Pixel driving circuit, driving method thereof, and display panel

Abstract

The present invention provides a pixel driving circuit, comprising: a data writing subcircuit, a threshold compensation subcircuit, a driving subcircuit, and a storage subcircuit. The data writing subcircuit is configured to transmit a data voltage signal to a first terminal of the driving subcircuit in response to a first scanning signal; the threshold compensation subcircuit is configured to compensate the threshold voltage of the driving subcircuit in response to the first scanning signal; the storage subcircuit is configured to store the data voltage signal; the driving subcircuit is configured to provide a driving current to a light-emitting device to be driven based on the voltages at its first terminal and a first control terminal; and the pixel driving circuit further comprises a threshold voltage drift elimination subcircuit configured to transmit a variable reverse bias voltage signal to the second control terminal of the driving subcircuit in response to a second scanning signal; the variable reverse bias voltage signal has a polarity opposite to that of the data voltage signal. This pixel driving circuit can improve or eliminate threshold voltage drift in the driving subcircuit.

Description

Technical Field

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

[0002] At present, Micro Light Emitting Diode (Micro LED) display technology is developing rapidly. Due to its outstanding advantages such as small size, low power consumption, high color saturation, fast response speed and long life, it has attracted the investment of a large number of scientific and technological workers. Summary of the Invention

[0003] The present invention aims to address at least one of the technical problems existing in the prior art by providing a pixel drive circuit, a driving method thereof, and a display panel. This pixel drive circuit can improve or eliminate varying degrees of threshold voltage drift in the driver subcircuit as a function of data voltage signals, ensuring stable driving, improving or eliminating the light lag problem of light-emitting devices, and improving or preventing image retention on the display.

[0004] This embodiment provides a pixel driving circuit, comprising: a data writing subcircuit, a threshold compensation subcircuit, a driving subcircuit and a storage subcircuit; wherein,

[0005] The data writing sub-circuit is configured to transmit the data voltage signal to the first terminal of the driving sub-circuit in response to the first scanning signal;

[0006] The threshold compensation sub-circuit is configured to compensate the threshold voltage of the driving sub-circuit in response to the first scanning signal;

[0007] The storage sub-circuit is configured to store the data voltage signal;

[0008] The driving sub-circuit is configured to provide a driving current to the light-emitting device to be driven according to the voltages at the first terminal and the first control terminal;

[0009] Also included is a threshold voltage drift elimination sub-circuit configured to transmit a variable reverse bias voltage signal to the second control terminal of the driving sub-circuit in response to a second scanning signal;

[0010] The variable reverse bias voltage signal has a polarity opposite to that of the data voltage signal and is used to eliminate the threshold voltage drift of the driving sub-circuit caused by the data voltage signal in the previous frame or the previous row.

[0011] Optionally, the threshold voltage drift elimination sub-circuit includes an eighth transistor, the control electrode of the eighth transistor is connected to the second scan line, the first electrode of the eighth transistor is connected to the second control end of the driving sub-circuit, and the second electrode of the eighth transistor is connected to the data line.

[0012] Optionally, the driving sub-circuit includes a driving transistor,

[0013] The first electrode of the driving transistor is used as the first terminal of the driving sub-circuit, the second electrode of the driving transistor is used as the second terminal of the driving sub-circuit, the first control electrode of the driving transistor is used as the first control terminal of the driving sub-circuit, and the second control electrode of the driving transistor is used as the second control terminal of the driving sub-circuit;

[0014] A PNP transistor is formed between the first control electrode of the driving transistor and the first electrode and the second electrode, and an NPN transistor is formed between the second control electrode of the driving transistor and the first electrode and the second electrode;

[0015] Alternatively, an NPN transistor is formed between the first control electrode of the driving transistor and the first electrode and the second electrode, and a PNP transistor is formed between the second control electrode of the driving transistor and the first electrode and the second electrode.

[0016] Optionally, the threshold compensation sub-circuit includes a threshold compensation transistor, the data writing sub-circuit includes a data writing transistor, and the storage sub-circuit includes a storage capacitor;

[0017] The first electrode of the driving transistor is connected to the second electrode of the data writing transistor, the second electrode of the driving transistor is connected to the first electrode of the threshold compensation transistor, the first control electrode of the driving transistor is connected to the second electrode of the threshold compensation transistor and the first plate of the storage capacitor, and the second control electrode of the driving transistor is connected to the first electrode of the eighth transistor;

[0018] A first electrode of the data writing transistor is connected to the data line, and a control electrode of the data writing transistor is connected to the first scan line;

[0019] The control electrode of the threshold compensation transistor is connected to the first scan line;

[0020] The second plate of the storage capacitor is connected to the first power supply voltage line.

[0021] Optionally, it also includes:

[0022] The first light-emitting control sub-circuit is configured to control whether a first voltage can be written into the first terminal of the driving sub-circuit in response to a first light-emitting control signal.

[0023] Optionally, the first light emission control subcircuit includes a first light emission control transistor;

[0024] A first electrode of the first light-emitting control transistor is connected to a first power supply voltage line, a second electrode of the first light-emitting control transistor is connected to a first end of the driving sub-circuit, and a control electrode of the first light-emitting control transistor is connected to a first light-emitting control line.

[0025] Optionally, it also includes:

[0026] The first reset sub-circuit is configured to respond to the third scan signal and reset the voltage of the first control terminal of the driving sub-circuit through the first initialization signal.

[0027] Optionally, the first reset subcircuit includes a first reset transistor;

[0028] A first electrode of the first reset transistor is connected to a first initialization signal terminal, a second electrode of the first reset transistor is connected to a first control terminal of the driving sub-circuit, and a control electrode of the first reset transistor is connected to the third scan line.

[0029] Optionally, it also includes:

[0030] The second light-emitting control sub-circuit is configured to switch on or off the connection between the driving sub-circuit and the light-emitting device to be driven in response to a second light-emitting control signal.

[0031] Optionally, the second light emitting control subcircuit includes a second light emitting control transistor;

[0032] The first electrode of the second light emitting control transistor is connected to the second end of the driving sub-circuit, the second electrode of the second light emitting control transistor is connected to the first electrode of the light emitting device to be driven, and the control electrode of the second light emitting control transistor is connected to the second light emitting control line.

[0033] Optionally, it also includes:

[0034] The second reset sub-circuit is configured to initialize the light-emitting device to be driven through a second initialization signal in response to the third scan signal.

[0035] Optionally, the second reset subcircuit includes a second reset transistor;

[0036] A first electrode of the second reset transistor is connected to the first electrode of the light-emitting device to be driven, a second electrode of the second reset transistor is connected to a second initialization signal terminal, and a control electrode of the second reset transistor is connected to a third scan line.

[0037] An embodiment of the present invention further provides a display panel, comprising a plurality of pixel units, each of the plurality of pixel units comprising a pixel driving circuit and a light emitting device;

[0038] The pixel driving circuit includes the above-mentioned pixel driving circuit.

[0039] An embodiment of the present invention further provides a driving method for the above pixel driving circuit, comprising:

[0040] In the threshold voltage drift elimination stage, the threshold voltage drift elimination sub-circuit writes the variable reverse bias voltage signal input on the data line to the second control terminal of the driving sub-circuit in response to the second scanning signal, so as to eliminate the threshold voltage drift of the driving sub-circuit caused by the data voltage signal of the previous frame or the previous row input on the data line;

[0041] In the reset phase, the first reset subcircuit, in response to the third scan signal, resets the voltage of the first control terminal of the driving subcircuit through the first initialization signal. At the same time, the second reset subcircuit, in response to the third scan signal, initializes the light-emitting device to be driven through the second initialization signal.

[0042] In the data writing and threshold compensation stage, the data writing sub-circuit writes the data voltage signal to the first end of the driving sub-circuit in response to the first scanning signal, and at the same time, the threshold compensation sub-circuit compensates the threshold voltage of the driving sub-circuit in response to the first scanning signal;

[0043] During the light-emitting stage, the first light-emitting control subcircuit responds to the first light-emitting control signal to control the first voltage to be written into the first end of the driving subcircuit. At the same time, the second light-emitting control subcircuit responds to the second light-emitting control signal to turn on the connection between the driving subcircuit and the light-emitting device to be driven.

[0044] Optionally, the second scanning signal, the third scanning signal and the first scanning signal are input sequentially line by line within one frame display time;

[0045] The second scanning signal is input during the threshold voltage drift elimination phase;

[0046] The third scanning signal is input during the reset phase;

[0047] The first scanning signal is input during the data writing and threshold compensation phase.

[0048] Optionally, the first light-emitting control signal is input during the threshold voltage drift elimination phase and the light-emitting phase;

[0049] The second light emitting control signal is input during a reset phase and a light emitting phase.

[0050] Optionally, the electric field strength formed by the first initialization signal is smaller than the electric field strength formed by the variable reverse bias voltage signal.

[0051] The electric field strength formed by the second initialization signal is smaller than the electric field strength formed by the variable reverse bias voltage signal.

[0052] Beneficial effects of the present invention: The pixel driving circuit provided by the present invention, by setting a threshold voltage drift elimination sub-circuit, the variable reverse bias voltage signal can improve or eliminate the threshold voltage drift of the driving sub-circuit caused by the data voltage signal when the size changes, and limit the threshold voltage drift range of the driving sub-circuit, stabilize the driving of the driving sub-circuit, and improve or eliminate the light-emitting hysteresis problem of the light-emitting device. At the same time, the reverse bias voltage signal is variable in size according to the different degrees of threshold voltage drift of the driving sub-circuit caused by data voltage signals of different sizes, thereby more accurately improving or eliminating the different degrees of threshold voltage drift of the driving sub-circuit with the change of the data voltage signal, so that the threshold voltage drift of the driving sub-circuit is always maintained in a dynamic balance process, thereby ensuring the stable driving of the pixel driving circuit, improving or eliminating the light-emitting hysteresis problem of the light-emitting device, and improving or avoiding the appearance of afterimages on the display screen.

[0053] The display panel provided by the present invention improves the display stability and display effect of the display panel by adopting the above-mentioned pixel driving circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 Schematic diagram of an exemplary display substrate structure.

[0055] Figure 2 FIG. 1 is a schematic diagram of an exemplary pixel driving circuit.

[0056] Figure 3 for Figure 2 The working timing diagram of the pixel driving circuit is shown.

[0057] Figure 4a Schematic diagram of the principle of driving transistor threshold voltage drift.

[0058] Figure 4b The figure is a graph showing the conduction performance of the driving transistor under different display grayscales.

[0059] Figure 5 This is a schematic diagram showing an afterimage appearing on a test screen after the pixel driving circuit stops driving.

[0060] Figure 6a FIG. 4 is a schematic diagram of a pixel driving circuit according to the embodiment of the present invention.

[0061] Figure 6bSchematic diagram of the principle of eliminating the threshold voltage drift of the driving transistor by the threshold voltage drift elimination sub-circuit in this embodiment.

[0062] Figure 6c Schematic diagram of modulation of the conduction performance curve of the driving transistor by the threshold voltage drift elimination sub-circuit in this embodiment.

[0063] Figure 7 for Figure 6a The working timing diagram of the pixel driving circuit is shown.

[0064] Figure 8 FIG. 4 is an equivalent circuit diagram of the pixel driving circuit in the threshold voltage drift elimination stage in this embodiment.

[0065] Figure 9 FIG. 4 is an equivalent circuit diagram of the pixel driving circuit in the reset stage in this embodiment. DETAILED DESCRIPTION

[0066] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0067] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0068] Figure 1 is a schematic diagram of an exemplary display substrate structure; Figure 2 is a schematic diagram of an exemplary pixel driving circuit; Figure 1 and 2As shown, the display substrate includes a plurality of pixel units arranged in an array, and each pixel unit 100 includes a pixel driving circuit and a light-emitting device D. The pixel driving circuit in each pixel unit 100 may include: a first reset subcircuit 1, a threshold compensation subcircuit 2, a driving subcircuit 3, a data writing subcircuit 4, a first light-emitting control subcircuit 5, a second light-emitting control subcircuit 6, a second reset subcircuit 7, and a storage subcircuit 8.

[0069] The first reset subcircuit 1 is connected to the control terminal of the driver subcircuit 3 and is configured to reset the control terminal of the driver subcircuit 3 under the control of a first reset signal. The threshold compensation subcircuit 2 is electrically connected to the control terminal and the second terminal of the driver subcircuit 3, respectively, and is configured to perform threshold compensation for the driver subcircuit 3. The data write subcircuit 4 is electrically connected to the first terminal of the driver subcircuit 3 and is configured to write a data signal into the storage subcircuit under the control of a scan signal. The storage subcircuit 8 is electrically connected to the control terminal of the driver subcircuit 3 and the first power supply voltage line Vdd, respectively, and is configured to store the data signal. The first light emission control subcircuit 5 is electrically connected to the first power supply voltage line Vdd and the first terminal of the driver subcircuit 3, respectively, and is configured to connect or disconnect the driver subcircuit 3 and the first power supply voltage line Vdd. The second light emission control subcircuit 6 is electrically connected to the second terminal of the driver subcircuit 3 and the first electrode of the light emitting device D, respectively, and is configured to connect or disconnect the driver subcircuit 3 and the light emitting device D. The second reset sub-circuit 7 is electrically connected to the first electrode of the light emitting device D, and is configured to reset the control terminal of the driving sub-circuit 3 and the first electrode of the light emitting device D under the control of a second reset control signal.

[0070] Continue to refer to Figure 2 The first reset subcircuit includes a first reset transistor T1, the threshold compensation subcircuit 2 includes a threshold compensation transistor T2, the driving subcircuit 3 includes a driving transistor T3, the control terminal of the driving subcircuit 3 includes the control electrode of the driving transistor T3, the first terminal of the driving subcircuit 3 includes the first electrode of the driving transistor T3, and the second terminal of the driving subcircuit 3 includes the second electrode of the driving transistor T3. The data write subcircuit 4 includes a data write transistor T4, the storage subcircuit 7 includes a storage capacitor Cst, the first light emission control subcircuit 5 includes a first light emission control transistor T5, the second light emission control subcircuit 6 includes a second light emission control transistor T6, and the second reset subcircuit 7 includes a second reset transistor T7.

[0071] In this embodiment, the driving transistor T3, the data writing transistor T4, the threshold compensation transistor T2, the first light-emitting control transistor T5, the second light-emitting control transistor T6, the first reset transistor T1, and the second reset transistor T7 are all P-type transistors. Each transistor includes a first electrode, a second electrode, and a control electrode; wherein the control electrode serves as the gate of the transistor, one of the first electrode and the second electrode serves as the source of the transistor, and the other serves as the drain of the transistor; and the source and drain of the transistor can be symmetrical in structure, so the source and drain can be physically indistinguishable. In this embodiment, in order to distinguish the transistors, except for the gate serving as the control electrode, the first electrode is directly described as the source and the second electrode as the drain. Therefore, the source and drain of all or part of the transistors in the embodiments of the present disclosure can be interchangeable as needed.

[0072] Continue to refer to Figure 2The drain of the data writing transistor T4 is electrically connected to the source of the driving transistor T3, the source of the data writing transistor T4 is configured to be electrically connected to the data line Data to receive the data signal, and the gate of the data writing transistor T4 is configured to be electrically connected to the first scan line Gate(n) to receive the scan signal; the second plate of the storage capacitor Cst is electrically connected to the first power supply voltage line Vdd, and the first plate of the storage capacitor Cst is electrically connected to the gate of the driving transistor T3; the source of the threshold compensation transistor T2 is electrically connected to the gate of the driving transistor T3, the drain of the threshold compensation transistor T2 is electrically connected to the drain of the driving transistor T3, and the gate of the threshold compensation transistor T2 is configured to be electrically connected to the first scan line Gate(n) to receive the compensation control signal; the source of the first reset transistor T1 is configured to be electrically connected to the first initialization signal terminal Vinit1 to receive the first reset signal, the drain of the first reset transistor T1 is electrically connected to the gate of the driving transistor T3, and the gate of the first reset transistor T1 is configured to be electrically connected to the third scan line Gate(n-1) The first light emitting device D is electrically connected to the first power supply voltage line Vdd, the drain of the first light emitting control transistor T5 is electrically connected to the source of the driving transistor T3, and the gate of the first light emitting control transistor T5 is configured to be electrically connected to the light emitting control line EM(n) to receive the light emitting control signal; the source of the second light emitting control transistor T6 is electrically connected to the drain of the driving transistor T3, the drain of the second light emitting control transistor T6 is electrically connected to the first electrode of the light emitting device D, and the gate of the second light emitting control transistor T6 is configured to be electrically connected to the light emitting control line EM(n) to receive the light emitting control signal; the second electrode of the light emitting device D is electrically connected to the second power supply terminal VSS.

[0073] Figure 3 for Figure 2 The working timing diagram of the pixel driving circuit shown in FIG. Figure 2 and 3 As shown, the driving method of the above pixel driving circuit may include the following stages:

[0074] Reset phase (t1): A low-level signal is written to the third scan line Gate(n-1), while high-level signals are written to the first scan line Gate(n) and the light-emitting control line EM(n). The first reset transistor T1 and the second reset transistor T7 are turned on, and the gate of the driving transistor T3 is programmed with the first initialization voltage written by the first initialization signal terminal Vinit1, preparing for the writing of the data voltage Vdata for the next frame. The anode of the light-emitting device D is then programmed with a second reset signal (the voltage at the second initialization signal terminal Vinit2 ≤ VSS) via the second reset transistor T7, disabling the forward conduction state of the light-emitting device D. This gradually dissipates the internal electric field formed by the directional movement of impurity ions within the light-emitting device D, thereby restoring the characteristics of the light-emitting device D.

[0075] Data writing and threshold compensation phase (t2): A low-level signal is written to the first scan line Gate(n), and a high-level signal is written to the third scan line Gate(n-1) and the light-emitting control line EM(n); the data writing transistor T4 and the threshold compensation transistor T2 are turned on. The driving transistor T3 is connected to form a diode structure by the threshold compensation transistor T2. The data voltage Vdata written on the data line Data is written to the gate of the driving transistor T3 through the data writing transistor T4 and the threshold compensation transistor T2 until the driving transistor T3 is turned off. The gate voltage of the driving transistor T3 is Vdata+Vth (Vth<0, Vth is the threshold voltage of the driving transistor T3) and is stored in the storage capacitor Cst. The voltages of the first plate and the second plate of the storage capacitor Cst are Vdata+Vth and Vdd, respectively.

[0076] Light-emitting phase (t3): A low-level signal is written to the light-emitting control line EM(n), and high-level signals are written to the first scan line Gate(n) and the third scan line Gate(n-1). The first light-emitting control transistor T5 and the second light-emitting control transistor T6 are both turned on. The source of the driving transistor T3 is connected to the first power supply voltage line Vdd, and the source voltage of the driving transistor T3 changes instantaneously from Vdata in the previous phase to Vdd. The light-emitting device D emits light under the drive transistor T3. At this time, the driving transistor T3 operates in the saturation region. The gate voltage of the driving transistor T3 is Vdata + Vth, and the source voltage of the driving transistor T3 is Vdd. Therefore, the gate-source voltage of the driving transistor T3 is: Vgs = (Vdata + Vth) - Vdd, until the reset phase of the next frame.

[0077] The light-emitting current of the light-emitting device D is equal to the current flowing through the driving transistor T3, and its expression is as follows:

[0078] I D =β(Vgs-Vth) 2

[0079] =β(Vdata+Vth-dd-Vth) 2

[0080] =β(Vdata-Vdd) 2 ;

[0081] in, μ n is the electron mobility of the driving transistor T3, C ox is the insulation capacitance per unit area, is the width-to-length ratio of the driving transistor T3.

[0082] The inventors discovered that Figure 4a 、 Figure 4b and Figure 5 As shown in FIG, the driving transistor in the pixel driving circuit has instability, that is, the threshold voltage will drift under long-term gate bias. Figure 4a , is a schematic diagram of the principle of threshold voltage drift of the driving transistor. The main reason for the threshold voltage drift of the driving transistor is the charge injection between the active layer ACT and the gate insulating layer GI. The injected charge can directly tunnel from the cross section of the semiconductor active layer ACT to the trap of the gate insulating layer GI and gradually fill up the interface, or the charge tunnels into the conduction band of the gate insulating layer GI and is then deeply trapped at the interface not far from the semiconductor active layer ACT. The threshold voltage of the driving transistor will drift when the DC gate bias is applied for a long time, such as Figure 4b , is the conduction performance curve of the driving transistor under different display grayscales, from Figure 4b It can be seen that the threshold voltage drift degree of the driving transistor is different under different display grayscales of the light-emitting device. For example, when the light-emitting device displays a grayscale of 255, the threshold voltage of the driving transistor is Vth2, and when the light-emitting device displays a grayscale of 0, the threshold voltage of the driving transistor is Vth2'. The standard value of the threshold voltage of the driving transistor under normal circumstances is Vth1. It can be seen that the threshold voltage of the driving transistor under different display grayscales has deviations relative to the standard value under normal circumstances (i.e., the threshold voltage drifts). When the display grayscale of the previous frame (or previous row) picture is different from that of the current frame (or current row) picture, for example, the previous frame picture displays a grayscale of 255 and the current frame picture displays a grayscale of 63, the threshold voltage drift degree of the driving transistor will change, which will cause the light-emitting device driven by the driving transistor to emit light to have a light lag problem, thereby causing a display screen afterimage problem when the display panel finishes displaying the current frame picture. Figure 5 shown.

[0083] from Figure 5 As can be seen in the figure, after the test image is displayed for 10 seconds, the pixel driving circuit stops driving, and the 63-grayscale image will remain. After remaining for a few seconds, it disappears and is no longer displayed.

[0084] In response to the above technical problems, the following technical solutions are provided in the embodiments of the present disclosure.

[0085] Figure 6a is a schematic diagram of a pixel driving circuit of this embodiment; Figure 6a As shown, an embodiment of the present disclosure provides a pixel driving circuit, which may include the above-mentioned data writing sub-circuit 4, threshold compensation sub-circuit 2, driving sub-circuit 3, and storage sub-circuit 8. In particular, the pixel driving circuit also includes a threshold voltage drift elimination sub-circuit 9, wherein the data writing sub-circuit 4 is configured to transmit a data voltage signal to the first end of the driving sub-circuit 3 in response to a first scanning signal; the threshold compensation sub-circuit 2 is configured to compensate for the threshold voltage of the driving sub-circuit 3 in response to the first scanning signal; the storage sub-circuit 8 is configured to store the data voltage signal; the driving sub-circuit 3 is configured to provide a driving current for the light-emitting device D to be driven according to the voltages of its first end and the first control end; the threshold voltage drift elimination sub-circuit 9 is configured to transmit a variable reverse bias voltage signal to the second control end of the driving sub-circuit 3 in response to a second scanning signal; the variable reverse bias voltage signal has a polarity opposite to that of the data voltage signal and is used to eliminate the threshold voltage drift of the driving sub-circuit 3 caused by the data voltage signal of the previous frame or the previous row.

[0086] Among them, Figure 6b and Figure 6c As shown, Figure 6b FIG. 1 is a schematic diagram showing the principle of eliminating the threshold voltage drift of the driving transistor by the threshold voltage drift elimination sub-circuit in this embodiment, wherein SD represents the source and drain of the driving transistor, Figure 6c This is a schematic diagram of the modulation of the conduction performance curve of the driving transistor by the threshold voltage drift elimination sub-circuit in this embodiment. The variable reverse bias voltage signal can improve or eliminate the threshold voltage drift of the driving sub-circuit 3 caused by the data voltage signal when the data voltage signal changes, and limit the threshold voltage drift range of the driving sub-circuit 3, stabilize the driving of the driving sub-circuit 3, and improve or eliminate the light-emitting hysteresis problem of the light-emitting device D. At the same time, the reverse bias voltage signal is variable in size according to the different degrees of threshold voltage drift of the driving sub-circuit 3 caused by data voltage signals of different sizes, thereby more accurately improving or eliminating the different degrees of threshold voltage drift of the driving sub-circuit 3 with the change of the data voltage signal, so that the threshold voltage drift of the driving sub-circuit 3 is always maintained in a dynamic balance process, thereby ensuring the stable driving of the pixel driving circuit, improving or eliminating the light-emitting hysteresis problem of the light-emitting device D, and improving or avoiding the appearance of afterimages on the display screen.

[0087] Optionally, refer to Figure 6aThe threshold voltage drift elimination sub-circuit 9 includes an eighth transistor T8, the control electrode of the eighth transistor T8 is connected to the second scan line Gate(n-2), the first electrode of the eighth transistor T8 is connected to the second control end of the driving sub-circuit 3, and the second electrode of the eighth transistor T8 is connected to the data line Data.

[0088] Alternatively, as Figure 6a As shown, the driving sub-circuit 3 includes a driving transistor T3. The first electrode of the driving transistor T3 serves as the first terminal of the driving sub-circuit 3, the second electrode of the driving transistor T3 serves as the second terminal of the driving sub-circuit 3, the first control electrode of the driving transistor T3 serves as the first control terminal of the driving sub-circuit 3, and the second control electrode of the driving transistor T3 serves as the second control terminal of the driving sub-circuit 3. A PNP transistor is formed between the first control electrode of the driving transistor T3 and the first and second electrodes, and an NPN transistor is formed between the second control electrode of the driving transistor T3 and the first and second electrodes. That is, the driving transistor T3 is a dual-gate transistor.

[0089] Optionally, an NPN transistor may be formed between the first control electrode of the driving transistor and the first electrode and the second electrode, and a PNP transistor may be formed between the second control electrode of the driving transistor and the first electrode and the second electrode.

[0090] Optionally, refer to Figure 6a The threshold compensation sub-circuit 2 includes a threshold compensation transistor T2, the data writing sub-circuit 4 includes a data writing transistor T4, and the storage sub-circuit 7 includes a storage capacitor Cst; the first electrode of the driving transistor T3 is connected to the second electrode of the data writing transistor T4, the second electrode of the driving transistor T3 is connected to the first electrode of the threshold compensation transistor T2, the first control electrode of the driving transistor T3 is connected to the second electrode of the threshold compensation transistor T2 and the first electrode plate of the storage capacitor Cst, and the second control electrode of the driving transistor T3 is connected to the first electrode of the eighth transistor T8; the first electrode of the data writing transistor T4 is connected to the data line Data, and the control electrode of the data writing transistor T4 is connected to the first scan line Gate(n); the control electrode of the threshold compensation transistor T2 is connected to the first scan line Gate(n); and the second electrode plate of the storage capacitor Cst is connected to the first power supply voltage line Vdd.

[0091] Optionally, refer to Figure 6a The pixel driving circuit further includes a first light emitting control sub-circuit 5 configured to control whether the first voltage can be written into the first end of the driving sub-circuit 3 in response to the first light emitting control signal.

[0092] Optionally, refer to Figure 6aThe first light-emitting control sub-circuit 5 includes a first light-emitting control transistor T5; a first electrode of the first light-emitting control transistor T5 is connected to the first power supply voltage line Vdd, a second electrode of the first light-emitting control transistor T5 is connected to the first end of the driving sub-circuit 3, and a control electrode of the first light-emitting control transistor T5 is connected to the first light-emitting control line EM2(n+1).

[0093] Optionally, refer to Figure 6a The pixel driving circuit further includes: a first reset sub-circuit 1, configured to respond to the third scanning signal and reset the voltage of the first control terminal of the driving sub-circuit 3 through the first initialization signal.

[0094] Optionally, refer to Figure 6a The first reset sub-circuit 1 includes a first reset transistor T1; a first electrode of the first reset transistor T1 is connected to the first initialization signal terminal Vint1, a second electrode of the first reset transistor T1 is connected to the first control terminal of the driving sub-circuit 3, and a control electrode of the first reset transistor T1 is connected to the third scan line Gate(n-1).

[0095] Optionally, refer to Figure 6a The pixel driving circuit further includes: a second light emitting control sub-circuit 6, configured to turn on or off the connection between the driving sub-circuit 3 and the light emitting device D to be driven in response to a second light emitting control signal.

[0096] Optionally, refer to Figure 6a The second light-emitting control sub-circuit 6 includes a second light-emitting control transistor T6; a first electrode of the second light-emitting control transistor T6 is connected to the second end of the driving sub-circuit 3, a second electrode of the second light-emitting control transistor T6 is connected to the first electrode of the light-emitting device D to be driven, and a control electrode of the second light-emitting control transistor T6 is connected to the second light-emitting control line EM1(n).

[0097] Optionally, refer to Figure 6a The pixel driving circuit further includes: a second reset sub-circuit 7 configured to initialize the light-emitting device D to be driven through a second initialization signal in response to the third scanning signal.

[0098] Optionally, refer to Figure 6a The second reset sub-circuit 7 includes a second reset transistor T7; a first electrode of the second reset transistor T7 is connected to the first electrode of the light-emitting device D to be driven, a second electrode of the second reset transistor T7 is connected to the second initialization signal terminal Vint2, and a control electrode of the second reset transistor T7 is connected to the third scan line Gate(n-1). The second electrode of the light-emitting device D is connected to the second power supply terminal VSS, which can be a voltage source to output a constant second voltage.

[0099] Optionally, one of the first power supply voltage line Vdd and the second power supply terminal VSS is a high voltage terminal, and the other is a low voltage terminal. The first power supply voltage line Vdd is a voltage source that outputs a constant first voltage, which is a positive voltage; and the second power supply terminal VSS can be a voltage source that outputs a constant second voltage, which is a negative voltage, etc. For example, in some examples, the second power supply terminal VSS can be grounded.

[0100] Optionally, according to the characteristics of the transistor, the transistor can be divided into an N-type transistor and a P-type transistor. For the sake of clarity, this embodiment uses a P-type transistor (e.g., a P-type MOS transistor) as an example to describe the technical solution of the present disclosure in detail. That is, in this embodiment, the eighth transistor T8, the data writing transistor T4, the threshold compensation transistor T2, the first light-emitting control transistor T5, the second light-emitting control transistor T6, the first reset transistor T1, and the second reset transistor T7 can all be P-type transistors. However, the transistors of this embodiment are not limited to P-type transistors. Those skilled in the art can also use N-type transistors (e.g., N-type MOS transistors) to implement the functions of one or more transistors in this embodiment according to actual needs.

[0101] In addition, the transistors used in this embodiment may be thin film transistors, field effect transistors, or other switching devices with the same characteristics. The thin film transistors may include oxide semiconductor thin film transistors, amorphous silicon thin film transistors, or polycrystalline silicon thin film transistors. Each transistor includes a first electrode, a second electrode, and a control electrode; wherein the control electrode serves as the gate of the transistor, one of the first electrode and the second electrode serves as the source of the transistor, and the other serves as the drain of the transistor; and the source and drain of the transistor may be symmetrical in structure, so the source and drain may be physically identical.

[0102] Optionally, the first initialization signal terminal Vinit1 and the second initialization signal terminal Vinit2 can be DC reference voltage terminals to output a constant DC reference voltage. The first initialization signal terminal Vinit1 and the second initialization signal terminal Vinit2 can be the same, for example, the first electrode of the first reset transistor T1 and the second electrode of the second reset transistor T7 are connected to the same initialization signal terminal. The first initialization signal terminal Vinit1 and the second initialization signal terminal Vinit2 can be high-voltage terminals or low-voltage terminals, as long as they can provide the first initialization signal and the second initialization signal to reset the first control electrode of the driving transistor T3 and the first electrode of the light-emitting element D. This disclosure is not limited to this.

[0103] in addition, Figure 6aThe threshold voltage drift elimination subcircuit, driving subcircuit, data writing subcircuit, storage subcircuit, threshold compensation subcircuit, first reset subcircuit, second reset subcircuit, first light-emitting control subcircuit and second light-emitting control subcircuit in the pixel driving circuit shown are only illustrative. The specific structure of each of the above subcircuits can be set according to actual application requirements, and this embodiment does not make specific limitations on this.

[0104] Optionally, the light-emitting device D may be a micro inorganic light-emitting diode, or further, a current-type light-emitting diode, such as a micro light-emitting diode (Micro LED) or a mini light-emitting diode (Mini LED). Of course, the light-emitting device D in this embodiment may also be an organic light-emitting diode (OLED). One of the first electrode and the second electrode of the light-emitting device D is an anode, and the other is a cathode; in this embodiment, the first electrode of the light-emitting device D is an anode, and the second electrode is a cathode.

[0105] Based on the above pixel driving circuit, this embodiment also provides a driving method of the pixel driving circuit, such as Figure 7 ,for Figure 6a The working timing diagram of the pixel driving circuit shown in FIG. 1 is shown; wherein the driving method of the pixel driving circuit includes the following stages:

[0106] In the threshold voltage drift elimination stage (t1), the threshold voltage drift elimination sub-circuit responds to the second scanning signal and writes the variable reverse bias voltage signal input on the data line to the second control terminal of the driving sub-circuit to eliminate the threshold voltage drift of the driving sub-circuit caused by the data voltage signal of the previous frame or the previous row input on the data line.

[0107] like Figure 8As shown in FIG. 1 , an equivalent circuit diagram of the pixel driving circuit in the threshold voltage drift elimination stage of the present embodiment; in the threshold voltage drift elimination stage, the first light-emitting control signal provided by the first light-emitting control line EM2(n+1) turns on the first light-emitting control transistor T5, and the voltage of the first electrode of the driving transistor T3 is reset to the first voltage provided by the first power supply voltage line Vdd; the second scanning signal provided by the second scanning line Gate(n-2) turns on the eighth transistor T8, and the variable reverse bias voltage signal is input to the second control electrode of the driving transistor T3 from the data line Data; the voltage Vb of the second control electrode of the driving transistor T3 is the variable reverse bias voltage, the voltage of the first electrode of the driving transistor T3 is the first voltage, and the voltage between the second control electrode and the first electrode of the driving transistor T3 is Vd. Difference Vbs=Vb-Vdd; Vbs is a positive voltage; the voltage of the first control electrode of the driving transistor T3 is the data voltage signal Vdata of the previous frame or the previous row, and the voltage difference Vgs between the first control electrode and the first electrode of the driving transistor T3 is Vdata-Vdd; then the voltage difference Vbg between the second control electrode and the first control electrode of the driving transistor T3 is Vb-Vdd+Vdd-Vdata=Vb-Vdata; thereby, the threshold voltage drift of the driving transistor T3 caused by the data voltage signal of the previous frame or the previous row is eliminated by the variable reverse bias voltage signal, and at the same time, the voltage of the second node N2 connected to the first electrode of the driving transistor T3 and the second electrode of the data writing transistor T4 is reset to the first voltage provided by the first power supply voltage line Vdd.

[0108] In the reset phase (t2), the first reset subcircuit responds to the third scan signal and resets the voltage of the first control terminal of the driving subcircuit through the first initialization signal. At the same time, the second reset subcircuit responds to the third scan signal and initializes the light-emitting device to be driven through the second initialization signal.

[0109] like Figure 9As shown, it is an equivalent circuit diagram of the pixel driving circuit in the reset stage of this embodiment; in this stage, a low-level signal is written to the second light-emitting control line EM1(n), and the second light-emitting control signal provided by the second light-emitting control line EM1(n) turns on the second light-emitting control transistor T6; a low-level signal is written to the third scan line Gate(n-1), and the third scan signal provided by the third scan line Gate(n-1) turns on the second reset transistor T7; the second initialization signal provided by the second initialization signal terminal Vint2 resets the voltage of the third node N3 connecting the second electrode of the driving transistor T3 and the first electrode of the threshold compensation transistor T2 to the voltage of the second initialization signal terminal Vint2; the third scan signal provided by the third scan line Gate(n-1) turns on the first reset transistor T1, and the first initialization signal provided by the first initialization signal terminal Vint1 resets the voltage of the first node N1 connecting the first control electrode of the driving transistor T3 and the second electrode of the threshold compensation transistor T2 to the voltage of the first initialization signal terminal Vint1.

[0110] Simultaneously, during the reset phase (t2), a low-level signal is written to the third scan line Gate(n-1), while high-level signals are written to the first scan line Gate(n), the second scan line Gate(n-2), and the first light-emitting control line EM2(n+1). The first reset transistor T1 and the second reset transistor T7 are turned on, and the first control electrode of the driving transistor T3 is written with the first initialization signal via the first reset transistor T1, via the first reset transistor T1, to prepare for the writing of the next frame data voltage Vdata. The first electrode of the light-emitting device D is written with the second initialization signal via the second reset transistor T7, via the second initialization signal terminal Vint2 (the voltage at the second initialization signal terminal Vinit2 is ≤ VSS). This causes the light-emitting device D to no longer be in the forward conduction state, gradually dissipating the internal electric field formed by the directional migration of impurity ions within the light-emitting device D, thereby restoring the characteristics of the light-emitting device D.

[0111] Optionally, the voltage of the first initialization signal terminal Vint1 is equal to the voltage of the second initialization signal terminal Vint2. In the reset phase, the voltage difference Vgd between the first control electrode and the second electrode of the driving transistor T3 is Vgd=Vint1-Vint2=0V.

[0112] Optionally, in the reset phase, the electric field strength formed by the first initialization signal is smaller than the electric field strength formed by the variable reverse bias voltage signal, and the electric field strength formed by the second initialization signal is smaller than the electric field strength formed by the variable reverse bias voltage signal. This can prevent the electric field conditions that cause the threshold voltage of the driving transistor T3 to drift again due to the voltage at the first initialization signal terminal Vint1 and the voltage at the second initialization signal terminal Vint2 after the threshold voltage drift of the driving transistor T3 is eliminated (ie after the reset phase) from being met.

[0113] In the data writing and threshold compensation stage (t3), the data writing sub-circuit responds to the first scanning signal to write the data voltage signal to the first end of the driving sub-circuit. At the same time, the threshold compensation sub-circuit responds to the first scanning signal to compensate the threshold voltage of the driving sub-circuit.

[0114] like Figure 7 As shown, during the data writing and threshold compensation phase, a low-level signal is written to the first scan line Gate(n), and a high-level signal is written to the second scan line Gate(n-2), the third scan line Gate(n-1), the first light-emitting control line EM2(n+1), and the second light-emitting control line EM1(n); the data writing transistor T4 and the threshold compensation transistor T2 are turned on. The driving transistor T3 is connected by the threshold compensation transistor T2 to form a diode structure. The data voltage Vdata written on the data line Data is written to the first control electrode of the driving transistor T3 through the data writing transistor T4 and the threshold compensation transistor T2 until the driving transistor T3 is turned off. The voltage of the first control electrode of the driving transistor T3 is Vdata+Vth (Vth<0, Vth is the threshold voltage of the driving transistor T3) and is stored in the storage capacitor Cst. The voltages of the first plate and the second plate of the storage capacitor Cst are Vdata+Vth and Vdd, respectively.

[0115] In the light-emitting stage (t4), the first light-emitting control subcircuit responds to the first light-emitting control signal to control the first voltage to be written into the first end of the driving subcircuit. At the same time, the second light-emitting control subcircuit responds to the second light-emitting control signal to turn on the connection between the driving subcircuit and the light-emitting device to be driven.

[0116] like Figure 7 As shown, in the light-emitting phase (t4), low-level signals are written to the first light-emitting control line EM2(n+1) and the second light-emitting control line EM1(n), high-level signals are written to the first scan line Gate(n), the second scan line Gate(n-2), and the third scan line Gate(n-1). The first light-emitting control transistor T5 and the second light-emitting control transistor T6 are both turned on, and the first electrode of the driving transistor T3 is connected to the first power supply voltage line Vdd. The voltage at the first electrode of the driving transistor T3 changes instantaneously from Vdata in the previous phase to Vdd. The light-emitting device D emits light under the drive of the driving transistor T3. At this time, the driving transistor T3 operates in the saturation region. The voltage at the first control electrode of the driving transistor T3 is Vdata+Vth, and the voltage at the first electrode of the driving transistor T3 is Vdd. Therefore, the voltage difference between the first control electrode and the first electrode of the driving transistor T3 is: Vgs=(Vdata+Vth)-Vdd, until the threshold voltage drift elimination phase of the next frame.

[0117] The light-emitting current of the light-emitting device D is equal to the current flowing through the driving transistor T3, and its expression is as follows:

[0118] I D =β(Vgs-Vth) 2

[0119] =β(Vdata+Vth-dd-Vth) 2

[0120] =β(Vdata-Vdd) 2 ;

[0121] in, μ n is the electron mobility of the driving transistor T3, C ox is the insulation capacitance per unit area, is the width-to-length ratio of the driving transistor T3.

[0122] In this embodiment, Figure 7 As shown, the second scan signal (Gate(n-2)), the third scan signal and the first scan signal are input sequentially row by row within one frame display time; the second scan signal is input during the threshold voltage drift elimination stage; the third scan signal is input during the reset stage; and the first scan signal is input during the data writing and threshold compensation stage.

[0123] Among them, the second scan signal is provided by the second scan line Gate (n-2), the third scan signal is provided by the third scan line Gate (n-1), and the first scan signal is provided by the first scan line Gate (n), that is, the second scan line Gate (n-2), the third scan line Gate (n-1) and the first scan line Gate (n) are scanned sequentially line by line within one frame display time.

[0124] Optionally, the first light-emitting control signal (provided by the first light-emitting control line EM2(n+1)) is input in the threshold voltage drift elimination stage and the light-emitting stage; the second light-emitting control signal (provided by the second light-emitting control line EM1(n)) is input in the reset stage and the light-emitting stage.

[0125] The pixel driving circuit provided in this embodiment, by setting a threshold voltage drift elimination sub-circuit, can improve or eliminate the threshold voltage drift of the driving sub-circuit caused by the data voltage signal when the data voltage signal changes, and limit the threshold voltage drift range of the driving sub-circuit, stabilize the driving of the driving sub-circuit, and improve or eliminate the light-emitting hysteresis problem of the light-emitting device. At the same time, the reverse bias voltage signal is variable in size according to the different degrees of threshold voltage drift of the driving sub-circuit caused by data voltage signals of different sizes, thereby more accurately improving or eliminating the different degrees of threshold voltage drift of the driving sub-circuit with the change of the data voltage signal, so that the threshold voltage drift of the driving sub-circuit is always maintained in a dynamic balance process, thereby ensuring the stable driving of the pixel driving circuit, improving or eliminating the light-emitting hysteresis problem of the light-emitting device, and improving or avoiding the appearance of afterimages on the display screen.

[0126] An embodiment of the present invention further provides a display panel, comprising a plurality of pixel units, each of the plurality of pixel units comprising a pixel driving circuit and a light-emitting device; the pixel driving circuit is any one of the above-mentioned pixel driving circuits.

[0127] By adopting the pixel driving circuit in the above embodiment, the display stability and display effect of the display panel are improved.

[0128] Among them, the display panel can be a liquid crystal display device or an electroluminescent display device, such as a liquid crystal panel, an OLED panel, a Micro LED panel, a Mini LED panel, a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, or any other product or component with a display function.

[0129] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A pixel driving circuit, comprising: data writing sub-circuit, threshold compensation sub-circuit, driving sub-circuit and storage sub-circuit; wherein, The data writing sub-circuit is configured to transmit the data voltage signal to the first terminal of the driving sub-circuit in response to the first scanning signal; The threshold compensation sub-circuit is configured to compensate the threshold voltage of the driving sub-circuit in response to the first scanning signal; The storage sub-circuit is configured to store the data voltage signal; The driving sub-circuit is configured to provide a driving current to the light-emitting device to be driven according to the voltages at the first terminal and the first control terminal; It is characterized by further comprising a threshold voltage drift elimination sub-circuit, configured to transmit a variable reverse bias voltage signal to the second control terminal of the driving sub-circuit in response to a second scanning signal; The variable reverse bias voltage signal has a polarity opposite to that of the data voltage signal and is used to eliminate a threshold voltage drift of the driving sub-circuit caused by the data voltage signal of a previous frame or a previous row; The threshold voltage drift elimination sub-circuit includes an eighth transistor, a control electrode of the eighth transistor is connected to the second scan line, a first electrode of the eighth transistor is connected to the second control terminal of the driving sub-circuit, and a second electrode of the eighth transistor is connected to the data line.

2. The pixel driving circuit according to claim 1, wherein: The driving sub-circuit includes a driving transistor, The first electrode of the driving transistor is used as the first terminal of the driving sub-circuit, the second electrode of the driving transistor is used as the second terminal of the driving sub-circuit, the first control electrode of the driving transistor is used as the first control terminal of the driving sub-circuit, and the second control electrode of the driving transistor is used as the second control terminal of the driving sub-circuit; A PNP transistor is formed between the first control electrode of the driving transistor and the first electrode and the second electrode, and an NPN transistor is formed between the second control electrode of the driving transistor and the first electrode and the second electrode; Alternatively, an NPN transistor is formed between the first control electrode of the driving transistor and the first electrode and the second electrode, and a PNP transistor is formed between the second control electrode of the driving transistor and the first electrode and the second electrode.

3. The pixel driving circuit according to claim 2, wherein: The threshold compensation sub-circuit includes a threshold compensation transistor, the data writing sub-circuit includes a data writing transistor, and the storage sub-circuit includes a storage capacitor; The first electrode of the driving transistor is connected to the second electrode of the data writing transistor, the second electrode of the driving transistor is connected to the first electrode of the threshold compensation transistor, the first control electrode of the driving transistor is connected to the second electrode of the threshold compensation transistor and the first plate of the storage capacitor, and the second control electrode of the driving transistor is connected to the first electrode of the eighth transistor; A first electrode of the data writing transistor is connected to the data line, and a control electrode of the data writing transistor is connected to the first scan line; The control electrode of the threshold compensation transistor is connected to the first scan line; The second plate of the storage capacitor is connected to the first power supply voltage line.

4. The pixel driving circuit according to any one of claims 1 to 3, characterized in that: Also includes: The first light-emitting control sub-circuit is configured to control whether a first voltage can be written into the first terminal of the driving sub-circuit in response to a first light-emitting control signal.

5. The pixel driving circuit according to claim 4, wherein: The first light emission control subcircuit includes a first light emission control transistor; A first electrode of the first light-emitting control transistor is connected to a first power supply voltage line, a second electrode of the first light-emitting control transistor is connected to a first end of the driving sub-circuit, and a control electrode of the first light-emitting control transistor is connected to a first light-emitting control line.

6. The pixel driving circuit according to claim 4, wherein: Also includes: The first reset sub-circuit is configured to respond to the third scan signal and reset the voltage of the first control terminal of the driving sub-circuit through the first initialization signal.

7. The pixel driving circuit according to claim 6, wherein: The first reset subcircuit includes a first reset transistor; A first electrode of the first reset transistor is connected to a first initialization signal terminal, a second electrode of the first reset transistor is connected to a first control terminal of the driving sub-circuit, and a control electrode of the first reset transistor is connected to a third scan line.

8. The pixel driving circuit according to claim 6, wherein: Also includes: The second light-emitting control sub-circuit is configured to switch on or off the connection between the driving sub-circuit and the light-emitting device to be driven in response to a second light-emitting control signal.

9. The pixel driving circuit according to claim 8, wherein: The second light emitting control subcircuit includes a second light emitting control transistor; The first electrode of the second light emitting control transistor is connected to the second end of the driving sub-circuit, the second electrode of the second light emitting control transistor is connected to the first electrode of the light emitting device to be driven, and the control electrode of the second light emitting control transistor is connected to the second light emitting control line.

10. The pixel driving circuit according to claim 8, wherein: Also includes: The second reset sub-circuit is configured to initialize the light-emitting device to be driven through a second initialization signal in response to the third scan signal.

11. The pixel driving circuit according to claim 10, wherein: The second reset sub-circuit includes a second reset transistor; A first electrode of the second reset transistor is connected to the first electrode of the light-emitting device to be driven, a second electrode of the second reset transistor is connected to a second initialization signal terminal, and a control electrode of the second reset transistor is connected to a third scan line.

12. A display panel comprising a plurality of pixel units, each of the plurality of pixel units comprising a pixel driving circuit and a light emitting device; It is characterized by: The pixel driving circuit comprises the pixel driving circuit according to any one of claims 1 to 11.

13. A driving method for a pixel driving circuit according to claim 10, characterized in that: include: In the threshold voltage drift elimination stage, the threshold voltage drift elimination sub-circuit writes the variable reverse bias voltage signal input on the data line to the second control terminal of the driving sub-circuit in response to the second scanning signal, so as to eliminate the threshold voltage drift of the driving sub-circuit caused by the data voltage signal of the previous frame or the previous row input on the data line; In the reset phase, the first reset subcircuit, in response to the third scan signal, resets the voltage of the first control terminal of the driving subcircuit through the first initialization signal. At the same time, the second reset subcircuit, in response to the third scan signal, initializes the light-emitting device to be driven through the second initialization signal. In the data writing and threshold compensation stage, the data writing sub-circuit writes the data voltage signal to the first end of the driving sub-circuit in response to the first scanning signal, and at the same time, the threshold compensation sub-circuit compensates the threshold voltage of the driving sub-circuit in response to the first scanning signal; During the light-emitting stage, the first light-emitting control subcircuit responds to the first light-emitting control signal to control the first voltage to be written into the first end of the driving subcircuit. At the same time, the second light-emitting control subcircuit responds to the second light-emitting control signal to turn on the connection between the driving subcircuit and the light-emitting device to be driven.

14. The driving method of the pixel driving circuit according to claim 13, wherein: The second scanning signal, the third scanning signal and the first scanning signal are input sequentially line by line within one frame display time; The second scanning signal is input during the threshold voltage drift elimination phase; The third scanning signal is input during the reset phase; The first scanning signal is input during the data writing and threshold compensation phase.

15. The driving method of the pixel driving circuit according to claim 13, wherein: The first light-emitting control signal is input during the threshold voltage drift elimination phase and the light-emitting phase; The second light emitting control signal is input during a reset phase and a light emitting phase.

16. The driving method of the pixel driving circuit according to claim 13, wherein: The electric field strength formed by the first initialization signal is smaller than the electric field strength formed by the variable reverse bias voltage signal. The electric field strength formed by the second initialization signal is smaller than the electric field strength formed by the variable reverse bias voltage signal.

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