A pixel driving circuit, a display panel and a display device

Abstract

The present invention discloses a pixel driving circuit, a display panel and a display device. The pixel driving circuit includes: a driving module, a first initialization module, a storage module, a threshold compensation module, a data writing module and a light emitting module; at least one of the transistors in the driving module, the first initialization module and the threshold compensation module adopts a first double-gate structure; the transistor adopting the first double-gate structure includes a control terminal and a first bottom gate electrode; the first bottom gate electrode is used to access a first modulation voltage. By adopting the first double-gate structure for at least one of the transistors in the driving module, the first initialization module and the threshold compensation module, the hysteresis phenomenon of the transistors in the pixel driving circuit is improved, and thus the display effect of the display panel is enhanced.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and in particular, to a pixel driving circuit, a display panel, and a display device. Background Art

[0002] Thin film transistors (i.e., TFTs) are widely used as switching elements in display panels (e.g., liquid crystal panels or organic light emitting display panels). Therefore, an array substrate formed with thin film transistors is a basic element of a display panel configured for a display device.

[0003] However, in the display driving circuit of the array substrate, there is a hysteresis phenomenon in thin film transistors, which seriously affects the display effect of the display device. Summary of the Invention

[0004] Embodiments of the present invention provide a pixel driving circuit, a display panel, and a display device to improve the hysteresis phenomenon of transistors in the pixel driving circuit.

[0005] In a first aspect, embodiments of the present invention provide a pixel driving circuit, including: a driving module, a first initialization module, a storage module, a threshold compensation module, a data writing module, and a light emitting module;

[0006] A first end of the driving module is used to input a signal input from a first power supply; a second end of the driving module is used to provide a light emitting driving signal for the light emitting module; the storage module is connected between a control end of the driving module and the first end of the driving module; the threshold compensation module is connected between the control end of the driving module and the second end of the driving module;

[0007] The data writing module is connected to the first end of the driving module and is used to transmit a data voltage to the driving module; the first initialization module is connected between a first reference voltage output terminal and the first end of the driving module and is used to provide a first initialization voltage for the driving module;

[0008] At least one of the transistors in the driving module, the first initialization module, and the threshold compensation module adopts a first double-gate structure; the transistor adopting the first double-gate structure includes a control end and a first bottom gate electrode; the first bottom gate electrode is used to access a first modulation voltage.

[0009] In a second aspect, embodiments of the present invention further provide a display panel, including the pixel driving circuit according to any one of the first aspect.

[0010] In a third aspect, embodiments of the present invention further provide a display device, including the display panel according to the second aspect.

[0011] The present invention provides a pixel driving circuit, a display panel, and a display device. The pixel driving circuit includes: a driving module, a first initialization module, a storage module, a threshold compensation module, a data writing module, and a light-emitting module; a first end of the driving module is used to input a signal from a first power supply; a second end of the driving module is used to provide a light-emitting driving signal for the light-emitting module; the storage module is connected between a control end of the driving module and the first end of the driving module; the threshold compensation module is connected between the control end of the driving module and the second end of the driving module; the data writing module is connected to the first end of the driving module and is used to transmit a data voltage to the driving module; the first initialization module is connected between a first reference voltage output end and the first end of the driving module and is used to provide a first initialization voltage for the driving module; at least one of the transistors in the driving module, the first initialization module, and the threshold compensation module adopts a first double-gate structure; the transistor adopting the first double-gate structure includes a control end and a first bottom gate electrode; the first bottom gate electrode is used to access a first modulation voltage. By adopting the first double-gate structure for at least one of the transistors in the driving module, the first initialization module, and the threshold compensation module, the hysteresis phenomenon of the transistors in the pixel driving circuit is improved, thereby enhancing the display effect of the display panel. Moreover, the first bottom gate electrode can play a certain role in light shielding, slowing down the degradation phenomenon of the transistor device in the blue light illumination reliability test and improving the reliability of the display panel. Description of the Drawings

[0012] Figure 1 It is a schematic structural diagram of a pixel driving circuit provided by an embodiment of the present invention;

[0013] Figure 2 It is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0014] Figure 3 It is a schematic cross-sectional structural diagram of a transistor with a first double-gate structure;

[0015] Figure 4 It is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0016] Figure 5 It is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0017] Figure 6 It is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0018] Figure 7 It is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0019] Figure 8 It is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0020] Figure 9 A timing diagram of a pixel driving circuit provided by an embodiment of the present invention;

[0021] Figure 10 A schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0022] Figure 11 A schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0023] Figure 12 A schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0024] Figure 13 A schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0025] Figure 14 A schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0026] Figure 15 A schematic structural diagram of a display device provided by an embodiment of the present invention. Detailed implementation manners

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only parts related to the present invention are shown in the drawings, rather than all the structures.

[0028] In the prior art, in a traditional pixel driving circuit, such as a 7T1C circuit, the transistors in the pixel driving circuit are usually single-gate P-type transistors or N-type transistors. During the process of turning on the transistors at different stages, the transistors are prone to hysteresis problems, seriously affecting the display effect of the display panel.

[0029] In an embodiment of the present invention, by providing a pixel driving circuit, a display panel, and a display device, the pixel driving circuit includes: a driving module, a first initialization module, a storage module, a threshold compensation module, a data writing module, and a light emitting module; a first end of the driving module is used to input a signal input by a first power supply; a second end of the driving module is used to provide a light emitting driving signal for the light emitting module; the storage module is connected between a control end of the driving module and the first end of the driving module; the threshold compensation module is connected between the control end of the driving module and the second end of the driving module; the data writing module is connected to the first end of the driving module and is used to transmit a data voltage to the driving module; the first initialization module is connected between a first reference voltage output end and the control end of the driving module and is used to provide a first initialization voltage for the driving module; at least one of the transistors in the driving module, the first initialization module, and the threshold compensation module adopts a first double-gate structure; the transistor adopting the first double-gate structure includes a control end and a first bottom gate electrode; the first bottom gate electrode is used to access a first modulation voltage. By adopting the first double-gate structure for at least one of the transistors in the driving module, the first initialization module, and the threshold compensation module in the pixel driving circuit, and accessing the first modulation voltage on the first bottom gate electrode of the first double-gate structure, the threshold voltage of the transistor of the first double-gate structure is modulated, the hysteresis phenomenon of the transistor is improved, and further the phenomena of smear, afterimage, and uneven display of the display panel are improved, ensuring the normal display of the display panel. And the first bottom gate electrode can play a certain role in light shielding, slowing down the degradation phenomenon of the transistor device in the blue light illumination reliability test. For example, for reliability tests such as positive bias illumination (PBIS) and negative bias illumination (NBIS), the first bottom gate electrode can effectively slow down the degradation of the transistor and improve the reliability of the display panel.

[0030] The above is the core idea of the present invention. Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0031] Figure 1 FIG. is a schematic structural diagram of a pixel driving circuit provided by an embodiment of the present invention. Figure 2 FIG. is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention, as Figure 1 and Figure 2As shown, the pixel driving circuit includes: a driving module 101, a first initialization module 102, a storage module 103, a threshold compensation module 104, a data writing module 105, and a light emitting module 106; a first end of the driving module 101 is used for inputting a signal from a first power supply; a second end of the driving module 101 is used for providing a light emitting driving signal to the light emitting module 106; the storage module 103 is connected between a control end of the driving module 101 and the first end of the driving module 101; the threshold compensation module 104 is connected between the control end of the driving module 101 and the second end of the driving module 101; the data writing module 105 is connected to the first end of the driving module 101 and is used for transmitting a data voltage to the driving module 101; the first initialization module 102 is connected between a first reference voltage output terminal and the control end of the driving module 101 and is used for providing a first initialization voltage to the driving module 101; at least one of the transistors in the driving module 101, the first initialization module 102, and the threshold compensation module 104 adopts a first double-gate structure; the transistor adopting the first double-gate structure includes a control end and a first bottom gate electrode 1001; the first bottom gate electrode 1001 is used for accessing a first modulation voltage V1.

[0032] Among them, the light-emitting module 106 can be, for example, an OLED (Organic Light-Emitting Diode). OLED is a current-type device and can only emit light under the action of a driving current. The driving module 101 can generate a corresponding driving current according to the data voltage signal to drive the light-emitting module 106 to display different gray levels, so that the display panel can display the image to be displayed. The specific working process of the pixel driving circuit includes an initialization stage, a data writing stage and a light-emitting stage; the initialization stage includes a first initialization stage, in which the first initialization module 102 is connected to the control end of the driving module 101. In the first initialization stage, the first initialization module 102 is turned on, and the first initialization module 102 transmits the first initialization voltage Vref1 output by the first reference voltage output end to the control end of the driving module 101 for initialization, thereby clearing the residual charge of the previous frame of the picture to improve the display effect of the display panel; in the data writing stage, the first initialization module 102 is turned off, the data writing module 105 and the threshold compensation module 104 are turned on, the data writing module 105 is connected to the first end of the driving module 101, the data writing module 105 writes the data voltage signal Vdata into the driving module 101, and the threshold compensation module 104 is connected to the driving module 101. Between the control end of the driving module 101 and the second end of the driving module 101, the threshold compensation module 104 can capture the threshold voltage of the driving module 101 to the control end of the driving module 101 to achieve threshold voltage compensation; and the storage module 103 is connected between the control end of the driving module 101 and the first end of the driving module 101, and the storage module 103 can maintain the potential of the control end of the driving module 101 to avoid the potential of the control end of the driving module 101 being coupled and changed when the first initialization module 102 is turned off; in the light-emitting stage, the first initialization module 102, the data writing module 105, and the threshold compensation module 104 are all turned off, the driving module 101 is turned on, and the second end of the driving module 101 is connected to the light-emitting element for providing a light-emitting driving current to the light-emitting module 106. The light-emitting module 106 emits light in response to the light-emitting driving current, thereby displaying the brightness to be displayed. In the prior art, the transistors of the driving module 101, the first initialization module 102, and the threshold compensation module 104 are traditional single-gate P-type transistors, which may cause hysteresis during use, thereby affecting the display effect of the display panel. By adopting a first dual-gate structure for at least one of the transistors of the driving module 101, the first initialization module 102, and the threshold compensation module 104, for example, Figure 2 As shown, the transistors of the driving module 101 are all in the first dual-gate structure as an example for demonstration. Figure 3 is a schematic diagram of the cross-sectional structure of a first dual-gate transistor, as shown in Figure 3As shown, the transistor with the first double-gate structure includes a control terminal and a first bottom gate electrode 1001. The transistor with the first double-gate structure includes a semiconductor layer 121, a first gate 122, a source 123, a drain 124, and a second gate 125. That is, the second gate is the first bottom gate electrode 1001. The first bottom gate electrode 1001 can play a role in shielding light, improving the hysteresis phenomenon of the transistor, thereby improving the ghosting, afterimage, and uneven display phenomena of the display panel, and ensuring the normal display of the display panel. The first bottom gate electrode 1001 is connected to a first modulation voltage V1. The above first modulation voltage V1 can be set independently or can be a signal already existing in the pixel driving circuit. For example, the first modulation voltage V1 can be selected as the first power signal PVDD output by the first power supply, or can be the high voltage signal VGH of the gate driving circuit. In addition, it can also be the second power signal PVEE output by the second power supply connected to the light-emitting module, the low voltage signal VGL of the gate driving circuit, or the first reference voltage VREF1 output by the first reference voltage output terminal.

[0033] In addition, the first modulation voltage V1 can also adjust the threshold voltage of the first gate 122 (control terminal). Specifically, the first bottom gate electrode 1001 is connected to the first modulation voltage V1, which affects the width of the conductive channel in the semiconductor layer of the transistor, thereby affecting the threshold voltage of the transistor. The first modulation voltage V1 can be a fixed voltage signal. The first modulation voltage V1 can be a positive voltage signal or a negative voltage signal. When it is necessary to adjust the threshold voltage of the transistor, the specific voltage value of the first modulation voltage V1 can be set. For example, for a P-type transistor, when the first bottom gate electrode 1001 is connected to the first modulation voltage V1 as PVDD, for example, 6V, the first bottom gate electrode 1001 forms a positive electric field, making it difficult for the transistor channel to open, resulting in a negative shift of the threshold voltage. When the value of the first bottom gate electrode 1001 is small, for example, taking a negative value, a negative electric field will be formed, making it easy for the transistor channel to turn on, resulting in a positive shift of the threshold voltage.

[0034] Optionally, the first modulation voltage V1 is less than or equal to 3V.

[0035] When the first modulation voltage V1 is less than or equal to 3V, generally the first modulation voltage V1 is no longer negatively biased. For key modules in the pixel driving circuit, for example, the transistors in the driving module 101, the first initialization module 102, and the threshold compensation module 104 are key transistors. To avoid difficult opening, which may cause an increase in the low-voltage signal VGL of the gate driving circuit and thus an increase in the overall power consumption, this embodiment can effectively control the transistors in the above-mentioned modules not to be in a negatively biased state, so that the key transistors are easy to open. During the transistor turning-on process, the first modulation voltage V1 can mitigate the threshold voltage deviation phenomenon caused by the long-term application of voltage on the control terminal in the transistor. The first bottom gate electrode 1001 of the transistor with the first double-gate structure is connected to the first modulation voltage V1 less than or equal to 3V to avoid the negative bias of the threshold voltage in the transistor, ensure the normal turning-on of the transistor, and effectively realize the driving process of the pixel driving circuit.

[0036] Optionally, the first modulation voltage V1 is less than or equal to 0V. To further improve the transistor turning-on speed, this embodiment can effectively control the transistor to be positively biased. Specifically, the first bottom gate electrode 1001 of the transistor with the first double-gate structure is connected to the first modulation voltage V1 less than or equal to 0V, so that the threshold voltage in the transistor has a positive bias phenomenon, reducing the turning-on difficulty of the transistor, shortening the turning-on time of the transistor, improving the speed of the pixel driving circuit, and ensuring the display effect of the display panel.

[0037] In the embodiment of the present invention, at least one of the transistors in the driving module, the first initialization module, and the threshold compensation module in the pixel driving circuit adopts the first double-gate structure, and the first modulation voltage is connected to the first bottom gate electrode of the first double-gate structure, so that the first modulation voltage can modulate the threshold voltage of the transistors with the first double-gate structure in the driving module, the first initialization module, and the threshold compensation module, reducing the negative bias phenomenon of the transistors, improving the hysteresis phenomenon of the transistors, and further improving the phenomena of smear, afterimage, and uneven display of the display panel, ensuring the normal display of the display panel.

[0038] Optionally, Figure 4 is a schematic structural diagram of another pixel driving circuit provided by the embodiment of the present invention, as Figure 4 shown, the transistor of the threshold compensation module 104 adopts the first double-gate structure.

[0039] Among them, the transistors in the threshold compensation module 104 can adopt a first double-gate structure. By connecting the first bottom gate electrode 1001 to access the first modulation voltage V1, when the transistors in the threshold compensation module 104 are negatively biased, the threshold voltage of the transistors is pulled back to the normal threshold voltage, avoiding the difficulty of turning on the transistors under the condition of negative threshold voltage deviation. A smaller low-level signal is required to enable the transistors in the threshold compensation module 104 to successfully write the voltage signal, effectively reducing the power consumption of the pixel driving circuit.

[0040] Optionally, Figure 5 Another structural schematic diagram of the pixel driving circuit provided by the embodiment of the present invention is shown in Figure 5 As shown, the transistors of the first initialization module 102 adopt a first double-gate structure.

[0041] Among them, when the transistors in the first initialization module 102 are in the on state, the gate-source voltage difference is small. If the threshold voltage is negatively biased, it is difficult for the first initialization module 102 to conduct, thus making it difficult to ensure the initialization reset of the control terminal of the driving module 101. The transistors in the first initialization module 102 can adopt a first double-gate structure. When the transistors in the first initialization module 102 are negatively biased, the threshold voltage of the transistors is pulled back to the normal threshold voltage, avoiding the difficulty of turning on the transistors in the first initialization module 102 under the condition of negative threshold voltage deviation. A low-level signal with a larger absolute value is required to enable the transistors in the threshold compensation module 104 to successfully write the first initialization voltage Vref1, effectively reducing the power consumption of the pixel driving circuit. At the same time, after the transistors in the first initialization module 102 are turned on, the charge residue of the previous frame in the driving module 101 can be cleared in time, ensuring the display effect and avoiding problems such as ghosting, afterimage, and uneven display.

[0042] Optionally, Figure 6 Another structural schematic diagram of the pixel driving circuit provided by the embodiment of the present invention is shown in Figure 6 As shown, the first initialization voltage Vref1 is multiplexed as the first modulation voltage V1.

[0043] Among them, as Figure 6As shown, the transistors in the driving module 101, the first initialization module 102, and the threshold compensation module 104 all adopt the first double-gate structure. The first initialization voltage Vref1 in the pixel driving circuit is multiplexed as the first modulation voltage V1, avoiding the need to set additional signal lines, reducing the number of signal lines, and lowering the process difficulty. At the same time, the first initialization voltage Vref1 is at a low level, so that the threshold voltage of the transistors with the first double-gate structure in the driving module 101, the first initialization module 102, or the threshold compensation module 104 will not have a negative bias phenomenon, reducing the difficulty of turning on the transistors, thereby reducing the power consumption of the pixel driving circuit and increasing the service life. In addition, other negative value signals such as the low voltage signal VGL of the gate driving circuit can be set as the first modulation voltage V1, and this embodiment does not make special limitations on this. Exemplarily, when the threshold voltage of the transistor undergoes a negative shift, the original threshold voltage of -8V undergoes a negative shift and becomes -9V. At this time, the first modulation voltage V1 is a fixed voltage less than 0V, and the threshold voltage is pulled negative to -7V, that is, it is corrected to a threshold voltage with a smaller absolute value, thus avoiding the difficulty of turning on the transistor.

[0044] Optionally, Figure 7 is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention. As Figure 7 shown, the pixel driving circuit further includes: a second initialization module 107; the second initialization module 107 is connected between the second reference voltage output terminal VREF2 and the first end of the light-emitting module 106, and is used to provide the second initialization voltage Vref2 for the light-emitting module 106.

[0045] Among them, the pixel driving circuit further includes a second initialization module 107; the second initialization module 107 is connected between the second reference voltage output terminal VREF2 and the first end of the light-emitting module 106, so as to provide the second initialization voltage Vref2 for the light-emitting module 106, which can clear the residual charge of the previous frame of the picture, so that the light-emitting module 106 can display the to-be-displayed brightness more accurately, thereby improving the picture quality of the display panel. The control end of the second initialization module 107 can be connected to the first scan signal line or the second scan signal line, so that the second initialization module 107 can initialize the light-emitting module 106 in the first initialization stage or the data writing stage, which can reduce the number of signal lines, lower the manufacturing cost, and simplify the complexity of the pixel driving circuit.

[0046] Optionally, Figure 8 is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention. As Figure 8As shown, the pixel driving circuit further includes: a first light-emitting control module 108 and a second light-emitting control module 109; the first light-emitting control module 108 is connected between the first power supply PVDD and the first end of the driving module 101; the second light-emitting control module 109 is connected between the second end of the driving module 101 and the first end of the light-emitting module 106, and the second end of the light-emitting module 106 is connected to the second power supply PVEE.

[0047] Wherein, the pixel driving circuit further includes a first light-emitting control module 108 and a second light-emitting control module 109; the first light-emitting control module 108 is connected between the first power supply PVDD and the first end of the driving module 101; the second light-emitting control module 109 is connected between the second end of the driving module 101 and the first end of the light-emitting module 106, and the second end of the light-emitting module 106 is connected to the second power supply PVEE. During the light-emitting stage, the first light-emitting control module 108 and the second light-emitting control module 109 are turned on, a voltage difference is generated between the first end and the second end of the driving module 101, and then a light-emitting driving signal is output to the first end of the light-emitting module 106. The second end of the light-emitting module 106 is connected to the second power supply PVEE, so that a path is formed among the first power supply PVDD, the first light-emitting control module 108, the driving module 101, the second light-emitting control module 109, the light-emitting module 106 and the second power supply PVEE, and the light-emitting module 106 emits light to display the brightness to be displayed.

[0048] Optionally, Figure 9 is a timing diagram of a pixel driving circuit provided by an embodiment of the present invention, as Figure 6 and Figure 9, the storage module 103 includes a first capacitor Cst; the first light emission control module 108 includes a first transistor T1; the data writing module 105 includes a second transistor T2; the driving module 101 includes a third transistor T3; the threshold compensation module 104 includes a fourth transistor T4; the first initialization module 102 includes a fifth transistor T5; the second light emission control module 109 includes a sixth transistor T6; the second initialization module 107 includes a seventh transistor T7; the control terminal of the third transistor T3 is respectively connected to the second terminal of the fifth transistor T5 and the first terminal of the fourth transistor T4; the first terminal of the third transistor T3 is connected to the second terminal of the first transistor T1; the first terminal of the first transistor T1 is connected to a first power supply PVDD; the second terminal of the third transistor T3 is respectively connected to the second terminal of the fourth transistor T4 and the first terminal of the sixth transistor T6; the second terminal of the sixth transistor T6 is connected to the first terminal of the light emission module 106; the first terminal of the fifth transistor T5 is connected to a first reference voltage output terminal VREF1; the first terminal of the second transistor T2 is connected to a data signal line DATA; the second terminal of the second transistor T2 is connected to the first terminal of the third transistor T3; the first terminal of the seventh transistor T7 is connected to a second reference voltage output terminal VREF2; the second terminal of the seventh transistor T7 is connected to the first terminal of the light emission module 106; at least one of the third transistor T3, the fourth transistor T4, and the fifth transistor T5 adopts a first double-gate structure; the control terminals of the first transistor T1 and the sixth transistor T6 are connected to a light emission control signal line EM; the control terminal of the fifth transistor T5 is connected to a first scan signal line; the control terminals of the fourth transistor T4, the second transistor T2, and the seventh transistor T7 are connected to a second scan signal line.

[0049] Among them, the first transistor T1, the second transistor T2, the third transistor T3, the fourth transistor T4, the fifth transistor T5, the sixth transistor T6, and the seventh transistor are all P-type transistors. P-type transistors conduct when the input is at a low level and cut off when the input is at a high level. Taking the first initialization voltage Vref1 as a low-level signal as an example, the working principle of the pixel driving circuit is described. In the initialization stage, the signal Sn-1 on the first scan signal line is at a low level, the signal Sn on the second scan signal line and the signal Emit on the emission control signal line EM are at high levels. At this time, the fifth transistor T5 conducts, and the first transistor T1, the second transistor T2, the third transistor T3, the fourth transistor T4, the sixth transistor T6, and the seventh transistor T7 cut off. The potential on the first reference voltage output terminal is applied to the first capacitor Cst through the fifth transistor T5, that is, the potential of the first node N1 is the first initialization voltage Vref1. At this time, the potential of the control terminal of the driving transistor M3 is also the first initialization voltage Vref1. In the data writing stage, the signal Sn on the second scan line is at a low level, the signal Sn-1 on the first scan line and the signal Emit on the emission control signal line EM are at high levels. The second transistor T2, the fourth transistor T4, and the seventh transistor T7 conduct. At this time, the data signal Vdata is written into the second transistor T2 and the fourth transistor T4. The potential of the control terminal of the driving transistor T3 is the first initialization voltage Vref1, which is also a low potential, and the third transistor T3 also conducts. The data signal Vdata on the data signal line DATA is written into the second transistor T2, the third transistor T3, and the fourth transistor T4 and applied to the first node N1. The potential of the first node N1 is gradually pulled up by the potential on the data signal line DATA. When the voltage difference between the gate voltage and the source voltage of the third transistor T3 is less than or equal to the threshold voltage of the third transistor T3, the third transistor T3 will be in a cut-off state. In the data writing stage, the seventh transistor T7 also conducts. The seventh transistor M7 writes the second initialization voltage Vref2 on the second reference voltage line into the first pole of the light-emitting module 106 to initialize the potential of the first pole of the light-emitting module 106, which can reduce the influence of the voltage of the first pole of the light-emitting module 106 in the previous frame on the voltage of the first pole of the light-emitting module 106 in the next frame and further improve the display uniformity. In the light-emitting stage, the signal Emit on the emission control signal line EM is at a low level, the signal Sn-1 on the first scan signal line and the signal Sn on the second scan signal line are at high levels. At this time, the first transistor T1 and the sixth transistor T6 conduct, and a path is formed between the first power supply PVDD and the second power supply PVEE. The third transistor T3 outputs a light-emitting driving signal to the light-emitting module 106, and the light-emitting module 106 emits light.Furthermore, at least one of the third transistor T3 in the driving module 101, the fourth transistor T4 in the threshold compensation module 104, and the fifth transistor T5 in the first initialization module 102 can adopt the first double-gate structure. Exemplarily, taking the third transistor T3, the fourth transistor T4, and the fifth transistor T5 as the first double-gate structure as an example for display, as follows. Figure 6 As shown, by connecting the same first modulation voltage V1 to the first bottom gate electrodes 1001 of the third transistor T3, the fourth transistor T4, and the fifth transistor T5 respectively, the fifth transistor T5 is normally turned on in the initialization stage, and the third transistor T3 and the fourth transistor T4 are normally turned on in the data writing stage, reducing the negative bias phenomenon of the threshold voltages of the third transistor T3, the fourth transistor T4, and the fifth transistor T5, and ensuring the normal display of the display panel.

[0050] Optionally, Figure 10 is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention, as Figure 6 and Figure 10 shown, the first initialization voltage Vref1 or the second initialization voltage Vref2 is multiplexed as the first modulation voltage V1.

[0051] Among them, as Figure 6 shown, the first initialization voltage Vref1 can be connected to the first bottom gate electrode 1001 of the third transistor T3, the fourth transistor T4, or the fifth transistor T5, or as Figure 10 shown, the second initialization voltage Vref2 can be connected to the first bottom gate electrode 1001 of the third transistor T3, the fourth transistor T4, or the fifth transistor T5. The first initialization voltage and the second initialization voltage Vref2 are usually low levels, so that the threshold voltages of the third transistor T3, the fourth transistor T4, or the fifth transistor T5 will not have a negative bias phenomenon, but a positive bias phenomenon will occur, reducing the difficulty of turning on the transistor, thereby reducing the power consumption of the pixel driving circuit and increasing the service life. When multiplexing the first initialization voltage or the second initialization voltage Vref2 in the pixel driving circuit as the first modulation voltage, it is possible to avoid setting additional signal lines, reduce the number of signal lines, and lower the process difficulty.

[0052] Optionally, Figure 11 is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention, Figure 11 shown, the low voltage signal VGL of the gate driving circuit is multiplexed as the first modulation voltage V1.

[0053] Among them, the display panel further includes a gate driving circuit, which is connected to the gate lines and used to output gate driving signals to the gate lines. The gate driving signals are used to drive the transistors. The gate driving circuit includes multiple gate driving signals. The low-voltage signal VGL in the gate driving circuit is multiplexed as the first modulation voltage V1, so that the transistors of the first double-gate structure connected to the low-voltage signal VGL can be normally turned on during the turn-on process, avoiding the negative bias phenomenon of the threshold voltage, reducing the power consumption of the pixel driving circuit, ensuring the normal display of the display panel, and at the same time avoiding the additional setting of signal lines and reducing the manufacturing process difficulty.

[0054] Optionally, Figure 12 FIG. is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 12 As shown, the second transistor T2 adopts a second double-gate structure; the second double-gate structure includes a control terminal and a second bottom gate electrode 1002; the second bottom gate electrode 1002 is used to access the second modulation voltage V2 to make the threshold voltage of the second transistor T2 in a negatively biased state.

[0055] Among them, the data writing module 105 includes the second transistor T2. The second transistor T2 is set as a second double-gate structure, and the second bottom gate electrode 1002 of the second transistor T2 is connected to the second modulation voltage V2. The second modulation voltage V2 can be a fixed voltage signal. Since the threshold voltage of the second transistor T2 is prone to positive bias under the influence of heat, light or electricity, resulting in a four-screen phenomenon, in this embodiment, the second modulation voltage V2 is set to be a positive voltage signal to make the threshold voltage of the second transistor T2 in a negatively biased state, avoiding the abnormal turn-on of the second transistor T2, and thus improving the four-screen problem and ensuring the display effect of the display panel.

[0056] Optionally, the second modulation voltage V2 is greater than 3V.

[0057] Among them, for the second transistor T2 that is in the off state for a long time, the second modulation voltage V2 serves to increase the deviation of the threshold voltage in the second transistor T2, making it difficult for the second transistor T2 to turn on. By connecting the second bottom gate electrode 1002 in the second transistor T2 with a second double-gate structure to a second modulation voltage V2 greater than 3V, a negative bias phenomenon occurs in the threshold voltage of the second transistor T2, avoiding the abnormal turn-on of the second transistor T2, and thus improving the four-screen phenomenon.

[0058] Optionally, Figure 13 FIG. is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 13 As shown, the high-voltage signal VGH of the gate driving circuit is multiplexed as the second modulation voltage V2.

[0059] Among them, the gate driving circuit includes multiple gate driving voltage signals. To ensure the negative bias phenomenon of the threshold voltage in the second transistor T2, a high-voltage signal VGH in the gate driving circuit can be connected to the second bottom gate electrode 1002 of the second transistor T2, and the high-voltage signal VGH is multiplexed as the second modulation voltage V2, thereby ensuring the negative bias phenomenon of the threshold voltage in the second transistor T2, improving the four-screen splitting phenomenon, ensuring the normal display of the display panel, and at the same time, without the need to additionally set signal lines, reducing the number of signal lines set, and reducing the process difficulty. In addition, the second modulation voltage V2 can also be a signal such as PVDD.

[0060] Optionally, Figure 14 is a schematic structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 14 As shown, both the control end of the second transistor T2 and the second bottom gate electrode 1002 are connected to the second scan signal line.

[0061] Among them, the signal Sn on the second scan signal line is generally at a high level, and the second transistor T2 is in an off state for a long time, that is, in a negative bias state of the threshold voltage, and it is not easy to conduct to introduce the data signal Vdata. However, when the second transistor T2 conducts instantaneously, the threshold voltage of the second transistor T2 is not negatively biased, resulting in the easy conduction of the second transistor T2, and thus the four-screen splitting phenomenon can be improved, and the display effect of the display panel can be ensured.

[0062] Based on the same inventive concept, an embodiment of the present invention further provides a display panel. The display panel 200 includes the pixel driving circuit described in any one of the above embodiments. The display panel has the same or similar beneficial effects as the above pixel driving circuit, and will not be elaborated here.

[0063] Figure 15 is a schematic structural diagram of a display device provided by an embodiment of the present invention. As Figure 15 shown, the display device 300 includes the display panel 200 described in the above embodiment.

[0064] It should be noted that since the display device provided in this embodiment has the same or corresponding beneficial effects as the display panel of the above embodiment, it will not be elaborated here. The display device 300 provided by the embodiment of the present invention can be Figure 15 the mobile phone shown, or any electronic product with a display function, including but not limited to the following categories: television, notebook computer, desktop display, tablet computer, digital camera, smart bracelet, smart glasses, vehicle-mounted display, medical device, industrial control device, touch interaction terminal, etc. The embodiment of the present invention does not make special limitations on this.

[0065] Note that the above is only a preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A pixel driving circuit, characterized in that, Including: A driving module, a first initialization module, a storage module, a threshold compensation module, a data writing module, and a light-emitting module; The first end of the driving module is used for inputting a signal from a first power supply input; the second end of the driving module is used for providing a light-emitting driving signal to the light-emitting module; The storage module is connected between the control end of the driving module and the first end of the driving module; the threshold compensation module is connected between the control end of the driving module and the second end of the driving module; The data writing module is connected to the first end of the driving module and is used for transmitting a data voltage to the driving module; the first initialization module is connected between a first reference voltage output terminal and the control end of the driving module and is used for providing a first initialization voltage to the driving module; At least one of the transistors in the driving module, the first initialization module, and the threshold compensation module adopts a first double-gate structure; the transistor adopting the first double-gate structure includes a control end and a first bottom gate electrode; the first bottom gate electrode is used for accessing a first modulation voltage; The first adjustment voltage is a signal input from a first power supply, a signal output from a second power supply connected to the light-emitting module, a first reference voltage output from a first reference voltage output terminal, a high-voltage signal, or a low-voltage signal.

2. The pixel driving circuit according to claim 1, wherein The transistor of the threshold compensation module adopts the first double-gate structure.

3. The pixel driving circuit according to claim 1, wherein The transistor of the first initialization module adopts the first double-gate structure.

4. The pixel driving circuit according to claim 1, wherein The first modulation voltage is less than or equal to 3V.

5. The pixel driving circuit according to claim 4, wherein The first modulation voltage is less than or equal to 0V.

6. The pixel driving circuit according to claim 5, wherein The first initialization voltage is multiplexed as the first modulation voltage.

7. The pixel driving circuit according to claim 1, wherein Further including: A second initialization module; The second initialization module is connected between a second reference voltage output terminal and the first end of the light-emitting module and is used for providing a second initialization voltage to the light-emitting module.

8. The pixel driving circuit according to claim 7, wherein, Further including: A first light-emitting control module and a second light-emitting control module; The first light-emitting control module is connected between the first power supply and the first end of the driving module; The second light-emitting control module is connected between the second end of the driving module and the first end of the light-emitting module, and the second end of the light-emitting module is connected to a second power supply.

9. The pixel driving circuit according to claim 8, wherein The storage module includes a first capacitor; the first light-emitting control module includes a first transistor; the data writing module includes a second transistor; the driving module includes a third transistor; the threshold compensation module includes a fourth transistor; the first initialization module includes a fifth transistor; the second light-emitting control module includes a sixth transistor; the second initialization module includes a seventh transistor; The control end of the third transistor is respectively connected to the second end of the fifth transistor and the first end of the fourth transistor; the first end of the third transistor is connected to the second end of the first transistor; the first end of the first transistor is connected to the first power supply; the second end of the third transistor is respectively connected to the second end of the fourth transistor and the first end of the sixth transistor; the second end of the sixth transistor is connected to the first end of the light-emitting module; A first end of the fifth transistor is connected to the first reference voltage output terminal; a first end of the second transistor is connected to the data signal line; a second end of the second transistor is connected to a first end of the third transistor; a first end of the seventh transistor is connected to the second reference voltage output terminal; a second end of the seventh transistor is connected to a first end of the light-emitting module; At least one of the third transistor, the fourth transistor, and the fifth transistor adopts a first double-gate structure; control terminals of the first transistor and the sixth transistor are connected to a light-emitting control signal line; a control terminal of the fifth transistor is connected to a first scan signal line; control terminals of the fourth transistor, the second transistor, and the seventh transistor are connected to a second scan signal line.

10. The pixel driving circuit according to claim 7, wherein The first initialization voltage or the second initialization voltage is multiplexed as the first modulation voltage.

11. The pixel driving circuit according to claim 1, wherein A low-voltage signal of the gate driving circuit is multiplexed as the first modulation voltage.

12. The pixel driving circuit according to claim 9, wherein, The second transistor adopts a second double-gate structure; the second double-gate structure includes a control terminal and a second bottom gate electrode; the second bottom gate electrode is used to receive a second modulation voltage so that a threshold voltage of the second transistor is in a negative bias state.

13. The pixel driving circuit according to claim 12, wherein, The second modulation voltage is greater than 3V.

14. The pixel driving circuit according to claim 13, wherein A high-voltage signal of the gate driving circuit is multiplexed as the second modulation voltage.

15. The pixel driving circuit according to claim 12, characterized in that, Both the control terminal and the second bottom gate electrode of the second transistor are connected to the second scan signal line.

16. A display panel, characterized in that, Comprising the pixel driving circuit according to any one of claims 1-15 above.

17. A display device, characterized in that, Comprising the display panel according to claim 16 above.

Images