Pixel driving circuit, display apparatus, and driving method

Abstract

A pixel driving circuit, a display apparatus, and a driving method. The pixel driving circuit comprises: a driving transistor (DT), which is configured to generate a driving current according to a data voltage and a threshold voltage of the driving transistor (DT); a data writing sub-circuit (001), which is coupled to a gate electrode of the driving transistor (DT) and is configured to input, in response to a signal from a scanning signal end (Gate), a data voltage of a data signal end (Vdata) into the gate electrode of the driving transistor (DT); a threshold compensation sub-circuit (002), which is coupled to the driving transistor (DT) and is configured to provide, in response to a signal from a compensation signal end (CM), the threshold voltage of the driving transistor (DT) to the gate electrode of the driving transistor (DT); and a first light emission control sub-circuit (003), which is coupled to the driving transistor (DT) and is configured to provide, in response to a signal from a control signal end (EM), the driving current generated by the driving transistor (DT) to a light-emitting device (LED). By means of providing a pixel driving circuit, the influence of oxide characteristics on currents of a pixel circuit can be eliminated, thereby improving the light emission stability of a light-emitting device (LED) in the pixel circuit.

Description

Pixel driving circuit, display device and driving method

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on June 25, 2023, with application number 202310747576.3 and application name “A pixel driving circuit, display device and driving method”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present disclosure relates to the field of display technology and provides a pixel driving circuit, a display device, and a driving method. Background Art

[0004] For pixel circuits composed of full-oxide type driving transistors, the driving transistors are sensitive to oxide properties (light, water, oxygen, etc.), which can cause their threshold voltage to change. The change in threshold voltage can cause the current of the driving transistor to be unstable during the light-emitting process, and the light-emitting devices in the pixel circuits will flicker.

[0005] Summary of the Invention

[0006] Embodiments of the present disclosure provide a pixel driving circuit, a display device, and a driving method, for reducing the impact of unstable light emission of a light-emitting device caused by a change in threshold voltage.

[0007] The specific technical solutions provided by this disclosure are as follows:

[0008] In a first aspect, a pixel driving circuit includes: a driving transistor, a light-emitting device, a data writing subcircuit, a threshold compensation subcircuit, and a first light-emitting control subcircuit;

[0009] a driving transistor configured to generate a driving current according to a data voltage and a threshold voltage of the driving transistor;

[0010] The data writing sub-circuit is coupled to the gate of the driving transistor and is configured to input the data voltage of the data signal terminal into the gate of the driving transistor in response to the signal of the scanning signal terminal;

[0011] The threshold compensation sub-circuit is coupled to the driving transistor and is configured to provide a threshold voltage of the driving transistor to a gate of the driving transistor in response to a signal at the compensation signal terminal;

[0012] The first light emitting control subcircuit is coupled to the driving transistor and is configured to provide the driving current generated by the driving transistor to the light emitting device in response to a signal at the control signal terminal.

[0013] Optionally, the threshold compensation subcircuit includes a first switching transistor and a first capacitor;

[0014] The control terminal of the first switch transistor is coupled to the compensation signal terminal, the first terminal of the first switch transistor is coupled to the gate of the driving transistor, and the second terminal of the first switch transistor is coupled to the second electrode of the driving transistor;

[0015] A first terminal of the first capacitor is coupled to the gate of the driving transistor, and a second terminal of the first capacitor is coupled to the second electrode of the driving transistor.

[0016] Optionally, the data writing sub-circuit includes a second switching transistor;

[0017] The control end of the second switch transistor is coupled to the scan signal end, the first end of the second switch transistor is coupled to the data signal end, and the second end of the second switch transistor is coupled to the gate of the driving transistor.

[0018] Optionally, the first light emitting control subcircuit includes a third switching transistor;

[0019] The control terminal of the third switch transistor is coupled to the control signal terminal, the first terminal of the third switch transistor is coupled to the first power terminal, and the second terminal of the third switch transistor is coupled to the first electrode of the driving transistor.

[0020] Optionally, a first reset subcircuit is further included, which is coupled to the first electrode of the driving transistor and provides the signal of the reference signal terminal to the first electrode of the driving transistor in response to the signal of the first reset signal terminal.

[0021] Optionally, the first reset sub-circuit includes a fourth switching transistor;

[0022] The control terminal of the fourth switch transistor is coupled to the first reset signal terminal, the first terminal of the fourth switch transistor is coupled to the reference signal terminal, and the second terminal of the fourth switch transistor is coupled to the first electrode of the driving transistor.

[0023] Optionally, a second reset circuit is further included, which is coupled to the gate of the driving transistor and is configured to provide an initialization signal from an initialization signal terminal to the gate of the driving transistor in response to a signal from a second reset signal terminal.

[0024] Optionally, the second reset circuit includes a fifth switching transistor;

[0025] The control terminal of the fifth switch transistor is coupled to the second reset signal terminal, the first terminal of the fifth switch transistor is coupled to the initialization signal terminal, and the second terminal of the fifth switch transistor is coupled to the gate of the driving transistor.

[0026] Optionally, the second electrode of the driving transistor is coupled to the light emitting device and the threshold compensation sub-circuit.

[0027] Optionally, a second light emitting control subcircuit is further included, and the second electrode of the driving transistor is coupled to the light emitting device and the threshold compensation subcircuit via the second light emitting control subcircuit;

[0028] The second light emitting control sub-circuit is configured to connect the second electrode of the driving transistor to the light emitting device in response to a signal at the control signal terminal.

[0029] Optionally, the second light emitting control subcircuit includes a sixth switching transistor;

[0030] The control terminal of the sixth switch transistor is coupled to the control signal terminal, the first terminal of the sixth switch transistor is coupled to the second electrode of the driving transistor, and the second terminal of the sixth switch transistor is coupled to the light emitting device.

[0031] Optionally, a second capacitor is further included, wherein the first electrode of the second capacitor is coupled to the second electrode of the driving transistor, and the second electrode of the second capacitor is coupled to the fixed voltage signal end, and the fixed voltage signal end is the first power supply end or the second power supply end.

[0032] Optionally, the driving transistor is a single-gate transistor or a double-gate transistor;

[0033] When the driving transistor is a dual-gate transistor, the first gate of the driving transistor is coupled to the data writing sub-circuit, and the second gate of the driving transistor is coupled to the second power supply terminal.

[0034] Optionally, the polarity of the first switch transistor, the second switch transistor, the third switch transistor, the fourth switch transistor and the fifth switch transistor is N-type.

[0035] In a second aspect, a display device includes any one of the above pixel driving circuits.

[0036] In a third aspect, a driving method of a pixel driving circuit as described in any one of the above items includes:

[0037] The second reset subcircuit resets the anode of the light emitting device via the fifth switch transistor and the first switch transistor;

[0038] The data writing sub-circuit inputs the data voltage of the data signal terminal into the gate of the driving transistor in response to the signal of the scanning signal terminal;

[0039] The threshold compensation subcircuit provides the threshold voltage of the driving transistor to the gate of the driving transistor in response to the signal at the compensation signal terminal;

[0040] The driving transistor generates a driving current according to the data voltage and a threshold voltage of the driving transistor;

[0041] The first light emitting control subcircuit provides the driving current generated by the driving transistor to the light emitting device in response to the signal at the control signal terminal.

[0042] The beneficial effects of the present disclosure are as follows:

[0043] In summary, the present disclosure provides a pixel driving circuit, a display device, and a driving method. The pixel driving circuit includes: a driving transistor, a light-emitting device, a data writing sub-circuit, a threshold compensation sub-circuit, and a first light-emitting control sub-circuit. During implementation, the driving transistor is configured to generate a driving current based on a data voltage and a threshold voltage of the driving transistor. The data writing sub-circuit is coupled to the gate of the driving transistor and is configured to input the data voltage of the data signal end into the gate of the driving transistor in response to a signal at a scanning signal end. The threshold compensation sub-circuit is coupled to the driving transistor and is configured to provide the threshold voltage of the driving transistor to the gate of the driving transistor in response to a signal at a compensation signal end. The first light-emitting control sub-circuit is coupled to the driving transistor and is configured to provide the driving current generated by the driving transistor to the light-emitting device in response to a signal at a control signal end. The above-mentioned setting of the pixel driving circuit can eliminate the influence of oxide characteristics on the current of the pixel circuit and improve the light-emitting stability of the light-emitting device in the pixel circuit.

[0044] Other features and advantages of the present disclosure will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present disclosure. The purposes and other advantages of the present disclosure can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present disclosure. The exemplary embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation of the present disclosure. In the drawings:

[0046] FIG1 is a connection diagram of a pixel driving circuit according to an embodiment of the present disclosure;

[0047] FIG2 is a circuit connection diagram of a first pixel driving circuit in an embodiment of the present disclosure;

[0048] FIG3 is a connection diagram of another pixel driving circuit in an embodiment of the present disclosure;

[0049] FIG4 is a circuit connection diagram of a second pixel driving circuit in an embodiment of the present disclosure;

[0050] FIG5 is a circuit connection diagram of a third pixel driving circuit in an embodiment of the present disclosure;

[0051] FIG6 is a circuit connection diagram of a fourth pixel driving circuit in an embodiment of the present disclosure;

[0052] FIG7 is a circuit connection diagram of a fifth pixel driving circuit in an embodiment of the present disclosure;

[0053] FIG8 is a circuit connection diagram of a sixth pixel driving circuit in an embodiment of the present disclosure;

[0054] FIG9 is a timing diagram corresponding to the second pixel driving circuit in an embodiment of the present disclosure;

[0055] FIG10 is a flow chart of a driving method of a pixel driving circuit according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0056] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the technical solutions of the present disclosure, but not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments described in this disclosure without making any creative efforts shall fall within the scope of protection of the technical solutions of the present disclosure.

[0057] The terms "first," "second," and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present invention described herein can be practiced using orders other than those illustrated or described herein.

[0058] In related technologies, the driving transistor is sensitive to oxide properties (light, water, oxygen, etc.), which can cause its threshold voltage to change. The change in threshold voltage can cause the current of the driving transistor to be unstable during the light-emitting process, and the light-emitting device in the pixel circuit will flicker.

[0059] The preferred embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0060] 1 , a pixel driving circuit provided in an embodiment of the present disclosure includes: a driving transistor DT, a light-emitting device LED, a data writing sub-circuit 001 , a threshold compensation sub-circuit 002 and a first light-emitting control sub-circuit 003 .

[0061] During implementation, the driving transistor DT is configured to generate a driving current according to the data voltage and the threshold voltage of the driving transistor DT.

[0062] The data writing sub-circuit 001 is coupled to the gate of the driving transistor DT and is configured to input the data voltage of the data signal terminal Vdata into the gate of the driving transistor DT in response to the signal of the scanning signal terminal Gate.

[0063] The threshold compensation sub-circuit 002 is coupled to the driving transistor DT and is configured to provide the threshold voltage of the driving transistor DT to the gate of the driving transistor DT in response to the signal of the compensation signal terminal CM.

[0064] The first light emitting control sub-circuit 003 is coupled to the driving transistor DT and is configured to provide the driving current generated by the driving transistor DT to the light emitting device LED in response to a signal from the control signal terminal EM.

[0065] Referring to FIG. 2 , the threshold compensation sub-circuit 002 includes a first switch transistor T1 and a first capacitor C1 .

[0066] The connection relationship between the first switch transistor T1 and other components in Figure 2 is: the control end of the first switch transistor T1 is coupled to the compensation signal end CM, the first end of the first switch transistor T1 is coupled to the gate of the driving transistor DT, and the second end of the first switch transistor T1 is coupled to the second electrode of the driving transistor DT.

[0067] During implementation, when the signal at the compensation signal terminal CM is a high voltage, the first switch transistor T1 is turned on.

[0068] The connection relationship between the first capacitor C1 and other components in FIG. 2 is as follows: a first end of the first capacitor C1 is coupled to the gate of the driving transistor DT, and a second end of the first capacitor C1 is coupled to the second electrode of the driving transistor DT.

[0069] During implementation, the first capacitor C1 is used to store the threshold voltage of the driving transistor DT.

[0070] 2 , the data writing sub-circuit 001 includes a second switch transistor T2 .

[0071] The connection relationship between the second switch transistor T2 and other components in Figure 2 is: the control end of the second switch transistor T2 is coupled to the scan signal end Gate, the first end of the second switch transistor T2 is coupled to the data signal end Vdata, and the second end of the second switch transistor T2 is coupled to the gate of the driving transistor DT.

[0072] During implementation, when the signal at the scan signal terminal Gate is at a high voltage, the second switch transistor T2 is turned on, and the signal at the data signal terminal Vdata reaches the first node via the turned-on second switch transistor T2.

[0073] 2 , the first light emitting control sub-circuit 003 includes a third switch transistor T3 .

[0074] The connection relationship between the third switch transistor T3 and other components in Figure 2 is: the control end of the third switch transistor T3 is coupled to the control signal end EM, the first end of the third switch transistor T3 is coupled to the first power supply end Vdd, and the second end of the third switch transistor T3 is coupled to the first electrode of the driving transistor DT.

[0075] During implementation, when the signal at the control signal terminal EM is at a high voltage, the third switch transistor T3 is turned on, and the signal at the first power supply terminal Vdd reaches the driving transistor DT via the turned-on third switch transistor T3.

[0076] 3 , the pixel driving circuit further includes a first reset sub-circuit 004 coupled to the first electrode of the driving transistor DT and providing a signal from the reference signal terminal Vref to the first electrode of the driving transistor DT in response to a signal from the first reset signal terminal Re_1.

[0077] During implementation, the first reset sub-circuit 004 is mainly used to reset the third node of the driving transistor DT.

[0078] Referring to FIG. 4 , the first reset sub-circuit 004 includes a fourth switch transistor T4 .

[0079] The connection relationship between the fourth switch transistor T4 and other components in Figure 4 is: the control end of the fourth switch transistor T4 is coupled to the first reset signal end Re_1, the first end of the fourth switch transistor T4 is coupled to the reference signal end Vref, and the second end of the fourth switch transistor T4 is coupled to the first electrode of the driving transistor DT.

[0080] During implementation, when the signal at the first reset signal terminal Re_1 is at a high voltage, the fourth switch transistor T4 is turned on, and the signal at the reference signal terminal Vref reaches the third node via the turned-on fourth switch transistor T4.

[0081] 4 , the pixel driving circuit further includes a second reset circuit coupled to the gate of the driving transistor DT. The second reset circuit is configured to provide an initialization signal of the initialization signal terminal Vinit to the gate of the driving transistor DT in response to a signal of the second reset signal terminal Re_2.

[0082] During implementation, the second reset sub-circuit 005 is mainly used to reset the first node of the driving transistor DT.

[0083] Referring to FIG. 4 , the second reset circuit includes a fifth switch transistor T5 .

[0084] The connection relationship between the fifth switch transistor T5 and other components in Figure 4 is: the control end of the fifth switch transistor T5 is coupled to the second reset signal end Re_2, the first end of the fifth switch transistor T5 is coupled to the initialization signal end Vinit, and the second end of the fifth switch transistor T5 is coupled to the gate of the driving transistor DT.

[0085] During implementation, when the signal at the second reset signal terminal Re_2 is a high voltage, the fifth switch transistor T5 is turned on, and the signal at the initialization signal terminal Vinit reaches the first node via the turned-on fifth switch transistor T5.

[0086] 4 , the second electrode of the driving transistor DT is coupled to the light emitting device LED and the threshold compensation sub-circuit 002 .

[0087] 4 , the pixel driving circuit further includes a second light emitting control sub-circuit 006 , through which the second electrode of the driving transistor DT is coupled to the light emitting device LED and the threshold compensation sub-circuit 002 .

[0088] During implementation, the second light emitting control sub-circuit 006 is configured to connect the second electrode of the driving transistor DT to the light emitting device LED in response to a signal from the control signal terminal EM.

[0089] 5 , the second light emitting control sub-circuit 006 includes a sixth switch transistor T6 .

[0090] The connection relationship between the sixth switch transistor T6 and other components in Figure 5 is: the control end of the sixth switch transistor T6 is coupled to the control signal end EM, the first end of the sixth switch transistor T6 is coupled to the second electrode of the driving transistor DT, and the second end of the sixth switch transistor T6 is coupled to the light-emitting device LED.

[0091] During implementation, when the signal at the control signal terminal EM is at a high voltage, the sixth switch transistor T6 is turned on, and the signal at the first power supply terminal Vdd passes through the driving transistor DT and the turned-on sixth switch transistor T6 to the light-emitting device LED. The sixth switch transistor T6 can be turned on and off according to a preset PWM waveform, thereby further controlling the on and off of the light-emitting device LED. Specifically, to achieve a more refined light-emitting current for the light-emitting device LED, the sixth switch transistor T6 can be configured to have a PWM waveform.

[0092] 6 and 7 , the pixel driving circuit further includes a second capacitor C2, a first electrode of the second capacitor C2 being coupled to the second electrode of the driving transistor DT, and a second electrode of the second capacitor C2 being coupled to a fixed voltage signal terminal, which is the first power supply terminal Vdd or the second power supply terminal Vss.

[0093] The original luminous current of the light-emitting device LED is generated by the data voltage of the data signal terminal Vdata through the first capacitor C1 and the driving transistor DT. After the above-mentioned second capacitor C2 is set, the luminous current of the light-emitting device LED is generated by the data voltage of the data signal terminal Vdata through the first capacitor C1, the second capacitor C2 and the driving transistor DT. This can make the luminous current of the light-emitting device LED more delicate during the light-emitting stage.

[0094] In order to make the circuit connection more flexible, in other embodiments, the driving transistor DT is a single-gate transistor or a double-gate transistor.

[0095] When the driving transistor DT is a single-gate transistor, its connection mode in the above pixel driving circuit is as shown in any one of FIG. 2 , FIG. 4 , FIG. 5 , FIG. 6 or FIG. 7 .

[0096] When the driving transistor DT is a dual-gate transistor, referring to FIG8 , a first gate of the driving transistor DT is coupled to the data writing sub-circuit 001 , and a second gate of the driving transistor DT is coupled to the second power supply terminal Vss.

[0097] When the second gate of the driving transistor DT is coupled to the second power supply terminal Vss, the driving transistor DT can be shielded from light.

[0098] It should be additionally explained that the polarity of the first switch transistor, the second switch transistor, the third switch transistor, the fourth switch transistor and the fifth switch transistor is N-type.

[0099] 9 , after introducing the circuit connection of the above pixel driving circuit, the working process of the above pixel driving circuit will be described in detail with reference to the timing diagram.

[0100] Timing stage t1: Re_1=1, Re_2=1, CM=1, EM=0, Gate=0

[0101] When the first reset signal terminal Re_1 is at a high voltage, the fourth switching transistor is turned on, and the signal at the reference signal terminal Vref reaches the third node N3 via the turned-on fourth switching transistor. The voltage at the third node N3 is Vref. When the second reset signal terminal Re_2 is at a high voltage, the fifth switching transistor is turned on, and the initialization signal terminal Vinit signal reaches the first node N1 via the turned-on fifth switching transistor. Simultaneously, the signal at the compensation signal terminal CM is at a high voltage, the first switching transistor is turned on, and the initialization signal terminal Vinit signal reaches the second node N2 via the first node N1 and the turned-on first switching transistor. Since Vinit is greater than Vref, the gate-source voltage of the drive transistor DT is Vgs = Vinit - Vref. Furthermore, since Vgs is greater than Vth, the drive transistor DT is turned on.

[0102] Timing t2 stage: Re_1 = 1, Re_2 = 1, CM = 0, EM = 0, Gate = 0

[0103] When the first reset signal terminal Re_1 is at a high voltage, the fourth switching transistor is turned on, and the signal at the reference signal terminal reaches the third node N3 via the turned-on fourth switching transistor. The voltage at the third node N3 is Vref. When the second reset signal terminal Re_2 is at a high voltage, the fifth switching transistor is turned on, and the signal Vinit at the initialization signal terminal reaches the first node N1 via the turned-on fifth switching transistor. At the same time, the signal at the compensation signal terminal CM is at a low voltage, and the first switching transistor is turned off. The signal at the reference signal terminal Vref reaches the second node N2 via the turned-on fourth switching transistor and the turned-on driving transistor. The voltage at the second node N2 is Vref.

[0104] Timing t3 stage: Re_1 = 0, Re_2 = 1, CM = 0, EM = 1, Gate = 0

[0105] When the first reset signal terminal Re_1 is a low voltage, the fourth switch transistor is turned off; when the second reset signal terminal Re_2 is a high voltage, the fifth switch transistor is turned on, the signal of the compensation signal terminal CM is a low voltage, the first switch transistor is turned off, the signal of the control signal terminal EM is a high voltage, the third switch transistor is turned on, and the signal of the first power supply terminal Vdd reaches the second node N2 through the turned-on third switch transistor and the driving transistor. In the process of the voltage of the second node N2 changing to VDD, specifically, when the voltage of the second node N2 changes to Vinit-Vth, the driving transistor is turned off, the gate-source voltage of the driving transistor is reset, and the threshold voltage Vth of the driving transistor is written into the first node N1.

[0106] Timing stage t4: Re_1 = 0, Re_2 = 0, CM = 0, EM = 0, Gate = 1

[0107] When the first reset signal terminal Re_1 is a low voltage, the fourth switch transistor is turned off; when the second reset signal terminal Re_2 is a low voltage, the fifth switch transistor is turned off; the signal at the compensation signal terminal CM is a low voltage, the first switch transistor is turned off; when the signal at the control signal terminal EM is a low voltage, the third switch transistor is turned off; when the signal at the scan signal terminal Gate is a high voltage, the second switch transistor is turned on, and the data voltage of the data signal terminal Vdata is input to the gate of the driving transistor.

[0108] Timing stage t5: Re_1 = 0, Re_2 = 0, CM = 0, EM = 1, Gate = 0

[0109] When the first reset signal terminal Re_1 is at a low voltage, the fourth switch transistor is turned off; when the second reset signal terminal Re_2 is at a low voltage, the fifth switch transistor is turned off; the signal at the compensation signal terminal CM is at a low voltage, the first switch transistor is turned off; when the signal at the control signal terminal EM is at a high voltage, the third switch transistor is turned on, the driving transistor is turned on under the action of the first power supply terminal Vdd, and the data voltage at the gate of the driving transistor causes the light-emitting device LED to emit light through the turned-on driving transistor; when the signal at the scanning signal terminal Gate is at a low voltage, the second switch transistor is turned off.

[0110] The light-emitting current of the above-mentioned light-emitting device LED is I=1 / 2k(Vgs-Vth) 2 Formula (1)

[0111] In the above formula (1), k is a constant, Vgs is the gate-source voltage of the driving transistor, and Vth is the threshold voltage of the driving transistor.

[0112] The gate-source voltage of the driving transistor Vgs = (Vdata - Vinit) * (Coled / C1 + Coled) + Vth Formula (2)

[0113] In the above formula (2), Vdata is the data voltage of the data signal terminal, Vinit is the initialization signal of the initialization signal terminal, Coled is the capacitance value of the light emitting device, C1 is the capacitance value of the first capacitor, and Vth is the threshold voltage of the driving transistor.

[0114] Substituting formula (2) into formula (1), the simplified formula of light-emitting current is I = 1 / 2k[(Vdata-Vinit)*(Coled / C1+Coled)+Vth-Vth] 2 =1 / 2k[(Vdata-Vinit)*(Coled / C1+Coled)] 2

[0115] The formula for the luminous current is (3): I = 1 / 2k[(Vdata-Vinit)*(Coled / C1+Coled)] 2 Formula (3)

[0116] It can be seen from the above formula (3) that, through the configuration of the above pixel driving circuit, the light-emitting current of the light-emitting device is independent of the threshold voltage Vth of the driving transistor.

[0117] In the above formula (3), k is a constant, Vdata is the data voltage of the data signal terminal, Vinit is the initialization signal of the initialization signal terminal, Coled is the capacitance value of the light emitting device, and C1 is the capacitance value of the first capacitor.

[0118] Furthermore, after adding the second capacitor, the light-emitting current of the light-emitting device is I=1 / 2k[(Vdata-Vinit)*(Coled+C2 / C1+Coled+C2)] 2 Formula (4).

[0119] In the above formula (4), k is a constant, Vdata is the data voltage of the data signal terminal, Vinit is the initialization signal of the initialization signal terminal, Coled is the capacitance value of the light-emitting device, C1 is the capacitance value of the first capacitor, and C2 is the capacitance value of the second capacitor.

[0120] Based on the same inventive concept, an embodiment of the present disclosure provides a display device comprising any of the above-mentioned pixel driving circuits.

[0121] In the embodiments of the present invention, the display device may be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, or a navigation system. Other essential components of the display device are well understood by those skilled in the art and are not described in detail herein, nor should they be construed as limiting the present invention.

[0122] Based on the same inventive concept, an embodiment of the present disclosure provides a driving method for a pixel driving circuit, as shown in FIG10 , including:

[0123] Step 200: The second reset sub-circuit resets the anode of the light-emitting device via the fifth switch transistor and the first switch transistor.

[0124] Step 201: The data writing sub-circuit inputs the data voltage at the data signal terminal into the gate of the driving transistor in response to the signal at the scanning signal terminal.

[0125] During implementation, when the signal at the scan signal end is at a high level, the second switch transistor is turned on, and the data voltage at the data signal end is input to the gate of the driving transistor through the second switch transistor and the first node.

[0126] Step 202: The threshold compensation sub-circuit provides the threshold voltage of the driving transistor to the gate of the driving transistor in response to the signal at the compensation signal terminal.

[0127] During implementation, when the signal at the compensation signal terminal is at a high level, the first switch transistor is turned on, and the threshold voltage of the driving transistor is provided to the gate of the driving transistor via the turned-on first switch transistor.

[0128] Step 203: the driving transistor generates a driving current according to the data voltage and the threshold voltage of the driving transistor.

[0129] During the implementation, in the light emitting stage, the driving transistor generates a driving current according to a predetermined current formula data voltage and a threshold voltage of the driving transistor.

[0130] Step 204: the first light emitting control sub-circuit provides the driving current generated by the driving transistor to the light emitting device in response to the signal at the control signal terminal.

[0131] In the light-emitting stage, when the signal at the control signal terminal is at a high level, the third switch transistor is turned on, and the driving current generated by the driving transistor is provided to the light-emitting device.

[0132] In summary, the embodiments of the present disclosure provide a pixel driving circuit, a display device, and a driving method. The pixel driving circuit includes: a driving transistor, a light-emitting device, a data writing sub-circuit, a threshold compensation sub-circuit, and a first light-emitting control sub-circuit. During implementation, the driving transistor is configured to generate a driving current based on a data voltage and a threshold voltage of the driving transistor. The data writing sub-circuit is coupled to the gate of the driving transistor and is configured to input the data voltage of the data signal end into the gate of the driving transistor in response to a signal at a scanning signal end. The threshold compensation sub-circuit is coupled to the driving transistor and is configured to provide the threshold voltage of the driving transistor to the gate of the driving transistor in response to a signal at a compensation signal end. The first light-emitting control sub-circuit is coupled to the driving transistor and is configured to provide the driving current generated by the driving transistor to the light-emitting device in response to a signal at a control signal end. The setting of the above-mentioned pixel driving circuit can eliminate the influence of oxide characteristics on the current of the pixel circuit and improve the light-emitting stability of the light-emitting device in the pixel circuit.

[0133] Those skilled in the art will appreciate that the embodiments of the present disclosure may be provided as methods, systems, or computer program product systems. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present disclosure may take the form of a computer program product system implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0134] The present disclosure is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program product systems according to the present disclosure. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0135] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0136] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes of the flowchart and / or one or more blocks of the block diagram. Obviously, those skilled in the art can make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is also intended to include such modifications and variations.

Claims

1. A pixel driving circuit, wherein: include: A driving transistor, a light emitting device, a data writing sub-circuit, a threshold compensation sub-circuit and a first light emitting control sub-circuit; The driving transistor is configured to generate a driving current according to a data voltage and a threshold voltage of the driving transistor; The data writing sub-circuit is coupled to the gate of the driving transistor and is configured to input a data voltage at a data signal terminal into the gate of the driving transistor in response to a signal at a scanning signal terminal; The threshold compensation subcircuit is coupled to the driving transistor and is configured to provide the threshold voltage of the driving transistor to the gate of the driving transistor in response to a signal at a compensation signal terminal; The first light emitting control subcircuit is coupled to the driving transistor, and is configured to provide the driving current generated by the driving transistor to the light emitting device in response to a signal at a control signal terminal.

2. The pixel driving circuit according to claim 1, wherein: The threshold compensation subcircuit includes a first switch transistor and a first capacitor; The control terminal of the first switch transistor is coupled to the compensation signal terminal, the first terminal of the first switch transistor is coupled to the gate of the driving transistor, and the second terminal of the first switch transistor is coupled to the second electrode of the driving transistor; A first terminal of the first capacitor is coupled to the gate of the driving transistor, and a second terminal of the first capacitor is coupled to the second electrode of the driving transistor.

3. The pixel driving circuit according to claim 1, wherein: The data writing subcircuit includes a second switch transistor; The control terminal of the second switch transistor is coupled to the scan signal terminal, the first terminal of the second switch transistor is coupled to the data signal terminal, and the second terminal of the second switch transistor is coupled to the gate of the driving transistor.

4. The pixel driving circuit according to claim 1, wherein: The first light emitting control subcircuit comprises a third switching transistor; The control terminal of the third switch transistor is coupled to the control signal terminal. The first terminal of the body transistor is coupled to the first power supply terminal, and the second terminal of the third switch transistor is coupled to the first electrode of the driving transistor.

5. The pixel driving circuit according to any one of claims 1 to 4, wherein: The circuit also includes a first reset subcircuit, which is coupled to the first electrode of the driving transistor and provides a signal from a reference signal terminal to the first electrode of the driving transistor in response to a signal from a first reset signal terminal.

6. The pixel driving circuit according to claim 5, wherein: The first reset subcircuit includes a fourth switch transistor; The control terminal of the fourth switch transistor is coupled to the first reset signal terminal, the first terminal of the fourth switch transistor is coupled to the reference signal terminal, and the second terminal of the fourth switch transistor is coupled to the first electrode of the driving transistor.

7. The pixel driving circuit according to any one of claims 1 to 4, wherein: It also includes a second reset subcircuit, which is coupled to the gate of the driving transistor and is configured to provide an initialization signal at an initialization signal terminal to the gate of the driving transistor in response to a signal at a second reset signal terminal.

8. The pixel driving circuit according to claim 7, wherein: The second reset subcircuit includes a fifth switch transistor; The control terminal of the fifth switch transistor is coupled to the second reset signal terminal, the first terminal of the fifth switch transistor is coupled to the initialization signal terminal, and the second terminal of the fifth switch transistor is coupled to the gate of the driving transistor.

9. The pixel driving circuit according to any one of claims 1 to 4, wherein: The second electrode of the driving transistor is coupled to the light emitting device and the threshold compensation sub-circuit.

10. The pixel driving circuit according to any one of claims 1 to 4, wherein: It also includes a second light emitting control subcircuit, and the second electrode of the driving transistor is coupled to the light emitting device and the threshold compensation subcircuit through the second light emitting control subcircuit; The second light emitting control sub-circuit is configured to connect the second electrode of the driving transistor to the light emitting device in response to a signal at the control signal terminal.

11. The pixel driving circuit according to claim 9, wherein: The second light emitting control subcircuit comprises a sixth switch transistor; The control terminal of the sixth switch transistor is coupled to the control signal terminal, the first terminal of the sixth switch transistor is coupled to the second electrode of the driving transistor, and the second terminal of the sixth switch transistor is coupled to the light emitting device.

12. The pixel driving circuit according to any one of claims 1 to 4, wherein: It also includes a second capacitor, a first electrode of the second capacitor is coupled to the second electrode of the driving transistor, and a second electrode of the second capacitor is coupled to a fixed voltage signal terminal, and the fixed voltage signal terminal is the first power supply terminal or the second power supply terminal.

13. The pixel driving circuit according to any one of claims 1 to 11, wherein: The driving transistor is a single-gate transistor or a double-gate transistor; When the driving transistor is a dual-gate transistor, the first gate of the driving transistor is coupled to the data writing sub-circuit, and the second gate of the driving transistor is coupled to the second power supply terminal.

14. The pixel driving circuit according to any one of claims 1 to 11, wherein: The polarities of the first switch transistor, the second switch transistor, the third switch transistor, the fourth switch transistor and the fifth switch transistor are N-type.

15. A display device, wherein: Comprising the pixel driving circuit as described in any one of claims 1-14.

16. A driving method for a pixel driving circuit according to any one of claims 1 to 14, wherein: include: The second reset subcircuit resets the anode of the light emitting device via the fifth switch transistor and the first switch transistor; The data writing subcircuit inputs the data voltage of the data signal terminal into the gate of the driving transistor in response to the signal of the scanning signal terminal; The threshold compensation subcircuit provides the threshold voltage of the driving transistor to the gate of the driving transistor in response to a signal at a compensation signal terminal; The driving transistor generates a driving current according to the data voltage and a threshold voltage of the driving transistor; The first light emitting control subcircuit responds to the signal at the control signal terminal to control the driving transistor to generate The driving current is provided to the light emitting device.

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