Pixel driving circuit, display panel and display device

Abstract

The embodiments of the present application relate to a pixel driving circuit, a display panel, and a display device, the circuit comprising: a first switching unit, a second switching unit, a third switching unit, a data line, a scan line, an energy storage capacitor, and a light-emitting unit; the control end of the first switching unit is connected to the scan line, the signal input end is connected to the data line, and the signal output end is connected to the control end of the third switching unit; the control end of the second switching unit is connected to the data line, the signal input end is connected to the scan line, and the signal output end is connected to the signal input end of the third switching unit; the signal output end of the third switching unit is connected to the light-emitting unit; one end of the energy storage capacitor is connected to the scan line, and the other end is connected to the control end of the third switching unit. The embodiments of the present application achieve the goal of driving light-emitting diodes to emit light by energy storage capacitors, thereby avoiding the problem of decreasing luminance row by row due to driving multiple rows of light-emitting units by power supply voltage, improving the stability of the light-emitting units, and simplifying the circuit structure.

Description

Technical Field

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

[0002] In existing light-emitting diode display arrays, the scan line corresponding to each row typically drives the row to receive input data signals, and the data line corresponding to each column drives each light-emitting unit in a row to emit light of corresponding intensities. Assuming that the equivalent resistance generated by the power supply line at each scan line is the same, when scanning the first row, the power supply voltage is VDD. When scanning the second row, the power supply voltage changes from VDD of the previous row to VDD', where VDD'=VDD-I*R, where I is the current flowing into the light-emitting unit. As can be seen, as the screen size increases and the number of scan lines increases, the power supply voltage of each row will decrease row by row. This will cause the driving current provided to the light-emitting unit to decrease row by row, which in turn will affect the brightness of the entire screen display, resulting in uneven screen brightness. Summary of the Invention

[0003] In view of this, in order to solve some or all of the above technical problems, the embodiments of the present application provide a pixel driving circuit, a display panel and a display device.

[0004] In a first aspect, an embodiment of the present application provides a pixel driving circuit, which includes: a first switch unit, a second switch unit, a third switch unit, a data line, a scan line, an energy storage capacitor and a light-emitting unit; the control end of the first switch unit is connected to the scan line, the signal input end of the first switch unit is connected to the data line, and the signal output end of the first switch unit is connected to the control end of the third switch unit; the control end of the second switch unit is connected to the data line, the signal input end of the second switch unit is connected to the scan line, and the signal output end of the second switch unit is connected to the signal input end of the third switch unit; the signal output end of the third switch unit is connected to the light-emitting unit; one end of the energy storage capacitor is connected to the scan line, and the other end is connected to the control end of the third switch unit.

[0005] In one possible embodiment, a scanning cycle of the scan line includes a charging phase and a discharging phase. In the charging phase, the voltage difference between the scan line and the data line drives the first switch unit to turn on and drives the second switch unit and the third switch unit to turn off; in the discharging phase, the voltage difference between the scan line and the data line drives the first switch unit to turn off and drives the second switch unit and the third switch unit to turn on.

[0006] In a possible implementation, the turn-on voltages of the first switch unit and the second switch unit are a first voltage, the turn-on voltage of the third switch unit is a second voltage, and the polarities of the first voltage and the second voltage are opposite.

[0007] In a possible implementation, the first switch unit and the second switch unit are N-type field effect transistors, and the third switch unit is a P-type field effect transistor.

[0008] In one possible implementation, the voltage on the scan line is greater than the voltage on the data line, the first switch unit is turned on, and the second and third switch units are turned off; in the discharge phase, the voltage on the scan line is less than the voltage on the data line, the first switch unit is turned off, and the second and third switch units are turned on.

[0009] In a possible implementation, the first switch unit and the second switch unit are P-type field effect transistors, and the third switch unit is an N-type field effect transistor.

[0010] In one possible embodiment, in the charging stage, the voltage on the scan line is lower than the voltage on the data line, the first switch unit is turned on, and the second and third switch units are turned off; in the discharging stage, the voltage on the scan line is higher than the voltage on the data line, the first switch unit is turned off, and the second and third switch units are turned on.

[0011] In a possible implementation, the light-emitting unit is an organic light-emitting diode, an anode of the organic light-emitting diode is connected to the signal output end of the third switch unit, and a cathode of the organic light-emitting diode is connected to the common voltage end.

[0012] In a second aspect, an embodiment of the present application provides a display panel, which includes: a scan driving module, a data driving module, a first preset number of scan lines, a second preset number of data lines and a pixel array; the scan driving module is connected to the first preset number of scan lines, and the data driving module is connected to the second preset number of data lines; each pixel in the pixel array is connected to the corresponding scan line and data line, and each pixel includes a first switching unit, a second switching unit and a third switching unit, an energy storage capacitor and a light-emitting unit, and constitutes the above-mentioned pixel driving circuit together with the corresponding scan line and data line.

[0013] In a third aspect, an embodiment of the present application provides a display device, comprising: a display panel, a panel frame, a power module and a data receiving module as described in the second aspect above; the display panel is installed on the panel frame, the power supply end of the display panel is connected to the power module, and the signal receiving end of the display panel is connected to the data receiving module.

[0014] The pixel driving circuit, display panel, and display device provided by the embodiments of the present application are configured by providing a first switching unit, a second switching unit, and a third switching unit, an energy storage capacitor, and a light-emitting unit in a single pixel. The control terminal of the first switching unit is connected to a scan line, the signal input terminal of the first switching unit is connected to a data line, and the signal output terminal of the first switching unit is connected to the control terminal of the third switching unit. The control terminal of the second switching unit is connected to the data line, the signal input terminal of the second switching unit is connected to the scan line, and the signal output terminal of the second switching unit is connected to the signal input terminal of the third switching unit. The signal output terminal of the third switching unit is connected to the light-emitting unit. One end of the energy storage capacitor is connected to the scan line, and the other end is connected to the control terminal of the third switching unit. The first, second, and third switching units can be controlled to be turned on and off respectively based on the voltage difference between the scan line and the data line. The voltage across the energy storage capacitor is related to the voltage on the scan line and the data line, but not to the power supply voltage. The energy storage capacitor drives the light-emitting diode to emit light, thereby avoiding the problem of decreasing brightness row by row when driving multiple rows of light-emitting units with a uniform power supply voltage, and improving the stability of the light-emitting units. Furthermore, there is no need to provide a separate power supply and wiring, simplifying the circuit structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0018] Figure 1 A schematic structural diagram of a pixel driving circuit provided in an embodiment of the present application;

[0019] Figure 2 A schematic structural diagram of another pixel driving circuit provided in an embodiment of the present application;

[0020] Figure 3 An exemplary schematic diagram of voltage signals and switch states provided in an embodiment of the present application;

[0021] Figure 4A schematic structural diagram of another pixel driving circuit provided in an embodiment of the present application;

[0022] Figure 5 An exemplary schematic diagram of another voltage signal and switch state provided in an embodiment of the present application;

[0023] Figure 6 A schematic structural diagram of a display panel provided in an embodiment of the present application;

[0024] Figure 7 A schematic structural diagram of a display device provided in an embodiment of the present application.

[0025] Reference numerals:

[0026] 100-pixel driving circuit; 101-first switching unit; 102-second switching unit; 103-third switching unit; 104-data line; 105-scan line; 106-energy storage capacitor; light-emitting unit-107; 600-display panel; 601-scanning driving module; 602-data driving module; 603-a first preset number of scan lines; 604-a second preset number of data lines; 605-pixel array; 700-display device; 701-panel frame; 702-power module; 703-data receiving module. DETAILED DESCRIPTION

[0027] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It is apparent that the described embodiments are only a portion of the embodiments of the present application, rather than all of the embodiments. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions, and numerical values ​​described in these embodiments do not limit the scope of the present application.

[0028] Those skilled in the art will understand that the terms "first" and "second" in the embodiments of the present application are only used to distinguish between different steps, devices, modules and other objects, and neither represent any specific technical meaning nor indicate the logical order between them.

[0029] It should also be understood that in this embodiment, “a plurality of” may refer to two or more than two, and “at least one” may refer to one, two or more than two.

[0030] It should also be understood that any component, data or structure mentioned in the embodiments of the present application can generally be understood as one or more, unless explicitly limited or otherwise indicated in the context.

[0031] In addition, the term "and / or" in this application is simply a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0032] It should also be understood that the description of each embodiment in this application focuses on the differences between the embodiments, and the same or similar aspects can be referenced with each other. For the sake of brevity, they will not be described one by one.

[0033] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or uses.

[0034] Technologies, circuits, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, the above-mentioned technologies, circuits, and devices should be considered part of the specification.

[0035] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0036] It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of this application can be combined with each other. To facilitate understanding of the embodiments of this application, the application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0037] The existing scheme of using light-emitting diodes to form a pixel array usually includes two transistors T1 and T2 and a capacitor C. Among them, T1 is the addressing transistor (taking PMOS as an example). When the scan signal (Sel) is at a low level L, T1 is turned on, and the data signal (Data) charges the capacitor C through T1; when sel is at a high level H, T1 is turned off. Since C has no discharge path, the capacitor C will retain the charge until the next time T1 is turned on. The charge stored in the capacitor C is directly connected across the gate and source of the T2 driving transistor (taking PMOS as an example), determining the current flowing through the source and drain of T2, and thus determining the brightness of the light-emitting unit. Taking the OLED screen as an example, the driving current value is , where μ is the active layer mobility, Cox is the capacitance between the gate and the active layer, W is the channel width of the light-emitting diode, L is the channel length of the light-emitting diode, Vdata is the data signal voltage, and VDD is the power supply voltage.

[0038] If R represents the equivalent resistance of the VDD power supply line at the scan line, assuming that the equivalent resistance generated by the power supply line at each scan line is the same. When scanning the first line, the power supply voltage is VDD. When scanning the second line, the power supply voltage changes from VDD of the previous line to VDD', VDD'=VDD-I oled As can be seen, when the screen size is larger and the number of scanning lines is greater, the power supply voltage of each line will decrease line by line, so that the driving current provided to the OLED will decrease line by line, which will in turn affect the brightness of the image displayed on the entire OLED screen.

[0039] In order to solve the problem that the driving current of the light-emitting unit decreases row by row due to the equivalent impedance of the power line, Figure 1 As shown, an embodiment of the present application provides a pixel driving circuit 100, which is generally applied to each pixel in a display panel. The circuit specifically includes: a first switching unit 101, a second switching unit 102, a third switching unit 103, a data line 104 (Data), a scan line 105 (Sel), an energy storage capacitor 106, and a light-emitting unit 107.

[0040] The scan line 105 is used to control the on / off of the light emitting unit 107. The data line 104 is used to output a data signal voltage corresponding to a pixel in the current display image to the light emitting unit 107, which drives the light emitting unit 107 to emit light of corresponding brightness.

[0041] In this embodiment, the control end of the first switch unit 101 is connected to the scan line 105 , the signal input end of the first switch unit 101 is connected to the data line 104 , and the signal output end of the first switch unit 101 is connected to the control end of the third switch unit 103 .

[0042] The control end of the second switch unit 102 is connected to the data line 104 , the signal input end of the second switch unit 102 is connected to the scan line 105 , and the signal output end of the second switch unit 102 is connected to the signal input end of the third switch unit 103 .

[0043] The signal output terminal of the third switch unit 103 is connected to the light emitting unit 107 .

[0044] One end of the energy storage capacitor 106 is connected to the scan line 105 , and the other end is connected to the control end of the third switch unit 103 .

[0045] The first switch unit 101, the second switch unit 102, and the third switch unit 103 can be various types of controlled switch units, such as field-effect transistors (FETs) and triodes. The voltage difference between the outputs of the scan line 105 and the data line 104 can control the on / off state of the first switch unit 101 and the second switch unit 102.

[0046] The energy storage capacitor 106 is used to charge the energy storage capacitor 106 using the voltage difference between the scan line 105 and the data line 104 when the first switch unit 101 is turned on and the second switch unit 102 and the third switch unit 103 are turned off during a scan cycle. Then, when the first switch unit 101 is turned off and the second switch unit 102 is turned on, the voltage across the energy storage capacitor 106 causes the third switch unit 103 to also turn on, thereby discharging the energy storage capacitor 106 and driving the light-emitting unit 107 to emit light.

[0047] Optionally, the light-emitting unit 107 is an organic light-emitting diode, the anode of the organic light-emitting diode is connected to the signal output end of the third switching unit 103, and the cathode of the organic light-emitting diode is connected to the common voltage end, thereby driving the pixels composed of the organic light-emitting diode and improving the display stability of the organic light-emitting diode.

[0048] The pixel driving circuit provided by the embodiments of the present application comprises a first switching unit, a second switching unit, and a third switching unit, an energy storage capacitor, and a light-emitting unit in a single pixel. The control terminal of the first switching unit is connected to a scan line, the signal input terminal of the first switching unit is connected to a data line, and the signal output terminal of the first switching unit is connected to the control terminal of the third switching unit. The control terminal of the second switching unit is connected to the data line, the signal input terminal of the second switching unit is connected to the scan line, and the signal output terminal of the second switching unit is connected to the signal input terminal of the third switching unit. The signal output terminal of the third switching unit is connected to the light-emitting unit. One end of the energy storage capacitor is connected to the scan line, and the other end is connected to the control terminal of the third switching unit. The first, second, and third switching units can be controlled to be turned on and off respectively based on the voltage difference between the scan line and the data line. The voltage across the energy storage capacitor is related to the voltage on the scan line and the data line, but not to the power supply voltage. The energy storage capacitor drives the light-emitting diode to emit light, thereby avoiding the problem of decreasing brightness row by row when driving multiple rows of light-emitting units with a uniform power supply voltage, and improving the stability of the light-emitting units. Furthermore, there is no need to provide a separate power supply and wiring, simplifying the circuit structure.

[0049] In some optional implementations of this embodiment, a scanning cycle of the scan line 105 includes a charging phase and a discharging phase. In the charging phase, the voltage difference between the scan line 105 and the data line 104 drives the first switch unit 101 to turn on and drives the second switch unit 102 and the third switch unit 103 to turn off; in the discharging phase, the voltage difference between the scan line 105 and the data line 104 drives the first switch unit 101 to turn off and drives the second switch unit 102 and the third switch unit 103 to turn on.

[0050] Specifically, during the charging phase, the first switch unit 101 is turned on, the second switch unit 102 is turned off, and the two ends of the energy storage capacitor 106 are connected to the scan line 105 and the data line 104, and the energy storage capacitor 106 is charged. The signal input end of the third switch unit 103 is in a high-impedance state, so the third switch unit 103 is also turned off, and the light-emitting unit 107 has no current input and does not emit light.

[0051] In the discharge phase, the first switch unit 101 is turned off and the second switch unit 102 is turned on. At the same time, the voltage across the energy storage capacitor 106 drives the third switch unit 103 to turn on as well. The energy storage capacitor 106 discharges to the light emitting unit 107, driving the light emitting unit 107 to emit light.

[0052] This embodiment controls the on or off state of the first switch unit, the second switch unit, and the third switch unit by changing the voltage difference between the scan line and the data line within a scan cycle, thereby achieving the light-emitting unit driven by the data line to emit light, avoiding the reduction of the current input to the light-emitting unit due to the equivalent resistance of the power supply.

[0053] In some optional implementations of this embodiment, the on-state voltage of the first switch unit 101 and the second switch unit 102 is a first voltage, the on-state voltage of the third switch unit 103 is a second voltage, and the polarities of the first voltage and the second voltage are opposite.

[0054] The first voltage is a voltage threshold for turning on the first switch unit 101 and the second switch unit 102, and the second voltage is a voltage threshold for turning on the third switch unit 103. For example, the first switch unit 101 and the second switch unit 102 are field-effect transistors of the same type, and their turn-on voltages Vth have the same polarity, for example, Vth>0; the third switch unit 103 is a field-effect transistor of another type, and its turn-on voltage Vth has an opposite polarity to that of the first switch unit 101 and the second switch unit 102, for example, Vth<0.

[0055] During the charging phase, because the control terminals of the first and second switch units 101, 102 are connected to different voltage terminals, the control voltages of the first and second switch units 101, 102 have opposite polarities. For example, if the control voltage Vgs1 of the first switch unit 101 is greater than 0, then the control voltage Vgs2 of the second switch unit 102 is less than 0. Therefore, the first switch unit 101 is turned on and the second switch unit 102 is turned off. The energy storage capacitor 106 is charged, while the signal input terminal of the third switch unit 103 is in a high-impedance state, and the third switch unit 103 is turned off.

[0056] During the discharge phase, the voltage output by the scan line 105 changes, causing the control voltage Vgs1 of the first switch unit 101 to be less than 0, and the control voltage Vgs2 of the second switch unit 102 to be greater than 0. Therefore, the first switch unit 101 is turned off and the second switch unit 102 is turned on. Due to the presence of the energy storage capacitor 106, the voltage difference across the energy storage capacitor 106 causes the control voltage Vgs3 of the third switch unit 103 to be less than 0. Since the turn-on voltage of the third switch unit 103 has the opposite polarity to the turn-on voltages of the other two switch units, the third switch unit 103 is also turned on, the energy storage capacitor 106 is discharged, and the light-emitting unit 107 is driven to emit light.

[0057] In this embodiment, by setting the first switch unit 101 and the second switch unit 102 to have the same polarity of conduction voltage and the third switch unit 103 to have the opposite polarity of conduction voltage, the third switch unit 103 is turned off during the charging phase and turned on during the discharging phase, thereby accurately controlling the on and off of the light-emitting unit 107.

[0058] In some optional implementations of this embodiment, the first switch unit 101 and the second switch unit 102 are N-type field effect transistors, and the third switch unit 103 is a P-type field effect transistor.

[0059] like Figure 2 As shown, T1, T2, and T3 are the first switch unit 101, the second switch unit 102, and the third switch unit 103, respectively. T1's gate (i.e., control terminal) is connected to the scan line 105, its source (i.e., signal input terminal) is connected to the data line 104, and its drain (i.e., signal output terminal) is connected to the gate of T3. T2's gate is connected to the data line 104, its source is connected to the scan line 105, and its drain is connected to the source of T3. The drain of T3 is connected to the light-emitting unit 107. T1 and T2 are both N-type field-effect transistors with a turn-on voltage Vth greater than 0. T3 is a P-type field-effect transistor with a turn-on voltage Vth less than 0.

[0060] This embodiment provides a selection method for the first switch unit 101, the second switch unit 102 and the third switch unit 103, which can accurately control the state of the light-emitting unit 107 during the charging stage and the discharging stage, so that the light-emitting unit 107 can emit light stably.

[0061] In some optional implementations of this embodiment, according to Figure 2 In the circuit shown, in the charging stage, the voltage on the scan line 105 is greater than the voltage on the data line 104, the first switch unit 101 is turned on, and the second switch unit 102 and the third switch unit 103 are turned off; in the discharging stage, the voltage on the scan line 105 is less than the voltage on the data line 104, the first switch unit 101 is turned off, and the second switch unit 102 and the third switch unit 103 are turned on.

[0062] like Figure 3 As shown, it shows the voltage signal transformation on the scan line 105 and the data line 104, as well as the state change of the first switch unit 101, the second switch unit 102, and the third switch unit 103. Figure 3 and Figure 2 The circuit shown in Figure 1 corresponds to this. During the charging phase, the voltage on scan line 105 is 15V, and the voltage on data line 104 is 10V. Therefore, T1's control voltage Vgs1 = 15V - 10V = 5V > Vth, turning it on (a digital "1" indicates on). T2's control voltage Vgs2 = 10V - 15V = -5V < Vth, turning it off (a digital "0" indicates off). T3's source is in a high-impedance state, turning it off, and light-emitting unit 107 does not emit light. The voltage difference across energy storage capacitor 106 is δ = 15V - 10V = 5V.

[0063] During the discharge phase, the voltage on scan line 105 drops to 8V, while the voltage on data line 104 remains at 10V. Since the voltage across energy storage capacitor 106 cannot change suddenly and remains at δ = 5V, the drain voltage of T1 and the gate voltage of T3 are: Vd1 = Vg3 = 8V - δ = 3V. T1's gate voltage Vg1 = 8V, and its source voltage remains the voltage on data line 104, i.e., Vs1 = 10V. Therefore, T1's control voltage Vgs1 = 8V - 10V = -2V < 0, and T1 is turned off. T2's control voltage Vgs2 > Vth, and T2 is turned on. T3's gate voltage Vg3 = 3V, and its source voltage remains the voltage on scan line 105, i.e., Vs3 = 8V. Therefore, T3's control voltage Vgs3 = 3V - 8V = -5V < 0. Since T3 is a P-type field-effect transistor, T3 is turned on. Finally, the energy storage capacitor 106 discharges to the light emitting unit 107 through T3, and the light emitting unit 107 emits light.

[0064] In this embodiment, when the first switch unit 101 and the second switch unit 102 are N-type field effect transistors and the third switch unit 103 is a P-type field effect transistor, the voltage on the scan line 105 in the charging stage is greater than the voltage on the data line 104, and the voltage on the scan line 105 in the discharging stage is less than the voltage on the data line 104. This achieves accurate control of the on and off state of the light-emitting unit 107 within one scanning cycle, thereby improving the stability of the light-emitting unit 107.

[0065] In some optional implementations of this embodiment, the first switch unit 101 and the second switch unit 102 are P-type field effect transistors, and the third switch unit 103 is an N-type field effect transistor.

[0066] like Figure 4 As shown, T1's gate is connected to scan line 105, its source is connected to data line 104, and its drain is connected to T3's gate. T2's gate is connected to data line 104, its source is connected to scan line 105, and its drain is connected to T3's source. T3's drain is connected to light-emitting unit 107. T1 and T2 are both P-type field-effect transistors with a turn-on voltage Vth < 0. T3 is an N-type field-effect transistor with a turn-on voltage Vth > 0.

[0067] This embodiment enriches the circuit implementation method by providing another selection method for the first switch unit 101, the second switch unit 102 and the third switch unit 103. In the charging stage and the discharging stage, the state of the light-emitting unit 107 can be accurately controlled to make the light-emitting unit 107 emit light stably.

[0068] In some optional implementations of this embodiment, in the charging stage, the voltage on the scan line 105 is lower than the voltage on the data line 104, the first switch unit 101 is turned on, and the second switch unit 102 and the third switch unit 103 are turned off; in the discharging stage, the voltage on the scan line 105 is higher than the voltage on the data line 104, the first switch unit 101 is turned off, and the second switch unit 102 and the third switch unit 103 are turned on.

[0069] like Figure 5 As shown, it shows the voltage signal transformation on the scan line 105 and the data line 104, as well as the state change of the first switch unit 101, the second switch unit 102, and the third switch unit 103. Figure 5 and Figure 4The circuit shown in FIG. During the charging phase, the voltage on scan line 105 is 3V, and the voltage on data line 104 is 8V. Therefore, the control voltage Vgs1 of T1 = 3V - 8V = -5V, turning T1 on. The control voltage Vgs2 of T2 = 8V - 3V = 5V, turning T2 off. The source of T3 is in a high-impedance state, turning T3 off as well, and light-emitting unit 107 does not emit light. The voltage difference across energy storage capacitor 106 is δ = 3V - 8V = -5V.

[0070] During the discharge phase, the voltage on scan line 105 rises to 10V, while the voltage on data line 104 remains at 8V. Since the voltage across energy storage capacitor 106 cannot change suddenly and remains at δ = -5V, the drain voltage of T1 and the gate voltage of T3 are: Vd1 = Vg3 = 10V - δ = 15V. T1's gate voltage Vg1 = 10V, and its source voltage remains the voltage on data line 104, i.e., Vs1 = 8V. Therefore, T1's control voltage Vgs1 = 10V - 8V = 2V > 0, turning T1 off. T2's control voltage Vgs2 = 8V - 10V = -2V, turning T2 on. T3's gate voltage Vg3 = 15V, and its source voltage is the voltage on scan line 105, i.e., Vs3 = 10V. Therefore, T3's control voltage Vgs3 = 15V - 10V = 5V. Since T3 is an N-type field-effect transistor, T3 is turned on. Ultimately, the energy storage capacitor 106 discharges to the light-emitting unit 107 through T3, causing the light-emitting unit 107 to emit light.

[0071] In this embodiment, when the first switch unit 101 and the second switch unit 102 are P-type field effect transistors and the third switch unit 103 is an N-type field effect transistor, the voltage on the scan line 105 in the charging stage is lower than the voltage on the data line 104, and the voltage on the scan line 105 in the discharging stage is higher than the voltage on the data line 104. This achieves accurate control of the on and off state of the light-emitting unit 107 within one scanning cycle, thereby improving the stability of the light-emitting unit 107.

[0072] Figure 6 A schematic diagram of the structure of a display panel 600 provided in an embodiment of the present application is shown in FIG. Figure 6 As shown, the display panel specifically includes: a scan driver module 601, a data driver module 602, a first preset number of scan lines 603 (Sel_1-Sel_N), a second preset number of data lines 604 (Data_1-Data_M), and a pixel array 605. Each scan line corresponds to a row of the pixel array, and each data line corresponds to a column of the pixel array.

[0073] The scan driver module 601 is connected to a first preset number of scan lines 603, and the data driver module 602 is connected to a second preset number of data lines 604. The scan driver module 601 is configured to output scan signals to each of the first preset number of scan lines 603 according to an input timing signal. During each scan cycle, the light-emitting unit of each pixel in the pixel array 605 is controlled to turn on and off by charging and discharging the energy storage capacitor within the pixel unit. The data driver module 602 is configured to convert the input image data, specifically the pixel values ​​of each column in the image, into voltage signals, which are then output to each column of pixels via the second preset number of data lines 604.

[0074] Each pixel in the pixel array 605 is connected to the corresponding scan line and data line. Each pixel includes a first switch unit, a second switch unit, a third switch unit, a storage capacitor and a light-emitting unit, and together with the corresponding scan line and data line constitutes the pixel driving circuit described in the above embodiments. Figure 6 The types of the first switch unit, the second switch unit, and the third switch unit shown are only examples, and this embodiment does not limit the types of the first switch unit, the second switch unit, and the third switch unit.

[0075] In addition, the display panel may further include components such as a timing control module and a power management module to provide the pixel array 605 with signals such as scanning timing, image data, and various levels.

[0076] The display panel provided in the embodiment of the present application, by applying the above-mentioned pixel driving circuit, avoids the gradual decrease in brightness of each row of pixels caused by the same column of pixels sharing the same power supply when displaying an image, thereby making the display panel more uniform in brightness when displaying an image and improving the picture display quality.

[0077] Figure 7 A schematic diagram of the structure of a display device 700 provided in an embodiment of the present application is shown in FIG. Figure 7 As shown, the display device includes:

[0078] Display panel 600, panel frame 701, power module 702 and data receiving module 703;

[0079] The display panel 600 may be Figure 6 The display panel 600 is shown. The display panel 600 is mounted on a panel frame 701.

[0080] The power supply end of the display panel 600 is connected to the power module 702 , and the signal receiving end of the display panel 600 is connected to the data receiving module 703 .

[0081] The power module 702 can provide the display panel 600 with the power required for operation. The data receiving module 703 can receive input data. The display panel 600 drives corresponding pixels to display corresponding colors according to the received data.

[0082] In addition, the display device Figure 7 In addition to the parts shown, it may also include a memory for storing data and programs, a processor for running application programs, a data transmission bus, various data interfaces (such as a network interface, a user interface), etc.

[0083] The display device provided in the embodiment of the present application, by applying the above-mentioned display panel, avoids the gradual decrease in brightness of each row of pixels caused by the same column of pixels sharing the same power supply when displaying an image, thereby making the display panel more uniform in brightness when displaying an image and improving the picture display quality.

[0084] Professionals should also be further aware that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different circuits to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0085] The steps of the circuits or algorithms described in conjunction with the embodiments disclosed herein may be implemented using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0086] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "comprise", "include", "contain" and "have" are inclusive and therefore specify the presence of stated features, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the specific order described or illustrated, unless the order of execution is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0087] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A pixel driving circuit, characterized in that: The circuit includes: a first switch unit, a second switch unit, a third switch unit, a data line, a scan line, an energy storage capacitor and a light emitting unit; The control end of the first switch unit is connected to the scan line, the signal input end of the first switch unit is connected to the data line, and the signal output end of the first switch unit is connected to the control end of the third switch unit; The control end of the second switch unit is connected to the data line, the signal input end of the second switch unit is connected to the scan line, and the signal output end of the second switch unit is connected to the signal input end of the third switch unit; The signal output end of the third switch unit is connected to the light emitting unit; One end of the energy storage capacitor is connected to the scan line, and the other end is connected to the control end of the third switch unit; A scanning cycle of the scanning line includes a charging phase and a discharging phase. In the charging phase, the voltage difference between the scanning line and the data line drives the first switching unit to be turned on and drives the second switching unit and the third switching unit to be turned off; in the discharging phase, the voltage difference between the scanning line and the data line drives the first switching unit to be turned off and drives the second switching unit and the third switching unit to be turned on.

2. The circuit according to claim 1, wherein: The conduction voltage of the first switch unit and the second switch unit is a first voltage, the conduction voltage of the third switch unit is a second voltage, and the polarities of the first voltage and the second voltage are opposite.

3. The circuit according to claim 2, characterized in that The first switch unit and the second switch unit are N-type field effect transistors, and the third switch unit is a P-type field effect transistor.

4. The circuit according to claim 3, characterized in that In the charging stage, the voltage on the scan line is greater than the voltage on the data line, the first switch unit is turned on, and the second switch unit and the third switch unit are turned off; in the discharging stage, the voltage on the scan line is less than the voltage on the data line, the first switch unit is turned off, and the second switch unit and the third switch unit are turned on.

5. The circuit according to claim 2, characterized in that The first switch unit and the second switch unit are P-type field effect transistors, and the third switch unit is an N-type field effect transistor.

6. The circuit according to claim 5, characterized in that In the charging stage, the voltage on the scan line is lower than the voltage on the data line, the first switch unit is turned on, and the second switch unit and the third switch unit are turned off; in the discharging stage, the voltage on the scan line is higher than the voltage on the data line, the first switch unit is turned off, and the second switch unit and the third switch unit are turned on.

7. The circuit according to any one of claims 1 to 6, characterized in that: The light emitting unit is an organic light emitting diode, an anode of the organic light emitting diode is connected to the signal output end of the third switch unit, and a cathode of the organic light emitting diode is connected to a common voltage end.

8. A display panel, characterized in that: include: A scan driving module, a data driving module, a first preset number of scan lines, a second preset number of data lines, and a pixel array; The scan driving module is connected to the first preset number of scan lines, and the data driving module is connected to the second preset number of data lines; Each pixel in the pixel array is connected to a corresponding scan line and data line. Each pixel includes a first switch unit, a second switch unit, a third switch unit, an energy storage capacitor and a light-emitting unit, which together with the corresponding scan line and data line constitute the pixel driving circuit according to any one of claims 1 to 7.

9. A display device, characterized in that: include: The display panel, panel frame, power module and data receiving module as claimed in claim 8; The display panel is mounted on the panel frame, a power supply end of the display panel is connected to the power module, and a signal receiving end of the display panel is connected to the data receiving module.

Images