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

Abstract

This invention discloses a pixel driving circuit and driving method, and a display panel. The pixel driving circuit's driving module receives a signal output from a first power supply and provides a light-emitting driving signal to the light-emitting element. A threshold compensation module, under the control of a second scan signal, connects to the control terminal and the second terminal of the driving module. A first capacitor's first terminal is connected to the first power supply; its second terminal is connected to the control terminal of the driving module. A data input module is connected to the first terminal of a second capacitor; the second terminal of the second capacitor is connected to the control terminal of the driving module. The data input module, under the control of the first scan signal, outputs a data signal to the first terminal of the second capacitor, or outputs a reference voltage to the first terminal of the second capacitor under the control of the second scan signal. A reset module outputs a reset voltage to the first terminal of the light-emitting element, the second terminal of the driving module, and the control terminal of the driving module. The technical solution provided by this invention can improve the uniformity of the panel display.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a pixel driving circuit and driving method, and a display panel. Background Technology

[0002] With the continuous development of electronic technology, the requirements for display screen effects are also getting higher and higher. OLED (Organic Light-Emitting Diode) screens have received widespread attention due to their advantages such as self-illumination, low power consumption, thinness, flexibility, vibrant colors, high contrast, and fast response speed. They are gradually replacing LCD (Liquid Crystal Display) screens and have become the representative of the next generation of displays.

[0003] Since OLED elements are current-driven devices, corresponding pixel driving circuits are required to provide driving current to enable the OLED elements to emit light. As display resolution gradually increases and pixel size decreases, the area occupied by the pixel driving circuit becomes smaller. Consequently, the capacitance value of the capacitors in the pixel driving circuit also decreases. When the scan signal flips from low to high, the effect of charge injection becomes more and more obvious, resulting in a more significant difference between far-end and near-end pixels, which leads to a deterioration in display uniformity. Summary of the Invention

[0004] This invention provides a pixel driving circuit and driving method, and a display panel to improve display uniformity.

[0005] In a first aspect, embodiments of the present invention provide a pixel driving circuit, including: a driving module, a threshold compensation module, a reset module, a data input module, a first capacitor, and a second capacitor;

[0006] The first terminal of the driving module is used to input the signal output by the first power supply; the second terminal of the driving module is used to provide a light-emitting driving signal to the light-emitting element; the threshold compensation module is used to connect the control terminal of the driving module and the second terminal of the driving module under the control of the second scan signal; the first terminal of the first capacitor is connected to the first power supply; the second terminal of the first capacitor is connected to the control terminal of the driving module.

[0007] The data input module is connected to the first terminal of the second capacitor; the second terminal of the second capacitor is connected to the control terminal of the drive module; the data input module is connected to the data signal and the reference voltage respectively, and is used to output the data signal to the first terminal of the second capacitor under the control of the first scan signal, or to output the reference voltage to the first terminal of the second capacitor under the control of the second scan signal.

[0008] The reset module is connected to the first end of the light-emitting element and is used to output a reset voltage to the first end of the light-emitting element, the second end of the driving module, and the control end of the driving module.

[0009] Secondly, embodiments of the present invention provide a driving method for a pixel driving circuit, applicable to any pixel driving circuit provided in embodiments of the present invention, wherein the pixel driving circuit further includes a light emission control module; the light emission control module is disposed between the second end of the driving module and the first end of the light emission element;

[0010] The driving method of the pixel driving circuit includes:

[0011] During the initialization phase, the reset module transmits the reset voltage to the first terminal of the light-emitting element; the light-emitting control module is in a first conducting state under the control of the light-emitting control signal, and is used to transmit the reset voltage to the second terminal of the driving module; the threshold compensation module transmits the reset voltage to the control terminal of the driving module; the data writing module transmits the reference voltage to the first terminal of the second capacitor under the control of the second scan signal.

[0012] During the threshold compensation phase, the threshold compensation module compensates the threshold voltage of the driving module to the control terminal of the driving module; the data writing module continues to transmit the reference voltage to the first terminal of the second capacitor under the control of the second scan signal.

[0013] During the data writing phase, the data writing module transmits the data signal to the first terminal of the second capacitor under the control of the first scan signal;

[0014] During the pre-stabilization phase, the light emission control module is in the second conduction state under the control of the light emission control signal; the reset module is turned on under the control of the reset control signal; and there is a connection between the first power supply and the reset voltage.

[0015] During the light-emitting stage, the light-emitting control module is in a second conduction state under the control of the light-emitting control signal, so that the driving module generates a driving current to be transmitted to the light-emitting element;

[0016] The conduction current of the light-emitting control module in the first conduction state is less than the conduction current of the light-emitting control module in the second conduction state.

[0017] Thirdly, embodiments of the present invention also provide a display panel, including the pixel driving circuit provided in any embodiment of the present invention.

[0018] In this invention, the driving module of the pixel driving circuit is connected to a first power supply to provide a light-emitting driving signal to the light-emitting element. The threshold compensation module is used to perform threshold compensation on the control terminal of the driving module. A first capacitor is connected between the control terminal and the first terminal of the driving module. The data input module is connected to the control terminal of the driving module through a second capacitor and outputs a data signal to the second capacitor under the control of the first scan signal. Under the control of the second scan signal, it outputs a reference voltage to the second capacitor. The threshold compensation module is connected to the control terminal and the second terminal of the driving module under the control of the second scan signal. In this embodiment, the second scan signal simultaneously controls the data input module and the threshold compensation module. Therefore, the control terminals of the data input module and the threshold compensation module experience voltage jumps simultaneously, and charge injection occurs simultaneously across the two ends of the second capacitor. This minimizes the impact of charge injection on the threshold compensation of the driving module's control terminal, resulting in the threshold voltage captured by the driving module's control terminal being closer to the driving module's own threshold voltage. Thus, the threshold voltage captured by the control terminal of both the near-end and far-end pixel driving circuits is less affected by charge injection and tends to be consistent, ensuring a small brightness difference between the light-emitting elements at the near and far ends of the display panel and a uniform display. Furthermore, the threshold voltage captured in this embodiment is closer to the actual threshold voltage of the driving module, thereby achieving a more complete threshold compensation function, improving the accuracy of brightness display, and enhancing the quality of screen display. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a pixel driving circuit provided in an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of another pixel driving circuit provided in an embodiment of the present invention;

[0021] Figure 3 for Figure 2 Timing diagram of the driving current of the middle pixel;

[0022] Figure 4 This is a schematic diagram of another pixel driving circuit provided in an embodiment of the present invention;

[0023] Figure 5 This is a comparative structural schematic diagram of a pixel driving circuit provided in an embodiment of the present invention;

[0024] Figure 6 for Figure 5 Timing diagram of the mid-pixel driving circuit;

[0025] Figure 7 A schematic flowchart of a pixel driving circuit driving method provided in an embodiment of the present invention;

[0026] Figure 8This is a schematic diagram of the structure of a display panel provided in an embodiment of the present invention. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0028] In pixel driving circuits, especially for high-resolution display panels, the capacitance values ​​of the capacitors are relatively small, making the impact of charge injection more significant. Specifically, when a signal transition occurs at the control terminal of a transistor in the pixel driving circuit—for example, from high to low or vice versa—a level transition easily occurs between the source and drain of that transistor (forming a miniature capacitor between the control terminal and the source or drain). This causes a change in the potential of certain nodes within the pixel driving circuit, effectively injecting charge into those nodes. Furthermore, because the control signal connected to the control terminal, such as the scan signal, has different voltage values ​​at the near and far ends, the amount of charge injected into the same nodes in the near and far pixel driving circuits differs. This results in different luminous currents driving the light-emitting elements, leading to a shift in brightness between the near and far ends of the light-emitting elements and consequently, a decrease in the uniformity of the display panel. It should be noted that the near end refers to the end closest to the driving circuit, while the far end is the end furthest from the driving circuit. Typically, various driving circuits such as data driving circuits and scanning driving circuits are set at one end of the display panel. The voltage values ​​for each driving circuit differ from the direction closest to the driving circuit to the direction furthest from the driving circuit.

[0029] To address the aforementioned charge injection problem, embodiments of the present invention provide a pixel driving circuit, such as... Figure 1 As shown, Figure 1 A schematic diagram of a pixel driving circuit provided in an embodiment of the present invention includes: a driving module 11, a threshold compensation module 12, a reset module 13, a data input module 14, a first capacitor C1, and a second capacitor C2;

[0030] The first terminal of the driving module 11 is used to input the signal output by the first power supply PVDD; the second terminal of the driving module 11 is used to provide a light-emitting driving signal for the light-emitting element D1; the threshold compensation module 12 is used to connect the control terminal of the driving module 11 and the second terminal of the driving module 11 under the control of the second scan signal SCAN2; the first terminal of the first capacitor C1 is connected to the first power supply PVDD; the second terminal of the first capacitor C1 is connected to the control terminal of the driving module 11.

[0031] The data input module 14 is connected to the first end of the second capacitor C2; the second end of the second capacitor C2 is connected to the control terminal of the drive module 11; the data input module 14 is connected to the data signal Vdata and the reference voltage Vofs respectively, and is used to output the data signal Vdata to the first end of the second capacitor C2 under the control of the first scan signal SCAN1, or to output the reference voltage Vofs to the first end of the second capacitor C2 under the control of the second scan signal SCAN2.

[0032] The reset module 13 is connected to the first terminal of the light-emitting element D1 and is used to output the reset voltage VRST to the first terminal of the light-emitting element D1, the second terminal of the drive module 11, and the control terminal of the drive module 11.

[0033] In this embodiment of the invention, the driving module of the pixel driving circuit is connected to a first power supply to provide a light-emitting driving signal to the light-emitting element. The threshold compensation module is used to perform threshold compensation on the control terminal of the driving module. A first capacitor is connected between the control terminal and the first terminal of the driving module. The data input module is connected to the control terminal of the driving module through a second capacitor and outputs a data signal to the second capacitor under the control of the first scan signal. Under the control of the second scan signal, it outputs a reference voltage to the second capacitor. The threshold compensation module is connected to the control terminal and the second terminal of the driving module under the control of the second scan signal. In this embodiment, the second scan signal simultaneously controls the data input module and the threshold compensation module. Therefore, the control terminals of the data input module and the threshold compensation module experience simultaneous voltage jumps, and charge injection occurs simultaneously across the two ends of the second capacitor. This minimizes the impact of charge injection on the threshold compensation of the control terminal of the driving module, resulting in the threshold voltage captured by the control terminal of the driving module being closer to the threshold voltage of the driving module itself. Thus, the threshold voltage captured by the control terminal of both the near-end and far-end pixel driving circuits tends to be consistent, ensuring a small brightness difference between the light-emitting elements at the near and far ends of the display panel and a uniform display. Furthermore, the threshold voltage captured in this embodiment is closer to the actual threshold voltage of the driving module, thereby achieving a more complete threshold compensation function, improving the accuracy of brightness display, and enhancing the quality of screen display.

[0034] The above is the core idea of ​​this invention. The technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0035] like Figure 1As shown, the driving module 11 includes a control terminal, a first terminal, and a second terminal. The node of the control terminal of the driving module 11 can be labeled as the first node N1, and the node of the second terminal as the second node N2. The first terminal of the driving module 11 is also used to connect to the first power supply PVDD. The second terminal of the driving module 11 is electrically connected to the first terminal (e.g., the anode) of the light-emitting element D1, and the second terminal of the light-emitting element D1 can be used to connect to the second power supply PVEE. Thus, the first power supply PVDD forms a conductive path through the driving module 11, the light-emitting element D1, and the second power supply PVEE. That is, the driving module 11 can provide a light-emitting driving signal to the light-emitting element D1, causing the light-emitting element D1 to generate a light-emitting current. The threshold compensation module 12 is used to connect the control terminal (first node N1) and the second terminal (second node N2) of the driving module 11, and is used to adjust the threshold voltage V at which the driving module 11 is turned on. thp Write to the control terminal of the driver module 11 to prevent it from affecting the light-emitting current of the light-emitting element D1 and improve the brightness display accuracy of the light-emitting element D1.

[0036] The first terminal of the first capacitor C1 is connected to the first power supply PVDD; the second terminal of the first capacitor C1 is connected to the first node N1; the first terminal of the second capacitor C2 (which can be referred to as the third node N3) is connected to the data input module 14; and the second terminal of the second capacitor C2 is connected to the first node N1. Furthermore, under the control of the first scan signal SCAN1, the data input module 14 outputs a data signal Vdata to the first terminal of the second capacitor C2, and under the control of the second scan signal SCAN2, outputs a reference voltage Vofs to the first terminal of the second capacitor C2. It should be noted that both the data input module 14 and the threshold compensation module 12 are controlled by the second scan signal SCAN2. Therefore, the control terminals of the data input module 14 and the threshold compensation module 12 will simultaneously undergo voltage transitions when voltage transitions occur. For example, when the second scan signal SCAN2 changes from low level to high level, or changes from high level to low level, the first parasitic capacitance Cgd1 formed between the data input module 14 and the first node N1 undergoes a voltage transition, the second parasitic capacitance Cgs2 formed between the threshold compensation module 12 and the first node N1 undergoes a voltage transition, and the third parasitic capacitance Cgd2 formed between the threshold compensation module 12 and the second node N2 undergoes a voltage transition. Because voltage jumps occur simultaneously at the first node N1 and the third node N3 on both sides of the second capacitor C2, the injected charge is dispersed within the capacitive network between the first node N1 and the third node N3 (including the first capacitor C1, the second capacitor C2, the first parasitic capacitor Cgd1, the second parasitic capacitor Cgs2, and the third parasitic capacitor Cgd2). Therefore, the amount of injected charge at the first node N1 is relatively small, and consequently, the potential of the first node N1 is less affected by the voltage jump. At this point, it can be seen that additional charge is still injected into the first node N1. However, since the charge injection occurs simultaneously at the first node N1 and the third node N3, the capacitive network formed between them generates current (charge flows) to some extent. This process effectively disperses the injected charge, minimizing the impact of the charge injection on the potential of the first node N1. Therefore, the impact of the charge injection is greatly weakened, resulting in a lower threshold voltage V captured by the first node N1. thpThis approach is closer to reality, and the threshold values ​​captured by the pixel driving circuits at each position are consistent, thus achieving a more perfect threshold voltage compensation function. In this embodiment, the second scan signal SCAN2 simultaneously controls the on and off states of the data input module 14 and the threshold compensation module 12. Therefore, although voltage jumps occur at the first node N1 and the third node N3, these jumps happen simultaneously, causing the injected charge to be dispersed. In contrast, in the prior art, because the data input module 14 and the threshold compensation module 12 are controlled by different scan signals with different timing sequences, the first node N1 and the third node N3 undergo time-sharing voltage jumps. During each voltage jump, charge injection occurs only on one side of the second capacitor C2. At this time, the first node N1 will superimpose the charge injections from the two jumps, causing the potential of the first node N1 to be significantly affected, ultimately impacting the threshold voltage V. thp Accuracy of capture. Specifically, when the control terminal of the threshold compensation module 12 experiences a voltage jump to ΔV1, the voltage of the first node N1 also jumps to ΔV1. Subsequently, when the control terminal of the data input module 14 experiences a voltage jump to ΔV2, the voltage of the first node N1 jumps to ΔV2 again. After two charge injections, the voltage transformation value of the first node N1 is (ΔV1 + ΔV2). That is, in the prior art, the control terminal voltages of the data input module 14 and the threshold compensation module 12 jump separately, causing the first node N1 to superimpose the two charge injection processes. However, in this embodiment of the invention, the control terminal voltages of the data input module 14 and the threshold compensation module 12 jump simultaneously, which disperses the single charge injection process of the first node N1. Therefore, compared with the prior art, the pixel driving circuit of this embodiment weakens the influence of charge injection. Even if the charge injection amounts of the near-end pixel driving circuit and the far-end pixel driving circuit are different, the difference in the first node N1 will not be too large, thus reducing the difference in the luminous current between the near-end pixel driving circuit and the far-end pixel driving circuit. In summary, the pixel driving circuit in this embodiment of the invention has higher display uniformity, effectively prevents random offset noise in the pixel driving circuit, and improves the display quality.

[0037] In addition, in this embodiment, the pixel driving circuit also includes a reset module 13. The reset module 13 is connected to the first end of the light-emitting element D1 and can transmit the reset voltage VRST to the first end of the light-emitting element D1. Furthermore, by controlling the on and off of modules such as the threshold compensation module 12, the reset module 13 can reset the second node N2 and the first node N1 to prevent the first node N1 from having residual voltage in the previous display cycle, which would affect the brightness display of the light-emitting element D1 in the current cycle.

[0038] Optionally, the pixel driving circuit may further include: an emissive control module 15; the emissive control module 15 is disposed between the second terminal of the driving module 11 and the first terminal of the emissive element D1. The emissive control module 15 can connect the second terminal of the driving module 11 and the first terminal of the emissive element D1, thereby controlling the emissive element D1 to emit light. Furthermore, when the reset module 13 resets the pixel driving circuit, the emissive control module 15 can be turned on, and the threshold compensation module 12 can also be turned on, so that the reset voltage VRST is transmitted to the second terminal of the driving module 11 and the control terminal of the driving module 11.

[0039] Based on the above embodiments, optionally, the pixel driving circuit is illustrated by taking the example where all modules are turned on at a low level. The operation of the pixel driving circuit includes at least the following: In the initialization phase, the reset module 13 is used to provide the reset voltage VRST to the first terminal of the light-emitting element D1 to reset the anode of the light-emitting element D1; the light-emitting control module 15 is used to be in the on state under the control of the light-emitting control signal EMIT to transmit the reset voltage VRST to the second node N2 to reset the second terminal of the driving module 11; the threshold compensation module 12 is used to convert the reset voltage VRST to a low level. ST is transmitted to the first node N1 to reset the second terminal of the first capacitor C1, the second terminal of the second capacitor C2, and the control terminal of the drive module 11. At this time, the drive module 11 is in the conducting state, changing the drive module 11 from the bias state of the previous drive cycle back to the initial state to prevent the hysteresis effect of the drive module 11 from affecting the subsequent working state of the drive module 11; the data input module 14 is used to transmit the reference voltage Vofs to the first terminal of the second capacitor C2, the potentials of the first node N1 and the second node N2 are the reset voltage VRST, and the voltage of the third node N3 is the reference voltage Vofs;

[0040] During the threshold compensation phase, the reset module 13 and the light-emitting control module 15 are turned off. At this time, a path is formed between the first power supply PVDD and the first node N1, allowing the current signal to charge the first node N1 sequentially through the driving module 11 and the threshold compensation module 12 via the first power supply PVDD. Initially, the potential of the first node N1 is low, and the driving module 11 is turned on, raising the potential of the second node N2. The threshold compensation module 12 is then turned on under the control of the second scan signal SCAN2, gradually increasing the potential of the first node N1. As the potential of the first node N1 increases, the current of the driving module 11 gradually decreases until the voltage difference between the first node N1 and the second node N2 is equal to the threshold voltage V of the driving module 11. thp At this time, the drive module 11 is turned off, and the potential Un1 of the first node N1 and the potential Un2 of the second node N2 are Un1 = Un2 = PVDD - V thpThis is the critical point at which the drive module 11 shuts down. Thus, at the end of the threshold compensation phase, the potential of the first node N1 is related to the threshold voltage of the drive module 11, realizing the process of the threshold compensation module 12 compensating the threshold voltage of the drive module 11 to the first node N1. The data input module 14 continues to transmit the reference voltage Vofs to the first terminal of the second capacitor C2, ensuring that the potential Un1 of the first node N1 is not coupled to the third node N3, and the potential Un3 of the third node N3 = V. ofs Thus, at the end of the threshold compensation phase T2, the voltage difference across the second capacitor C2 becomes Un1 - Vofs. It should be noted that at the end of the threshold compensation phase, the second scan signal SCAN2 suddenly changes from low to high, with the voltage jumping to ΔV1. The first node N1, the second node N2, and the third node N3 will simultaneously experience voltage jumps. Where C1 is the capacitance of the first capacitor; C2 is the capacitance of the second capacitor; Cot is the total capacitance generated by the capacitor network seen by the first node N1 and the third node N3, excluding C1 and C2; Un3 = V ofs +ΔV1; However, in existing technologies, when the first node N1 and the third node N3 experience voltage jumps ΔV1 and ΔV2 respectively, Un1′=Un2′=PVDD-V thp +ΔV+ΔV2; Comparing Un1′ in the prior art with Un1 in this embodiment, it can be found that in this embodiment, the first node N1 is less affected by charge injection, making its capture threshold voltage closer to V. thp The data input module 14 stops writing the reference voltage Vofs to the first terminal of the second capacitor C2. In this embodiment, the threshold voltage captured by both the near-end and far-end pixel driving circuits during the threshold compensation stage is less affected by charge injection. Therefore, regardless of the difference in the amount of charge injection, the final light-emitting current of the light-emitting element is not significantly different between the near-end and far-end pixel driving circuits, resulting in strong display uniformity. Furthermore, during the threshold compensation stage, the reset module 13 can be turned on to reset the first terminal of the light-emitting element D1, or it can be turned off. In this embodiment, the reset module 13 may include a process of changing from the on state to the off state.

[0041] During the data writing phase, the data input module 14 writes the data signal Vdata to the first terminal of the second capacitor C2, making the potential Un3 of the second terminal of the second capacitor C2, i.e., the third node N3, equal to Vdata. dataThat is, the potential at the second terminal of the second capacitor C2 changes (Vdata - Vofs); simultaneously, due to the coupling effect of the second capacitor C2, the potential of the first node N1, which is electrically connected to the second terminal of the second capacitor C2, will change accordingly; since the first node N1 is also electrically connected to the first capacitor C1, the amount of potential change of the first node N1 is related to the voltage division of the first node N1 by the first capacitor C1, therefore the potential of the first node N1... Thus, even though the data signal Vdata written to the third node N3 by the data writing module 11 is a relatively large voltage signal, the signal coupled to the first node N1 is positively correlated with the ratio of the capacitance value of the first capacitor C1 to the sum of the capacitance values ​​of the two capacitors (first capacitor C1 and second capacitor C2). This causes the first capacitor C1 and the second capacitor C2 to act as a voltage divider. Compared to the data signal Vdata written to the third node N3, the voltage change of the first node N1 is smaller, thereby allowing the data signal Vdata to be placed within a wider range to correspond one-to-one with each gray level in the 0-255 grayscale range. Consequently, at the end of the data writing process, the potential of the first node N1 can also correspond one-to-one with each gray level in the 0-255 grayscale range. Afterwards, under the control of the first scan signal SCAN1, the data writing module 11 stops outputting the data signal Vdata. The first scan signal SCAN1 changes from low level to high level, and the voltage jumps to ΔV2. Un3 = V data +ΔV2; During the data writing phase, the driver module 11, the light emission control module 15, the reset module 13, and the threshold compensation module 12 are all turned off.

[0042] During the light-emitting phase, the data input module 14, reset module 13, and threshold compensation module 12 are all turned off. The light-emitting control module 15 is turned on under the control of the light-emitting control signal EMIT, so that the driving module 11, based on the potential of the first node N1, generates a driving current Id that is transmitted to the light-emitting element D1, driving the light-emitting element D1 to emit light. Therefore, the light-emitting current of the light-emitting element in this embodiment... Where μ is the carrier mobility of the PMOS transistor; C OX Capacitance per unit area of ​​oxide layer; The width-to-length ratio of the PMOS transistor; |V thp | represents the threshold voltage of the PMOS transistor; V DS V is the source-drain voltage difference of the PMOS transistor; m is the mobility; V T It represents the absolute temperature coefficient.

[0043] Optionally, the operation of the pixel driving circuit described above may further include a pre-stabilization stage; the pre-stabilization stage can be set after the data writing stage and before the light emission stage. Specifically, in the pre-stabilization stage, the data input module 14 is turned off, and the driving module 11, the light emission control module 15, and the reset module 13 are turned on, forming a path between the first power supply PVDD terminal and the reset voltage VRST terminal. The pre-stabilization stage, following the data input stage, stabilizes the voltages of the first node N1 and the second node N2, providing a stable potential for the control terminal of the driving module 11 to stably drive the light-emitting element D1, further improving the light emission uniformity of the light-emitting element D1 and reducing the random offset noise of the pixel driving current.

[0044] Figure 2 This is a schematic diagram of another pixel driving circuit provided in an embodiment of the present invention. Figure 3 for Figure 2 Timing diagram of the mid-pixel driving circuit. (See diagram below.) Figure 3 As shown, the working timing of the pixel driving circuit includes, in sequence: initialization stage T1, threshold compensation stage T2, data writing stage T3, pre-stabilization stage T4, and light emission stage T5. Optionally, the data input module 14 may include: a first input unit 141 and a second input unit 142; the first input unit 141 is used to connect the data signal Vdata and the first terminal of the second capacitor C2 under the control of the first scan signal SCAN1; the second input unit 142 is used to connect the reference voltage Vofs and the first terminal of the second capacitor C2 under the control of the second scan signal SCAN2. The data input module 14 may include two parts: the first input unit 141 and the second input unit 142. The second input unit 142 is used to transmit the reference voltage Vofs to the first terminal of the second capacitor C2 during the initialization stage T1 and the threshold compensation stage T2, and the first input unit 141 is used to transmit the data signal Vdata to the first terminal of the second capacitor C2 during the data writing stage T3. It should be noted that, as Figure 3 As shown, since the enable levels of the first scan signal SCAN1 and the second scan signal SCAN2 do not overlap, the first input unit 141 and the second input unit 142 operate in a time-sharing manner, preventing the data signal Vdata and the reference voltage Vofs from being simultaneously transmitted to the first terminal of the second capacitor C2. It should be noted that in... Figure 3 In the embodiment shown, the low level of the first scan signal SCAN1 and the second scan signal SCAN2 is the enable level, and the high level is the disable level, but the present invention is not limited to this.

[0045] Optionally, the first input unit 141 may include a first transistor M1; the second input unit 142 may include a second transistor M2; the first terminal of the first transistor M1 is connected to the data signal Vdata; the second terminal of the first transistor M1 is connected to the first terminal of the second capacitor C2; the control terminal of the first transistor M1 is connected to the first scan signal SCAN1; the first terminal of the second transistor M2 is connected to the reference voltage Vofs; the second terminal of the second transistor M2 is connected to the first terminal of the second capacitor C2; and the control terminal of the second transistor M2 is connected to the second scan signal SCAN2.

[0046] Continue to refer to Figure 2 Optionally, the light-emitting control module 15 may include: a third transistor M3; the control terminal of the third transistor M3 is connected to the light-emitting control signal EMIT; the first terminal of the third transistor M3 is connected to the second terminal of the driving module 11; and the second terminal of the third transistor M3 is connected to the first terminal of the light-emitting element D1. The third transistor M3 is used to connect the driving module 11 and the light-emitting element D1. During the initialization phase, the driving module 11, the third transistor M3, and the reset module 13 are all turned on. The third transistor M3 transmits the reset voltage VRST to the second node N2, thereby resetting the control terminal and the second terminal of the driving module 11. During the pre-stabilization phase, the current flowing through the driving module 11 and the third transistor M3 forms a conductive path between the first power supply PVDD terminal and the reset voltage VRST terminal, stabilizing the potential of the control terminal and the second terminal of the driving module 11 to a voltage that can reach the corresponding grayscale current of the light-emitting element D1. During the light-emitting phase, the current flowing through the third transistor M3 forms a conductive path between the first power supply PVDD terminal, the light-emitting element D1, and the second power supply PVEE terminal, forming the corresponding grayscale current of the light-emitting element D1.

[0047] Figure 4 This is a schematic diagram of another pixel driving circuit provided in an embodiment of the present invention. Figure 4 The timing sequence of the middle pixel driving circuit is as follows Figure 3The working timing is as follows. Optionally, the pixel driving circuit may also include: a negative feedback module 16; the first end of the negative feedback module 16 is connected to the first power supply PVDD; the second end of the negative feedback module 16 is connected to the first end of the driving module 11; the control end of the negative feedback module 16 is connected to the second end of the negative feedback module 16. During the light emission stage, the resistance of the cathode (output second power supply PVEE) is large and not uniform due to different gray levels. This causes the second power supply PVEE of the pixel driving circuit to fluctuate at different positions. The fluctuation of the second power supply PVEE will cause the voltage of the second node N2 to fluctuate. In addition, during the display process, many factors can cause the voltage of the second node N2 to fluctuate. Here, we only take the fluctuation of the second power supply PVEE causing the voltage fluctuation of the second node N2 as an example. It is known that the transistor of the driving module 11 in the display is operating in the subthreshold region. Therefore, when the source-drain voltage difference of the transistor (the voltage difference between the first segment and the second end of the driving module 11) fluctuates, the light emission current will be affected and fluctuate. This causes the display brightness to change and the display uniformity to deteriorate. In this embodiment, a negative feedback module 16 is added to the pixel driving circuit. The negative feedback module 16 is used to effectively suppress the fluctuation of the light-emitting current when the voltage of the second node N2 fluctuates, and pull the light-emitting current back to the gray-scale current corresponding to the light-emitting element D1, thereby further improving the display uniformity and reducing the random offset noise of the pixel driving current.

[0048] For details, please refer to [link / reference]. Figure 4 Optionally, the negative feedback module 16 may include: a fourth transistor M4; the first terminal of the fourth transistor M4 is connected to the first power supply PVDD; the second terminal of the fourth transistor M4 is connected to the first terminal of the driving module 11; and the control terminal of the fourth transistor M4 is connected to the second terminal of the fourth transistor M4. With the addition of the fourth transistor M4 to the pixel circuit, when the second power supply PVEE increases, the voltage of the second node N2 increases accordingly, thus increasing the luminous current I of the light-emitting element D1. OLED Decrease, while when the luminous current I OLED When the current decreases, in order to match the current emitted by the fourth transistor M4, the voltage V at the second terminal (fourth node NF) of the fourth transistor M4... NF It will also increase, at which point the voltage V between the control terminal and the first terminal of the drive module 11 will rise. GS As the voltage increases, the luminous current generated by the driving module 11 increases, thus shifting the offset luminous current I. OLED The original value is pulled back to restore the light-emitting element D1 to the same brightness; and when the second power supply PVEE decreases, the voltage of the second node N2 decreases accordingly, so the light-emitting current I of the light-emitting element D1 increases. OLED Increase, while when the luminous current I OLED When the current increases, the voltage V at the fourth node NF of the fourth transistor M4 needs to be adjusted to match the current.NF It will also decrease, at which point the voltage difference V between the control terminal and the first terminal of the drive module 11 will decrease. GS As the emission decreases, the resulting luminous current decreases, thus shifting the luminous current I. OLED The original value is restored, bringing the light-emitting element D1 back to the same brightness. In summary, the fourth transistor M4 effectively suppresses the difference in light-emitting current caused by junction voltage fluctuations, further improving display uniformity.

[0049] Continue to refer to Figure 2 and Figure 4 Optionally, the driving module 11 may include a fifth transistor M5; the threshold compensation module 12 includes a sixth transistor M6; the reset module 13 includes a seventh transistor M7; the control terminal of the fifth transistor M5 is connected to the second terminal of the first capacitor C1 and the first terminal of the second capacitor C2 respectively; the first terminal of the fifth transistor M5 is used to input the signal output by the first power supply PVDD; the second terminal of the fifth transistor M5 is electrically connected to the first terminal of the light-emitting element D1; the control terminal of the sixth transistor M6 is connected to the second scan signal SCAN2; the first terminal of the sixth transistor M6 is connected to the control terminal of the fifth transistor M5; the second terminal of the sixth transistor M6 is connected to the second terminal of the fifth transistor M5; the first terminal of the seventh transistor M7 is connected to the first terminal of the light-emitting element D1; the second terminal of the seventh transistor M7 is connected to the reset voltage VRST; the control terminal of the seventh transistor M7 is connected to the reset control signal VINI. In this embodiment, the pixel driving circuit forms a 7T2C current driving pixel circuit, which can weaken the influence of charge injection, reduce random offset, and the added negative feedback module 16 suppresses the change in light-emitting current caused by node voltage fluctuations, effectively improving the display uniformity of the pixel driving circuit.

[0050] Continue to refer to Figure 3 and 4Optionally, the pixel driving circuit may further include: a light emission control module 15 and a negative feedback module 16; the light emission control module 15 includes a third transistor M3; the third transistor M3 is used to connect the second terminal of the fifth transistor M5 and the first terminal of the light emission element D1; the negative feedback module 16 includes a fourth transistor M4; the fourth transistor M4 is connected to the first power supply PVDD and the first terminal of the fifth transistor M5; the control terminal of the fourth transistor M4 is connected to the first terminal of the fifth transistor M5; the control terminal of the third transistor M3 is connected to the light emission control signal; the control terminal of the seventh transistor M7 is connected to the reset control signal; the first scan signal SCAN1, the second scan signal SCAN2, the light emission control signal EMIT, and the reset control signal VINI are configured to achieve the following driving: during the initialization phase T1, the second transistor M2, the third transistor M3, the fourth transistor M4, the fifth transistor M5, the sixth transistor M6, and the seventh transistor M7 are turned on; the first transistor M1 is turned off. During the threshold compensation phase T2, transistors M2, M4, M5, and M6 are turned on; transistors M1, M7, and M3 are turned off. During the data writing phase T3, transistor M1 is turned on; transistors M2, M3, M4, M5, M6, and M7 are turned off. During the pre-stabilization phase T4, transistors M3, M4, M5, and M7 are turned on; transistors M1, M2, and M6 are turned off. During the light-emitting phase T5, transistors M3, M4, and M5 are turned on; transistors M1, M2, M6, and M7 are turned off. The on-current of transistor M3 during the initialization phase is less than the on-current of transistor M3 during the pre-stabilization and light-emitting phases.

[0051] The following is Figure 4 The specific embodiment shown provides a detailed description of the operation process of the pixel driving circuit. For example... Figure 3 and Figure 4 In this embodiment, the first scan signal SCAN1, the second scan signal SCAN2, the light emission control signal EMIT, and the reset control signal VINI are illustrated using a low level as the enable level and a high level as the disable level, as shown below:

[0052] During initialization phase T1, the second scan signal SCAN2 and the reset control signal VINI are at low levels, the first scan signal SCAN1 is at a high level, and the light emission control signal EMIT is at the BIAS potential. It's important to note that the BIAS potential enables the third transistor M3 to conduct, but its conduction current is relatively small, resulting in lower power consumption for the third transistor M3, which is beneficial for the low power consumption requirements of the display panel. In this embodiment, the third transistor M3 at this time can be referred to as the first conduction state. Optionally, the first conduction state controlled by the BIAS potential means that the third transistor M3 operates in the linear region; the third transistor M3 operates in the saturation region under the enable level control. During initialization phase T1, the second transistor M2, the third transistor M3, the fifth transistor M5, the fourth transistor M4, the sixth transistor M6, and the seventh transistor M7 are turned on. The reset current flows from one end of the first power supply PVDD to one end of the reset signal VRST. The voltage of the third node N3 is the reference voltage V. ofs The first node N1 and the second node N2 are at a lower potential, which is the potential of the reset voltage VRST.

[0053] During the threshold compensation phase T2, the second scan signal SCAN2 and the reset control signal VINI are at low level, while the first scan signal SCAN1 and the light emission control signal EMIT are at high level. At this time, the second transistor M2, the fourth transistor M4, the fifth transistor M5, and the sixth transistor M6 are turned on, and the potential Un3 of the third node N3 is the reference potential V. ofs The potential Un1 of the first node N1 and the potential Un2 of the second node N2 are Un1 = Un2 = V. NF1 -V thp , where V NF1 The voltage value of the fourth node NF is given. When the second scan signal SCAN2 changes from low to high, charge injection occurs into the first node N1, the second node N2, and the third node N3. Therefore, when the second scan signal SCAN2 ends at the low level, the potential of each node is given. Where C1 is the capacitance of the first capacitor; C2 is the capacitance of the second capacitor; ΔV1 is the difference between the high and low levels of the second scan signal SCAN2; and Cot is the total capacitance generated by the capacitor network seen between the first node N1 and the third node N3, excluding C1 and C2 (including at least the first parasitic capacitance Cgd1, the second parasitic capacitance Cgs2, and the third parasitic capacitance Cgd2). Therefore, although additional charge is injected into the first node N1, the simultaneous voltage changes at both the first node N1 and the third node N3 significantly weaken the effect of charge injection, making the threshold voltage captured by the pixel driving circuit closer to the actual value V.thp Furthermore, the threshold voltage captured by the pixel driving circuits at each position is consistent, thus perfectly realizing the threshold voltage compensation function; during the data input stage T3, the first scan signal SCAN1 is low, while the second scan signal SCAN2, the reset control signal VINI, and the light emission control signal EMIT are high. At this time, the voltage V of the data signal is... data It is written to the third node N3, therefore When the first scan signal SCAN1 changes from low to high, charge injection is performed on the first node N1. Therefore, when the first scan signal SCAN1 ends its low state, the potential of the first node N1 is as follows:

[0054]

[0055] Wherein, ΔV2 is the difference between the high level and the low level of the first scan signal SCAN1;

[0056] During the pre-stabilization phase T4, the reset control signal VINI and the light emission control signal EMIT are at low levels, while the first scan signal SCAN1 and the second scan signal SCAN2 are at high levels. At this time, the third transistor M3 is turned on, and the current value of the third transistor M3 is higher than its current value in the first on state, so that the fifth transistor M5 can quickly charge the first end of the light-emitting element and prevent the light-emitting element from color shifting due to insufficient charging. At this time, the on state of the third transistor M3 is the second on state. Optionally, the second on state is the working state of the third transistor M3 in the saturation region. At this time, the fourth transistor M4, the fifth transistor M5, the third transistor M3, and the seventh transistor M7 are turned on, and the light-emitting current flows from the first voltage PVDD terminal to the reset voltage VRST terminal. At this time, the first node N1 and the second node N2 stabilize at the voltage corresponding to the gray-scale current. During the light-emitting stage T5, the light-emitting control signal EMIT is low, and the first scan signal SCAN1, the second scan signal SCAN2, and the reset control signal VINI are high. At this time, the seventh transistor M7 is turned off, and the fourth transistor M4, the fifth transistor M5, and the third transistor M3 are turned on. The third transistor M3 continues to maintain the second on state. The gray-scale current flows from the first power supply PVDD terminal through the light-emitting element D1 to the second power supply PVEE terminal. The gray-scale current is:

[0057]

[0058] Where μ is the carrier mobility of the PMOS transistor; C OX Capacitance per unit area of ​​oxide layer; The width-to-length ratio of the PMOS transistor; |V thp | represents the threshold voltage of the PMOS transistor; V DSV is the source-drain voltage difference of the PMOS transistor; m is the mobility; V T It represents the absolute temperature coefficient.

[0059] As can be seen from formula (2), the pixel driving circuit weakens the effect of charge injection, thus reducing the difference in light emission current between the near-end pixel driving circuit and the far-end pixel driving circuit, so that the display panel has higher display uniformity and can weaken the effect of IR drop (power supply voltage drop) on display uniformity.

[0060] To further demonstrate the beneficial effects of the pixel driving circuit of the present invention, this embodiment provides a scheme that does not process charge injection, as a comparative example of the present invention. Figure 5 and Figure 6 As shown, Figure 5 This is a comparative structural diagram of a pixel driving circuit provided in an embodiment of the present invention. Figure 6 for Figure 5 Timing diagram of the mid-pixel driving circuit. Figure 5 This is a pixel driving circuit comprising transistors M1′, M2′, M3′, M4′, and MD′, and a first capacitor C1′ and a second capacitor C2′. The pixel driving circuit is controlled by scan signals SCAN1′ and SCAN2′ and an emission control signal EMIT′, and includes, for example... Figure 5 The nodes N1′, N2′, and N3′ shown are as follows: Figure 6 The initialization stage T1′, threshold compensation stage T2′, data writing stage T3′, and light emission stage T4′ are shown. Figure 5 The working process of the comparative model is as follows:

[0061] ELVDD is the positive voltage of the pixel driving circuit, and ELVEE is the negative voltage for the pixel driving circuit to operate. The scan signal SCAN1′ controls the writing of the data voltage DATA, the scan signal SCAN2′ controls the reset and threshold compensation of the light-emitting element, and the light-emitting control signal EMIT′ controls the light-emitting element to emit light. When EMIT′ is at BIAS′, the scan signals SCAN1′ and SCAN2′ are low, transistors M1′, M2′, and M3′ are simultaneously turned on, the reference voltage Vofs is written to node N3′, and the reset voltage VRST′ is written to the anode of the light-emitting element. Nodes N1′, N2′, and N3′ obtain their initial potentials. Simultaneously, the reset voltage VINI′ is written to the anode of the light-emitting element through transistor M3′. When the scan signals SCAN1′ and SCAN2′ are both high and the light-emitting control signal EMIT′ is low, the light-emitting element begins to emit light, and its current formula is:

[0062]

[0063] As can be seen from formula (3), the pixel circuit realizes the relationship between the light-emitting current and the threshold voltage V of the transistor MD. thp It is unrelated, and the luminous current is unrelated to the power supply voltage ELVDD. However, as the display resolution gradually increases, the pixel pitch becomes smaller and smaller, so the capacitance values ​​of the capacitors (C1, C2) also become smaller and smaller. When the scan signal flips from low to high, the effect of charge injection becomes more and more obvious, so the difference between far-end and near-end pixels becomes more significant, which leads to a deterioration in display uniformity.

[0064] When threshold compensation ends, the voltages at nodes N1′ and N2′ are Un1′=Un2′=ELVDD-V thp At this time, the scanning signal SCAN2′ changes from low level to high level, and the potential change is ΔV1. Due to the influence of charge injection, the final potentials of nodes N1′ and N2′ are: Un1′=ELVDD-V thp +ΔV1, from Figure 6 It can be seen that the threshold compensation stage occurs during the SCAN2′ transition of the scanning signal. However, due to the influence of charge injection, the final threshold value becomes inaccurate, and the amount of charge injected at different locations varies, resulting in different threshold voltages. Therefore, the threshold compensation function is inaccurate and uniformity deteriorates during this period. And when the data writing stage ends... At this moment, the scanning signal SCAN1′ changes from low level to high level, and the potential changes by ΔV2. Due to the influence of charge injection, the final potential of node N1′ is:

[0065]

[0066] Therefore, the final luminous current is:

[0067]

[0068] As can be seen from formula (5), the final luminous current is related to charge injection. However, the charge injection at the near end and the far end of the same row of pixels is different. That is, the near end charge injection is ΔV1_1 and the far end charge injection is ΔV1_2. Since ΔV1_2 < ΔV1_1, the luminous current at the near end and the far end are different. Furthermore, charge injection will increase the difference in random offset, which will ultimately exacerbate the non-uniformity of the display.

[0069] As can be seen from the comparison between formula (2) and formula (5), the pixel driving circuit in this embodiment weakens the influence of charge injection, thus reducing the difference in light emission current between the near-end circuit and the far-end circuit and improving the uniformity of the display panel.

[0070] Based on the same concept, embodiments of the present invention also provide a driving method for a pixel driving circuit. Applicable to the pixel driving circuit provided in any embodiment of the present invention, the pixel driving circuit further includes a light-emitting control module; the light-emitting control module is disposed between the second end of the driving module and the first end of the light-emitting element; Figure 7 This is a schematic flowchart of a pixel driving circuit driving method provided in an embodiment of the present invention, as shown below. Figure 7 As shown, the driving method of the pixel driving circuit in this embodiment includes the following steps:

[0071] Step S101: During the initialization phase, the reset module transmits the reset voltage to the first terminal of the light-emitting element; the light-emitting control module is in the first conducting state under the control of the light-emitting control signal, and is used to transmit the reset voltage to the second terminal of the driving module; the threshold compensation module transmits the reset voltage to the control terminal of the driving module; the data writing module transmits the reference voltage to the first terminal of the second capacitor under the control of the second scan signal.

[0072] Step S102: In the threshold compensation stage, the threshold compensation module compensates the threshold voltage of the drive module to the control terminal of the drive module; the data writing module continues to transmit the reference voltage to the first terminal of the second capacitor under the control of the second scan signal.

[0073] Step S103: During the data writing stage, the data writing module transmits the data signal to the first end of the second capacitor under the control of the first scan signal.

[0074] Step S104: In the pre-stabilization stage, the light-emitting control module is in the second conduction state under the control of the light-emitting control signal; the reset module is turned on under the control of the reset control signal; and there is a connection between the first power supply and the reset voltage.

[0075] Step S105: During the light-emitting stage, the light-emitting control module is in the second conduction state under the control of the light-emitting control signal, so that the driving module generates a driving current to be transmitted to the light-emitting element.

[0076] The conduction current of the light-emitting control module in the first conduction state is less than the conduction current of the light-emitting control module in the second conduction state.

[0077] In this embodiment of the invention, the driving module of the pixel driving circuit is connected to a first power supply to provide a light-emitting driving signal to the light-emitting element. The threshold compensation module is used to perform threshold compensation on the control terminal of the driving module. A first capacitor is connected between the control terminal and the first terminal of the driving module. The data input module is connected to the control terminal of the driving module through a second capacitor and outputs a data signal to the second capacitor under the control of the first scan signal. Under the control of the second scan signal, it outputs a reference voltage to the second capacitor. The threshold compensation module is connected to the control terminal and the second terminal of the driving module under the control of the second scan signal. In this embodiment, the second scan signal simultaneously controls the data input module and the threshold compensation module. Therefore, the control terminals of the data input module and the threshold compensation module experience simultaneous voltage jumps, and charge injection occurs simultaneously across the two ends of the second capacitor. This minimizes the impact of charge injection on the threshold compensation of the control terminal of the driving module, resulting in the threshold voltage captured by the control terminal of the driving module being closer to the threshold voltage of the driving module itself. Thus, the threshold voltage captured by the control terminal of both the near-end and far-end pixel driving circuits tends to be consistent, ensuring a small brightness difference between the light-emitting elements at the near and far ends of the display panel and a uniform display. Furthermore, the threshold voltage captured in this embodiment is closer to the actual threshold voltage of the driving module, thereby achieving a more complete threshold compensation function, improving the accuracy of brightness display, and enhancing the quality of screen display.

[0078] This invention also provides a display panel. Figure 8 This is a schematic diagram of the structure of a display panel provided in an embodiment of the present invention, such as... Figure 8 As shown, the display panel 1 provided in this embodiment of the invention includes the pixel driving circuit 200 described in any embodiment of the invention. The display panel can be a display panel for electronic devices such as smart wearable devices for virtual reality, augmented reality, and mixed reality, and this embodiment does not impose any special limitations on it.

[0079] In this embodiment, the display panel includes the technical features of the pixel driving circuit provided in any embodiment of the present invention, and has the beneficial effects of the corresponding technical features, which will not be elaborated here.

[0080] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A pixel driving circuit, characterized in that, include: The system includes a drive module, a threshold compensation module, a reset module, a data input module, a first capacitor, and a second capacitor. The first terminal of the driving module is used to input the signal output by the first power supply; the second terminal of the driving module is used to provide a light-emitting driving signal to the light-emitting element; the threshold compensation module is used to connect the control terminal of the driving module and the second terminal of the driving module under the control of the second scan signal; the first terminal of the first capacitor is connected to the first power supply; the second terminal of the first capacitor is connected to the control terminal of the driving module. The data input module is connected to the first terminal of the second capacitor; the second terminal of the second capacitor is connected to the control terminal of the drive module; the data input module is connected to the data signal and the reference voltage respectively, and is used to output the data signal to the first terminal of the second capacitor under the control of the first scan signal, or to output the reference voltage to the first terminal of the second capacitor under the control of the second scan signal. The reset module is connected to the first end of the light-emitting element and is used to output a reset voltage to the first end of the light-emitting element, the second end of the driving module, and the control end of the driving module; The pixel driving circuit further includes: a light-emitting control module; the light-emitting control module is disposed between the second end of the driving module and the first end of the light-emitting element; The pixel driving circuit is configured to implement the following driving: During the initialization phase, the reset module transmits the reset voltage to the first terminal of the light-emitting element; the light-emitting control module is in a first conducting state under the control of the light-emitting control signal, and is used to transmit the reset voltage to the second terminal of the driving module; the threshold compensation module transmits the reset voltage to the control terminal of the driving module; the data writing module transmits the reference voltage to the first terminal of the second capacitor under the control of the second scan signal. During the threshold compensation phase, the threshold compensation module compensates the threshold voltage of the driving module to the control terminal of the driving module; the data writing module continues to transmit the reference voltage to the first terminal of the second capacitor under the control of the second scan signal. During the data writing phase, the data writing module transmits the data signal to the first terminal of the second capacitor under the control of the first scan signal; During the pre-stabilization phase, the light emission control module is in the second conduction state under the control of the light emission control signal; the reset module is turned on under the control of the reset control signal; and there is a connection between the first power supply and the reset voltage. During the light-emitting stage, the light-emitting control module is in a second conduction state under the control of the light-emitting control signal, so that the driving module generates a driving current to be transmitted to the light-emitting element; The conduction current of the light-emitting control module in the first conduction state is less than the conduction current of the light-emitting control module in the second conduction state.

2. The pixel driving circuit according to claim 1, characterized in that, The data input module includes: a first input unit and a second input unit; The first input unit is used to connect the data signal and the first terminal of the second capacitor under the control of the first scan signal; The second input unit is used to connect the reference voltage and the first terminal of the second capacitor under the control of the second scan signal.

3. The pixel driving circuit according to claim 2, characterized in that, The first input unit includes a first transistor; the second input unit includes a second transistor; The first terminal of the first transistor is connected to the data signal; the second terminal of the first transistor is connected to the first terminal of the second capacitor; the control terminal of the first transistor is connected to the first scan signal. The first terminal of the second transistor is connected to a reference voltage; the second terminal of the second transistor is connected to the first terminal of the second capacitor; and the control terminal of the second transistor is connected to a second scan signal.

4. The pixel driving circuit according to claim 1, characterized in that, The light-emitting control module includes: a third transistor; The control terminal of the third transistor is connected to the light emission control signal; the first terminal of the third transistor is connected to the second terminal of the driving module; and the second terminal of the third transistor is connected to the first terminal of the light-emitting element.

5. The pixel driving circuit according to claim 1, characterized in that, Also includes: Negative feedback module; The first end of the negative feedback module is connected to the first power supply; the second end of the negative feedback module is connected to the first end of the drive module; and the control end of the negative feedback module is connected to the second end of the negative feedback module.

6. The pixel driving circuit according to claim 5, characterized in that, The negative feedback module includes: a fourth transistor; The first terminal of the fourth transistor is connected to the first power supply; the second terminal of the fourth transistor is connected to the first terminal of the driving module; and the control terminal of the fourth transistor is connected to the second terminal of the fourth transistor.

7. The pixel driving circuit according to claim 3, characterized in that, The driving module includes a fifth transistor; the threshold compensation module includes a sixth transistor; the reset module includes a seventh transistor; The control terminal of the fifth transistor is connected to the second terminal of the first capacitor and the first terminal of the second capacitor, respectively; the first terminal of the fifth transistor is used to input the signal output by the first power supply; the second terminal of the fifth transistor is electrically connected to the first terminal of the light-emitting element. The control terminal of the sixth transistor is connected to the second scan signal; the first terminal of the sixth transistor is connected to the control terminal of the fifth transistor; the second terminal of the sixth transistor is connected to the second terminal of the fifth transistor. The first terminal of the seventh transistor is connected to the first terminal of the light-emitting element; the second terminal of the seventh transistor is connected to the reset voltage; and the control terminal of the seventh transistor is connected to the reset control signal.

8. The pixel driving circuit according to claim 7, characterized in that, Also includes: The light-emitting control module and the negative feedback module are provided. The light-emitting control module includes a third transistor, which is used to connect the second terminal of the fifth transistor to the first terminal of the light-emitting element. The negative feedback module includes a fourth transistor, which is connected to a first power supply and the first terminal of the fifth transistor. The control terminal of the fourth transistor is connected to the first terminal of the fifth transistor. The control terminal of the third transistor is connected to the light emission control signal; the control terminal of the seventh transistor is connected to the reset control signal. The first scan signal, the second scan signal, the light emission control signal, and the reset control signal are configured to implement the following drive: During the initialization phase, the second, third, fourth, fifth, sixth, and seventh transistors are turned on; the first transistor is turned off. During the threshold compensation phase, the second transistor, the fourth transistor, the fifth transistor, and the sixth transistor; The first transistor and the seventh transistor are turned on, and the third transistor is turned off; During the data writing phase, the first transistor is turned on; the second, third, fourth, fifth, sixth, and seventh transistors are turned off. During the pre-stabilization phase, the third, fourth, fifth, and seventh transistors are turned on; the first, second, and sixth transistors are turned off. During the light-emitting phase, the third, fourth, and fifth transistors are turned on; the first, second, sixth, and seventh transistors are turned off. The on-current of the third transistor during the initialization phase is less than the on-current of the third transistor during the pre-stabilization phase and the light-emitting phase.

9. A driving method for a pixel driving circuit, characterized in that, The pixel driving circuit according to any one of claims 1-8 further includes a light-emitting control module; the light-emitting control module is disposed between the second end of the driving module and the first end of the light-emitting element. The driving method of the pixel driving circuit includes: During the initialization phase, the reset module transmits the reset voltage to the first terminal of the light-emitting element; the light-emitting control module is in a first conducting state under the control of the light-emitting control signal, and is used to transmit the reset voltage to the second terminal of the driving module; the threshold compensation module transmits the reset voltage to the control terminal of the driving module; the data writing module transmits the reference voltage to the first terminal of the second capacitor under the control of the second scan signal. During the threshold compensation phase, the threshold compensation module compensates the threshold voltage of the driving module to the control terminal of the driving module; the data writing module continues to transmit the reference voltage to the first terminal of the second capacitor under the control of the second scan signal. During the data writing phase, the data writing module transmits the data signal to the first terminal of the second capacitor under the control of the first scan signal; During the pre-stabilization phase, the light emission control module is in the second conduction state under the control of the light emission control signal; the reset module is turned on under the control of the reset control signal; and there is a connection between the first power supply and the reset voltage. During the light-emitting stage, the light-emitting control module is in a second conduction state under the control of the light-emitting control signal, so that the driving module generates a driving current to be transmitted to the light-emitting element; The conduction current of the light-emitting control module in the first conduction state is less than the conduction current of the light-emitting control module in the second conduction state.

10. The driving method for the pixel driving circuit according to claim 9, characterized in that, During the threshold compensation phase, the reset module continuously transmits the reset voltage to the first end of the light-emitting element.

11. A display panel, characterized in that, Includes the pixel driving circuit described in any one of claims 1-8.

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