A pixel driving circuit and its driving method and debugging method

Abstract

The present invention discloses a pixel driving circuit and its driving and debugging methods. The pixel driving circuit includes a first data writing module, a second data writing module, a first storage module, a second storage module, a leakage current control module, a driving transistor, and a light-emitting module. The first data writing module is used to write a pull-down data voltage into the first storage module; the second data writing module is used to write a display data voltage into the second storage module and the driving transistor; the leakage current control module is used to control the magnitude of the leakage current between the first storage module and the second storage module to control the time for the second storage module to discharge into the first storage module; the driving transistor is used to generate a driving current based on the display data voltage and control its own conduction time based on the time for the second storage module to discharge into the first storage module; and the light-emitting module is used to emit light based on the driving current and the conduction time. The present invention achieves the effect of improving the display uniformity of the display panel.

Description

Technical Field

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

[0002] With the development of display technology, the application of display panels is becoming more and more extensive, and correspondingly, the requirements for display panels are becoming higher and higher.

[0003] Existing display panels have uneven display due to uneven manufacturing during the manufacturing process. Summary of the Invention

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

[0005] In a first aspect, an embodiment of the present invention provides a pixel driving circuit, the pixel driving circuit comprising: a first data writing module, a second data writing module, a first storage module, a second storage module, a leakage current control module, a driving transistor, and a light emitting module;

[0006] The first data writing module is used to write the pull-down data voltage into the first storage module;

[0007] The second data writing module is used to write the display data voltage into the second storage module and the control terminal of the driving transistor;

[0008] The leakage current control module is connected between the first storage module and the second storage module, and is used to control the magnitude of the leakage current between the first storage module and the second storage module when the light-emitting module emits light, so as to control the time for the second storage module to discharge into the first storage module;

[0009] The driving transistor is used to generate a driving current according to the display data voltage and control its own conduction time according to the time when the second storage module discharges to the first storage module;

[0010] The light emitting module is configured to emit light according to the driving current and the on-time.

[0011] Optionally, a control terminal of the first data writing module is connected to a first scanning signal, a first terminal of the first data writing module is connected to a pull-down data voltage writing terminal, a second terminal of the first data writing module is electrically connected to a first terminal of the first storage module, a second terminal of the first storage module is grounded, and the first data writing module is used to write the pull-down data voltage into the first terminal of the first storage module;

[0012] The control end of the second data writing module is connected to the second scanning signal, the first end of the second data writing module is connected to the display data voltage writing end, the second end of the second data writing module is electrically connected to the control end of the driving transistor, the second end of the second data writing module is also electrically connected to the first end of the second storage module, the second end of the second storage module is electrically connected to the first end of the driving transistor, and the second data writing module is used to write the display data voltage into the control end of the driving transistor and the second storage module;

[0013] The control end of the leakage current control module receives a control signal, the first end of the leakage current control module is electrically connected to the first end of the first storage module, and the second end of the leakage current control module is electrically connected to the first end of the second storage module;

[0014] The first end of the driving transistor is connected to a first power signal, the second end of the driving transistor is electrically connected to the first end of the light emitting module, and the second end of the light emitting module is connected to a second power signal.

[0015] The leakage current control module can control the leakage current between the first storage module and the second storage module, so as to control the time for the second storage module to discharge to the first storage module, thereby controlling the on-time of the driving transistor.

[0016] Optionally, the leakage current control module includes at least one leakage current control transistor;

[0017] The leakage current control transistor is connected between the first end of the first storage module and the first end of the second storage module, and the control end of the leakage current control transistor is the control end of the leakage current control module.

[0018] By controlling the number of on and off states of the leakage current control transistor, the magnitude of the leakage current between the first storage module and the second storage module can be controlled.

[0019] Optionally, the leakage current control module further includes at least one third storage module;

[0020] A first terminal of the third storage module is electrically connected to the control terminal of the leakage current control transistor, and a second terminal of the third storage module is connected to the first power signal.

[0021] The third storage module is provided in a one-to-one correspondence with the leakage current control transistor. The third storage module can maintain the potential of the control terminal of the leakage current control transistor, so as to make the light emitting module display the desired brightness.

[0022] Optionally, the leakage current control module includes at least two leakage current control transistors;

[0023] The at least two leakage current control transistors are connected in series between the first end of the first storage module and the first end of the second storage module, and each of the leakage current control transistors has a different channel width-to-length ratio.

[0024] By controlling the channel width-to-length ratios of the leakage current control transistors to be different, the magnitude of the leakage current between the first storage module and the second storage module can be controlled.

[0025] Optionally, the leakage current control module includes a leakage current control transistor;

[0026] The leakage current control transistor is connected between the first end of the first storage module and the first end of the second storage module. The control end of the leakage current control transistor is connected to a control signal. The leakage current control transistor is used to adjust its own channel width-to-length ratio according to the control signal when the light-emitting module emits light.

[0027] By adjusting the channel width-to-length ratio of the leakage current control transistor, the leakage current of the leakage current control transistor can be adjusted, thereby controlling the time for the second storage module to discharge into the first storage module.

[0028] Optionally, the first storage module includes a first capacitor;

[0029] The first end of the first capacitor is the first end of the first storage module, and the second end of the first capacitor is the second end of the first storage module;

[0030] And / or, the second storage module includes a second capacitor;

[0031] The first end of the second capacitor is the first end of the second storage module, and the second end of the second capacitor is the second end of the second storage module.

[0032] The first capacitor can store the pull-down data voltage, and the second capacitor can store the display data voltage of the driving transistor. By controlling the time when the second capacitor discharges to the first capacitor, the on-time of the driving transistor can be controlled.

[0033] Optionally, the pixel driving circuit further includes a light emitting control module;

[0034] The second end of the driving transistor is electrically connected to the first end of the light emitting module through the light emitting control module. The control end of the light emitting control module is connected to an enable signal. The light emitting control module is used to control the light emitting module to emit light according to the enable signal.

[0035] The light emitting control module can control the light emitting module to obtain the driving current generated by the driving transistor, thereby controlling the light emitting module to emit light.

[0036] In a second aspect, an embodiment of the present invention further provides a driving method for a pixel driving circuit, wherein the driving method is used to drive any pixel driving circuit described in the first aspect, and the driving method for the pixel driving circuit includes:

[0037] In the data writing phase, the first data writing module writes the pull-down data voltage into the first storage module, and the second data writing module writes the display data voltage into the second storage module and into the control terminal of the driving transistor;

[0038] In the light-emitting stage, the driving transistor generates a driving current according to the display data voltage, the leakage current control module controls the magnitude of the leakage current between the first storage module and the second storage module according to a control signal to control the time for the second storage module to discharge into the first storage module, the driving transistor controls the on-time of the driving transistor according to the time for the second storage module to discharge into the first storage module, and the light-emitting module emits light according to the driving current and the on-time.

[0039] In a third aspect, an embodiment of the present invention further provides a method for debugging a pixel driving circuit, the method being used to debug any pixel driving circuit described in the first aspect, the method comprising:

[0040] In the data writing phase, the first data writing module writes the reference pull-down data voltage into the first storage module, and the second data writing module writes the display data voltage into the second storage module and into the control terminal of the driving transistor;

[0041] In a light-emitting stage, the driving transistor generates a driving current according to the display data voltage, the leakage current control module controls the magnitude of the leakage current between the first end of the first storage module and the first end of the second storage module according to a control signal, so as to control the time for the second storage module to discharge into the first storage module, the driving transistor controls the on-time of the driving transistor to be a first time length according to the time for the second storage module to discharge into the first storage module, and the light-emitting module emits light according to the driving current and the first time length;

[0042] When the light-emitting module emits light, detecting a display brightness value of the light-emitting module;

[0043] In the data adjustment stage, the reference pull-down data voltage is adjusted to a second pull-down data voltage according to the display brightness value and the brightness value to be displayed, so that the pixel driving circuit drives the light emitting module to display the brightness value to be displayed according to the second pull-down data voltage and the display data voltage.

[0044] In the present invention, a pixel driving circuit includes: a first data writing module, a second data writing module, a first storage module, a second storage module, a leakage current control module, a driving transistor, and a light-emitting module. The driving transistor can generate a corresponding driving current according to a display data voltage, and the light-emitting module emits light in response to the driving current. The first storage module and the second storage module are connected via a leakage current control module. Since the pull-down data voltage stored in the first storage module is relatively small, the second storage module discharges the data into the first storage module. The leakage current control module can then control the magnitude of the leakage current between the first and second storage modules and the time when the second storage module discharges the data into the first storage module, thereby controlling the on-time of the driving transistor and the light-emitting duration of the light-emitting module, thereby displaying a desired brightness. Furthermore, by inputting different pull-down data voltages, the time when the second storage module discharges the data into the first storage module can be controlled, thereby controlling the on-time of the driving transistor and the light-emitting duration of the light-emitting module, thereby displaying different display brightnesses. Therefore, by controlling the pull-down data voltage of each pixel unit in the display panel and controlling the leakage current between the first storage module and the second storage module of all pixel units through the leakage current control module, the light-emitting duration of the light-emitting module in each pixel unit can be controlled. That is, the light-emitting duration of all pixel units can be accurately controlled, so that each pixel unit can display the desired brightness, thereby achieving the effect of improving the display uniformity of the display panel. The present invention solves the problem of uneven display of the display panel and achieves the effect of improving the display uniformity of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 1 is a schematic structural diagram of a pixel driving circuit provided by an embodiment of the present invention;

[0046] Figure 2 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0047] Figure 3 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0048] Figure 4 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0049] Figure 5 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention;

[0050] Figure 6 is a flow chart of a driving method of a pixel driving circuit provided by an embodiment of the present invention;

[0051] Figure 7is a timing diagram corresponding to a pixel driving circuit provided by an embodiment of the present invention;

[0052] Figure 8 is a timing diagram corresponding to another pixel driving circuit provided by an embodiment of the present invention;

[0053] Figure 9 This is a flowchart of a debugging method for a pixel driving circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0054] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0055] As mentioned in the background technology, existing display panels have the problem of uneven display. After careful research, the applicant found that the cause of this technical problem is that the display panel has uneven manufacturing process and there are batch transfer differences in the transfer process of the light-emitting diodes (such as Micro LEDs) in the display panel, resulting in uneven display of the display panel. The pixel driving circuit of the existing display panel improves uniformity by controlling the magnitude of the compensation current input to the pixel unit to compensate the driving current. However, calculating the compensation current is cumbersome and is affected by leakage current, making it difficult to accurately determine the magnitude of the compensation current.

[0056] In view of the above problems, an embodiment of the present invention provides a pixel driving circuit. Figure 1 This is a schematic diagram of a pixel driving circuit according to an embodiment of the present invention. Figure 1The pixel driving circuit includes: a first data writing module 101, a second data writing module 102, a first storage module 103, a second storage module 104, a leakage current control module 105, a driving transistor T0 and a light-emitting module 106; the first data writing module 101 is used to write the pull-down data voltage Vdata1 into the first storage module 103; the second data writing module 102 is used to write the display data voltage Vdata2 into the second storage module 104 and the control end of the driving transistor T0; the leakage current control module 105 is connected between the first storage module 103 and the second storage module 104, and is used to control the leakage current between the first storage module 103 and the second storage module 104 when the light-emitting module 106 emits light, so as to control the discharge time of the second storage module 104 into the first storage module 103; the driving transistor T0 is used to generate a driving current according to the display data voltage Vdata2 and control its own conduction time according to the discharge time of the second storage module 104 to the first storage module 103; the light-emitting module 106 is used to emit light according to the driving current and the conduction time.

[0057] Specifically, the light-emitting module 106 may be, for example, an OLED (Organic Light-Emitting Diode). An OLED is a current-mode device that requires a driving current to emit light. The driving transistor T0 can generate a corresponding driving current based on the display data voltage Vdata2, and the light-emitting module 106 emits light in response to the driving current. Furthermore, the first storage module 103 and the second storage module 104 are connected via a leakage current control module 105. Because the pull-down data voltage Vdata1 stored in the first storage module 103 is relatively small, the second storage module 104 discharges the light into the first storage module 103. The leakage current control module 105 then controls the magnitude of the leakage current between the first storage module 103 and the second storage module 104, and the duration of the discharge from the second storage module 104 to the first storage module 103. This, in turn, controls the on-time of the driving transistor T0, thereby controlling the duration of the light-emitting module 106's light emission, thereby displaying the desired brightness. Furthermore, by inputting different pull-down data voltages Vdata1, the voltage difference between the first storage module 103 and the second storage module 104 can be controlled, and the time for the second storage module 104 to discharge into the first storage module 103 can also be controlled, thereby controlling the on-time of the driving transistor T0, and thus controlling the light-emitting duration of the light-emitting module 106, thereby displaying different display brightnesses. Therefore, by controlling the pull-down data voltage Vdata1 of each pixel unit in the display panel and controlling the leakage current between the first storage module 103 and the second storage module 104 of all pixel units through the leakage current control module 105, the light-emitting duration of the light-emitting module 106 in each pixel unit can be controlled. That is, the light-emitting duration of all pixel units can be accurately controlled, so that each pixel unit can display the desired brightness, thereby achieving the effect of improving the display uniformity of the display panel.

[0058] In addition, the brightness corresponding to the pixel units at different positions on the display panel may be different. By setting different pull-down data voltages Vdata1, each pixel unit can display the brightness to be displayed. However, the control signal of the leakage current control module 105 in the pixel units at different positions can be the same or different, that is, in the pixel units at different positions, the leakage current between the first storage module 103 and the second storage module 104 controlled by the leakage current control module 105 can be the same or different. It can be specifically determined according to the actual brightness to be displayed and is not limited here.

[0059] The technical solution of this embodiment includes a pixel driving circuit comprising: a first data writing module, a second data writing module, a first storage module, a second storage module, a leakage current control module, a driving transistor, and a light-emitting module. The driving transistor can generate a corresponding driving current according to a display data voltage, and the light-emitting module emits light in response to the driving current. The first storage module and the second storage module are connected via a leakage current control module. Since the pull-down data voltage stored in the first storage module is relatively small, the second storage module discharges the light into the first storage module. The leakage current control module can then control the magnitude of the leakage current between the first and second storage modules and the time during which the second storage module discharges the light into the first storage module, thereby controlling the on-time of the driving transistor and the duration of the light-emitting module, thereby displaying a desired brightness. Furthermore, by inputting different pull-down data voltages, the time during which the second storage module discharges the light into the first storage module can be controlled, thereby controlling the on-time of the driving transistor and the duration of the light-emitting module, thereby displaying different brightness levels. Therefore, by controlling the pull-down data voltage of each pixel unit in the display panel and controlling the leakage current between the first storage module and the second storage module of all pixel units through the leakage current control module, the light-emitting duration of the light-emitting module in each pixel unit can be controlled. That is, the light-emitting duration of all pixel units can be accurately controlled, so that each pixel unit can display the desired brightness, thereby achieving the effect of improving the display uniformity of the display panel. The technical solution of this embodiment solves the problem of uneven display of the display panel and achieves the effect of improving the display uniformity of the display panel.

[0060] Continue to refer Figure 1The control end of the first data writing module 101 is connected to the first scan signal Scan1, the first end of the first data writing module 101 is connected to the pull-down data voltage writing end V1, the second end of the first data writing module 101 is electrically connected to the first end of the first storage module 103, the second end of the first storage module 103 is grounded, and the first data writing module 101 is used to write the pull-down data voltage Vdata1 into the first end of the first storage module 103; the control end of the second data writing module 102 is connected to the second scan signal Scan2, the first end of the second data writing module 102 is connected to the display data voltage writing end V2, the second end of the second data writing module 102 is electrically connected to the control end of the driving transistor T0, and the second end of the second data writing module 102 is also connected to the control end of the driving transistor T0. The first end of the second storage module 104 is electrically connected, the second end of the second storage module 104 is electrically connected to the first end of the driving transistor T0, and the second data writing module 102 is used to write the display data voltage Vdata2 into the control end of the driving transistor T0 and the second storage module 104; the control end of the leakage current control module 105 is connected to the control signal VG, the first end of the leakage current control module 105 is electrically connected to the first end of the first storage module 103, and the second end of the leakage current control module 105 is electrically connected to the first end of the second storage module 104; the first end of the driving transistor T0 is connected to the first power supply signal VDD, the second end of the driving transistor T0 is electrically connected to the first end of the light-emitting module 106, and the second end of the light-emitting module 106 is connected to the second power supply signal VSS.

[0061] Specifically, the second end of the first data writing module 101 is electrically connected to the first end of the first storage module 103, so that the first storage module 103 can store the pull-down data voltage Vdata1. The second end of the second data writing module 102 is electrically connected to the control end of the driving transistor T0. The second end of the second data writing module 102 is also electrically connected to the first end of the second storage module 104, so that the second storage module 104 can store the display data voltage Vdata2 of the driving transistor T0. The control signal VG can be used to control the conduction or cutoff of the leakage current control module 105, so that the leakage current control module 105 can control the leakage current between the first storage module 103 and the second storage module 104, so as to control the discharge time of the second storage module 104 to the first storage module 103, thereby controlling the conduction time of the driving transistor T0, and thus controlling the light-emitting duration of the light-emitting module 106, thereby displaying different display brightness.

[0062] Optionally, the pull-down data voltage writing terminal V1 and the display data voltage writing terminal V2 are the same terminal, that is, the pull-down data voltage Vdata1 and the display data voltage Vdata2 can be written by the same data line, which can reduce the number of data lines, reduce the wiring of the display panel, and achieve the effect of simplifying the layout.

[0063] Figure 2 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 2 The leakage current control module 105 includes at least one leakage current control transistor T1; the leakage current control transistor T1 is connected between the first end of the first storage module 103 and the first end of the second storage module 104, and the control end of the leakage current control transistor T1 is the control end of the leakage current control module 105.

[0064] Specifically, the leakage current control module 105 may include multiple leakage current control transistors T1. When a large number of leakage current control transistors T1 are turned on, the leakage current between the first storage module 103 and the second storage module 104 is small. When a large number of leakage current control transistors T1 are turned off, the leakage current between the first storage module 103 and the second storage module 104 is large. When all leakage current control transistors T1 are turned on, the leakage current between the first storage module 103 and the second storage module 104 is minimum. Therefore, by controlling the number of leakage current control transistors T1 that are turned on and off, the size of the leakage current between the first storage module 103 and the second storage module 104 can be controlled. Figure 2 The figure only shows the case where the leakage current control module 105 includes two leakage current control transistors T1, but this is not limiting. It should be noted that the control signals VG at the control terminals of different leakage current control transistors T1 are different. When two leakage current control transistors T1 are included, the control terminals of the two leakage current control transistors T1 are connected to the control signals VG1 and VG2, respectively.

[0065] Alternatively, see Figure 2 The leakage current control module 105 further includes at least one third storage module 1051 ; a first end of the third storage module 1051 is electrically connected to the control end of the leakage current control transistor T1 , and a second end of the third storage module 1051 is connected to the first power signal VDD.

[0066] Specifically, the third storage module 1051 is set in a one-to-one correspondence with the leakage current control transistor T1. The third storage module 1051 can maintain the potential of the control end of the leakage current control transistor T1, so that the leakage current control transistor T1 can work stably for a long time, making it easier for the light-emitting module 106 to display the brightness to be displayed.

[0067] Alternatively, see Figure 2 The leakage current control module 105 includes at least two leakage current control transistors T1; at least two leakage current control transistors T1 are connected in series between the first end of the first storage module 103 and the first end of the second storage module 104, and each leakage current control transistor T1 has a different channel width-to-length ratio.

[0068] Specifically, the larger the channel width-to-length ratio of the leakage current control transistor T1, the larger the leakage current generated; the smaller the channel width-to-length ratio of the leakage current control transistor T1, the smaller the leakage current generated. The channel width-to-length ratio of each leakage current control transistor T1 is different, so by controlling the conduction or cutoff of each leakage current control transistor T1, the size of the leakage current between the first storage module 103 and the second storage module 104 can be controlled, thereby controlling the discharge time of the second storage module 104 to the first storage module 103.

[0069] Figure 3 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 3 The leakage current control module 105 includes a first leakage current control transistor T11, a second leakage current control transistor T12, a third leakage current control transistor T13, a fourth leakage current control transistor T14, a fifth leakage current control transistor T15, a sixth leakage current control transistor T16, a seventh leakage current control transistor T17, and an eighth leakage current control transistor T18. The control terminal of the first leakage current control transistor T11 is connected to the first control signal VG11, the control terminal of the second leakage current control transistor T12 is connected to the second control signal VG12, the control terminal of the third leakage current control transistor T13 is connected to the third control signal VG13, the control terminal of the fourth leakage current control transistor T14 is connected to the fourth control signal VG14, the control terminal of the fifth leakage current control transistor T15 is connected to the fifth control signal VG15, the control terminal of the sixth leakage current control transistor T16 is connected to the sixth control signal VG16, the control terminal of the seventh leakage current control transistor T17 is connected to the seventh control signal VG17, and the control terminal of the eighth leakage current control transistor T18 is connected to the eighth control signal VG18.

[0070] Specifically, by providing eight leakage current control transistors, each having a different channel width-to-length ratio, the leakage current of leakage current control module 105 has a wide adjustment range, facilitating the realization of all display grayscales, making the display panel more accurate, and facilitating improved display effects. By inputting different control signals, the number of times the leakage current control transistors are turned on and off is controlled, and the corresponding leakage current is output, thereby controlling the magnitude of the leakage current between the first storage module 103 and the second storage module 104, thereby controlling the on-time of the driving transistor T0 and the light-emitting duration of the light-emitting module 106, facilitating the realization of the brightness to be displayed and improving display uniformity.

[0071] Alternatively, see Figure 3The leakage current control module 105 also includes a first switch transistor M1, a second switch transistor M2, a third switch transistor M3, a fourth switch transistor M4, a fifth switch transistor M5, a sixth switch transistor M6, a seventh switch transistor M7 and an eighth switch transistor M8. The control end of the first leakage current control transistor T11 is connected to the first control signal VG11 through the first switch transistor M1, the control end of the first switch transistor M1 is connected to the control signal VM1, the control end of the second leakage current control transistor T12 is connected to the second control signal VG12 through the second switch transistor M2, the control end of the second switch transistor M2 is connected to the control signal VM2, the control end of the third leakage current control transistor T13 is connected to the third control signal VG13 through the third switch transistor M3, the control end of the third switch transistor M3 is connected to the control signal VM3, and the control end of the fourth leakage current control transistor T14 is connected to the control signal VG15. The fourth control signal VG14 is connected to the control end of the fourth switch transistor M4, the control end of the fourth switch transistor M4 is connected to the control signal VM4, the control end of the fifth leakage current control transistor T15 is connected to the fifth control signal VG15 through the fifth switch transistor M5, the control end of the fifth switch transistor M5 is connected to the control signal VM5, the control end of the sixth leakage current control transistor T16 is connected to the sixth control signal VG16 through the sixth switch transistor M6, the control end of the sixth switch transistor M6 is connected to the control signal VM6, the control end of the seventh leakage current control transistor T17 is connected to the seventh control signal VG17 through the seventh switch transistor M7, the control end of the seventh switch transistor M7 is connected to the control signal VM7, the control end of the eighth leakage current control transistor T18 is connected to the eighth control signal VG18 through the eighth switch transistor M8, and the control end of the eighth switch transistor M8 is connected to the control signal VM8.

[0072] Alternatively, see Figure 3 The third storage module 1051 includes a third capacitor C3 , a first end of the third capacitor C3 is the first end of the third storage module 1051 , and a second end of the third capacitor C3 is the second end of the third storage module 1051 .

[0073] Figure 4 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 4 The leakage current control module 105 includes a leakage current control transistor T2; the leakage current control transistor T2 is connected between the first end of the first storage module 103 and the first end of the second storage module 104, and the control end of the leakage current control transistor T2 is connected to the control signal VG. The leakage current control transistor T2 is used to adjust its own channel width-to-length ratio according to the control signal VG when the light-emitting module 106 emits light.

[0074] Specifically, the leakage current control module 105 may also include only one leakage current control transistor T2, and the channel width-to-length ratio of the leakage current control transistor T2 is adjustable, so that the corresponding control signal VG can be input according to the brightness to be displayed, and the potential of the control end of the leakage current control transistor T2 can be adjusted, thereby controlling the channel opening degree of the leakage current control transistor T2, thereby adjusting the channel width-to-length ratio of the leakage current control transistor T2. The channel width-to-length ratio of the leakage current control transistor T2 is positively correlated with the magnitude of the leakage current generated by it. Therefore, by adjusting the channel width-to-length ratio of the leakage current control transistor T2, the magnitude of the leakage current of the leakage current control transistor T2 can be adjusted, thereby controlling the time for the second storage module 104 to discharge to the first storage module 103, thereby controlling the conduction time of the driving transistor T0, thereby controlling the light-emitting duration of the light-emitting module 106, thereby displaying different display brightness, and achieving the effect of simplifying the circuit.

[0075] Figure 5 is a structural diagram of another pixel driving circuit provided by an embodiment of the present invention. Figure 5 , the first storage module 103 includes a first capacitor C1; the first end of the first capacitor C1 is the first end of the first storage module 103, and the second end of the first capacitor C1 is the second end of the first storage module 103; and / or, the second storage module 104 includes a second capacitor C2; the first end of the second capacitor C2 is the first end of the second storage module 104, and the second end of the second capacitor C2 is the second end of the second storage module 104.

[0076] For example, assuming that the capacity of the second capacitor C2 is C, the resistance of the second capacitor C2 is R, and the threshold voltage of the driving transistor T0 is Vt, that is, when the discharge of the second capacitor C2 is less than Vt, the driving transistor T0 is cut off. According to the capacitor discharge formula, it can be seen that the discharge time of the second capacitor C2 is t=RC×Ln[(Vdata1-Vdata2) / (Vdata1-Vt)], that is, the turn-on time of the driving transistor T0 is t=RC×Ln[(Vdata1-Vdata2) / (Vdata1-Vt)]. According to the calculation formula of the turn-on time, it can be seen that by adjusting the pull-down data voltage Vdata1, the turn-on time of the driving transistor T0 can be adjusted, and the light-emitting module 106 can be controlled to display the brightness to be displayed. Furthermore, assuming that the discharge current at the start of discharge of the second capacitor C2 is I1 and the discharge current at the end of discharge is I2, the discharge duration of the second capacitor C2 can be expressed as t = RC × Ln (I2 / I1). Therefore, by adjusting the leakage current between the first capacitor C1 and the second capacitor C2, the discharge current I1 at the start of discharge of the second capacitor C2 can be adjusted, thereby adjusting the discharge duration of the second capacitor C2. Therefore, the discharge duration of the second capacitor C2 can be controlled by adjusting the pull-down data voltage Vdata1 written into the first capacitor C1 to control the on-time of the driving transistor T0; the leakage current control module 105 can also control the leakage current between the first capacitor C1 and the second capacitor C2 to control the discharge duration of the second capacitor C2 to control the on-time of the driving transistor T0; the pull-down data voltage Vdata1 and the leakage current between the first capacitor C1 and the second capacitor C2 can also be simultaneously adjusted to control the discharge duration of the second capacitor C2 to control the on-time of the driving transistor T0, thereby controlling the brightness to be displayed by the light-emitting module 106.

[0077] Alternatively, see Figure 5 The pixel driving circuit also includes a light emitting control module 107; the second end of the driving transistor T0 is electrically connected to the first end of the light emitting module 106 through the light emitting control module 107, and the control end of the light emitting control module 107 is connected to the enable signal EM1. The light emitting control module 107 is used to control the light emitting module 106 to emit light according to the enable signal EM1.

[0078] Specifically, after the display data voltage Vdata2 is written into the driving transistor T0 , the enable signal EM1 controls the light emitting control module 107 to be turned on, so that the light emitting module 106 can obtain the driving current generated by the driving transistor T0 , thereby controlling the light emitting module 106 to emit light.

[0079] Alternatively, see Figure 5The first data writing module 101 includes a first transistor T3, the first end of the first transistor T3 is the first end of the first data writing module 101, the second end of the first transistor T3 is the second end of the first data writing module 101, and the control end of the first transistor T3 is the control end of the first data writing module 101.

[0080] Alternatively, see Figure 5 The second data writing module 102 includes a second transistor T4, the first end of the second transistor T4 is the first end of the second data writing module 102, the second end of the second transistor T4 is the second end of the second data writing module 102, and the control end of the second transistor T4 is the control end of the second data writing module 102.

[0081] Alternatively, see Figure 5 The light control module 107 includes a third transistor T5, a first end of the third transistor T5 is the first end of the light control module 107, a second end of the third transistor T5 is the second end of the light control module 107, and a control end of the third transistor T5 is the control end of the light control module 107.

[0082] Alternatively, see Figure 5 The light-emitting module 106 includes an organic light-emitting diode D1. The anode of the organic light-emitting diode D1 is the first end of the light-emitting module 106, and the cathode of the organic light-emitting diode D1 is the second end of the light-emitting module 106. It is understood that the light-emitting module 106 can also be a Micro LED. The specific configuration can be based on actual conditions and is not specifically limited here.

[0083] Figure 6 is a flowchart of a driving method of a pixel driving circuit provided by an embodiment of the present invention, see Figure 6 The driving method of the pixel driving circuit is used to drive the pixel driving circuit described in any of the above embodiments, and the driving method of the pixel driving circuit includes:

[0084] S601 , in the data writing phase, the first data writing module writes the pull-down data voltage into the first storage module, and the second data writing module writes the display data voltage into the second storage module and into the control terminal of the driving transistor.

[0085] Specifically, Figure 7 This is a timing diagram corresponding to a pixel driving circuit provided by an embodiment of the present invention, see Figure 1 、 Figure 5 and Figure 7The data writing phase includes phases t1 and t2. During phase t1, the first scan signal Scan1 is at a high level, and the first data writing module 101 writes the pull-down data voltage Vdata1 into the first storage module 103, so that the voltage stored in the first storage module 103 is the pull-down data voltage Vdata1. During phase t2, the second scan signal Scan2 is at a high level, and the second data writing module 102 writes the display data voltage Vdata2 into the second storage module 104, so that the voltage stored in the second storage module 104 is the display data voltage Vdata2. The display data voltage Vdata2 is, for example, greater than the pull-down data voltage Vdata1. It should be noted that the first data writing module 101 and the second data writing module 102 can be turned on when the signal input to the control end is at a high level, or when the signal input to the control end is at a low level. Figure 7 Only the high-level conduction case is shown, but this is not limiting.

[0086] S602. In the light-emitting stage, the driving transistor generates a driving current according to the display data voltage, the leakage current control module controls the leakage current between the first storage module and the second storage module according to the control signal to control the time for the second storage module to discharge to the first storage module, the driving transistor controls the on-time of the driving transistor according to the time for the second storage module to discharge to the first storage module, and the light-emitting module emits light according to the driving current and the on-time.

[0087] Specifically, see Figure 1 、 Figure 5 and Figure 7The light-emitting stage is stage t3. During stage t3, the driving transistor T0 generates a driving current based on the display data voltage Vdata2, and the control signal VG controls the conduction or cutoff of the leakage current control module 105, thereby controlling the magnitude of the leakage current between the first storage module C1 and the second storage module C2. This can control the time when the second storage module 104 discharges to the first storage module 103, thereby controlling the conduction time of the driving transistor T0, thereby controlling the light-emitting duration of the light-emitting module 106, and thus displaying the desired brightness. In addition, by inputting different pull-down data voltages Vdata1, the voltage difference between the first storage module 103 and the second storage module 104 can be controlled, and the time when the second storage module 104 discharges to the first storage module 103 can also be controlled. This can control the conduction time of the driving transistor T0, thereby controlling the light-emitting duration of the light-emitting module 106, and thus displaying different display brightness. Therefore, by controlling the pull-down data voltage Vdata1 of each pixel unit in the display panel and controlling the leakage current between the first storage module 103 and the second storage module 104 of all pixel units through the leakage current control module 105, the light-emitting duration of the light-emitting module 106 in each pixel unit can be controlled, that is, the light-emitting duration of all pixel units can be accurately controlled, so that each pixel unit can display the brightness to be displayed, thereby achieving the effect of improving the display uniformity of the display panel.

[0088] Figure 8 This is a timing diagram corresponding to another pixel driving circuit provided by an embodiment of the present invention. Figure 1 、 Figure 3 、 Figure 5 and Figure 8In the first data writing phase t11, the first scanning signal Scan1 is at a high level, and the first data writing module 101 writes the pull-down data voltage Vdata1 into the first storage module 103; in the initialization phase t12, the first control signal VG11 to the eighth control signal VG18 are all at a high level, and the first leakage current control transistor T11 to the eighth leakage current control transistor T18 are all turned on, and the leakage current is almost zero, achieving the effect of initializing the leakage current and also helping to clear the residual charge of the previous frame display; in the second data writing phase t13, the second scanning signal Scan2 is at a high level, and the second data The writing module 102 writes the display data voltage Vdata2 into the second storage module 104; in the light-emitting stage t14, the EM1 signal is at a high level, the light-emitting control module 107 is turned on, and the light-emitting module 106 can emit light in response to the driving current of the corresponding driving transistor T0. The first control signal VG11 and the second control signal VG12 are at a high level, and the first leakage current control transistor T11 and the second leakage current control transistor T12 are turned on, controlling the time for the second storage module 104 to discharge to the first storage module 103, thereby controlling the on-time of the driving transistor T0, and controlling the light-emitting module 106 to display the brightness to be displayed. Figure 8 FIG. 3 only shows the case where the first leakage current control transistor T11 and the second leakage current control transistor T12 are turned on when the light emitting module 106 emits light, but this is not limiting.

[0089] It should be noted that, in order to facilitate the first switch transistor M1, the second switch transistor M2, the third switch transistor M3, the fourth switch transistor M4, the fifth switch transistor M5, the sixth switch transistor M6, the seventh switch transistor M7 and the eighth switch transistor M8 to control the conduction and cut-off of the corresponding leakage current control transistors, the control signals VM1 to VM8 can all be at a high level, that is, the first switch transistor M1, the second switch transistor M2, the third switch transistor M3, the fourth switch transistor M4, the fifth switch transistor M5, the sixth switch transistor M6, the seventh switch transistor M7 and the eighth switch transistor M8 are all in the on state. There is no need to adjust the timing of the control signals VM1 to VM8. Only the first control signals VG11 to the eighth control signals VG18 need to be adjusted to control the conduction and cut-off of the leakage current control transistors T11 to T18.

[0090] Figure 9 This is a flowchart of a method for debugging a pixel driving circuit according to an embodiment of the present invention. Figure 9 The pixel driving circuit debugging method is used to debug the pixel driving circuit described in any of the above embodiments, and the pixel driving circuit debugging method includes:

[0091] S801. In the data writing phase, the first data writing module writes the reference pull-down data voltage into the first storage module, and the second data writing module writes the display data voltage into the second storage module and into the control terminal of the driving transistor.

[0092] Specifically, see Figure 1 During the data writing phase, the first data writing module 101 writes the reference pull-down data voltage Vdata11 into the first storage module 103, so that the voltage stored in the first storage module 103 is the reference pull-down data voltage Vdata11. The reference pull-down data voltage Vdata11 is, for example, 0V, but can also be other voltage values, which are not limited here. Then, the second data writing module 102 writes the display data voltage Vdata2 into the second storage module 104, so that the voltage stored in the second storage module 104 is the display data voltage Vdata2.

[0093] S802. In the light-emitting stage, the driving transistor generates a driving current according to the display data voltage, and the leakage current control module controls the leakage current between the first end of the first storage module and the first end of the second storage module according to the control signal to control the time for the second storage module to discharge into the first storage module. The driving transistor controls the conduction duration of the driving transistor to be a first duration according to the time for the second storage module to discharge into the first storage module, and the light-emitting module emits light according to the driving current and the first duration.

[0094] Specifically, see Figure 1 In the light-emitting stage, the driving transistor T0 generates a driving current according to the display data voltage Vdata2, and the control signal VG controls the conduction or cutoff of the leakage current control module 105, thereby controlling the magnitude of the leakage current between the first storage module C1 and the second storage module C2, and thus controlling the time for the second storage module 104 to discharge into the first storage module 103. Thus, the conduction time of the driving transistor T0 can be controlled to be the first duration, thereby controlling the light-emitting duration of the light-emitting module 106, thereby displaying the brightness to be displayed.

[0095] S803: When the light-emitting module emits light, detect the display brightness value of the light-emitting module.

[0096] Specifically, see Figure 1 When the light-emitting module 106 emits light, an external optical device can be used to measure the brightness of the entire screen to obtain brightness data at different positions, thereby obtaining the display brightness value of the light-emitting module 106 in each pixel unit and judging whether the display brightness value meets the brightness to be displayed.

[0097] S804. In the data adjustment stage, the reference pull-down data voltage is adjusted to a second pull-down data voltage according to the display brightness value and the brightness value to be displayed, so that the pixel driving circuit drives the light emitting module to display the brightness value to be displayed according to the second pull-down data voltage and the display data voltage.

[0098] Specifically, if the display brightness value of the light-emitting module 106 does not meet the brightness to be displayed, the reference pull-down data voltage is adjusted to a second pull-down data voltage based on the display brightness value and the brightness value to be displayed, thereby adjusting the voltage difference between the first storage module 103 and the second storage module 104, thereby adjusting the discharge time of the second storage module 104, thereby adjusting the conduction time of the driving transistor T0, and thus adjusting the light-emitting duration of the light-emitting module 106, so that the light-emitting module 106 displays the brightness value to be displayed, thereby enabling each light-emitting module 106 to accurately display the brightness to be displayed, which is beneficial for improving the display uniformity of the display panel. When the display brightness value of the light-emitting module 106 does not meet the brightness to be displayed, for example, the reference pull-down data voltage can be increased or decreased to obtain the second pull-down data voltage until the display brightness value of the light-emitting module 106 meets the brightness to be displayed. It should be noted that the brightness value to be displayed and the adjusted second pull-down data voltage can be stored, so that when the display panel is used, the pull-down data voltage corresponding to the brightness to be displayed can be quickly called to accurately display the brightness to be displayed, thereby improving the display effect.

[0099] Note that the above are only preferred embodiments 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 that various obvious changes, readjustments, and substitutions can be made by those skilled in the art 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 the present invention is determined by the scope of the appended claims.

Claims

1. A pixel driving circuit, characterized in that: include: a first data writing module, a second data writing module, a first storage module, a second storage module, a leakage current control module, a driving transistor, and a light emitting module; The control end of the first data writing module is connected to the first scanning signal, the first end of the first data writing module is connected to the pull-down data voltage writing end, the second end of the first data writing module is electrically connected to the first end of the first storage module, the second end of the first storage module is grounded, and the first data writing module is used to write the pull-down data voltage into the first end of the first storage module; The control end of the second data writing module receives the second scanning signal, the first end of the second data writing module is connected to the display data voltage writing end, the second end of the second data writing module is electrically connected to the control end of the driving transistor, the second end of the second data writing module is also electrically connected to the first end of the second storage module, the second end of the second storage module is electrically connected to the first end of the driving transistor, and the second data writing module is used to write the display data voltage into the second storage module and the control end of the driving transistor; The leakage current control module is connected between the first storage module and the second storage module, and is used to control the magnitude of the leakage current between the first storage module and the second storage module when the light-emitting module emits light, so as to control the time for the second storage module to discharge into the first storage module; The driving transistor is used to generate a driving current according to the display data voltage and control its own conduction time according to the time when the second storage module discharges to the first storage module; The light emitting module is configured to emit light according to the driving current and the on-time.

2. The pixel driving circuit according to claim 1, wherein: The control end of the leakage current control module receives a control signal, the first end of the leakage current control module is electrically connected to the first end of the first storage module, and the second end of the leakage current control module is electrically connected to the first end of the second storage module; The first end of the driving transistor is connected to a first power signal, the second end of the driving transistor is electrically connected to the first end of the light emitting module, and the second end of the light emitting module is connected to a second power signal.

3. The pixel driving circuit according to claim 2, wherein: The leakage current control module includes at least one leakage current control transistor; The leakage current control transistor is connected between the first end of the first storage module and the first end of the second storage module, and the control end of the leakage current control transistor is the control end of the leakage current control module.

4. The pixel driving circuit according to claim 3, wherein: The leakage current control module further includes at least one third storage module; A first terminal of the third storage module is electrically connected to the control terminal of the leakage current control transistor, and a second terminal of the third storage module is connected to the first power signal.

5. The pixel driving circuit according to claim 3, wherein: The leakage current control module includes at least two leakage current control transistors; The at least two leakage current control transistors are connected in series between the first end of the first storage module and the first end of the second storage module, and each of the leakage current control transistors has a different channel width-to-length ratio.

6. The pixel driving circuit according to claim 1, wherein: The leakage current control module includes a leakage current control transistor; The leakage current control transistor is connected between the first end of the first storage module and the first end of the second storage module. The control end of the leakage current control transistor is connected to a control signal. The leakage current control transistor is used to adjust its own channel width-to-length ratio according to the control signal when the light-emitting module emits light.

7. The pixel driving circuit according to any one of claims 1 to 6, wherein: The first storage module includes a first capacitor; The first end of the first capacitor is the first end of the first storage module, and the second end of the first capacitor is the second end of the first storage module; And / or, the second storage module includes a second capacitor; The first end of the second capacitor is the first end of the second storage module, and the second end of the second capacitor is the second end of the second storage module.

8. The pixel driving circuit according to any one of claims 2 to 6, wherein: Also included is a lighting control module; The second end of the driving transistor is electrically connected to the first end of the light emitting module through the light emitting control module. The control end of the light emitting control module is connected to an enable signal. The light emitting control module is used to control the light emitting module to emit light according to the enable signal.

9. A driving method for a pixel driving circuit, characterized in that: The driving method is used to drive the pixel driving circuit according to any one of claims 1 to 8, and the driving method includes: In the data writing phase, the first data writing module writes the pull-down data voltage into the first storage module, and the second data writing module writes the display data voltage into the second storage module and into the control terminal of the driving transistor; In the light-emitting stage, the driving transistor generates a driving current according to the display data voltage, the leakage current control module controls the magnitude of the leakage current between the first storage module and the second storage module according to a control signal to control the time for the second storage module to discharge into the first storage module, the driving transistor controls the on-time of the driving transistor according to the time for the second storage module to discharge into the first storage module, and the light-emitting module emits light according to the driving current and the on-time.

10. A method for debugging a pixel driving circuit, characterized in that: The debugging method is used to debug the pixel driving circuit according to any one of claims 1 to 8, and the debugging method includes: In the data writing phase, the first data writing module writes the reference pull-down data voltage into the first storage module, and the second data writing module writes the display data voltage into the second storage module and into the control terminal of the driving transistor; In a light-emitting stage, the driving transistor generates a driving current according to the display data voltage, the leakage current control module controls the magnitude of the leakage current between the first end of the first storage module and the first end of the second storage module according to a control signal, so as to control the time for the second storage module to discharge into the first storage module, the driving transistor controls the on-time of the driving transistor to be a first time length according to the time for the second storage module to discharge into the first storage module, and the light-emitting module emits light according to the driving current and the first time length; When the light-emitting module emits light, detecting a display brightness value of the light-emitting module; In the data adjustment stage, the reference pull-down data voltage is adjusted to a second pull-down data voltage according to the display brightness value and the brightness value to be displayed, so that the pixel driving circuit drives the light-emitting module to display the brightness value to be displayed according to the second pull-down data voltage and the display data voltage.

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