Pixel driving circuit and driving method thereof, and display device

Abstract

The present invention discloses a pixel driving circuit and a driving method thereof, and a display device, and relates to the field of display technology. The pixel driving circuit comprises a first power signal terminal, a second power signal terminal, a driving transistor, a light-emitting element, a first reset module, and a second reset module. The embodiment provided by the present invention can enhance the reset capability of the pixel driving circuit, while reducing signal lines, reducing power consumption, and increasing the penetration rate of the display panel.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and more specifically, to a pixel driving circuit and a driving method thereof, and a display device. Background Art

[0002] Display devices such as liquid crystal display (LCD) and organic light emitting diode display (OLED) include a plurality of pixel units arranged in an array, and each pixel unit generally includes at least three sub-pixels of red, green and blue. The different luminous intensities of the sub-pixels of the three colors, namely red, green and blue, form different colors to display the picture.

[0003] In the related art, in order to improve the display effect of the display panel, a reset signal is introduced into the pixel driving circuit. The Cst capacitor and the anode capacitor in the pixel driving circuit are reset before driving. At present, there are two common reset signal designs. One is a single reset signal, and one signal line resets the Cst capacitor and the anode capacitor at the same time. However, the load of the reset signal is heavy and the reset effect is not good; the other is a double reset signal, one signal line resets the Cst capacitor, and one signal line resets the anode capacitor, but an additional signal line is required, which increases power consumption and reduces the display panel penetration. Summary of the invention

[0004] In view of this, the present invention provides a pixel driving circuit and a driving method thereof, and a display device, which can enhance the reset capability of the pixel driving circuit, while reducing signal lines, lowering power consumption, and increasing the display panel penetration rate.

[0005] In a first aspect, the present invention provides a pixel driving circuit, comprising a first power signal terminal and a second power signal terminal, wherein the first power signal terminal is used to receive a first voltage signal, and the second power signal terminal is used to receive a second voltage signal;

[0006] A driving transistor, wherein a gate of the driving transistor is connected to a first node, a first electrode of the driving transistor is connected to the first power signal terminal, and a second electrode of the driving transistor is connected to a second node; the driving transistor is used to provide a driving current in a light emitting stage;

[0007] A light emitting element, wherein a first end of the light emitting element is connected to the second node, and a second end of the light emitting element is connected to the second power signal end; the light emitting element is used to respond to the driving current and emit light in a light emitting stage;

[0008] A first reset module, wherein the first reset module is connected between the second reset signal terminal and the first node, and the control terminal of the first reset module is connected to the first reset signal terminal; the first reset module is used to reset the first node in an initialization phase;

[0009] The second reset module is connected between the first reset signal terminal and the second node, and the control terminal of the second reset module is connected to the second reset signal terminal; the second reset module is used to reset the second node in the initialization stage.

[0010] In a second aspect, the present invention provides a pixel driving method for driving the pixel driving circuit provided in the first aspect of the present invention, wherein the pixel driving circuit comprises: a driving transistor, a light emitting element, a power supply voltage writing module, a data writing module, a compensation module, a light emitting control module, a first reset module and a second reset module;

[0011] Characterized in that the driving method comprises:

[0012] Initialization phase, data writing phase and light emitting phase;

[0013] The initialization phase includes a first initialization phase and a second initialization phase;

[0014] In the first initialization stage, the first reset module is turned on, and the second reset signal at the second reset signal end is transmitted to the first node through the first reset module to reset the first node;

[0015] In the second initialization stage, the second reset module is turned on, and the first reset signal at the first reset signal end is transmitted to the second node through the second reset module to reset the second node;

[0016] In the data writing stage, the data writing module and the compensation module are turned on; the data signal at the data signal end is transmitted to the first node through the data writing module, the driving transistor and the compensation module;

[0017] In the light-emitting stage, the power supply voltage writing module and the light-emitting control module are turned on; the first voltage signal at the first power supply signal end is transmitted to the first electrode of the driving transistor through the power supply voltage writing module, and the driving transistor is driven to form a current which is transmitted to the light-emitting element through the light-emitting control module;

[0018] The data writing phase is included in the second initialization phase.

[0019] In a third aspect, the present invention provides a display device, comprising the pixel driving circuit provided in the first aspect of the present invention.

[0020] Compared with the prior art, the pixel driving circuit and driving method thereof, and the display device provided by the present invention achieve at least the following beneficial effects:

[0021] The embodiment provided by the present invention, by setting two reset modules, namely the first reset module and the second reset module, respectively resets the first node and the second node of the pixel driving circuit, and can clear the residual voltage of the first node and the second node in the last light emission, so as to make the light-emitting element emit light according to the preset brightness, thus helping to improve the accuracy of the light-emitting brightness of the light-emitting element. In addition, the embodiment provided by the present invention includes two reset signal terminals, namely the first reset signal terminal and the second reset signal terminal, and the first reset signal terminal and the second reset signal terminal provide reset signals for the second node and the first node respectively. It avoids the technical problem that one reset signal line resets two nodes at the same time, resulting in an overload of the reset signal line. In addition, the first reset signal provided by the first reset signal terminal and the second reset signal provided by the second signal terminal are respectively the control terminal signal and the input terminal signal of the first reset module and the second reset module, saving a special control terminal signal line, reducing the power consumption of the pixel driving circuit, and improving the transmittance of the display panel.

[0022] Of course, any product implementing the present invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0023] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0025] Figure 1 A layout of a pixel driving circuit in the related art;

[0026] Figure 2 is a layout of another pixel driving circuit in the related art;

[0027] Figure 3 A schematic structural diagram of a pixel driving circuit provided by an embodiment of the present invention;

[0028] Figure 4 A layout of a pixel driving circuit provided by an embodiment of the present invention;

[0029] Figure 5 A schematic diagram of the structure of another pixel driving circuit provided by an embodiment of the present invention;

[0030] Figure 6A schematic diagram of the structure of another pixel driving circuit provided by an embodiment of the present invention;

[0031] Figure 7 A schematic diagram of the structure of another pixel driving circuit provided by an embodiment of the present invention;

[0032] Figure 8 A schematic diagram of the structure of another pixel driving circuit provided by an embodiment of the present invention;

[0033] Fig. 9 A timing diagram of a pixel driving method provided by an embodiment of the present invention;

[0034] Fig.10 A flowchart of a pixel driving method provided by an embodiment of the present invention;

[0035] Fig.11 A top view of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0037] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0038] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0039] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0040] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0041] In the related art, in order to improve the display effect of the display panel, a reset signal is introduced into the pixel driving circuit. The Cst capacitor and the anode capacitor in the pixel driving circuit are reset before driving. There are currently two common reset signal designs. Figure 1 As shown, Figure 1 The present invention is a layout of a pixel driving circuit in the related art. Figure 1The pixel driving circuit shown includes a reset signal line, and the signal line resets the Cst capacitor and the anode capacitor at the same time. However, the reset signal load is heavy and the reset effect is poor. Figure 2 As shown, Figure 2 This is a layout of another pixel driving circuit in the related art. Figure 2 The pixel driving circuit shown includes two reset signal lines, one signal line resets the Cst capacitor, and one signal line resets the anode capacitor, but an additional signal line is required, which increases power consumption and reduces the display panel transmittance.

[0042] In order to solve the above technical problems, an embodiment of the present invention provides a pixel driving circuit, referring to Figure 3 and Figure 4 As shown, Figure 3 A schematic diagram of the structure of a pixel driving circuit provided by an embodiment of the present invention is shown in FIG. Figure 4 Schematic diagram of a pixel driving circuit provided in an embodiment of the present invention. An embodiment of the present invention provides a pixel driving circuit 100, including:

[0043] A first power signal terminal PVDD and a second power signal terminal PVEE, the first power signal terminal PVDD is used to receive a first voltage signal, and the second power signal terminal PVEE is used to receive a second voltage signal;

[0044] A driving transistor M0, wherein a gate of the driving transistor M0 is connected to a first node N1, a first electrode of the driving transistor M0 is connected to a first power signal terminal PVDD, and a second electrode of the driving transistor M0 is connected to a second node N2; the driving transistor M0 is used to provide a driving current in a light emitting stage;

[0045] A light emitting element D, wherein a first end of the light emitting element D is connected to the second node N2, and a second end of the light emitting element D is connected to the second power signal terminal PVEE; the light emitting element D is used to respond to the driving current and emit light in the light emitting stage;

[0046] A first reset module 10, the first reset module 10 is connected between the second reset signal terminal Vref2 and the first node N1, and the control terminal of the first reset module 10 is connected to the first reset signal terminal Vref1; the first reset module 10 is used to reset the first node N1 in the initialization stage;

[0047] The second reset module 20 is connected between the first reset signal terminal Vref1 and the second node N2, and the control terminal of the second reset module 20 is connected to the second reset signal terminal Vref2; the second reset module 20 is used to reset the second node N2 in the initialization stage.

[0048] It can be understood that in the embodiment provided by the present invention, the pixel driving circuit 100 at least includes a first power signal terminal PVDD, a second power signal terminal PVEE, a driving transistor M0, a light emitting element D, a first reset module 10 and a second reset module 20. Among them, the first power signal terminal PVDD, the driving transistor M0, the light emitting element D and the second power signal terminal PVEE are connected in series in sequence. The first power signal terminal PVDD is used to receive a first voltage signal of the pixel driving circuit 100, and the second power signal terminal PVEE is used to receive a second voltage signal of the pixel driving circuit 100. The first voltage signal and the second voltage signal form a voltage difference between the first pole and the second pole of the driving transistor M0 to generate a driving current. The driving current acts on the light emitting element D to make the light emitting element D emit light.

[0049] Further, the gate of the driving transistor M0 is connected to the first node N1, and the second electrode of the driving transistor M0 is connected to the second node N2. The first node N1 is also electrically connected to the first reset module 10. The second node N2 is also electrically connected to the second reset module 20. In the initialization stage, the first reset module 10 is used to reset the first node N1, and the second reset module 20 is used to reset the second node N2. The initialization stage can clear the residual voltage of the first node N1 and the second node N2 in the last light emission, so that the light emitting element D emits light according to the preset brightness, which is conducive to improving the accuracy of the light emitting brightness of the light emitting element D.

[0050] It can be understood that the first end of the first reset module 10 is connected to the second reset signal end Vref2, the second end of the first reset module 10 is connected to the first node N1, the control end of the first reset module 10 is connected to the first reset signal end Vref1, and the first reset module 10 is turned on or off under the action of the first reset signal output from the first reset signal end Vref1 to which its control end is connected. When the first reset module 10 is turned on, the second reset signal output from the second reset signal end Vref2 is transmitted to the first node N1 through the first reset module 10 to reset the first node N1.

[0051] Similarly, the first end of the second reset module 20 is connected to the first reset signal end Vref1, the second end of the second reset module 20 is connected to the second node N2, the control end of the second reset module 20 is connected to the second reset signal end Vref2, and the second reset module 20 is turned on or off under the action of the second reset signal output from the second reset signal end Vref2 to which its control end is connected. When the second reset module 20 is turned on, the first reset signal output from the first reset signal end Vref1 is transmitted to the second node N2 through the second reset module 20 to reset the second node N2.

[0052] The embodiment provided by the present invention, by setting two reset modules, namely the first reset module 10 and the second reset module 20, respectively resets the first node N1 and the second node N2 of the pixel driving circuit 100, and can clear the residual voltage of the first node N1 and the second node N2 in the last light emission, thereby making the light emitting element D emit light according to the preset brightness, which is beneficial to improve the accuracy of the light emitting brightness of the light emitting element D. In addition, the embodiment provided by the present invention includes two reset signal terminals, namely the first reset signal terminal Vref1 and the second reset signal terminal Vref2, and the first reset signal terminal Vref1 and the second reset signal terminal Vref2 provide reset signals for the second node N2 and the first node N1 respectively. Figure 4 and Figure 1 As shown, Figure 4 The pixel driving circuit provided by the embodiment of the present invention is shown in FIG. Figure 1 Compared with a pixel driving circuit in the related art shown in the figure, the technical problem that one reset signal line simultaneously resets two nodes in the related art, resulting in an overload on the reset signal line, is avoided. Figure 4 and Figure 2 As shown, Figure 4 The pixel driving circuit provided by the embodiment of the present invention is shown in Figure 2 Another pixel driving circuit in the related art shown in FIG. In the embodiment of the present invention, the first reset signal provided by the first reset signal terminal Vref1 and the second reset signal provided by the second signal terminal Vref2 are control terminal signals and input terminal signals of the first reset module 10 and the second reset module 20. Compared with the related art, a dedicated control terminal signal line is saved, the power consumption of the pixel driving circuit 100 is reduced, and the transmittance of the display panel is improved with fewer wiring.

[0053] It should be noted that Figure 3 Only a structural schematic diagram of the pixel driving circuit 100 in this embodiment is shown. In some other embodiments of the present application, the structure of the pixel driving circuit 100 may also be embodied in other forms, which is not specifically limited in the present application.

[0054] In an optional embodiment provided by the present invention, referring to Figure 5 As shown, Figure 5 The schematic diagram of another pixel driving circuit provided by an embodiment of the present invention is as follows. The pixel driving circuit 100 further includes a power supply voltage writing module 30;

[0055] The power supply voltage writing module 30 is connected between the first electrode of the driving transistor M0 and the first power supply signal PVDD terminal, and the control terminal of the power supply voltage writing module 30 is connected to the switch signal control terminal Emit; the power supply voltage writing module 30 is used to write the first voltage signal output by the first power supply signal terminal PVDD to the driving transistor M0 during the light-emitting stage.

[0056] It can be understood that the power supply voltage writing module 30 is connected in series between the first power supply signal terminal PVDD and the first electrode of the driving transistor M0, and the control terminal of the power supply voltage writing module 30 is connected to the switch signal control terminal Emit. The power supply voltage writing module 30 is turned on or off according to the signal of the switch signal control terminal Emit. When the power supply voltage writing module 30 is turned on, the first voltage signal of the first power supply signal terminal PVDD is transmitted to the first electrode of the driving transistor M0 through the power supply voltage writing module 30.

[0057] In the embodiment provided by the present invention, the power supply voltage writing module 30 is connected in series between the first power supply signal terminal PVDD and the first electrode of the driving transistor M0, so as to control the first voltage signal of the first power supply signal terminal PVDD to be transmitted to the driving transistor M0.

[0058] In an optional embodiment provided by the present invention, continue to refer to Figure 5 As shown, the pixel driving circuit 100 further includes a data writing module 40;

[0059] The data writing module 40 is connected between the first electrode of the driving transistor M0 and the data signal terminal Vdata, and the control terminal of the data writing module 40 is connected to the signal control terminal Scan; the data writing module 40 is used to provide a data signal to the driving transistor M0 during the data writing stage.

[0060] It can be understood that the data writing module 40 is connected in series between the data signal terminal Vdata and the first electrode of the driving transistor M0, and the control terminal of the data writing module 40 is connected to the signal control terminal Scan. The data writing module 40 is turned on or off according to the signal of the signal control terminal Scan. When the data writing module 40 is turned on, the data signal of the data signal terminal Vdata is transmitted to the first electrode of the driving transistor M0 through the data writing module 40.

[0061] In the embodiment provided by the present invention, the data writing module 40 is connected in series between the data signal terminal Vdata and the first electrode of the driving transistor M0, so as to control the data signal of the data signal terminal Vdata to be transmitted to the first electrode of the driving transistor M0.

[0062] In an optional embodiment provided by the present invention, continue to refer to Figure 5 As shown, the pixel driving circuit 100 further includes a storage capacitor Cst;

[0063] A first electrode of the storage capacitor Cst is connected to the first power signal terminal PVDD, and a second electrode of the storage capacitor Cst is connected to the first node N1 ; the storage capacitor Cst is used to maintain the potential of the first node N1 .

[0064] It is understandable that the storage capacitor Cst is connected in series between the first power signal terminal PVDD and the first node N1, and compensates for the voltage change of the first node N1 caused by the leakage current through its storage function, thereby ensuring the voltage of the first node N1 and improving the display quality of the display panel 100.

[0065] In an optional embodiment provided by the present invention, referring to Figure 6 As shown, Figure 6 The schematic diagram of another pixel driving circuit provided by an embodiment of the present invention is as follows. The pixel driving circuit 100 further includes a compensation module 50;

[0066] The compensation module 50 is connected between the second electrode of the driving transistor M0 and the first node N1 , and the control end of the compensation module 50 is connected to the signal control end Scan; the compensation module 50 is used to detect and self-compensate for the deviation of the threshold voltage of the driving transistor M0 .

[0067] It can be understood that the compensation module 50 is connected in series between the second electrode of the driving transistor M0 and the gate of the driving transistor M0, and the control end of the compensation module 50 is connected to the signal control end Scan. The compensation module 50 is turned on or off according to the signal of the signal control end Scan. Since the control ends of the compensation module 50 and the data writing module 40 are both connected to the signal control end Scan. Therefore, the data signal of the data signal end Vdata is transmitted to the first node N1 through the data writing module 40, the driving transistor M0 and the compensation module 50 to detect and self-compensate the deviation of the threshold voltage of the driving transistor M0.

[0068] In the embodiment provided by the present invention, the compensation module 50 is connected in series between the second electrode of the driving transistor M0 and the gate of the driving transistor M0, so as to detect and self-compensate for the deviation of the threshold voltage of the driving transistor M0. In addition, the control end of the compensation module 50 is connected to the signal control end Scan, and there is no need to set up a signal control end for the compensation module 50, which is conducive to simplifying the structure of the pixel driving circuit 100 and simplifying the overall structure of the display panel.

[0069] In an optional embodiment provided by the present invention, continue to refer to Figure 6 As shown, the pixel driving circuit 100 further includes a light emitting control module 60;

[0070] The light emitting control module 60 is connected between the second electrode of the driving transistor M0 and the second node N2 . The control end of the light emitting control module 60 is connected to the switch signal control end Emit. The light emitting control module 60 is used to turn off or turn on the light emitting element D.

[0071] It can be understood that the light control module 60 is connected in series between the second electrode of the driving transistor M0 and the light emitting element D, and the control end of the light control module 60 is connected to the switch signal control end Emit. The light control module 60 is turned on or off according to the signal of the switch signal control end Emit. When the light control module 60 is turned on, the driving current generated by the driving transistor M0 is transmitted to the first electrode of the light emitting element D through the light control module 60, driving the light emitting element D to emit light.

[0072] In the embodiment provided by the present invention, the light emitting control module 60 is connected in series between the second electrode of the driving transistor M0 and the light emitting element D, so as to control the driving current to be transmitted to the first electrode of the light emitting element D. In addition, the control end of the light emitting control module 60 is connected to the switch signal control end Emit, and there is no need to set up a signal control end for the light emitting control module 60, which is conducive to simplifying the structure of the pixel driving circuit 100 and simplifying the overall structure of the display panel.

[0073] In an optional embodiment provided by the present invention, referring to Figure 7 As shown, Figure 7 A schematic diagram of another pixel driving circuit provided by an embodiment of the present invention. The first reset module 10 includes a first transistor M1;

[0074] A gate of the first transistor M1 is connected to the first reset signal terminal Vref1 , a first electrode of the first transistor M1 is connected to the second reset signal terminal Vref2 , and a second electrode of the first transistor M1 is connected to the first node N1 .

[0075] It is understandable that the first reset module 10 includes a first transistor M1 . The first pole of the first transistor M1 is the first end of the first reset module 10 , the second pole of the first transistor M1 is the second end of the first reset module 10 , and the gate of the first transistor M1 is the control end of the first reset module 10 .

[0076] Further, the first transistor M1 is a P-type transistor or an N-type transistor. When it is a P-type transistor, its gate is turned on when receiving a low-level signal and is turned off when receiving a high-level signal; when it is an N-type transistor, its gate is turned on when receiving a high-level signal and is turned off when receiving a low-level signal. Figure 7 The illustrated embodiment is described by taking the first transistor M1 as a P-type transistor as an example. In some other embodiments of the present invention, the first transistor M1 may also be an N-type transistor, which is not specifically limited in the present invention.

[0077] In the embodiment provided by the present invention, the first reset module 10 includes a first transistor M1. When the gate of the first transistor M1 is connected to the low level signal of the first reset signal terminal Vref1, the first transistor M1 is turned on, and the second reset signal output by the second reset signal terminal Vref2 connected to the first electrode of the first transistor M1 is transmitted to the first node N1, the first node N1 is reset, and the residual voltage of the first node N1 in the last light emission is cleared, so that the light emitting element D emits light according to the preset brightness, which is conducive to improving the accuracy of the light emitting brightness of the light emitting element D.

[0078] In an optional embodiment provided by the present invention, continue to refer to Figure 7 As shown, the second reset module 20 includes a second transistor M2;

[0079] A gate of the second transistor M2 is connected to the second reset signal terminal Vref2 , a first electrode of the second transistor M2 is connected to the first reset signal terminal Vref1 , and a second electrode of the second transistor M2 is connected to the second node N2 .

[0080] It is understandable that the first reset module 10 includes a first transistor M1 . The first pole of the first transistor M1 is the first end of the first reset module 10 , the second pole of the first transistor M1 is the second end of the first reset module 10 , and the gate of the first transistor M1 is the control end of the first reset module 10 .

[0081] Further, the second transistor M2 is a P-type transistor or an N-type transistor. When it is a P-type transistor, its gate is turned on when it receives a low-level signal and is turned off when it receives a high-level signal; when it is an N-type transistor, its gate is turned on when it receives a high-level signal and is turned off when it receives a low-level signal. Figure 7 The illustrated embodiment is described by taking the second transistor M2 as a P-type transistor as an example. In some other embodiments of the present invention, the second transistor M2 may also be an N-type transistor, which is not specifically limited in the present invention.

[0082] In the embodiment provided by the present invention, the second reset module 20 includes a second transistor M2. When the second reset signal terminal Vref2 connected to the gate of the second transistor M2 is a low level signal, the second transistor M2 is turned on, and the first reset signal output by the first reset signal terminal Vref1 connected to the first electrode of the second transistor M2 is transmitted to the second node N2, and the second node N2 is reset, and the residual voltage of the second node N2 in the last light emission is cleared, so that the light emitting element D emits light according to the preset brightness, which is conducive to improving the accuracy of the light emitting brightness of the light emitting element D.

[0083] Reference Figure 8 As shown, Figure 8 A schematic diagram of the structure of another pixel driving circuit provided by an embodiment of the present invention. The power supply voltage writing module 30 includes a third transistor M3; the gate of the third transistor M3 is connected to the switch signal control terminal Emit, the first electrode of the third transistor M3 is connected to the first power supply signal terminal PVDD, and the second electrode of the third transistor M3 is connected to the first electrode of the driving transistor M0. Taking the third transistor M3 as a P-type transistor as an example, when the switch signal control terminal Emit connected to its gate is a low-level signal, the third transistor M3 is turned on, and the first voltage signal output from the first power supply signal terminal PVDD connected to the first electrode of the third transistor M3 is transmitted to the first electrode of the driving transistor M0.

[0084] The data writing module 40 includes a fourth transistor M4; the gate of the fourth transistor M4 is connected to the signal control terminal Scan, the first electrode of the fourth transistor M4 is connected to the data signal terminal Vdata, and the second electrode of the fourth transistor M4 is connected to the first electrode of the driving transistor M0. Taking the fourth transistor M4 as a P-type transistor as an example, when the signal control terminal Scan connected to its gate is a low-level signal, the fourth transistor M4 is turned on, and the data signal output by the data signal terminal Vdata connected to the first electrode of the fourth transistor M4 is transmitted to the first electrode of the driving transistor M0.

[0085] The compensation module 50 includes a fifth transistor M5; the gate of the fifth transistor M5 is connected to the signal control terminal Scan, the first electrode of the fifth transistor M5 is connected to the second electrode of the driving transistor M0, and the second electrode of the fifth transistor M5 is connected to the first node N1. Taking the fifth transistor M5 as a P-type transistor as an example, when the signal control terminal Scan connected to its gate is a low-level signal, the fifth transistor M5 is turned on, and the data signal output by the data signal terminal Vdata is transmitted to the first node N1 through the fourth transistor M4, the driving transistor M0 and the fifth transistor M5, so as to detect and self-compensate for the deviation of the threshold voltage of the driving transistor M0.

[0086] The light emitting control module 60 includes a sixth transistor M6; the gate of the sixth transistor M6 is connected to the switch signal control terminal Emit, the first electrode of the sixth transistor M6 is connected to the second electrode of the driving transistor M0, and the second electrode of the sixth transistor M6 is connected to the second node N2. Taking the sixth transistor M6 as a P-type transistor as an example, when the switch signal control terminal Emit connected to its gate is a low-level signal, the sixth transistor M6 is turned on, and the driving current generated by the driving transistor M0 is transmitted to the first electrode of the light emitting element D to drive the light emitting element D to emit light.

[0087] Based on the same inventive concept, the present invention also provides a pixel driving method, referring to Fig. 9 and Fig.10 As shown, Fig. 9A timing diagram of a pixel driving method provided by an embodiment of the present invention, Fig.10 The present invention provides a flowchart of a pixel driving method according to an embodiment of the present invention.

[0088] The pixel driving circuit 100 includes: a driving transistor M0, a light emitting element D, a power supply voltage writing module 30, a data writing module 40, a compensation module 50, a light emitting control module 60, a first reset module 10 and a second reset module 20;

[0089] The drive methods include:

[0090] Initialization phase T1, data writing phase T2 and light emitting phase T3;

[0091] The initialization phase T1 includes a first initialization phase T11 and a second initialization phase T12;

[0092] In the first initialization stage T11, the first reset module 10 is turned on, and the second reset signal at the second reset signal terminal Vref2 is transmitted to the first node N1 through the first reset module 10 to reset the first node N1;

[0093] In the second initialization stage T12, the second reset module 20 is turned on, and the first reset signal at the first reset signal terminal Vref1 is transmitted to the second node N2 through the second reset module 20 to reset the second node N2;

[0094] In the data writing stage T2, the data writing module 40 and the compensation module 50 are turned on; the data signal of the data signal terminal Vdata is transmitted to the first node N1 through the data writing module 40, the driving transistor M0 and the compensation module 50;

[0095] In the light-emitting stage T3, the power supply voltage writing module 30 and the light-emitting control module 60 are turned on; the first voltage signal of the first power supply signal terminal PVDD is transmitted to the first electrode of the driving transistor M0 through the power supply voltage writing module 30, and the driving transistor M0 is driven to form a current which is transmitted to the light-emitting element D through the light-emitting control module 60;

[0096] The data writing phase T2 is included in the second initialization phase T12.

[0097] It can be understood that the initialization stage T1 is used to initialize the pixel driving circuit 100. Specifically, the initialization stage T1 includes a first initialization stage T11 and a second initialization stage T12. The first initialization stage T11 is used to reset the first node N1 through the first reset module 10; the second initialization stage T12 is used to reset the second node N2 through the second reset module 20.

[0098] Specifically, in the first initialization stage T11, the first reset signal output by the first reset signal terminal Vref1 is a low level signal, and the second reset signal output by the second reset signal terminal Vref2 is a 0 level signal. The first reset module 10 is turned on, and the 0 level signal output by the second reset signal terminal Vref2 connected to the first terminal of the first reset module 10 is transmitted to the first node N1, and the first node N1 is reset.

[0099] In the second initialization stage T12, the second reset signal output by the second reset signal terminal Vref2 is a low level signal, and the first reset signal output by the first reset signal terminal Vref1 is a 0 level signal. The second reset module 10 is turned on, and the 0 level signal output by the first reset signal terminal Vref1 connected to the first terminal of the second reset module 20 is transmitted to the second node N2, and the second node N2 is reset.

[0100] It can be understood that the first reset signal terminal Vref1 and the second reset signal terminal Vref2 are mutually the first terminal and the control terminal of the first reset module 10 and the second reset module 20. The first node N1 and the second node N2 are reset in sequence through the timing change of the first reset signal terminal Vref1 and the second reset signal terminal Vref2. This not only avoids the excessive load of the reset signal line caused by resetting multiple nodes by one reset signal line, but also avoids the increase of power consumption and the reduction of transmittance of the driving circuit 100 caused by multiple control lines.

[0101] Further, in the second initialization stage T12, while resetting the second node N2, the data writing stage T2 is performed. Specifically, the signal control terminal Scan outputs a low level signal. The data writing module 40 and the compensation module 50 connected to the control terminal and the signal control terminal Scan are turned on. The data signal of the data signal terminal Vdata is transmitted to the first node N1 through the data writing module 40, the driving transistor M0 and the compensation module 50.

[0102] Further, in the light-emitting stage T3, the switch signal control terminal Emit outputs a low-level signal. The power supply voltage writing module 30 and the light-emitting control module 60 connected to the switch signal control terminal Emit are turned on. The power supply voltage writing module 30 transmits the first voltage signal of the first power supply signal terminal PVDD to the first electrode of the driving transistor M0. The driving transistor M0 generates a driving current according to the first voltage signal of the first electrode and the data signal of the first node N1, and transmits the driving current to the first electrode of the light-emitting element D to drive the light-emitting element D to emit light.

[0103] Based on the same inventive concept, the present invention further provides a display device 200, referring to Fig.11 As shown, Fig.11A top view of a display device provided by an embodiment of the present invention. The display device 200 includes the pixel driving circuit 100 in any of the above embodiments.

[0104] The display device 200 provided in the embodiment of the present invention can be any electronic device with a display function, such as a touch screen, a mobile phone, a tablet computer, a laptop computer, an e-book, or a television. The display device 200 provided in the embodiment of the present invention has the beneficial effects of the pixel driving circuit 100 provided in the embodiment of the present invention. For details, reference can be made to the specific description of the pixel driving circuit 100 in the above embodiments, which will not be repeated in this embodiment.

[0105] It should be noted that Fig.11 The display device 200 is illustrated by taking a rectangular display device 200 as an example. In some other embodiments of the present application, the display device 200 may also be embodied in other shapes, such as a circular, elliptical or irregular structure.

[0106] In summary, the pixel driving circuit and driving method thereof, and the display device provided by the present invention achieve at least the following beneficial effects:

[0107] The embodiment provided by the present invention, by setting two reset modules, namely the first reset module and the second reset module, respectively resets the first node and the second node of the pixel driving circuit, and can clear the residual voltage of the first node and the second node in the last light emission, so as to make the light-emitting element emit light according to the preset brightness, thus helping to improve the accuracy of the light-emitting brightness of the light-emitting element. In addition, the embodiment provided by the present invention includes two reset signal terminals, namely the first reset signal terminal and the second reset signal terminal, and the first reset signal terminal and the second reset signal terminal provide reset signals for the second node and the first node respectively. It avoids the technical problem that one reset signal line resets two nodes at the same time, resulting in an overload of the reset signal line. In addition, the first reset signal provided by the first reset signal terminal and the second reset signal provided by the second signal terminal are respectively the control terminal signal and the input terminal signal of the first reset module and the second reset module, saving a special control terminal signal line, reducing the power consumption of the pixel driving circuit, and improving the transmittance of the display panel.

[0108] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A pixel driving circuit, characterized in that: include: a first power signal terminal and a second power signal terminal, wherein the first power signal terminal is used to receive a first voltage signal, and the second power signal terminal is used to receive a second voltage signal; A driving transistor, wherein a gate of the driving transistor is connected to a first node, a first electrode of the driving transistor is connected to the first power signal terminal, and a second electrode of the driving transistor is connected to a second node; the driving transistor is used to provide a driving current in a light emitting stage; A light emitting element, wherein a first end of the light emitting element is connected to the second node, and a second end of the light emitting element is connected to the second power signal end; The light emitting element is used to respond to the driving current and emit light in the light emitting stage; A first reset module, wherein the first reset module is connected between the second reset signal terminal and the first node, and the control terminal of the first reset module is connected to the first reset signal terminal; the first reset module is used to reset the first node in an initialization phase; The second reset module is connected between the first reset signal terminal and the second node, and the control terminal of the second reset module is connected to the second reset signal terminal; the second reset module is used to reset the second node in the initialization stage.

2. The pixel driving circuit according to claim 1, characterized in that: The pixel driving circuit also includes a power supply voltage writing module; The power supply voltage writing module is connected between the first electrode of the driving transistor and the first power supply signal terminal, and the control terminal of the power supply voltage writing module is connected to the switch signal control terminal; the power supply voltage writing module is used to write the first voltage signal output from the first power supply signal terminal to the driving transistor during the light-emitting stage.

3. The pixel driving circuit according to claim 1, characterized in that: The pixel driving circuit also includes a data writing module; The data writing module is connected between the first electrode of the driving transistor and the data signal terminal, and the control terminal of the data writing module is connected to the signal control terminal; the data writing module is used to provide a data signal to the driving transistor in the data writing stage.

4. The pixel driving circuit according to claim 1, characterized in that: The pixel driving circuit also includes a storage capacitor; A first electrode of the storage capacitor is connected to the first power signal terminal, and a second electrode of the storage capacitor is connected to the first node; The storage capacitor is used to maintain the potential of the first node.

5. The pixel driving circuit according to claim 3, characterized in that: The pixel driving circuit further includes a compensation module; The compensation module is connected between the second electrode of the driving transistor and the first node, and the control end of the compensation module is connected to the signal control end; the compensation module is used to detect and self-compensate for the deviation of the threshold voltage of the driving transistor.

6. The pixel driving circuit according to claim 2, characterized in that: The pixel driving circuit also includes a light emitting control module; The light emitting control module is connected between the second electrode of the driving transistor and the second node, and the control end of the light emitting control module is connected to the switch signal control end; The light emitting control module is used to turn off or turn on the light emitting element.

7. The pixel driving circuit according to claim 1, characterized in that: The first reset module includes a first transistor; The gate of the first transistor is connected to the first reset signal terminal, the first electrode of the first transistor is connected to the second reset signal terminal, and the second electrode of the first transistor is connected to the first node.

8. The pixel driving circuit according to claim 1, characterized in that: The second reset module includes a second transistor; A gate of the second transistor is connected to the second reset signal terminal, a first electrode of the second transistor is connected to the first reset signal terminal, and a second electrode of the second transistor is connected to the second node.

9. A pixel driving method, for driving the pixel driving circuit according to any one of claims 1 to 8, wherein the pixel driving circuit comprises: A driving transistor, a light emitting element, a power supply voltage writing module, a data writing module, a compensation module, a light emitting control module, a first reset module and a second reset module; Characterized in that the driving method comprises: Initialization phase, data writing phase and light emitting phase; The initialization phase includes a first initialization phase and a second initialization phase; In the first initialization stage, the first reset module is turned on, and the second reset signal at the second reset signal end is transmitted to the first node through the first reset module to reset the first node; In the second initialization stage, the second reset module is turned on, and the first reset signal at the first reset signal end is transmitted to the second node through the second reset module to reset the second node; In the data writing stage, the data writing module and the compensation module are turned on; the data signal at the data signal end is transmitted to the first node through the data writing module, the driving transistor and the compensation module; In the light-emitting stage, the power supply voltage writing module and the light-emitting control module are turned on; the first voltage signal at the first power supply signal end is transmitted to the first electrode of the driving transistor through the power supply voltage writing module, and the driving transistor is driven to form a current which is transmitted to the light-emitting element through the light-emitting control module; The data writing phase is included in the second initialization phase.

10. A display device, characterized in that: The invention comprises the pixel driving circuit as claimed in any one of claims 1 to 8.

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