data writing transistor.

9. The driving method of the display panel is characterized in that the display panel comprises a scanning driving circuit and a plurality of rows of pixel driving circuits, one output end of the scanning driving circuit is connected with the pixel driving circuits of the corresponding rows, the pixel driving circuit comprises a coupling module, a driving module and a light emitting module, the driving module and the light emitting module are connected between a first power line and a second power line, and the coupling module is connected between the output end of the scanning driving circuit and a control end of the driving module;

the driving method of the display panel comprises the following steps:

controlling the scanning driving circuit to transmit sweep frequency signals to the pixel driving circuits of the corresponding rows step by step, and controlling the driving module to control the light emitting time of the light emitting module according to the data voltage and the sweep frequency signals;

the sweep frequency signal is a continuously-changing voltage signal, and the voltage output by the scanning driving circuit is a step voltage associated with the sweep frequency signal.

10. A display device comprising the display panel according to any one of claims 1-8.