Pixel circuit, driving method thereof and display panel

Abstract

The invention discloses a pixel circuit, a driving method thereof and a display panel. The pixel circuit comprises a driving module, a light-emitting module, a light-emitting control module and a threshold compensation module, the light-emitting module, the light-emitting control module and the driving module are sequentially connected between the first power supply and the second power supply; the threshold compensation module is connected between the first control end of the driving module and the first end of the driving module, the second control end of the driving module is connected with adjusting voltage so as to adjust the threshold voltage of the driving module, and the threshold compensation module is used for compensating the adjusted threshold voltage of the driving module. According to the technical scheme, the display effect of the display panel is improved.

Description

Technical Field

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

[0002] With the rapid development of display technology, the application of display products using organic light emitting devices (OLED) is becoming more and more widespread.

[0003] However, the display performance of current OLED display panels needs to be improved. Summary of the invention

[0004] The present invention provides a pixel circuit and a driving method thereof, and a display panel, so as to improve the display performance of the display panel.

[0005] According to one aspect of the present invention, a pixel circuit is provided, the pixel circuit comprising: a driving module, a light emitting module, a light emitting control module and a threshold compensation module;

[0006] The light emitting module, the light emitting control module and the driving module are sequentially connected between the first power supply and the second power supply;

[0007] The threshold compensation module is connected between the first control terminal of the driving module and the first terminal of the driving module. The second control terminal of the driving module is connected to the regulating voltage to regulate the threshold voltage of the driving module. The threshold compensation module is used to compensate for the threshold voltage adjusted by the driving module.

[0008] Optionally, the pixel circuit further includes a data writing module and a storage module;

[0009] The first end of the data writing module is connected to the data line, and the second end of the data writing module and the first end of the storage module are connected to a first node; the control end of the data writing module is connected to the first scan line, and the data writing module is used to transmit the data voltage on the data line to the first node in the reset stage and the compensation stage;

[0010] The second end of the storage module is connected to the first control end of the driving module, and the storage module is used to couple the data voltage to the first control end of the driving module during the data writing phase; and store the voltage difference between the first control end of the driving module and the second end of the driving module;

[0011] Preferably, the control end of the threshold compensation module is connected to the second scan line, and the first scan line is multiplexed as the second scan line.

[0012] Optionally, the driving module includes a driving transistor, a first gate of the driving transistor is connected to the threshold compensation module, a second gate of the driving transistor is connected to the regulating voltage, a first electrode of the driving transistor is connected to the light emitting control module, and a second electrode of the driving transistor is connected to the second power supply;

[0013] Preferably, the regulation voltage is a global control voltage;

[0014] Preferably, the first gate is one of a bottom gate and a top gate, and the second gate is the other of the bottom gate and the top gate;

[0015] Preferably, the driving transistor is an N-type transistor;

[0016] Preferably, the driving transistor is an oxide transistor.

[0017] Optionally, the pixel circuit further includes a reset module;

[0018] The reset module is connected between the first power supply and the first end of the light control module, and the control end of the reset module is connected to the third scan line; the reset module is used to transmit the first power supply voltage provided by the first power supply to the first end of the light control module during the reset stage;

[0019] The light emitting module is connected between the first power source and the first end of the light emitting control module;

[0020] The second end of the light-emitting control module is connected to the first end of the driving module; the second end of the driving module is connected to the second power supply; the control end of the light-emitting control module is connected to the first light-emitting control line; the light-emitting control module is used to transmit the first power supply voltage to the first end of the driving module during the reset stage;

[0021] The threshold compensation module is used to transmit the first power supply voltage to the first control terminal of the driving module during the reset phase; and to compensate the threshold voltage adjusted by the driving module during the compensation phase;

[0022] Preferably, the compensation phase is after the reset phase;

[0023] Preferably, the pixel circuit further includes a data writing module, a control end of the data writing module is connected to the first scan line, a control end of the threshold compensation module is connected to the second scan line, and the first scan line is multiplexed into the second scan line and the third scan line.

[0024] Optionally, the pixel circuit further includes a transmission module;

[0025] The transmission module is connected between the first node and the second power supply, and the control end of the transmission module is connected to the second light-emitting control line; the transmission module is used to transmit the second power supply voltage provided by the second power supply to the first node during the data writing phase;

[0026] Preferably, the control end of the light-emitting control module is connected to a first light-emitting control line; a first light-emitting control signal on the first light-emitting control line has the same waveform as a second light-emitting control signal on the second light-emitting control line, and a starting time of an invalid level of the first light-emitting control signal is delayed relative to a starting time of an invalid level of the second light-emitting control signal.

[0027] Optionally, the threshold compensation module includes a threshold compensation transistor;

[0028] The control electrode of the threshold compensation transistor is connected to the second scan line, and the threshold compensation transistor is connected between the first control terminal of the driving module and the first terminal of the driving module;

[0029] Preferably, the light emitting control module comprises a light emitting control transistor, a control electrode of the light emitting control transistor is connected to the first light emitting control line, a first electrode of the light emitting control transistor is connected to the light emitting module, and a second electrode of the light emitting control transistor is connected to the first end of the driving module;

[0030] Preferably, the reset module comprises a reset transistor, the reset transistor is connected between the first power supply and the first end of the light emitting control module, and the control electrode of the reset transistor is connected to the third scan line.

[0031] Optionally, the data writing module includes a data writing transistor;

[0032] A first electrode of the data writing transistor is connected to the data line, a second electrode of the data writing transistor is connected to the first end of the storage module, and a control electrode of the data writing transistor is connected to the first scanning line;

[0033] Preferably, the transmission module comprises a transmission transistor, the transmission transistor is connected between the first node and the second power supply, and the control end of the transmission transistor is connected to the second light emitting control line;

[0034] Preferably, the storage module comprises a storage capacitor, a first electrode of the storage capacitor is connected to the second end of the data writing module, and a second electrode of the storage capacitor is connected to the first control end of the driving module.

[0035] According to another aspect of the present invention, a driving method of a pixel circuit is provided, wherein the pixel circuit comprises: a driving module, a light emitting module, a light emitting control module and a threshold compensation module; the light emitting module, the light emitting control module and the driving module are sequentially connected between a first power supply and a second power supply; the threshold compensation module is connected between a first control terminal of the driving module and a first terminal of the driving module, and a second control terminal of the driving module is connected to a regulating voltage;

[0036] The driving method of the pixel circuit includes:

[0037] In the compensation stage, the threshold compensation module compensates the threshold voltage adjusted by the driving module.

[0038] Optionally, the pixel circuit further includes a data writing module and a storage module;

[0039] The first end of the data writing module is connected to the data line, the second end of the data writing module and the first end of the storage module are connected to a first node; the control end of the data writing module is connected to the first scan line; the second end of the storage module is connected to the first control end of the driving module; the driving method of the pixel circuit also includes:

[0040] In the reset phase and the compensation phase, the data writing module transmits the data voltage on the data line to the first node;

[0041] In the data writing phase, the storage module couples the data voltage to the first control terminal of the driving module;

[0042] Preferably, the pixel circuit further includes a reset module;

[0043] The reset module is connected between the first power supply and the first end of the light emitting control module, and the control end of the reset module is connected to the third scanning line; the driving method of the pixel circuit also includes:

[0044] In the reset stage, the reset module transmits the first power supply voltage provided by the first power supply to the first control terminal of the driving module through the light emitting control module and the threshold compensation module;

[0045] Preferably, after the data writing stage, the driving method of the pixel circuit further includes:

[0046] In the light-emitting stage, the light-emitting control module controls the driving module to generate a driving current, and the light-emitting module emits light in response to the driving current;

[0047] Preferably, the driving module includes a driving transistor; before the reset stage, the driving method of the pixel circuit further includes:

[0048] determining the regulated voltage;

[0049] Preferably, the regulation voltage is a global control voltage.

[0050] According to another aspect of the present invention, a display panel is provided. The display panel includes the pixel circuit described in any embodiment of the present invention.

[0051] The technical solution of the embodiment of the present invention can adjust the threshold voltage of the driving module by connecting the regulating voltage to the second control terminal of the driving module. When the characteristic of the driving module changes due to process error or use, so that the threshold voltage of the driving module in a part of the pixel circuits is a positive voltage and the threshold voltage of the driving module in another part of the pixel circuits is a negative voltage, the threshold voltage of all the driving modules can be adjusted to a positive voltage or a negative voltage, that is, the threshold voltage of the driving module in all the pixel circuits is the same. In this way, after the threshold compensation module performs threshold compensation on the driving module, the consistency of the compensation can be improved, so that the threshold compensation effect of the driving modules of different pixel circuits is consistent, so that under the same gray scale, the driving current generated by different driving modules is the same, so that under the same gray scale, the luminous brightness of different light-emitting modules is the same, and the display uniformity of the display panel formed by the pixel circuit is improved, thereby improving the display performance of the display panel, that is, improving the use performance of the display panel.

[0052] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0054] Figure 1 is a structural schematic diagram of a pixel circuit provided by an embodiment of the present invention;

[0055] Figure 2 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0056] Figure 3 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0057] Figure 4is a current variation curve diagram of a driving transistor provided by an embodiment of the present invention;

[0058] Figure 5 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0059] Figure 6 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0060] Figure 7 is a timing diagram of a pixel circuit provided by an embodiment of the present invention;

[0061] Figure 8 is a timing diagram of a pixel circuit provided by an embodiment of the present invention;

[0062] Fig. 9 is a flow chart of a driving method of a pixel circuit provided by an embodiment of the present invention;

[0063] Fig.10 is a flow chart of another method for driving a pixel circuit provided by an embodiment of the present invention;

[0064] Fig.11 It is a schematic diagram of the structure of a display panel provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0065] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0066] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0067] As mentioned in the background technology, the existing display panel has the problem that the display performance needs to be improved. The inventor has found that the reason for this problem is that the active organic light-emitting diode display panel needs to be driven by current to emit light. The display panel includes a pixel circuit and an organic light-emitting diode. The pixel circuit includes a thin film transistor. The thin film transistor may include a switching transistor and a driving transistor. The switching transistor can control whether to write a data voltage to the driving transistor, control whether the driving current generated by the driving transistor is transmitted to the light-emitting diode, etc., thereby controlling the working timing of the pixel circuit. The driving transistor can generate a driving current according to the data voltage, so that the organic light-emitting diode emits light in response to the driving current. However, the characteristics of the thin film transistors in different pixel circuits may be different, especially when the characteristics of the driving transistors are different, such as when the threshold voltages of different driving transistors are different, the driving currents generated by different pixel circuits under the same gray scale will be different, so that the light emitting brightness of different light-emitting diodes under the same gray scale is different, resulting in uneven picture quality, affecting the display effect of the display panel, and making the display performance of the display panel poor.

[0068] In view of the above technical problem, an embodiment of the present invention provides a pixel circuit. Figure 1 is a schematic diagram of a pixel circuit provided by an embodiment of the present invention, with reference to Figure 1 , the pixel circuit includes: a driving module 110, a light emitting module 120, a light emitting control module 130 and a threshold compensation module 140;

[0069] The light emitting module 120, the light emitting control module 130 and the driving module 110 are sequentially connected between a first power source VDD and a second power source VSS;

[0070] The threshold compensation module 140 is connected between the first control terminal tg of the driving module 110 and the first terminal d of the driving module 110. The second control terminal bg of the driving module 110 is connected to the adjustment voltage V1 to adjust the threshold voltage of the driving module 110. The threshold compensation module 140 is used to compensate for the adjusted threshold voltage of the driving module 110.

[0071] Among them, the light-emitting module 120 may include an organic light-emitting diode. For example, the first power supply voltage provided by the first power supply VDD is a positive voltage, and the second power supply voltage provided by the second power supply VSS is a zero or negative voltage; or, the first power supply voltage provided by the first power supply VDD is a zero or negative voltage, and the second power supply voltage provided by the second power supply VSS is a positive voltage, which is not limited in this embodiment. The driving module 110 can generate a driving current, and the light-emitting module 120 can emit light in response to the driving current. The light-emitting control module 130 can control whether the driving current generated by the driving module 110 is transmitted to the light-emitting module 120. When the light-emitting control module 130 is turned on, the first power supply VDD, the light-emitting module 120, the light-emitting control module 130, the driving module 110 and the second power supply VSS can form a current path, so that the driving module 110 generates a driving current, thereby making the light-emitting module 120 emit light. Exemplarily, the light-emitting module 120, the light-emitting control module 130 and the driving module 110 are connected in series between the first power supply VDD and the second power supply VSS.

[0072] Specifically, the second control terminal bg of the driving module 110 is connected to the regulating voltage V1, and the regulating voltage V1 can adjust the voltage difference between the second control terminal bg of the driving module 110 and the second terminal of the driving module 110, so that the regulating voltage V1 can adjust the threshold voltage of the driving module 110. For example, the threshold voltage of the driving module 110 is adjusted to a positive voltage or a negative voltage, so that the threshold compensation module 140 can compensate the threshold voltage of the driving module 110. In this way, the driving current generated by the driving module 110 is independent of the threshold voltage of the driving module 110, so that the problem of driving current fluctuation caused by the threshold voltage drift of the driving module 110 can be avoided, and the light-emitting module 120 can be ensured to emit light stably, thereby improving the display effect of the display panel formed by the pixel circuit. In addition, the problem of uneven display caused by different threshold voltage offsets of different driving modules 110 can be avoided, so that the driving currents generated by different driving modules 110 tend to be consistent under the same gray scale, so that the light-emitting brightness of different light-emitting modules 120 is consistent, and the display uniformity of the display panel formed by the pixel circuit is improved.

[0073] For example, the second power supply voltage Vss provided by the second power supply VSS is a negative voltage or zero, and the second terminal s of the driving module 110 is connected to the second power supply VSS. For example, the threshold voltage Vth of the driving module 110 is adjusted to a positive voltage, that is, the voltage of the first control terminal tg of the driving module 110 is greater than the voltage of the second terminal of the driving module 110, and the driving module 110 is turned on. When the threshold compensation module 140 and the driving module 110 are turned on, the voltage of the first control terminal tg of the driving module 110 is the same as the voltage of the first terminal d of the driving module 110, and the first control terminal tg of the driving module 110 can be discharged to the second terminal s (the second power supply VSS) of the driving module 110 until the potential of the first control terminal tg of the driving module 110 is Vtg=Vss+Vth, so that the threshold compensation module 140 transmits the voltage related to the threshold voltage of the driving module 110 to the first control terminal tg of the driving module 110, and the threshold compensation of the driving module 110 is realized.

[0074] Furthermore, by adjusting the threshold voltage of the driving module 110, the threshold voltage of the driving module 110 in all pixel circuits is made the same, which facilitates improving the consistency of compensation and makes the threshold compensation effects of the driving modules 110 of different pixel circuits consistent. Therefore, at the same gray scale, the driving currents generated by different driving modules 110 are the same, so that at the same gray scale, the luminous brightness of different light-emitting modules 120 is the same, thereby improving the display uniformity of the display panel formed by the pixel circuit, thereby improving the display performance of the display panel, that is, improving the performance of the display panel.

[0075] The technical solution of this embodiment can adjust the threshold voltage of the driving module by connecting the regulating voltage to the second control terminal of the driving module. When the characteristic change of the driving module caused by process error or use makes the threshold voltage of the driving module in a part of the pixel circuits a positive voltage and the threshold voltage of the driving module in another part of the pixel circuits a negative voltage, the threshold voltage of all the driving modules can be adjusted to a positive voltage or a negative voltage, that is, the threshold voltage of the driving module in all the pixel circuits is the same. In this way, after the threshold compensation module performs threshold compensation on the driving module, the consistency of compensation can be improved, so that the threshold compensation effect of the driving modules of different pixel circuits is consistent, so that under the same gray scale, the driving current generated by different driving modules is the same, so that under the same gray scale, the luminous brightness of different light-emitting modules is the same, which improves the display uniformity of the display panel formed by the pixel circuit, thereby improving the display performance of the display panel, that is, improving the use performance of the display panel.

[0076] Based on the above technical solutions, possible structures of the pixel circuit are described below, but are not intended to limit the present application.

[0077] Figure 2is a schematic diagram of a structure of another pixel circuit provided by an embodiment of the present invention. Figure 2 , the pixel circuit further includes a data writing module 150 and a storage module 160;

[0078] The first end of the data writing module 150 is connected to the data line Data, and the second end of the data writing module 150 and the first end of the storage module 160 are connected to the first node n; the control end of the data writing module 150 is connected to the first scan line S1, and the data writing module 150 is used to transmit the data voltage Vdata on the data line to the first node n in the reset stage and the compensation stage;

[0079] The second end of the storage module 160 is connected to the first control end tg of the driving module 110. The storage module 160 is used to couple the data voltage Vdata to the first control end tg of the driving module 110 during the data writing phase; and store the voltage difference between the first control end tg of the driving module 110 and the second end s of the driving module 110.

[0080] Specifically, in the reset phase, the first scan signal on the first scan line S1 controls the data writing module 150 to be turned on, and the data writing module 150 transmits the data voltage Vdata to the first node n, and the potential of the first node n is Vn=Vdata. In the compensation phase, the data writing module 150 continues to transmit the data voltage Vdata to the first node n, and the voltage of the first node n can be maintained, so that the voltage of the first end of the storage module 160 remains unchanged, so that the storage module 160 discharges to the second power supply VSS through the threshold compensation module 140 and the driving module 110, so that the voltage of the second end of the storage module 160 changes, that is, the first control terminal tg of the driving module 110 changes, until the potential of the first control terminal tg of the driving module 110 is Vtg=Vss+Vth, so that the threshold compensation module 140 transmits the voltage related to the threshold voltage of the driving module 110 to the first control terminal tg of the driving module 110, and the threshold compensation of the driving module 110 is realized.

[0081] In the data writing stage, the storage module 160 can couple the data voltage Vdata to the first control terminal tg of the driving module 110 to write data to the driving module 110, so that the driving module 110 generates a driving current according to the data voltage in the light emitting stage, so that the light emitting module 120 emits light in response to the driving current. In addition, after the data is written, the storage module 160 can store the voltage difference Vtgs between the first control terminal tg of the driving module 110 and the second terminal s of the driving module 110, so as to maintain the driving current generated by the driving module 110, so that the driving module 110 can stably generate the driving current, and then the light emitting module 120 can stably emit light.

[0082] Optionally, refer to Figure 2 , the control end of the threshold compensation module 140 is connected to the second scan line S2, and the first scan line S1 is multiplexed as the second scan line S2.

[0083] Specifically, the display panel includes a shift register, and the shift register includes a plurality of gate drive circuits connected in cascade, and the gate drive circuit can output a scan signal. By setting the first scan line S1 to be multiplexed as the second scan line S2, the first scan signal on the first scan line S1 can be multiplexed as the second scan signal on the second scan line S2, the number of scan lines can be reduced, and the number of scan signals can be reduced, thereby reducing the number of shift registers in the display panel corresponding to the pixel circuit, thereby reducing the size of the non-display area or the frame area of ​​the display panel, and facilitating the realization of a narrow frame.

[0084] Based on the above technical solutions, Figure 3 is a schematic diagram of a structure of another pixel circuit provided by an embodiment of the present invention. Figure 3 The driving module 110 includes a driving transistor T1, a first gate of the driving transistor T1 is connected to the threshold compensation module 140, a second gate of the driving transistor T1 is connected to the adjustment voltage V1, a first electrode of the driving transistor T1 is connected to the light emitting control module 130, and a second electrode of the driving transistor T1 is connected to the second power supply VSS.

[0085] Specifically, the first gate of the driving transistor T1 is the first control terminal tg of the driving module 110, and the second gate of the driving transistor T1 is the second control terminal bg of the driving module 110. The first electrode of the driving transistor T1 is the first terminal d of the driving module 110, and the second electrode of the driving transistor T1 is the second terminal s of the driving module 110. The first electrode d of the driving transistor T1 is the drain, and the second electrode s of the driving transistor T1 is the source; or, the first electrode d of the driving transistor T1 is the source, and the second electrode s of the driving transistor T1 is the drain, which is not limited in this embodiment.

[0086] The second gate bg of the driving transistor T1 is connected to the regulating voltage V1, and the regulating voltage V1 can adjust the voltage difference between the second gate bg of the driving transistor T1 and the second electrode of the driving transistor T1, so that the regulating voltage V1 can adjust the threshold voltage of the driving transistor T1. For example, the threshold voltage of the driving transistor T1 is adjusted to a positive voltage or a negative voltage, so that the threshold compensation module 140 can compensate the threshold voltage of the driving transistor T1. The threshold voltage of the driving transistor T1 in all pixel circuits is the same, which is convenient for improving the consistency of compensation, so that the threshold compensation effect of the driving transistor T1 of different pixel circuits is consistent.

[0087] Optionally, the driving transistor T1 is turned on in response to the first level, and the adjustment voltage V1 is a voltage corresponding to the second level. The first level is different from the second level. The first level is a high level and the second level is a low level; or the first level is a low level and the second level is a high level. When the first level is a high level, the driving transistor T1 is turned on in response to the high level, and the threshold voltage of the driving transistor T1 is adjusted by setting the low-level adjustment voltage V1. The threshold voltage of the driving transistor T1 is inversely proportional to the adjustment voltage V1, so that the threshold voltage of the driving transistor T1 becomes a positive voltage, so that the threshold voltages of all driving transistors T1 are consistent, which is convenient for improving the consistency of the compensation effect.

[0088] Optionally, the driving transistor T1 is an N-type transistor, and the adjustment voltage V1 is a negative voltage. In this way, the threshold voltage of all driving transistors T1 can be adjusted to a positive voltage, so that when the driving transistor T1 is turned on, the first gate tg of the driving transistor T1 discharges to the second pole s (second power supply VSS) of the driving transistor T1 through the threshold compensation module 140 and the driving transistor T1, thereby achieving threshold compensation for the driving module 110. In addition, the uniformity of the compensation effect can be improved, so that the threshold compensation effect of the driving modules 110 of different pixel circuits is consistent. Optionally, the driving transistor T1 is an oxide transistor.

[0089] For example, Figure 4 is a current variation curve diagram of a driving transistor provided by an embodiment of the present invention, such as Figure 4 As shown, the horizontal axis is the voltage difference Vtgs between the first gate tg of the driving transistor T1 and the second electrode s of the driving transistor T1, and the vertical axis is the driving current I of the driving transistor T1. Different curves correspond to different voltage differences Vbgs between the second gate bg of the driving transistor T1 and the second electrode s of the driving transistor T1. Figure 4 As shown, when the voltage difference Vtgs between the first gate tg of the driving transistor T1 and the second electrode s of the driving transistor T1 is the same, the larger the voltage difference Vbgs between the second gate bg of the driving transistor T1 and the second electrode s of the driving transistor T1, the larger the driving current I, that is, the smaller the threshold voltage Vth, that is, the threshold voltage of the driving transistor T1 is inversely proportional to the adjustment voltage V1. Therefore, the adjustment voltage V1 can be determined according to the threshold voltage that needs to be adjusted for the driving transistor T1, so as to make the threshold voltages of all driving transistors T1 consistent, thereby improving the consistency of the compensation effect, and further improving the display uniformity of the display panel.

[0090] in, Figure 4The voltage difference between the first electrode d and the second electrode s of the driving transistor T1 corresponding to different curves is the same, which is 5.1 V. The length of the channel region of the driving transistor T1 corresponding to different curves is the same, which is 10 μm. The width of the channel region of the driving transistor T1 corresponding to different curves is the same, which is 20 μm.

[0091] Optionally, the adjustment voltage V1 is a global control voltage, that is, the second gates bg of the driving transistors T1 of all pixel circuits in the display panel are connected to the adjustment voltage V1, so that the threshold voltages of all driving transistors T1 are consistent, thereby improving the consistency of the compensation effect.

[0092] Optionally, the first gate tg is one of the bottom gate and the top gate, and the second gate bg is the other of the bottom gate and the top gate, that is, the first gate tg is the top gate, and the second gate bg is the bottom gate; or the first gate tg is the bottom gate, and the second gate bg is the top gate.

[0093] On the basis of the above technical solutions, optionally, refer to Figure 2 , the pixel circuit further includes a reset module 170;

[0094] The reset module 170 is connected between the first power source VDD and the first end of the light control module 130, and the control end of the reset module 170 is connected to the third scan line S3; the reset module 170 is used to transmit the first power supply voltage provided by the first power source VDD to the first end of the light control module 130 during the reset phase;

[0095] The light emitting module 120 is connected between the first power source VDD and the first end of the light emitting control module 130;

[0096] The second end of the light control module 130 is connected to the first end d of the driving module 110; the second end s of the driving module 110 is connected to the second power supply VSS; the control end of the light control module 130 is connected to the first light control line EM1; the light control module 130 is used to transmit the first power supply voltage to the first end d of the driving module 110 in the reset stage;

[0097] The threshold compensation module 140 is used to transmit the first power supply voltage to the first control terminal tg of the driving module 110 during the reset phase, and to compensate for the threshold voltage adjusted by the driving module 110 during the compensation phase.

[0098] Specifically, in the reset stage, the reset module 170 is turned on in response to the third scan signal on the third scan line S3, and the light-emitting control module 130 and the threshold compensation module 140 are turned on, so that the reset module 170 transmits the first power supply voltage Vdd provided by the first power supply VDD to the first control terminal tg of the driving module 110 through the light-emitting control module 130 and the threshold compensation module 140, and resets the first control terminal tg of the driving module 110, so that the potential of the first control terminal tg of the driving module 110 is Vtg=Vdd.

[0099] Optionally, the compensation phase follows the reset phase.

[0100] Specifically, in the reset stage, the reset module 170 transmits the first power supply voltage Vdd provided by the first power supply VDD to the first control terminal tg of the driving module 110, so that the driving module 110 is turned on. Therefore, in the compensation stage, the storage module 160 can discharge to the second power supply VSS through the driving module 110, so that the voltage of the second end of the storage module 160 reaches Vss+Vth, that is, the voltage of the first control terminal tg of the driving module 110 is Vss+Vth, thereby realizing threshold compensation for the driving module 110.

[0101] Optionally, refer to Figure 2 The pixel circuit further includes a data writing module 150, a control end of the data writing module 150 is connected to the first scanning line S1, a control end of the threshold compensation module 140 is connected to the second scanning line S2, and the first scanning line S1 is multiplexed into the second scanning line S2 and the third scanning line S3. In this way, the first scanning signal on the first scanning line S1 can be multiplexed into the second scanning signal and the third scanning signal, which can reduce the number of scanning signals, thereby reducing the number of shift registers in the display panel corresponding to the pixel circuit, thereby reducing the size of the non-display area or the frame area of ​​the display panel, and facilitating the realization of a narrow frame.

[0102] On the basis of the above technical solutions, optionally, refer to Figure 2 , the pixel circuit further includes a transmission module 180;

[0103] The transmission module 180 is connected between the first node n and the second power source VSS, and the control end of the transmission module 180 is connected to the second light-emitting control line EM2; the transmission module 180 is used to transmit the second power supply voltage Vss provided by the second power source VSS to the first node n during the data writing stage.

[0104] Specifically, in the compensation stage, the data writing module 150 transmits the data voltage Vdata on the data line Data to the first node n, so that the potential of the first node n is Vn=Vdata, and the potential of the second end of the storage module 160 can reach Vss+Vth. In the data writing stage, the transmission module 180 is turned on in response to the second light emitting control signal on the second light emitting control line EM2, and transmits the second power supply voltage Vss to the first node n, so that the voltage of the first end of the storage module 160 is Vn=Vss, and the voltage change of the first end of the storage module 160 is Vdata-Vss. The storage module 160 couples the data voltage Vdata to the second end of the storage module 160, and the voltage of the second end of the storage module 160 is Vss+Vth+(Vdata-Vss), that is, Vdata+Vth. In this way, the data voltage is written to the first control terminal tg of the driving module 110. Furthermore, the transmission module 180 is turned on, so that the second terminal s of the driving module 110 is turned on with the first node n, so that the storage module 160 can store the voltage difference Vtgs between the first control terminal tg of the driving module 110 and the second terminal s of the driving module 110, so as to maintain the driving current generated by the driving module 110. In the light-emitting stage, the driving current generated by the driving module 110 is That is Wherein, μ is the electron mobility of the driving transistor T1 in the driving module 110 , Cox is the channel capacitance per unit area of ​​the driving transistor T1 , W is the channel width of the driving transistor T1 , L is the channel length of the driving transistor T1 , and Vth is the threshold voltage of the driving transistor T1 .

[0105] In this way, the driving current generated by the driving module 110 is independent of the threshold voltage Vth of the driving module 110 and the first power source VDD. Therefore, the problem of driving current fluctuation caused by the threshold voltage offset of the driving module 110 can be avoided, and the driving current fluctuation caused by the voltage drop of the first power source VDD can be avoided, so that the stability of the driving current can be ensured, and then the light-emitting module 120 can be ensured to emit light stably, and the display effect of the display panel formed by the pixel circuit can be improved.

[0106] Furthermore, by providing the transmission module 180, after the compensation phase, the transmission module 180 is turned on, and the storage module 160 will couple the data voltage to the first control terminal tg of the driving module 110. In this way, the compensation phase can be separated from the data writing phase, so that the duration of the compensation phase is not limited by the data writing duration, and the compensation time can be adjusted according to demand, so that a larger range of threshold voltage fluctuations can be compensated, more sufficient compensation can be achieved, and a better compensation effect can be achieved.

[0107] Optionally, refer to Figure 2, the control end of the light-emitting control module 130 is connected to the first light-emitting control line EM1; the first light-emitting control signal on the first light-emitting control line EM1 has the same waveform as the second light-emitting control signal on the second light-emitting control line EM2, and the starting time of the invalid level of the first light-emitting control signal is delayed relative to the starting time of the invalid level of the second light-emitting control signal. For example, the starting time of the invalid level of the first light-emitting control signal is delayed by one line time relative to the starting time of the invalid level of the second light-emitting control signal. In this way, the first light-emitting control signal and the second light-emitting control signal can be provided by gate driving circuits of different levels in the same shift register. For example, the m-th level gate driving circuit outputs the second light-emitting control signal corresponding to the m-th row pixel circuit; the m+1-th level gate driving circuit outputs the second light-emitting control signal corresponding to the m+1-th row pixel circuit, which is also the first light-emitting control signal corresponding to the m-th row pixel circuit; or, the m-1-th level gate driving circuit outputs the second light-emitting control signal corresponding to the m-th row pixel circuit; the m-th level gate driving circuit outputs the second light-emitting control signal corresponding to the m+1-th row pixel circuit, which is also the first light-emitting control signal corresponding to the m-th row pixel circuit. The first light emitting control line EM1 and the second light emitting control line EM2 can be connected to the same shift register, thereby reducing the number of shift registers, which is beneficial to reducing the frame size.

[0108] In this way, the pixel circuit provided by the embodiment of the present invention may only require two groups of shift registers, which is helpful to reduce the frame size.

[0109] Among them, one line time can be calculated according to the resolution and refresh rate of the display panel. According to the resolution, the number of rows of pixel circuits (that is, the number of rows of light-emitting elements) can be determined. Then, one line time is

[0110]

[0111] Based on the above technical solutions, the structures that may be included in each module are described below, but this is not intended to limit the present application.

[0112] Figure 5 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention, Figure 6 is a schematic diagram of a structure of another pixel circuit provided by an embodiment of the present invention. Figure 5 or Figure 6 , the threshold compensation module 140 includes a threshold compensation transistor T2;

[0113] The control electrode of the threshold compensation transistor T2 is connected to the second scan line S2 , and the threshold compensation transistor T2 is connected between the first control terminal tg of the driving module 110 and the first terminal d of the driving module 110 .

[0114] Specifically, in the reset stage, when the threshold compensation transistor T2 is turned on in response to the second scan signal on the second scan line S2, the threshold compensation transistor T2 can transmit the first power supply voltage transmitted to the first electrode d of the driving transistor T1 by the reset module 170 and the light emitting control module 130 to the first gate tg of the driving transistor T1, reset the first gate tg of the driving transistor T1, and control the driving module 110 to be turned on. In the compensation stage, the storage module 160 discharges to the second power supply VSS through the threshold compensation transistor T2 and the driving transistor T1, so that the potential of the first gate tg of the driving transistor T1 reaches Vss+Vth, thereby realizing the threshold compensation of the driving transistor T1. Wherein, Vth is the threshold voltage of the driving transistor T1. Figure 4 The figure shows the case where the threshold compensation transistor T2 is an N-type transistor. Figure 5 The case where the threshold compensation transistor T2 is a P-type transistor is shown in FIG. 1 , and the present application does not limit the type of the threshold compensation transistor T2 .

[0115] Optionally, refer to Figure 5 or Figure 6 The light control module 130 includes a light control transistor T3, a control electrode of the light control transistor T3 is connected to the first light control line EM1, a first electrode of the light control transistor T3 is connected to the light emitting module 120, and a second electrode of the light control transistor T3 is connected to the first end d of the driving module 110.

[0116] Specifically, in the reset stage, the light-emitting control transistor T3 is turned on in response to the first light-emitting control signal on the first light-emitting control line EM1, so that the light-emitting control transistor T3 can transmit the first power supply voltage transmitted by the reset module 170 to the first gate tg of the driving transistor T1 through the threshold compensation transistor T2, thereby resetting the first gate tg. In the light-emitting stage, the light-emitting control transistor T3 is turned on, so that the first power supply VDD, the light-emitting module 120, the light-emitting control transistor T3, the driving transistor T1 and the second power supply VSS form a current path, so that the driving current generated by the driving transistor T1 is transmitted to the light-emitting module 120, so that the light-emitting module 120 emits light in response to the driving current.

[0117] Figure 5 FIG. 4 shows the case where the light emitting control transistor T3 is an N-type transistor. Figure 6 The case where the light emitting control transistor T3 is a P-type transistor is shown in the figure, and the present application does not limit the type of the light emitting control transistor T3.

[0118] Optionally, refer to Figure 5 or Figure 6The reset module 170 includes a reset transistor T4, which is connected between the first power supply VDD and the first end of the light emitting control module 130, and the control electrode of the reset transistor T4 is connected to the third scan line S3.

[0119] Specifically, in the reset stage, the reset transistor T4 is turned on in response to the third scan signal on the third scan line S3, so that the reset transistor T4 transmits the first power supply voltage provided by the first power supply VDD to the first gate tg of the driving transistor T1 through the light emitting control transistor T3 and the threshold compensation transistor T2, thereby resetting the first gate tg and controlling the driving transistor T1 to be turned on, thereby facilitating the subsequent threshold compensation of the driving transistor T1.

[0120] Figure 5 The figure shows the case where the reset transistor T4 is an N-type transistor. Figure 6 The case where the reset transistor T4 is a P-type transistor is shown in FIG. 1 , and the present application does not limit the type of the reset transistor T4 .

[0121] Optionally, refer to Figure 5 or Figure 6 , the data writing module 150 includes a data writing transistor T5;

[0122] A first electrode of the data writing transistor T5 is connected to the data line Data, a second electrode of the data writing transistor T5 is connected to a first end of the storage module 160 , and a control electrode of the data writing transistor T5 is connected to the first scanning line S1 .

[0123] Specifically, in the reset phase, the data write transistor T5 is turned on in response to the first scan line signal on the first scan line S1, and the data write transistor T5 transmits the data voltage on the data line Data to the first node n. In the compensation phase, the data write transistor T5 continues to transmit the data voltage on the data line Data to the first node n, thereby maintaining the potential of the first end of the storage module 160, so that after the storage module 160 is discharged, the potential of the second end of the storage module 160 reaches Vss+Vth, thereby achieving threshold compensation for the driving transistor T1. In addition, in the data write phase, the storage module 160 couples the data voltage to the first gate tg of the driving transistor T1, so that the driving transistor T1 can generate a driving current according to the data voltage.

[0124] Figure 5 FIG. 4 shows the case where the data writing transistor T5 is an N-type transistor. Figure 6 The case where the data writing transistor T5 is a P-type transistor is shown in FIG. 1 , and the present application does not limit the type of the data writing transistor T5 .

[0125] Optionally, refer to Figure 5 or Figure 6The transmission module 180 includes a transmission transistor T6, which is connected between the first node n and the second power supply VSS, and a control end of the transmission transistor T6 is connected to the second light emitting control line EM2.

[0126] Specifically, in the data writing stage, the transmission transistor T6 is turned on in response to the second light-emitting control signal on the second light-emitting control line EM2, and the transmission transistor T6 transmits the second power supply voltage Vss provided by the second power supply VSS to the first end of the storage module 160, so that the potential of the second end of the storage module 160 also changes accordingly, thereby coupling and transmitting the data voltage to the first gate tg of the driving transistor T1.

[0127] Figure 5 FIG. 4 shows the case where the transmission transistor T6 is an N-type transistor. Figure 6 The case where the transmission transistor T6 is a P-type transistor is shown in FIG. 1 , and the present application does not limit the type of the transmission transistor T6 .

[0128] Figure 5 FIG. 4 shows a case where all transistors are N-type transistors. Using N-type transistors can reduce the leakage current of the driving transistor T1. Figure 6 The figure shows the case where all transistors except the driving transistor T1 are P-type transistors. The use of P-type transistors can reduce power consumption and reduce the area occupied by the pixel circuit, which is convenient for the display panel to achieve a higher pixel density. In some other implementations, some of the transistors in the pixel circuit can be N-type transistors and the other part can be P-type transistors, which is not limited in this embodiment.

[0129] Optionally, refer to Figure 5 or Figure 6 The storage module 160 includes a storage capacitor C1, a first electrode of the storage capacitor C1 is connected to the second end of the data writing module 150, and a second electrode of the storage capacitor C1 is connected to the first control end tg of the driving module 110.

[0130] Specifically, the storage capacitor C1 can couple the data voltage to the first gate tg of the driving transistor T1 during the data writing phase, so that the driving transistor T1 generates a driving current according to the data voltage. In addition, the storage capacitor C1 can store the voltage difference Vtgs between the first gate tg of the driving transistor T1 and the second electrode s of the driving transistor T1, so as to maintain the driving current generated by the driving transistor T1, so that the driving transistor T1 stably generates the driving current, thereby improving the light emitting stability of the light emitting module 120.

[0131] Optionally, refer to Figure 5 or Figure 6The light emitting module 120 includes an organic light emitting diode D1, wherein a first pole of the organic light emitting diode D1 is a first end of the light emitting module 120, and a second pole of the organic light emitting diode D1 is a second end of the light emitting module 120. The first pole of the organic light emitting diode D1 is an anode, and the second pole of the organic light emitting diode D1 is a cathode; or, the first pole of the organic light emitting diode D1 is a cathode, and the second pole of the organic light emitting diode D1 is an anode.

[0132] The working process of the pixel circuit is described below in conjunction with the working timing of the pixel circuit, but it is not intended to limit the present application.

[0133] For example, the first scan line S1 is multiplexed into the second scan line S2 and the third scan line S3 , that is, the first scan signal, the second scan signal and the third scan signal are the same scan signal Scan.

[0134] In one embodiment, Figure 7 is a timing diagram of a pixel circuit provided by an embodiment of the present invention. Optionally, refer to Figure 5 and Figure 7 ,The working process of the pixel circuit includes the following stages.

[0135] In the reset phase t1, the scan signal Scan is at a high level, the data write transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are turned on, the first light-emitting control signal Em1 is at a high level, the light-emitting control transistor T3 is turned on, the second light-emitting control signal Em2 is at a low level, and the transmission transistor T6 is not turned on. The data write transistor T5 transmits the data voltage on the data line Data to the first node n, and the potential of the first node n is Vn=Vdata. The reset transistor T4 transmits the first power supply voltage Vdd provided by the first power supply VDD to the first gate tg of the driving transistor T1 through the light-emitting control transistor T3 and the threshold compensation transistor T2, thereby resetting the first gate tg. The voltage of the first gate tg is Vtg=Vdd, which can control the driving transistor T1 to be turned on.

[0136] In the compensation stage t2, the scan signal Scan is at a high level, the data writing transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are turned on, the first light emitting control signal Em1 and the second light emitting control signal Em2 are at a low level, and the light emitting control transistor T3 and the transmission transistor T6 are not turned on. The data writing transistor T5 continues to transmit the data voltage on the data line Data to the first node n, thereby maintaining the potential of the first electrode of the storage capacitor C1, so that the storage capacitor C1 is discharged to the second power supply VSS through the threshold compensation transistor T2 and the driving transistor T1, until the potential of the first gate tg of the driving transistor T1 is Vtg=Vss+Vth, so that the threshold compensation transistor T2 transmits the voltage related to the threshold voltage of the driving transistor T1 to the first control terminal tg of the driving transistor T1, and threshold compensation is performed on the driving transistor T1.

[0137] In the data writing stage t3, the first light emitting control signal Em1 and the scanning signal Scan are at a low level, and the light emitting control transistor T3, the data writing transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are not turned on. The second light emitting control signal Em2 is at a high level, and the transmission transistor T6 is turned on. The transmission transistor T6 transmits the second power supply voltage Vss to the first node n, so that the voltage of the first electrode of the storage capacitor C1 is Vn=Vss, and the voltage change of the first electrode of the storage capacitor C1 is Vdata-Vss. The storage capacitor C1 couples the data voltage Vdata to the second electrode of the storage capacitor C1, and the voltage of the second electrode of the storage capacitor C1 is Vss+Vth+(Vdata-Vss), that is, Vdata+Vth. In this way, the data voltage is written to the first gate tg of the driving transistor T1.

[0138] In the light-emitting stage t4, the scan signal Scan is at a low level, the data writing transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are not turned on, the first light-emitting control signal Em1 and the second light-emitting control signal Em2 are at a high level, and the light-emitting control transistor T3 and the transmission transistor T6 are turned on. The transmission transistor T6 is turned on, and the voltage of the first electrode of the storage capacitor C1 can be maintained at Vn=Vss, so that the voltage of the second electrode of the storage capacitor C1 is still Vdata+Vth. The light-emitting control transistor T3 is turned on, so that the first power supply VDD, the light-emitting module 120, the light-emitting control transistor T3, the driving transistor T1 and the second power supply VSS form a current path, and the driving current generated by the driving transistor T1 is That is In this way, the driving current generated by the driving transistor T1 is independent of the threshold voltage Vth of the driving transistor T1 and the first power source VDD. Therefore, the problem of driving current fluctuation caused by the threshold voltage offset of the driving transistor T1 can be avoided, and the driving current fluctuation caused by the voltage drop of the first power source VDD can be avoided, so that the stability of the driving current can be ensured, and then the light-emitting module 120 can be ensured to emit light stably, and the display effect of the display panel formed by the pixel circuit can be improved.

[0139] In another embodiment, Figure 8 is a timing diagram of a pixel circuit provided by an embodiment of the present invention. Optionally, refer to Figure 6 and Figure 8 ,The working process of the pixel circuit includes the following stages.

[0140] In the reset phase t1, the scan signal Scan is at a low level, the data write transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are turned on, the first light-emitting control signal Em1 is at a low level, the light-emitting control transistor T3 is turned on, the second light-emitting control signal Em2 is at a high level, and the transmission transistor T6 is not turned on. The data write transistor T5 transmits the data voltage on the data line Data to the first node n, and the potential of the first node n is Vn=Vdata. The reset transistor T4 transmits the first power supply voltage Vdd provided by the first power supply VDD to the first gate tg of the driving transistor T1 through the light-emitting control transistor T3 and the threshold compensation transistor T2, thereby resetting the first gate tg. The voltage of the first gate tg is Vtg=Vdd, which can control the driving transistor T1 to be turned on.

[0141] In the compensation stage t2, the scan signal Scan is at a low level, the data writing transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are turned on, the first light emitting control signal Em1 and the second light emitting control signal Em2 are at a high level, and the light emitting control transistor T3 and the transmission transistor T6 are not turned on. The data writing transistor T5 continues to transmit the data voltage on the data line Data to the first node n, thereby maintaining the potential of the first electrode of the storage capacitor C1, so that the storage capacitor C1 is discharged to the second power supply VSS through the threshold compensation transistor T2 and the driving transistor T1, until the potential of the first gate tg of the driving transistor T1 is Vtg=Vss+Vth, so that the threshold compensation transistor T2 transmits the voltage related to the threshold voltage of the driving transistor T1 to the first control terminal tg of the driving transistor T1, and threshold compensation is performed on the driving transistor T1.

[0142] In the data writing stage t3, the first light emitting control signal Em1 and the scanning signal Scan are at a high level, and the light emitting control transistor T3, the data writing transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are not turned on. The second light emitting control signal Em2 is at a low level, and the transmission transistor T6 is turned on. The transmission transistor T6 transmits the second power supply voltage Vss to the first node n, so that the voltage of the first electrode of the storage capacitor C1 is Vn=Vss, and the voltage change of the first electrode of the storage capacitor C1 is Vdata-Vss. The storage capacitor C1 couples the data voltage Vdata to the second electrode of the storage capacitor C1, and the voltage of the second electrode of the storage capacitor C1 is Vss+Vth+(Vdata-Vss), that is, Vdata+Vth. In this way, the data voltage is written to the first gate tg of the driving transistor T1.

[0143] In the light-emitting stage t4, the scan signal Scan is at a high level, the data writing transistor T5, the reset transistor T4 and the threshold compensation transistor T2 are not turned on, the first light-emitting control signal Em1 and the second light-emitting control signal Em2 are at a low level, and the light-emitting control transistor T3 and the transmission transistor T6 are turned on. The transmission transistor T6 is turned on, and the voltage of the first electrode of the storage capacitor C1 can be maintained at Vn=Vss, so that the voltage of the second electrode of the storage capacitor C1 is still Vdata+Vth. The light-emitting control transistor T3 is turned on, so that the first power supply VDD, the light-emitting module 120, the light-emitting control transistor T3, the driving transistor T1 and the second power supply VSS form a current path, and the driving current generated by the driving transistor T1 is That is In this way, the driving current generated by the driving transistor T1 is independent of the threshold voltage Vth of the driving transistor T1 and the first power source VDD. Therefore, the problem of driving current fluctuation caused by the threshold voltage offset of the driving transistor T1 can be avoided, and the driving current fluctuation caused by the voltage drop of the first power source VDD can be avoided, so that the stability of the driving current can be ensured, and then the light-emitting module 120 can be ensured to emit light stably, and the display effect of the display panel formed by the pixel circuit can be improved.

[0144] An embodiment of the present invention further provides a method for driving a pixel circuit. The driving method is used to drive the pixel circuit provided by any embodiment of the present invention. Fig. 9 is a flowchart of a driving method of a pixel circuit provided by an embodiment of the present invention, with reference to Fig. 9 , the driving method of the pixel circuit includes:

[0145] S101 . In a compensation stage, a threshold compensation module compensates for a threshold voltage adjusted by a driving module.

[0146] Specifically, the regulating voltage V1 can adjust the voltage difference between the second control terminal bg of the driving module 110 and the second terminal of the driving module 110, so that the regulating voltage V1 can adjust the threshold voltage of the driving module 110, and the threshold voltage of all driving modules 110 can be adjusted to a positive voltage or a negative voltage, that is, the threshold voltage of the driving module 110 in all pixel circuits is the same. In this way, after the threshold compensation module 140 performs threshold compensation on the driving module 110, the consistency of compensation can be improved, so that the threshold compensation effect of the driving modules 110 of different pixel circuits is consistent, so that under the same gray scale, the driving currents generated by different driving modules 110 are the same, so that under the same gray scale, the luminous brightness of different light-emitting modules 120 is the same, which improves the display uniformity of the display panel formed by the pixel circuit, thereby improving the display performance of the display panel, that is, improving the use performance of the display panel.

[0147] S102 , in the light-emitting stage, the light-emitting control module controls the driving module to generate a driving current, and the light-emitting module emits light in response to the driving current.

[0148] Specifically, in the light-emitting stage, the light-emitting control module 130 is turned on, and the first power source VDD, the light-emitting module 120, the light-emitting control module 130, the driving module 110 and the second power source VSS can form a current path, so that the driving module 110 generates a driving current, thereby making the light-emitting module 120 emit light. And after the compensation stage, the driving current generated by the driving module 110 is independent of the threshold voltage of the driving module 110, so that the problem of driving current fluctuation caused by the threshold voltage offset of the driving module 110 can be avoided, and the light-emitting module 120 can be ensured to emit light stably, thereby improving the display effect of the display panel formed by the pixel circuit.

[0149] On the basis of the above technical solution, the driving method of the pixel circuit further includes:

[0150] In the reset phase and the compensation phase, the data writing module transmits the data voltage on the data line to the first node;

[0151] In the data writing phase, the storage module couples the data voltage to the first control terminal of the driving module.

[0152] Specifically, in the reset phase, the data writing module 150 transmits the data voltage Vdata on the data line Data to the first node n, so that the potential of the first node n is Vn=Vdata. In the compensation phase, the data writing module 150 continues to be turned on, maintaining the potential of the first node n as Vn=Vdata, so that the storage module 160 is discharged, so that the potential of the second end of the storage module 160 changes, that is, the potential of the first control terminal tg of the driving module 110 changes, thereby transmitting the threshold voltage of the driving module 110 to the first control terminal tg of the driving module 110. In the data writing phase, the transmission module 180 is turned on, and the storage module 160 couples the data voltage to the first control terminal tg of the driving module 110. In this way, the compensation phase can be separated from the data writing phase, so that the duration of the compensation phase is not limited by the data writing duration, and the compensation time can be adjusted according to demand, so that a larger range of threshold voltage fluctuations can be compensated, more sufficient compensation can be achieved, and a better compensation effect can be achieved.

[0153] Optionally, the pixel circuit further includes a reset module; the reset module is connected between the first power supply and the first end of the light emitting control module, and the control end of the reset module is connected to the third scanning line. Optionally, the driving method of the pixel circuit further includes:

[0154] In the reset stage, the reset module transmits the first power supply voltage provided by the first power supply to the first control terminal of the driving module through the light emitting control module and the threshold compensation module.

[0155] Specifically, in the reset stage, the reset module 170 is turned on, and the light emitting control module 130 and the threshold compensation module 140 are turned on, so that the reset module 170 transmits the first power supply voltage Vdd provided by the first power supply VDD to the first control terminal tg of the driving module 110 through the light emitting control module 130 and the threshold compensation module 140, and resets the first control terminal tg of the driving module 110, so that the potential of the first control terminal tg of the driving module 110 is Vtg=Vdd. This is convenient for controlling the driving module 110 to turn on, and for performing threshold compensation on the driving module 110 in the compensation stage.

[0156] Optionally, after the data writing stage, the driving method of the pixel circuit further includes:

[0157] In the light-emitting stage, the light-emitting control module controls the driving module to generate a driving current, and the light-emitting module emits light in response to the driving current.

[0158] In summary, Fig.10 is a flowchart of another method for driving a pixel circuit provided by an embodiment of the present invention. Optionally, refer to Fig.10 , the driving method of the pixel circuit includes:

[0159] S201. In the reset phase, the data writing module transmits the data voltage on the data line to the first node; the reset module transmits the first power supply voltage provided by the first power supply to the first control terminal of the driving module through the light emitting control module and the threshold compensation module.

[0160] S202 , in the compensation stage, the data writing module transmits the data voltage on the data line to the first node; the threshold compensation module compensates for the threshold voltage adjusted by the driving module.

[0161] S203 , in the data writing phase, the storage module couples the data voltage to the first control terminal of the driving module.

[0162] S204 , in the light-emitting stage, the light-emitting control module controls the driving module to generate a driving current, and the light-emitting module emits light in response to the driving current.

[0163] On the basis of the above technical solution, optionally, before the reset stage, the driving method of the pixel circuit further includes:

[0164] Determine the regulated voltage.

[0165] Specifically, the second gate bg of the driving transistor T1 is connected to the adjustment voltage V1, and the adjustment voltage V1 can adjust the voltage difference between the second gate bg of the driving transistor T1 and the second electrode of the driving transistor T1, so that the adjustment voltage V1 can adjust the threshold voltage of the driving transistor T1. Then the adjustment voltage can be determined according to the threshold voltage that the driving transistor T1 needs to reach, so as to facilitate the adjustment of the threshold voltage of the driving transistor T1 in the driving module 110, so that the threshold voltage of all driving transistors T1 is the same. For example, the threshold voltage of the driving transistor T1 is inversely proportional to the adjustment voltage. For example, if the threshold voltage of the driving transistor T1 needs to be adjusted to a positive voltage, the adjustment voltage is a negative voltage. For example, if the threshold voltage of the driving transistor T1 needs to be adjusted to a negative voltage, the adjustment voltage is a positive voltage. In this way, the threshold voltage of the driving transistor T1 in the driving module 110 can be adjusted according to demand, so that the threshold voltage of all driving transistors T1 is the same, and the uniformity of the threshold compensation is improved, so that under the same gray scale, the driving current generated by all driving transistors T1 is the same, and the luminous brightness of all light-emitting modules 120 is consistent, which improves the display uniformity of the display panel.

[0166] Optionally, the regulated voltage is a global control voltage.

[0167] The technical solution of the embodiment of the present invention further provides a display panel, Fig.11 is a schematic diagram of a display panel provided by an embodiment of the present invention, with reference to Fig.11The display panel includes the pixel circuit provided by any of the above embodiments. The display panel can be applied to mobile phones, tablets, displays, smart watches, MP3, MP4 or other wearable devices, etc., because it includes the pixel circuit provided by any embodiment of the present invention, and thus has the same beneficial effects, which will not be described in detail here.

[0168] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0169] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pixel circuit, characterized in that: include: A driving module, a light emitting module, a light emitting control module and a threshold compensation module; The light emitting module, the light emitting control module and the driving module are sequentially connected between the first power supply and the second power supply; The threshold compensation module is connected between the first control terminal of the driving module and the first terminal of the driving module. The second control terminal of the driving module is connected to the regulating voltage to regulate the threshold voltage of the driving module. The threshold compensation module is used to compensate for the threshold voltage adjusted by the driving module.

2. The pixel circuit according to claim 1, characterized in that: The pixel circuit also includes a data writing module and a storage module; The first end of the data writing module is connected to the data line, and the second end of the data writing module and the first end of the storage module are connected to a first node; the control end of the data writing module is connected to the first scan line, and the data writing module is used to transmit the data voltage on the data line to the first node in the reset stage and the compensation stage; The second end of the storage module is connected to the first control end of the driving module, and the storage module is used to couple the data voltage to the first control end of the driving module during the data writing phase; and storing a voltage difference between a first control terminal of the driving module and a second terminal of the driving module; Preferably, the control end of the threshold compensation module is connected to the second scan line, and the first scan line is multiplexed as the second scan line.

3. The pixel circuit according to claim 1, characterized in that: The driving module comprises a driving transistor, a first gate of the driving transistor is connected to the threshold compensation module, a second gate of the driving transistor is connected to the regulating voltage, a first electrode of the driving transistor is connected to the light emitting control module, and a second electrode of the driving transistor is connected to the second power supply; Preferably, the regulation voltage is a global control voltage; Preferably, the first gate is one of a bottom gate and a top gate, and the second gate is the other of the bottom gate and the top gate; Preferably, the driving transistor is an N-type transistor; Preferably, the driving transistor is an oxide transistor.

4. The pixel circuit according to any one of claims 1 to 3, characterized in that: The pixel circuit also includes a reset module; The reset module is connected between the first power supply and the first end of the light control module, and the control end of the reset module is connected to the third scan line; the reset module is used to transmit the first power supply voltage provided by the first power supply to the first end of the light control module during the reset stage; The light emitting module is connected between the first power source and the first end of the light emitting control module; The second end of the light emitting control module is connected to the first end of the driving module; the second end of the driving module is connected to the second power supply; the control end of the light emitting control module is connected to the first light emitting control line; The light emitting control module is used for transmitting the first power supply voltage to the first end of the driving module during the reset phase; The threshold compensation module is used to transmit the first power supply voltage to the first control terminal of the driving module during the reset phase; and to compensate the threshold voltage adjusted by the driving module during the compensation phase; Preferably, the compensation phase is after the reset phase; Preferably, the pixel circuit further includes a data writing module, a control end of the data writing module is connected to the first scan line, a control end of the threshold compensation module is connected to the second scan line, and the first scan line is multiplexed into the second scan line and the third scan line.

5. The pixel circuit according to claim 2, characterized in that: The pixel circuit also includes a transmission module; The transmission module is connected between the first node and the second power supply, and the control end of the transmission module is connected to the second light-emitting control line; the transmission module is used to transmit the second power supply voltage provided by the second power supply to the first node during the data writing phase; Preferably, the control end of the light emitting control module is connected to the first light emitting control line; The first light-emitting control signal on the first light-emitting control line has the same waveform as the second light-emitting control signal on the second light-emitting control line, and a starting time of an invalid level of the first light-emitting control signal is delayed relative to a starting time of an invalid level of the second light-emitting control signal.

6. The pixel circuit according to claim 4, characterized in that: The threshold compensation module includes a threshold compensation transistor; The control electrode of the threshold compensation transistor is connected to the second scan line, and the threshold compensation transistor is connected between the first control terminal of the driving module and the first terminal of the driving module; Preferably, the light emitting control module comprises a light emitting control transistor, a control electrode of the light emitting control transistor is connected to the first light emitting control line, a first electrode of the light emitting control transistor is connected to the light emitting module, and a second electrode of the light emitting control transistor is connected to the first end of the driving module; Preferably, the reset module comprises a reset transistor, the reset transistor is connected between the first power supply and the first end of the light emitting control module, and the control electrode of the reset transistor is connected to the third scan line.

7. The pixel circuit according to claim 5, characterized in that: The data writing module includes a data writing transistor; A first electrode of the data writing transistor is connected to the data line, a second electrode of the data writing transistor is connected to the first end of the storage module, and a control electrode of the data writing transistor is connected to the first scanning line; Preferably, the transmission module comprises a transmission transistor, the transmission transistor is connected between the first node and the second power supply, and the control end of the transmission transistor is connected to the second light emitting control line; Preferably, the storage module comprises a storage capacitor, a first electrode of the storage capacitor is connected to the second end of the data writing module, and a second electrode of the storage capacitor is connected to the first control end of the driving module.

8. A method for driving a pixel circuit, characterized in that: The pixel circuit comprises: a driving module, a light emitting module, a light emitting control module and a threshold compensation module; the light emitting module, the light emitting control module and the driving module are sequentially connected between a first power supply and a second power supply; the threshold compensation module is connected between a first control terminal of the driving module and a first terminal of the driving module, and a second control terminal of the driving module is connected to a regulating voltage; The driving method of the pixel circuit includes: In the compensation stage, the threshold compensation module compensates the threshold voltage adjusted by the driving module.

9. The driving method of the pixel circuit according to claim 8, characterized in that: The pixel circuit also includes a data writing module and a storage module; The first end of the data writing module is connected to the data line, the second end of the data writing module and the first end of the storage module are connected to a first node; the control end of the data writing module is connected to the first scan line; The second end of the storage module is connected to the first control end of the driving module; The driving method of the pixel circuit further includes: In the reset phase and the compensation phase, the data writing module transmits the data voltage on the data line to the first node; In the data writing phase, the storage module couples the data voltage to the first control terminal of the driving module; Preferably, the pixel circuit further includes a reset module; The reset module is connected between the first power supply and the first end of the light emitting control module, and the control end of the reset module is connected to the third scanning line; the driving method of the pixel circuit also includes: In the reset stage, the reset module transmits the first power supply voltage provided by the first power supply to the first control terminal of the driving module through the light emitting control module and the threshold compensation module; Preferably, after the data writing stage, the driving method of the pixel circuit further includes: In the light-emitting stage, the light-emitting control module controls the driving module to generate a driving current, and the light-emitting module emits light in response to the driving current; Preferably, the driving module includes a driving transistor; before the reset stage, the driving method of the pixel circuit further includes: determining the regulated voltage; Preferably, the regulation voltage is a global control voltage.

10. A display panel, characterized in that: The pixel circuit comprises the pixel circuit described in any one of claims 1 to 7.

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