Display device and pixel driving circuit

Abstract

The embodiment of the invention belongs to the display circuit technology, and provides a display device and a pixel driving circuit, the pixel driving circuit comprises a first transistor, a second transistor, a third transistor and a fourth transistor, the control end of the first transistor receives a light-emitting control signal, the first end of the first transistor receives a first voltage signal VGH, and the second end of the second transistor is connected with the control end of the second transistor; one end of the first capacitor receives a reference signal and the other end is connected with the first end of the second transistor; the second end of the second transistor is connected with the first end of the third transistor and the input end of the light-emitting control circuit. The control end of the third transistor receives a light-emitting control signal, and the second end receives a second voltage signal VGL; the output end of the light-emitting control circuit is connected with the LED and is used for controlling the LED according to a signal generated by the second end of the second transistor; the light-emitting control signal and the reference signal are both periodic signals, and the light-emitting control signal has high and low level conversion in each period. The control end of the second transistor receives the first voltage signal VGH, and the first end of the second transistor receives the reference signal, so that the power consumption is effectively reduced.

Description

Technical Field

[0001] The present application relates to display circuit technology, and more specifically, to a display device and a pixel driving circuit. Background Art

[0002] Due to the advantages of Mini-LED and Micro-LED such as high brightness and excellent picture quality, they are widely used in display products.

[0003] In the existing technology, a driving method combining PAM (Pulse Amplitude Modulation) and PWM (Pulse Width Modulation) is usually used for Mini-LED and Micro-LED high grayscale display. The driving process of Mini-LED and Micro-LED can be divided into a reset stage, a data input stage and a comparative light-emitting stage. When this driving method is used for driving, the conduction current in the comparative light-emitting stage is relatively large, resulting in a large driving power consumption. Summary of the invention

[0004] The exemplary embodiments of the present application provide a display device and a pixel driving circuit to solve the problem that when the prior art uses a combination of PAM and PWM to drive Mini-LED and Micro-LED, the conduction current is large during the comparative light-emitting stage, resulting in high driving power consumption.

[0005] In a first aspect, an embodiment of the present application provides a display device, including: a display panel and a pixel driving circuit;

[0006] The display panel includes a plurality of pixels, each pixel including at least one LED;

[0007] The pixel driving circuit includes:

[0008] A first transistor, a control end of which is used to receive a light emitting control signal, a first end of which is used to receive a first voltage signal VGH, and a second end of which is connected to a control end of a second transistor;

[0009] A first capacitor, one end of which is used to receive a reference signal, and the other end of which is connected to the first end of the second transistor;

[0010] The second end of the second transistor is connected to the first end of the third transistor and the input end of the light emitting control circuit respectively;

[0011] The control terminal of the third transistor is used to receive the light emitting control signal, and the second terminal is used to receive the second voltage signal VGL;

[0012] a light emitting control circuit, the output end of which is connected to the LED, and is used to control the LED according to the signal generated by the second end of the second transistor;

[0013] Among them, the light-emitting control signal and the reference signal are both periodic signals. The light-emitting control signal has a high-low level conversion in each period. When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the reference signal is a linearly changing signal.

[0014] In a second aspect, embodiments of the present application provide a display device, a display panel, and a pixel driving circuit;

[0015] The pixel driving circuit is configured as:

[0016] When the light-emitting control signal is converted to a level for controlling the first transistor to be turned on, the light-emitting control signal is received through the first transistor control terminal, the first terminal receives the first voltage signal VGH, the first transistor is turned on, so that the second transistor is turned on, and the light-emitting control circuit controls the LED to emit light according to the signal generated by the second terminal of the second transistor;

[0017] Receiving a linearly varying reference signal through one end of the first capacitor to change the voltage of the first end of the second transistor at the other end of the first capacitor to turn off the second transistor;

[0018] The light emitting control signal is received through the control terminal of the third transistor, and the second terminal receives the second voltage signal VGL, the third transistor is turned on, so that when the second transistor is turned off, the voltage of the second terminal of the second transistor is set to VGL, and the light emitting control circuit controls the LED to stop emitting light according to the current voltage of the second terminal of the second transistor;

[0019] Among them, the light-emitting control signal and the reference signal are both periodic signals. The light-emitting control signal has a high-low level conversion in each period. When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the reference signal is a linearly changing signal.

[0020] In a third aspect, an embodiment of the present application provides a pixel driving circuit, including:

[0021] A first transistor, a control end of which is used to receive a light emitting control signal, a first end of which is used to receive a first voltage signal VGH, and a second end of which is connected to a control end of a second transistor;

[0022] A first capacitor, one end of which is used to receive a reference signal, and the other end of which is connected to the first end of the second transistor;

[0023] The second end of the second transistor is connected to the first end of the third transistor and the input end of the light emitting control circuit respectively;

[0024] The control terminal of the third transistor is used to receive the light emitting control signal, and the second terminal is used to receive the second voltage signal VGL;

[0025] a light emitting control circuit, the output end of which is connected to the LED, and is used to control the LED according to the signal generated by the second end of the second transistor;

[0026] Among them, the light-emitting control signal and the reference signal are both periodic signals. The light-emitting control signal has a high-low level conversion in each period. When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the reference signal is a linearly changing signal.

[0027] The present application provides a display device and a pixel driving circuit. The display device includes a display panel and a pixel driving circuit. The display panel includes a plurality of pixels. The pixel includes at least one LED. The pixel driving circuit is used to control the LED. In the pixel driving circuit, a first transistor receives a light-emitting control signal, a first terminal receives a first voltage signal VGH, the first transistor is turned on, so as to set the voltage of the control terminal of the second transistor to VGH. At this time, the second transistor is turned on, and the light-emitting control circuit can control the LED to turn on according to the signal generated by the current second transistor. As the reference signal changes linearly, the second transistor is turned off. At this time, based on the third transistor, the voltage of the second terminal of the second transistor is set to VGL, and the light-emitting control circuit can control the LED to stop emitting light according to the signal generated by the second terminal of the second transistor. Since the present application connects the second terminal of the first transistor to the control terminal of the second transistor, the control terminal of the second transistor receives the first voltage signal VGH, and the first terminal receives the reference signal, during the LED driving process, compared with the prior art, the present application has a lower current when the first transistor, the second transistor and the third transistor are all turned on, thereby effectively reducing power consumption.

[0028] These and other aspects of the present application will become more apparent from the following description of the embodiment(s). BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the implementation methods in the embodiments of the present application or the related technologies, the following is a brief introduction to the drawings required for use in the embodiments or the related technology descriptions. Obviously, the drawings described below are some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0030] Figure 1 A schematic diagram of a planar structure of a display device provided in an embodiment of the present application;

[0031] Figure 2 A structural diagram of a pixel driving circuit in the prior art;

[0032] Figure 3 A schematic diagram of the structure of a display device provided in an embodiment of the present application;

[0033] Figure 4A schematic diagram of the structure of a pixel driving circuit provided in an embodiment of the present application;

[0034] Figure 5 A timing diagram of related control signal levels corresponding to a P-type thin film transistor provided in an embodiment of the present application;

[0035] Figure 6 A schematic diagram of the structure of a pixel driving circuit corresponding to a P-type thin film transistor in a reset phase provided by an embodiment of the present application;

[0036] Figure 7 A schematic diagram of the structure of a pixel driving circuit corresponding to a P-type thin film transistor in a data input stage provided in an embodiment of the present application;

[0037] Figure 8 A schematic diagram of a pixel driving circuit corresponding to a P-type thin film transistor at an early stage of a comparative light-emitting stage provided by an embodiment of the present application;

[0038] Fig. 9 A schematic structural diagram of a pixel driving circuit corresponding to a P-type thin film transistor in a later light-emitting stage provided by an embodiment of the present application;

[0039] Fig.10 A schematic diagram of a driving circuit corresponding to an N-type thin film transistor provided in an embodiment of the present application;

[0040] Fig.11 A timing diagram of related control signal levels corresponding to an N-type thin film transistor provided in an embodiment of the present application;

[0041] Fig.12 A flow chart of a control method for a pixel driving circuit provided in an embodiment of the present application;

[0042] Fig.13 A schematic diagram of a control device for a pixel driving circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the purpose, implementation mode and advantages of the present application clearer, the exemplary implementation mode of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0044] Based on the exemplary embodiments described in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the claims attached to this application. In addition, although the disclosure in this application is introduced according to one or several exemplary examples, it should be understood that each aspect of the disclosure can also constitute a complete implementation method separately.

[0045] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0046] The terms "first", "second", "third", etc. in the specification and claims of this application and the above drawings are used to distinguish similar or similar objects or entities, and do not necessarily mean to limit a specific order or sequence, unless otherwise indicated. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, for example, they can be implemented according to orders other than those given in the diagrams or descriptions of the embodiments of this application.

[0047] In addition, the terms "include" and "have" and any variations thereof are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to those components expressly listed but may include other components not expressly listed or inherent to such products or devices.

[0048] Figure 1 A schematic diagram of a planar structure of a display device provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the display device may include a pixel array unit 100, a control circuit 200, a data driving circuit 300 and a scan driving circuit 400, wherein the data driving circuit 300 may be a data driver and the scan driving circuit 400 may be a gate driver.

[0049] The pixel array unit 100 may include a plurality of scan lines SL and a plurality of data lines DL disposed on a substrate, and a plurality of pixels P disposed in a plurality of pixel areas defined by crossing portions of the plurality of scan lines SL and the plurality of data lines DL, respectively.

[0050] Each of the plurality of pixels P may include a pixel unit that displays an image based on a scan signal provided by an adjacent scan line SL and a data signal provided by an adjacent data line DL. Specifically, the pixel unit may include at least one thin film transistor and at least one capacitor, and the pixel unit may be a liquid crystal unit that displays an image by driving the liquid crystal according to an electric field based on a data signal, or may be a self-luminous unit that displays an image based on self-luminescence of a data signal. In this case, the self-luminous unit may include a plasma discharge element, a quantum dot light-emitting element, an organic light-emitting element, an inorganic light-emitting element, or a micro-light-emitting diode. It should be noted that the pixel driving circuit provided in the embodiment of the present application belongs to the pixel unit.

[0051] The control circuit 200 may generate pixel data corresponding to each of the plurality of pixels P based on the image signal. The control circuit 200 may generate a data control signal based on the timing synchronization signal to provide the data control signal to the data driving circuit 300. According to an example, the control circuit 200 may generate a start signal and a scanning control signal of a plurality of scanning clock signals based on the timing synchronization signal to provide the scanning control signal to the scanning driving circuit 400. The control circuit 200 may additionally generate a plurality of carry clock signals according to the driving mode of the scanning driving circuit 400 to provide the plurality of carry clock signals to the scanning driving circuit 400.

[0052] The data driving circuit 300 may be connected to a plurality of data lines DL provided in the pixel array unit 100. The data driving circuit 300 may receive pixel data and a data control signal provided from the control circuit 200, and may receive a plurality of reference gamma voltages provided from the power supply circuit. The data driving circuit 300 may convert the pixel data into a pixel-based analog data signal using the data control signal and the plurality of reference gamma voltages, and provide the analog data signal to the corresponding data line DL. The analog data signal is the PWMD signal provided in the embodiment of the present application.

[0053] The scan driving circuit 400 may be connected to a plurality of scan lines SL provided in the pixel array unit 100. Specifically, the scan driving circuit 400 may generate a scan signal according to a predetermined sequence determined based on a scan control signal provided by the control circuit 200, and provide the scan signal to the corresponding scan line SL. The scan signal is the row scan signal SN provided in the embodiment of the present application.

[0054] In some embodiments, the scan driving circuit 400 may be integrated on one edge or two edges of the substrate according to the manufacturing process of the thin film transistor, and then connected to the plurality of scan lines SL in a one-to-one correspondence. For example, the scan driving circuit 400 may be provided in an integrated circuit, may be packaged in a substrate or a flexible circuit film, and may be connected to the plurality of scan lines SL in a one-to-one correspondence.

[0055] Mini-LED and Micro-LED have a higher penetration rate in display products due to their high brightness and excellent image quality. However, the current mainstream TFT (Thin Film Transistor) driving method is to use LTPS (Low Temperature Poly-Silicon) TFT or oxide TFT to drive.

[0056] LTPS TFT has higher electron mobility and better stability, but its cost is higher. In addition, LTPS TFT is limited by the problem of uniformity and cannot be made into large-size single-board, that is, larger than 20 inches.

[0057] Oxide TFT is an amorphous semiconductor device with good uniformity and can be made into large size. However, due to the very low leakage current of the device, it can be used as a low-frequency drive product to achieve ultra-low power consumption. However, due to the poor stability of the device and the low electron mobility, it is not suitable for driving LED chips. It can be used as a switching device, but the cost is also high.

[0058] Traditional a-Si TFT (amorphous silicon thin-film transistor) is a method with a relatively mature industry chain, high yield and low cost. However, due to its low electron mobility, which is usually less than 1, and poor stability, it is generally considered to be unsuitable for driving Micro-LEDs.

[0059] The existing technology can use a driving method combining PAM and PWM for Mini-LED and Micro-LED high grayscale display. The structure diagram of a pixel driving circuit in the existing technology can be referred to Figure 2 As shown, since the driving circuit includes 11 transistors, and in the comparative light-emitting stage, Figure 2 When the transistors T2, T3 and T5 are all turned on, the voltages VGH and VGL form a connection channel. Specifically, the second end of the transistor T2 is connected to the first end of the transistor T3, and the second end of the transistor T3 is connected to the first end of the transistor T5, resulting in a large conduction current and an increase in the power consumption of the driving circuit.

[0060] An embodiment of the present application provides a display device, which includes a pixel driving circuit, so that the control end of the second transistor in the pixel driving circuit receives a PWMD signal and a first voltage signal VGH, and the first end receives a reference signal and a reference voltage signal. When the second transistor is a P-type thin film transistor, that is, the gate of the second transistor receives the PWMD signal and the first voltage signal VGH, and the source receives the reference signal and the reference voltage signal. When the first transistor, the second transistor, and the third transistor are all turned on, the second end of the first transistor is connected to the control end of the second transistor, rather than to the first end of the second transistor, which effectively avoids the formation of a connection channel between VGH and VGL, thereby effectively reducing the power consumption of the driving circuit.

[0061] Figure 3 This is a schematic diagram of the structure of a display device provided in an embodiment of the present application, and the display device includes but is not limited to devices corresponding to Mini-LED and Micro-LED. Figure 3 As shown, the display device includes: a display panel 10 and a pixel driving circuit 20;

[0062] The display panel 10 includes a plurality of pixels, each pixel including at least one LED;

[0063] The pixel driving circuit 20 comprises:

[0064] A first transistor T1, a control end of which is used to receive a light emitting control signal EM, a first end of which is used to receive a first voltage signal VGH, and a second end of which is connected to a control end of a second transistor T2;

[0065] A first capacitor C1, one end of which is used to receive a reference signal Sweep, and the other end of which is connected to a first end of a second transistor T2;

[0066] The second end of the second transistor T2 is connected to the first end of the third transistor T3 and the input end of the light emitting control circuit 201 respectively;

[0067] The control terminal of the third transistor T3 is used to receive the light emitting control signal EM, and the second terminal is used to receive the second voltage signal VGL;

[0068] A light emitting control circuit 201, whose output terminal is connected to the LED, and is used to control the LED according to a signal generated at the second terminal of the second transistor T2;

[0069] The light emitting control signal EM and the reference signal Sweep are both periodic signals. The light emitting control signal EM has a high-low level conversion in each period. When the light emitting control signal EM is converted to a level for controlling the conduction of the first transistor T1, the reference signal Sweep is a linearly changing signal.

[0070] The first transistor T1, the second transistor T2 and the third transistor T3 provided in the embodiment of the present application can be a P-type thin film transistor or an N-type thin film transistor. The transistor can include a gate, a source and a drain. The control end of the above transistor is the gate of the transistor, the first end can be the source, the second end is the drain, or the first end is the drain and the second end is the source. At this time, it is sufficient to satisfy the on and off of the transistor, and the present application does not limit this.

[0071] The first transistor T1 is used to set the voltage of the control terminal of the second transistor T2, namely point A, to VGH when the first transistor T1 is turned on.

[0072] The second transistor T2 is used to provide a voltage at the second end to the light emitting control circuit 201, so that the second light emitting control circuit 201 controls whether the LED emits light according to the voltage at the second end of the second transistor T2. When the second transistor T2 is turned on, the light emitting control circuit 201 can control the LED to emit light according to the current voltage at the second end of the second transistor T2.

[0073] The first capacitor C1 is used to change the voltage at the first end of the second transistor T2, namely, point S, when the reference signal Sweep changes, so as to control the second transistor T2 to be turned off.

[0074] The third transistor T3 is used to set the voltage at the second end of the second transistor T2, i.e., point B, to VGL when the second transistor T2 is turned off. The second end of the second transistor T2 is the input end of the light control circuit 201, so that the light control circuit 201 controls the LED to stop emitting light according to the current voltage VGL at the second end of the second transistor T2.

[0075] The embodiment of the present application provides a display device, including a display panel 10 and a pixel driving circuit 20. In the pixel driving circuit 20, when the light-emitting control signal EM is at a level for controlling the first transistor T1 to be turned on, the first transistor T1 is turned on, and the voltage at the control end of the second transistor T2 is set to VGH, so that the second transistor T2 is turned on. At this time, the light-emitting control circuit 201 can control the LED to emit light according to the signal currently generated by the second transistor T2. With the change of the reference signal Sweep, the second transistor T2 is turned off. At this time, the voltage at the second end of the second transistor T2 is set to VGL by the third transistor T3, and the light-emitting control circuit 201 controls the LED to stop emitting light according to the voltage at the second end of the second transistor T2. The pixel driving circuit 20 of the present application allows the control end of the second transistor T2 to receive the first voltage signal VGH, and the first end to receive the reference signal Sweep. When the first transistor T1, the second transistor T2 and the third transistor T3 are all turned on, the problem of forming a connection channel between VGH and VGL, which leads to a large conduction current, is avoided, thereby effectively reducing the power consumption of the driving circuit.

[0076] Figure 4A schematic diagram of a pixel driving circuit provided in an embodiment of the present application. In one or more embodiments of the present application, in the pixel driving circuit 20, the light emitting control circuit 201 may include the following devices:

[0077] A fourth transistor T4, whose control end is used to receive the light emitting control signal EM, whose first end is used to receive the first voltage signal VGH, and whose second end is connected to the first end of the fifth transistor T5;

[0078] The control end of the fifth transistor T5 is connected to the second end of the second transistor T2, and the second end is connected to the control end of the sixth transistor T6;

[0079] A seventh transistor T7, a control end for receiving the light emitting control signal EM, a first end for receiving the third voltage signal VDD, and a second end connected to the first end of the sixth transistor T6;

[0080] The second end of the sixth transistor T6 is connected to the LED;

[0081] A second capacitor C2, one end of which is used to receive the third voltage signal VDD, and the other end of which is connected to the control end of the sixth transistor T6;

[0082] The third capacitor C3 has one end for receiving the third voltage signal VDD, and the other end connected to the control end of the fifth transistor T5.

[0083] The fourth transistor T4 is used for setting the voltage at the first end of the fifth transistor T5 to VGH when the fourth transistor T4 is turned on.

[0084] The fifth transistor T5 is used to receive the signal generated by the second end of the second transistor T2. When the second transistor T2 is turned on, the fifth transistor T5 is turned off. When the second transistor T2 is turned off, the voltage at the second end of the second transistor T2, i.e., the control end of the fifth transistor T5, is set to VGL through the third transistor T3, and the fifth transistor T5 is turned on. When the fifth transistor T5 is turned on, the voltage at the control end of the sixth transistor T6 can be set to VGH to turn off the sixth transistor T6.

[0085] The seventh transistor T7 is used to set the voltage at the first end of the sixth transistor T6 to VDD when the seventh transistor T7 is turned on.

[0086] The sixth transistor T6 is used to control whether the LED emits light. When the sixth transistor T6 is turned on, the LED emits light. When the sixth transistor T6 is turned off, the current flowing through the LED disappears, and the LED stops emitting light.

[0087] The second capacitor C2 is used to stabilize the voltage at the control end of the sixth transistor T6 , ie, point C. The third capacitor C3 is used to stabilize the voltage at the control end of the fifth transistor T5 , ie, point B, to improve the stability of the pixel driving circuit 20 .

[0088] In summary, the second transistor T2 is turned on to turn off the fifth transistor T5, and further turn on the sixth transistor T6 to control the LED to emit light. Based on the change of the reference signal Sweep, the second transistor T2 is turned off, the fifth transistor T5 is turned on, and further the sixth transistor T6 is turned off, and the LED is controlled to stop emitting light, thereby realizing the grayscale control of the display device.

[0089] In one or more embodiments of the present application, reference is still made to Figure 4 As shown, the pixel driving circuit 20 further includes:

[0090] An eleventh transistor T11, having a control end for receiving a reset signal Reset, a first end for receiving a reference voltage signal Ref, and a second end connected to the first end of the second transistor T2;

[0091] The reset signal Reset is a periodic signal, and each period includes at least a reset stage, a data input stage, and a comparison and light-emitting stage. The reset stage is before the data input stage, and the data input stage is before the comparison and light-emitting stage. In the data input stage and the comparison and light-emitting stage, the level of the reset signal Reset remains consistent and is different from the level in the reset stage.

[0092] The eleventh transistor T11 is used to set the voltage of the first end of the second transistor T2 to Ref when it is turned on, so as to reset the voltage of the first end of the second transistor T2 and clear the residual charge of the first end of the second transistor T2 to prevent the residual charge from affecting the on and off of the second transistor T2 and further affecting the driving of the LED.

[0093] In some embodiments, the pixel driving circuit 20 may further include: an eighth transistor T8, a control end of which is used to receive the row scanning signal SN, a first end of which is used to receive the PWMD signal, and a second end of which is connected to the control end of the second transistor T2;

[0094] a ninth transistor T9, whose control end is used to receive the row scanning signal SN, whose first end is connected to the control end of the second transistor T2, whose second end is used to be connected to the second end of the second transistor T2, and which is used to perform threshold compensation on the second transistor T2;

[0095] A tenth transistor T10, a control end for receiving a row scan signal SN, a first end connected to the control end of the sixth transistor T6, and a second end for receiving a PAMD signal;

[0096] The row scanning signal SN is a periodic signal, and each period includes at least a data input stage and a comparison and light emission stage. In the data input stage and the comparison and light emission stage, the levels of the row scanning signal SN and the light emission control signal EM are different in corresponding stages.

[0097] In some embodiments, the row scan signal SN received at the control end of the eighth transistor T8 is a scan signal transmitted by the scan driving circuit 400 through the scan line SL in the display device, and the PWMD signal received at the first end is an analog data signal transmitted by the data driving circuit 300 through the data line DL in the display device. The eighth transistor T8 is used to set the voltage at the control end of the second transistor T2 to PWMD when it is turned on, so as to turn on the second transistor T2.

[0098] The ninth transistor T9 is used to connect the control terminal and the second terminal of the second transistor T2 to form a diode structure when it is turned on, so as to perform threshold compensation on the second transistor T2 to eliminate the influence of the drift of the threshold voltage of the second transistor T2 and improve the display effect.

[0099] The tenth transistor T10 is used to set the voltage at the control terminal of the sixth transistor T6 to PAMD when the tenth transistor T10 is turned on.

[0100] In some embodiments, the transistors among the first transistor T1, the second transistor T2, the third transistor T3, the fourth transistor T4, the fifth transistor T5, the sixth transistor T6, the seventh transistor T7, the eighth transistor T8, the ninth transistor T9, the tenth transistor T10, and the eleventh transistor T11 are P-type thin film transistors, or N-type thin film transistors.

[0101] In summary, the voltage at the first end of the second transistor T2 can be reset by the eleventh transistor T11 to eliminate the influence of the residual charge at the first end of the second transistor T2 in the previous cycle. The threshold voltage Vth of the second transistor T2 is compensated by the ninth transistor T9 to eliminate the influence of the drift of the threshold voltage Vth of the second transistor T2, which is beneficial to improve the display effect.

[0102] In one or more embodiments of the present application, the cycles of the light emitting control signal EM and the reference signal Sweep at least include a reset phase, a data input phase, and a comparison light emitting phase;

[0103] In the reset phase, the levels of the light emitting control signal EM and the reference signal Sweep are consistent, and are different from the level of the reset signal Reset in the reset phase;

[0104] In the data input stage, the levels of the light emitting control signal EM and the reference signal Sweep are consistent, and are consistent with the level of the reset signal Reset in the data input stage;

[0105] In the comparison light-emitting stage, the light-emitting control signal EM is at a level for controlling the first transistor T1 to be turned on, and is different from the level in the data input stage, and the reference signal Sweep changes linearly;

[0106] The row scanning signal SN also includes a reset phase in each cycle. In the reset phase, the row scanning signal SN has a level consistent with that corresponding to the comparison light-emitting phase.

[0107] The above-mentioned transistor can be a P-type thin film transistor or an N-type thin film transistor. Since the conduction of the transistor needs to meet certain conditions, and the conduction condition is related to the type of transistor. In one implementation scenario, the conduction condition of the P-type transistor is Vgs < 0, where Vgs represents the voltage difference between the gate and the source of the transistor, that is, the gate voltage is less than the source voltage. In another implementation scenario, the conduction condition of the N-type transistor is Vgs > 0, that is, the gate voltage is greater than the source voltage.

[0108] If the first transistor T1 to the eleventh transistor T11 are all P-type thin film transistors, the timing diagram of the relevant control signal levels corresponding to the P-type thin film transistors can refer to Figure 5 shown.

[0109] Taking a P-type thin film transistor as an example, a specific embodiment is provided below to describe in detail the specific driving processes of the reset phase, the data input phase and the comparative light emitting phase during the control process of the pixel driving circuit 20, as follows:

[0110] Reset phase:

[0111] Figure 6 A schematic diagram of the structure of a pixel driving circuit corresponding to a P-type thin film transistor in a reset phase provided by an embodiment of the present application. Figure 5 and Figure 6 It can be seen that in the reset stage, the reset signal Reset is a low level signal. The control end of the eleventh transistor T11 receives the reset signal Reset, and the first end receives the reference voltage signal Ref, Reset<Ref, the eleventh transistor T11 is turned on, the voltage at point S is set to Ref, and the charge is cleared. Among them, point S is both the second end of the eleventh transistor T11 and the first end of the second transistor T2.

[0112] In the reset stage, since the row scanning signal SN is at a high level, for the eighth transistor T8, SN>PWMD, causing the eighth transistor T8 to be turned off. Since the eighth transistor T8 is turned off, there is no voltage at the first end of the ninth transistor T9, and the ninth transistor T9 is turned off. For the tenth transistor T10, SN>PAMD, and the tenth transistor T10 is turned off.

[0113] In the reset stage, since the light emitting control signal EM is at a high level, for the first transistor T1, EM>VGH, the first transistor T1 is turned off. For the third transistor T3, since EM>VGL, the third transistor T3 is turned off. For the fourth transistor T4, EM>VGH, the fourth transistor T4 is turned off. For the seventh transistor T7, EM>VDD, the seventh transistor T7 is turned off.

[0114] Since the first transistor T1 is turned off and the eighth transistor T8 is turned off, there is no voltage at the control end of the second transistor T2, which causes the second transistor T2 to be turned off. Since the fourth transistor T4 is turned off, there is no voltage at the first end of the fifth transistor T5, which causes the fifth transistor T5 to be turned off. Since the seventh transistor T7 is turned off, there is no voltage at the first end of the sixth transistor T6, which causes the sixth transistor T6 to be turned off, and the LED does not emit light.

[0115] In the reset stage, since the reference signal Sweep is at a high level, based on the basic characteristics of the capacitor, the circuit where the first capacitor C1 is located can be regarded as an open circuit.

[0116] Data entry phase:

[0117] Figure 7 A schematic diagram of a pixel driving circuit corresponding to a P-type thin film transistor in a data input stage provided by an embodiment of the present application. Figure 5 and Figure 7 It can be seen that in the data input stage, the reset signal Reset is at a high level, and since Reset>Ref, the eleventh transistor T11 is turned off.

[0118] In the data input stage, since the light-emitting control signal EM is still at a high level, since EM>VGH, the first transistor T1 is turned off. Since EM>VGL, the third transistor T3 is turned off. Since EM>VGH, the fourth transistor T4 is turned off, and then the fifth transistor T5 is turned off. Since EM>VDD, the seventh transistor T7 is turned off, which in turn causes the sixth transistor T6 to be turned off, and the LED does not emit light. Since the reference signal Sweep is at a high level, based on the basic characteristics of the capacitor, the line where the first capacitor C1 is located can be regarded as an open circuit.

[0119] In the data input stage, the control terminal of the eighth transistor T8 receives the row scan signal SN, the first terminal receives the PWMD signal, the eighth transistor T8 is turned on, so that the voltage of the control terminal of the second transistor T2 is set to PWMD, and the second transistor T2 is turned on;

[0120] The ninth transistor T9 receives the row scanning signal SN through the control terminal thereof, and the ninth transistor T9 is turned on to perform threshold compensation on the second transistor T2;

[0121] The control terminal of the tenth transistor T10 receives the row scan signal SN, and the first terminal receives the PAMD signal, so as to set the voltage of the control terminal of the sixth transistor T6 to PAMD;

[0122] The row scanning signal SN is a periodic signal, and each period includes at least a data input stage and a comparison and light emission stage. In the data input stage and the comparison and light emission stage, the levels of the row scanning signal SN and the light emission control signal EM are different in corresponding stages.

[0123] Based on the principle of P-type thin film transistors, in the data input stage, the row scanning signal SN is controlled to be a low level.

[0124] For the eighth transistor T8, SN<PWMD, so that the eighth transistor T8 is turned on, and the voltage at point A is set to PWMD. The control end of the ninth transistor T9 also receives the row scan signal SN, and the first end is PWMD. SN<PWMD, so that the ninth transistor T9 is turned on. At the same time, since the voltage at point S is Ref, PWMD<Ref, the second transistor T2 is turned on. Among them, point A can represent the second end of the first transistor T1, the second end of the eighth transistor T8, the control end of the second transistor T2, and the first end of the ninth transistor T9. The PWMD signal is a voltage value that changes according to the brightness of the LED.

[0125] Since the ninth transistor T9 is turned on, the control end of the second transistor T2 is connected to the second end, that is, the AB point is connected to form a diode structure, so the voltage at point B becomes PWMD, and the voltage at point S, that is, the first end of the second transistor T2, becomes PWMD+Vth, so as to perform threshold compensation on the second transistor T2. Wherein, Vth is the threshold voltage of the second transistor T2. Point B can represent the second end of the second transistor T2, the first end of the third transistor T3, and the control end of the fifth transistor T5.

[0126] After the voltage at point S becomes PWMD+Vth, since the voltage at point A is still PWMD, the voltage at point A is less than the voltage at point S, causing the second transistor T2 to be turned off, and at this time the threshold voltage Vth of the second transistor T2 can be stored on the first capacitor C1. PWMD+Vth is the initial voltage value corresponding to point S after the data input stage mentioned in the above embodiment.

[0127] The control terminal of the tenth transistor T10 also receives the row scan signal SN. Since the row scan signal SN is at a low level at this time, the second terminal receives the PAMD signal. SN<PAMD, the tenth transistor T10 is turned on, causing the voltage at point C to become PAMD. Point C is the control terminal of the sixth transistor T6 or the second terminal of the fifth transistor T5.

[0128] Compare the luminous phases:

[0129] The light emitting control signal EM is used to control the level of the first transistor T1 to be turned on, corresponding to the comparative light emitting stage. The comparative light emitting stage can be divided into two stages, the early comparative light emitting stage and the late comparative light emitting stage, according to the on-off of the second transistor T2.

[0130] Figure 8 A schematic diagram of the structure of a pixel driving circuit corresponding to a P-type thin film transistor in an early stage of a comparative light-emitting phase provided by an embodiment of the present application. Figure 5 and Figure 8 As shown, at the beginning of the comparison light-emitting stage, the reset signal Reset is still at a high level. Since Reset>Ref, the eleventh transistor T11 is still in the off state.

[0131] At the beginning of the comparative light-emitting stage, the row scanning signal SN is at a high level. Since SN>PWMD, the eighth transistor T8 is turned off. Since the eighth transistor T8 is turned off, there is no voltage at the first end of the ninth transistor T9, and the ninth transistor T9 is turned off. For the tenth transistor T10, SN>PAMD, and the tenth transistor T10 is turned off.

[0132] In the early stage of the comparative light-emitting phase, based on the conduction principle of the P-type thin film transistor, the level of controlling the conduction of the first transistor T1 is low, so the light-emitting control signal EM is low, and the reference signal Sweep decreases linearly.

[0133] The control terminal of the third transistor T3 receives the light-emitting control signal EM, and the second terminal receives the second voltage signal VGL, EM<VGL, causing the third transistor T3 to be turned on. The control terminal of the first transistor T1 receives the light-emitting control signal EM, and the first terminal receives the first voltage signal VGH, EM<VGH, so the first transistor T1 is turned on, and the voltage at point A can be set to VGH through the first transistor T1. At this time, the initial voltage at point S is PWMD+Vth, and since VGH<PWMD+Vth, the second transistor T2 is in the on state. At this time, the voltage difference between the control terminal and the first terminal of the second transistor T2, that is, the voltage difference between the gate and the source, Vgs=VGH-PWMD-Vth, so the internal compensation of the second transistor T2 has been completed.

[0134] At the beginning of the comparative light-emitting stage, due to the linear decrease of the reference signal Sweep, the voltage at point S also gradually decreases based on the effect of the first capacitor C1. When S>VGH+Vth, the second transistor T2 remains on. At this time, point B is set to a high level through the second transistor T2, and this level is the equilibrium potential of the second transistor T2, the first capacitor C1 and the reference signal Sweep.

[0135] The control terminal of the fourth transistor T4 also receives the light emitting control signal EM. Since the light emitting control signal EM is at a low level, EM<VGH, the fourth transistor T4 is turned on, and the voltage at the first terminal of the fifth transistor T5 is set to VGH. Since the voltage VB at point B, i.e., the control terminal of the fifth transistor T5, is at a high level, VB>VGH, the fifth transistor T5 is turned off.

[0136] The control end of the seventh transistor T7 also receives the light emitting control signal EM, and the first end receives the third voltage signal VDD. Since the light emitting control signal EM is at a low level at this time, EM<VDD, the seventh transistor T7 is also turned on, and the voltage of the first end of the sixth transistor T6 is set to VDD.

[0137] At this time, the voltage at point C, i.e., the control terminal of the sixth transistor T6, is PAMD, which is a low potential, indicating the voltage value when the LED emits the highest brightness. Since PAMD < VDD, the sixth transistor T6 is turned on. Since the second terminal of the sixth transistor T6 is connected to the anode of the LED, the cathode of the LED receives the light-emitting control signal EM, and at this time, there is a voltage difference between the voltages at both ends of the LED, and the light-emitting condition of the LED is met, so after the sixth transistor T6 is turned on, the LED starts to emit light.

[0138] Fig. 9 A schematic diagram of a pixel driving circuit corresponding to a P-type thin film transistor in a later light-emitting stage provided by an embodiment of the present application. Figure 5 and Fig. 9 As shown, in the later stage of the comparative light-emitting phase, the reset signal Reset is still at a high level, and since Reset>Ref, the eleventh transistor T11 is still in the off state.

[0139] In the later stage of the comparative light-emitting phase, the row scanning signal SN is at a high level. Since SN>PWMD, the eighth transistor T8 is turned off. Since the eighth transistor T8 is turned off, there is no voltage at the first end of the ninth transistor T9, and the ninth transistor T9 is turned off. For the tenth transistor T10, SN>PAMD, and the tenth transistor T10 is turned off.

[0140] In the later stage of the comparative light-emitting phase, the light-emitting control signal EM still maintains a low level. Since EM<VGH, the first transistor T1 is still in the on state. Similarly, since EM<VGL, the third transistor T3 is still in the on state. Since EM<VGH, the fourth transistor T4 is still in the on state. Since EM<VDD, the seventh transistor T7 is also still in the on state.

[0141] As the reference signal Sweep continues to decrease, the voltage at point S will continue to decrease. When S<VGH+Vth, the second transistor T2 is turned off. At this time, the voltage at point B is set to VGL through the third transistor T3, and VHL is a low-level signal. Since VGL<VGH, the fifth transistor T5 is turned on. Since the fifth transistor T5 is turned on, the voltage at point C is set to VGH, VGH>VDD, causing the sixth transistor T6 to be turned off, so the current flowing through the LED disappears, the LED stops emitting light, and grayscale control is achieved.

[0142] In the embodiment of the present application, the second end of the third transistor T3 is used to receive the second voltage signal VGL for illustration. In this case, it is required that at the beginning of the light-emitting stage, the second transistor T2 is in the on state, and the first end of the second transistor T2 needs to input a high voltage to ensure the high voltage at point B. At this time, the initial voltage value of the first end of the second transistor T2 is PWMD+Vth, and PWMD+Vth is required to be a high potential. After the voltage at point A changes from PWMD to VGH, the second transistor T2 is required to be turned on all the time, and the voltage at point S cannot change suddenly, and VGH<PWMD+Vth is required, that is, the voltage value of VGH is less than the voltage value of PWMD. At this time, the reference signal Sweep is required to drop to reduce the voltage difference of Vgs, gradually turning off the second transistor T2, so as to realize the conversion from high potential to low potential at point B based on the third transistor T3, so the second end of the third transistor T3 receives the second voltage signal VGL, which can realize the driving of the LED.

[0143] In another implementation scenario, if the second end of the third transistor T3 is used to receive the first voltage signal VGH, the second transistor T2 needs to be turned off first and then turned on to input a low level to pull down the voltage at point B. The condition that the second transistor T2 needs to meet for turning on is: PWMD+△Sweep>VGH, where △Sweep is the voltage of the reference signal Sweep change. For the requirement that the second transistor T2 is turned off first and then turned on, VGH can be made to be a larger voltage value to meet the requirement that the second transistor T2 is turned off at the beginning of the comparative light-emitting stage, and then the △Sweep voltage is required to increase to meet the requirement that the second transistor T2 is turned on in the later period of the comparative light-emitting stage. However, due to the increase in the reference signal Sweep voltage, the voltage at point S will increase, which is inconsistent with the final low voltage requirement at point B. Therefore, the setting that the second end of the third transistor T3 receives the first voltage signal VGH is unreasonable.

[0144] It should be noted that the above embodiments are described in detail by taking the first transistor T1 to the eleventh transistor T11 as P-type thin film transistors as an example.

[0145] In another implementation scenario, if the above transistors included in the pixel driving circuit 20 are all N-type thin film transistors, the levels of the reset signal Reset, the row scanning signal SN, the light emitting control signal EM and the reference signal Sweep at different stages are different from the current Figure 5 The voltage levels of the P-type thin film transistors given in the corresponding stages are different. For the N-type thin film transistor, the voltage difference between the gate and the source Vgs < 0 is in the off state, and Vgs > 0 is in the on state. Based on the principle of the N-type thin film transistor, the structural schematic diagram of the driving circuit corresponding to the N-type thin film transistor can be referred to Fig.10 As shown, the timing diagram of the relevant control signal level corresponding to the N-type thin film transistor can be referred to Fig.11 The driving principle of the pixel driving circuit corresponding to the N-type thin film transistor can refer to the driving principle of the pixel driving circuit corresponding to the above-mentioned P-type thin film transistor, and this application will not repeat it here.

[0146] It should also be noted that the first voltage signal VGH, the second voltage signal VGL, the third voltage signal VDD and the reference voltage signal Ref can be provided by a DC power supply, and the voltage magnitudes thereof can satisfy the on and off conditions of the corresponding transistors.

[0147] In summary, the pixel driving circuit 20 swaps the signals received by the control end and the first end of the second transistor T2, that is, the control end of the second transistor T2 receives the PWMD signal, and the first end receives the reference voltage signal Ref and the reference signal Sweep. When the first transistor T1, the second transistor T2, and the third transistor T3 are all turned on, there is no need to increase the pixel driving circuit 20 signal, thereby avoiding the problem of a connection channel being formed between VGH and VGL in the comparative light-emitting stage of the pixel driving circuit in the prior art, resulting in a large conduction current, thereby effectively reducing the power consumption of the pixel driving circuit 20.

[0148] The embodiment of the present application provides a display device, including a display panel 10 and a pixel driving circuit 20;

[0149] The pixel driving circuit 20 is configured as follows:

[0150] When the light emitting control signal EM is converted to a level for controlling the first transistor T1 to be turned on, the light emitting control signal EM is received by the control terminal of the first transistor T1, the first terminal receives the first voltage signal VGH, the first transistor T1 is turned on, so that the second transistor T2 is turned on, and the light emitting control circuit 201 controls the LED to emit light according to the signal generated by the second terminal of the second transistor T2;

[0151] A linearly varying reference signal Sweep is received through one end of the first capacitor C1, so that the voltage of the first end of the second transistor T2 at the other end of the first capacitor C1 changes, so that the second transistor T2 is turned off;

[0152] The control terminal of the third transistor T3 receives the light control signal EM, and the second terminal receives the second voltage signal VGL. The third transistor T3 is turned on, so that when the second transistor T2 is turned off, the voltage at the second terminal of the second transistor T2 is set to VGL, and the light control circuit 201 controls the LED to stop emitting light according to the current voltage at the second terminal of the second transistor T2;

[0153] The light emitting control signal EM and the reference signal Sweep are both periodic signals. The light emitting control signal EM has a high-low level conversion in each period. When the light emitting control signal EM is converted to a level for controlling the conduction of the first transistor T1, the reference signal Sweep is a linearly changing signal.

[0154] In some embodiments, the light emitting control circuit 201 is configured as follows:

[0155] When the light emitting control signal EM is converted to a level for controlling the first transistor T1 to be turned on, the light emitting control signal EM is received by the control terminal of the fourth transistor T4, the first terminal receives the first voltage signal VGH, and the fourth transistor T4 is turned on to set the voltage of the first terminal of the fifth transistor T5 to VGH;

[0156] When the second transistor T2 is turned on, the control terminal of the fifth transistor T5 receives the signal generated by the second terminal, and the fifth transistor T5 is turned off;

[0157] The control terminal of the seventh transistor T7 receives the light-emitting control signal EM, and the first terminal receives the third voltage signal VDD. The seventh transistor T7 is turned on to set the voltage of the first terminal of the sixth transistor T6 to VDD. The sixth transistor T6 is turned on, and the LED emits light;

[0158] The control terminal of the fifth transistor T5 receives the second voltage signal VGL transmitted by the third transistor T3 when the second transistor T2 is turned off, and the fifth transistor T5 is turned on to turn off the sixth transistor T6, and the LED stops emitting light.

[0159] The specific process of the pixel driving circuit 20 and the light emitting control circuit 201 may refer to the above embodiments, and the principle of the specific driving process may refer to the above embodiments, which will not be repeated in this application.

[0160] The embodiment of the present application provides a pixel driving circuit 20, including:

[0161] A first transistor T1, whose control end is used to receive a light emitting control signal EM, whose first end is used to receive a first voltage signal VGH, and whose second end is connected to a control end of a second transistor T2;

[0162] A first capacitor C1, one end of which is used to receive a reference signal Sweep, and the other end of which is connected to a first end of a second transistor T2;

[0163] The second end of the second transistor T2 is connected to the first end of the third transistor T3 and the input end of the light emitting control circuit 201 respectively;

[0164] The control terminal of the third transistor T3 is used to receive the light emitting control signal EM, and the second terminal is used to receive the second voltage signal VGL;

[0165] A light emitting control circuit 201, whose output terminal is connected to the LED, and is used to control the LED according to a signal generated at the second terminal of the second transistor T2;

[0166] The light emitting control signal EM and the reference signal Sweep are both periodic signals. The light emitting control signal EM has a high-low level conversion in each period. When the light emitting control signal EM is converted to a level for controlling the conduction of the first transistor T1, the reference signal Sweep is a linearly changing signal.

[0167] The structure of the pixel driving circuit can be referred to Figure 3 The structure of the pixel driving circuit 20 shown in FIG. 1 and its specific driving process may refer to other embodiments, which will not be described in detail in this application.

[0168] An embodiment of the present application provides a display device, including a control module, a display panel, and a pixel driving circuit provided in the above embodiment, wherein the control module is used to output a light emitting control signal EM and a reference signal Sweep to control the pixel driving circuit. The specific control process can be referred to other embodiments and will not be repeated here.

[0169] In some embodiments, the display device may be a Mini-LED or Micro-LED display device, and each liquid crystal pixel is driven by a thin film transistor integrated therebehind.

[0170] Fig.12 This is a flow chart of a control method for a pixel driving circuit provided in an embodiment of the present application. The method of this embodiment can be executed by a control module and can be implemented by hardware, software, or a combination of hardware and software. Fig.12 As shown, the method includes:

[0171] S1201: In each cycle, the light emitting control signal is controlled to switch between high and low levels.

[0172] In some embodiments, each cycle includes at least a data input stage and a comparison and light emission stage. When switching from the data input stage to the comparison and light emission stage, the light emission control signal EM may be controlled to perform a high-low level conversion.

[0173] S1202: When the light emitting control signal is converted to a level for controlling the first transistor to be turned on, the control reference signal changes linearly.

[0174] In some embodiments, if the transistors included in the pixel driving circuit are all P-type thin film transistors, combined with Figure 6 As shown, based on the characteristics of the P-type thin film transistor, that is, the gate-source voltage difference Vgs<0, the P-type thin film transistor is turned on, and it can be known that the level for controlling the first transistor T1 to be turned on is a low level, so the light emitting control signal EM can be controlled to be a high level in the data input stage, and the reference signal Sweep can be controlled to be a high level at this time. In addition to the light emitting control signal EM and the reference signal Sweep, the row scanning signal SN can also be controlled to be a low level, and the reset signal Reset can be controlled to be a high level.

[0175] Entering the comparison light-emitting stage, the light-emitting control signal EM is controlled to be converted from a high level to a low level, and the reference signal Sweep can be controlled to be linearly reduced. In addition to the light-emitting control signal EM and the reference signal Sweep, the reset signal Reset and the row scanning signal SN can also be controlled to be high levels.

[0176] In some embodiments, a reset phase may be included before the data input phase. In the reset phase, the reset signal Reset may be controlled to be at a low level, and the row scanning signal SN, the light emitting control signal EM and the reference signal Sweep may all be at high levels.

[0177] In some embodiments, if the transistors included in the pixel driving circuit are all N-type thin film transistors, the levels of the above signals in different stages are different from the levels of the P-type thin film transistors in the corresponding stages. Specifically, based on the characteristics of the N-type thin film transistor, that is, the gate-source voltage difference Vgs>0, the N-type thin film transistor is turned on, and it can be known that the level for controlling the first transistor T1 to be turned on is a high level. Therefore, in the data input stage, the light emitting control signal EM and the reference signal Sweep can be controlled to be low levels. In addition to the light emitting control signal EM and the reference signal Sweep, the row scanning signal SN can also be controlled to be a high level, and the reset signal Reset can be controlled to be a low level.

[0178] Entering the comparison light-emitting stage, the light-emitting control signal EM is controlled to switch from a low level to a high level, and the reference signal Sweep can be controlled to increase linearly. In addition to the light-emitting control signal EM and the reference signal Sweep, the reset signal Reset and the row scanning signal SN can also be controlled to be low levels.

[0179] In the reset stage, the reset signal Reset may be controlled to be at a high level, and the row scanning signal SN, the light emitting control signal EM and the reference signal Sweep may all be at a low level.

[0180] The embodiment of the present application provides a control method for a pixel driving circuit, in which a light emitting control signal EM is controlled to convert between high and low levels in each cycle, and when the light emitting control signal EM is converted to a level for controlling the conduction of the first transistor T1, the reference signal Sweep is controlled to change linearly. By controlling the light emitting control signal EM and the reference signal Sweep, the conduction and shutoff of the corresponding transistors in the pixel driving circuit are controlled to realize the driving of the LED.

[0181] Fig.13 Schematic diagram of a control device for a pixel driving circuit provided in an embodiment of the present application. Fig.13 As shown, an embodiment of the present application provides a control device 1300 for a pixel driving circuit, including a processor 1301 and a memory 1302 , wherein the memory 1302 stores codes, and the processor 1301 runs the codes stored in the memory 1302 to execute the above method.

[0182] The specific implementation process of the processor 1301 can be found in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be repeated here.

[0183] In the above Fig.13 In the illustrated embodiment, it should be understood that the processor 1301 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the invention may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0184] The memory 1302 may include a high-speed RAM memory, and may also include a non-volatile storage NVM, such as at least one disk storage.

[0185] The processor 1301 and the memory 1302 may be connected via a bus 1303. The bus 1303 may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. The bus 1303 may be an address bus, a data bus, a control bus, etc. For ease of representation, the bus 1303 in the drawings of the present application is not limited to only one bus or one type of bus.

[0186] An embodiment of the present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement a method as described in any of the above method embodiments.

[0187] An embodiment of the present application also provides a computer program product, including a computer program, which can implement the method of any of the above method embodiments when executed by a processor.

[0188] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0189] For ease of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are intended to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A display device, It is characterized in that include: Display panel and pixel driving circuit; The display panel includes a plurality of pixels, each pixel including at least one LED; The pixel driving circuit comprises: A first transistor, a control end of which is used to receive a light emitting control signal, a first end of which is used to receive a first voltage signal VGH, and a second end of which is connected to a control end of a second transistor; a first capacitor, one end of which is used to receive a reference signal, and the other end of which is connected to the first end of the second transistor; The second end of the second transistor is connected to the first end of the third transistor and the input end of the light emitting control circuit respectively; The control terminal of the third transistor is used to receive the light emitting control signal, and the second terminal is used to receive the second voltage signal VGL; The light emitting control circuit has an output end connected to the LED and is used to control the LED according to the signal generated by the second end of the second transistor; Among them, the light-emitting control signal and the reference signal are both periodic signals, and the light-emitting control signal has a high-low level transition in each period. When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the reference signal is a linearly changing signal.

2. The display device according to claim 1, It is characterized in that The light emitting control circuit comprises: A fourth transistor, whose control end is used to receive the light emitting control signal, whose first end is used to receive the first voltage signal VGH, and whose second end is connected to the first end of the fifth transistor; The control terminal of the fifth transistor is connected to the second terminal of the second transistor, and the second terminal is connected to the control terminal of the sixth transistor; A seventh transistor, whose control end is used to receive the light emitting control signal, whose first end is used to receive the third voltage signal VDD, and whose second end is connected to the first end of the sixth transistor; The second end of the sixth transistor is connected to the LED; A second capacitor, one end of which is used to receive the third voltage signal VDD, and the other end of which is connected to the control end of the sixth transistor; The third capacitor has one end for receiving the third voltage signal VDD and the other end connected to the control end of the fifth transistor.

3. The display device according to claim 2, It is characterized in that Also includes: an eighth transistor, whose control end is used to receive a row scanning signal, whose first end is used to receive a PWMD signal, and whose second end is connected to the control end of the second transistor; a ninth transistor, whose control end is used to receive the row scanning signal, whose first end is connected to the control end of the second transistor, whose second end is used to be connected to the second end of the second transistor, and which is used to perform threshold compensation on the second transistor; a tenth transistor, whose control end is used to receive the row scanning signal, whose first end is connected to the control end of the sixth transistor, and whose second end is used to receive the PAMD signal; The row scanning signal is a periodic signal, and each period includes at least a data input stage and a comparison and light emission stage; in the data input stage and the comparison and light emission stage, the level of the row scanning signal and the light emission control signal in the corresponding stage are different.

4. The display device according to claim 3, It is characterized in that Also includes: an eleventh transistor, having a control end for receiving a reset signal, a first end for receiving a reference voltage signal, and a second end connected to the first end of the second transistor; The reset signal is a periodic signal, and each period at least includes a reset stage, a data input stage and a comparison light-emitting stage. The reset stage is before the data input stage, and the data input stage is before the comparison light-emitting stage. In the data input stage and the comparison light-emitting stage, the level of the reset signal remains consistent and is different from the level in the reset stage.

5. The display device according to claim 4, It is characterized in that The cycles of the light emitting control signal and the reference signal at least include a reset phase, a data input phase and a comparison light emitting phase; Wherein, in the reset stage, the level of the light emitting control signal is consistent with the level of the reference signal, and is different from the level of the reset signal in the reset stage; In the data input stage, the light emitting control signal is consistent with the level of the reference signal, and is consistent with the level of the reset signal in the data input stage; In the comparison light-emitting stage, the light-emitting control signal is a level for controlling the conduction of the first transistor, and is different from the level in the data input stage, and the reference signal changes linearly; The row scanning signal also includes a reset phase in each cycle. In the reset phase, the row scanning signal has a level consistent with that corresponding to the comparison light-emitting phase.

6. The display device according to claim 5, It is characterized in that The transistors among the first transistor, the second transistor, the third transistor, the fourth transistor, the fifth transistor, the sixth transistor, the seventh transistor, the eighth transistor, the ninth transistor, the tenth transistor and the eleventh transistor are P-type thin film transistors or N-type thin film transistors.

7. A display device, It is characterized in that include: Display panel and pixel driving circuit; The pixel driving circuit is configured as follows: When the light-emitting control signal is converted to a level for controlling the first transistor to be turned on, the light-emitting control signal is received through the control terminal of the first transistor, the first terminal receives the first voltage signal VGH, the first transistor is turned on, so that the second transistor is turned on, and the light-emitting control circuit controls the LED to emit light according to the signal generated by the second terminal of the second transistor; Receiving a linearly varying reference signal through one end of the first capacitor, so that the voltage of the first end of the second transistor at the other end of the first capacitor changes, so that the second transistor is turned off; The light emitting control signal is received through the control terminal of the third transistor, and the second terminal receives the second voltage signal VGL, the third transistor is turned on, so that when the second transistor is turned off, the voltage at the second terminal of the second transistor is set to VGL, and the light emitting control circuit controls the LED to stop emitting light according to the current voltage at the second terminal of the second transistor; Among them, the light-emitting control signal and the reference signal are both periodic signals, and the light-emitting control signal has a high-low level transition in each period. When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the reference signal is a linearly changing signal.

8. The display device according to claim 7, It is characterized in that The light emitting control circuit is configured as follows: When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the light-emitting control signal is received through the control terminal of the fourth transistor, the first terminal receives the first voltage signal VGH, and the fourth transistor is turned on to set the voltage of the first terminal of the fifth transistor to VGH; When the second transistor is turned on, the control terminal of the fifth transistor receives a signal generated by the second terminal, and the fifth transistor is turned off; The light-emitting control signal is received through the control terminal of the seventh transistor, the first terminal receives the third voltage signal VDD, the seventh transistor is turned on to set the voltage of the first terminal of the sixth transistor to VDD, the sixth transistor is turned on, and the LED emits light; The second voltage signal VGL transmitted by the third transistor when the second transistor is turned off is received through the fifth transistor control terminal, and the fifth transistor is turned on to turn off the sixth transistor, and the LED stops emitting light.

9. The display device according to claim 8, It is characterized in that The pixel driving circuit is further configured as follows: In the data input stage, the row scan signal is received through the control terminal of the eighth transistor, the first terminal receives the PWMD signal, the eighth transistor is turned on, so as to set the voltage of the control terminal of the second transistor to PWMD, and the second transistor is turned on; The row scanning signal is received through the control terminal of the ninth transistor, and the ninth transistor is turned on to perform threshold compensation on the second transistor; The row scan signal is received through the tenth transistor control terminal, and the first terminal receives the PAMD signal to set the voltage of the sixth transistor control terminal to PAMD; The row scanning signal is a periodic signal, and each period includes at least a data input stage and a comparison and light emission stage; in the data input stage and the comparison and light emission stage, the level of the row scanning signal and the light emission control signal in the corresponding stage are different.

10. A pixel driving circuit, It is characterized in that include: A first transistor, a control end of which is used to receive a light emitting control signal, a first end of which is used to receive a first voltage signal VGH, and a second end of which is connected to a control end of a second transistor; a first capacitor, one end of which is used to receive a reference signal, and the other end of which is connected to the first end of the second transistor; The second end of the second transistor is connected to the first end of the third transistor and the input end of the light emitting control circuit respectively; The control terminal of the third transistor is used to receive the light emitting control signal, and the second terminal is used to receive the second voltage signal VGL; The light emitting control circuit has an output end connected to the LED and is used to control the LED according to the signal generated by the second end of the second transistor; Among them, the light-emitting control signal and the reference signal are both periodic signals, and the light-emitting control signal has a high-low level transition in each period. When the light-emitting control signal is converted to a level for controlling the conduction of the first transistor, the reference signal is a linearly changing signal.

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