Pixel compensation circuit and method, pixel circuit, display panel and electronic equipment

Abstract

The invention relates to a pixel compensation circuit and method, a pixel circuit, a display panel and electronic equipment. The pixel compensation circuit comprises a driving module, a compensation module and an input module, a driving transistor control end of the driving module receives first node voltage, a first end receives second node voltage, and a second end receives third node voltage and provides driving current for a light emitting device; the first end of a first switch tube and the first end of a second switch tube of the compensation module are used for inputting reference voltage, the second end of the first switch tube and the first end of a first capacitor are connected with the control end of a driving transistor at a first node, and the second end of the second switch tube is connected with the first end of the driving transistor at a second node. The second end of the first capacitor and the first end of the second capacitor are connected with the second end of the driving transistor at a third node; the first end of an input switch tube of the input module receives data voltage, and the second end is connected with the control end of the driving transistor. Through the mode, the phenomenon of non-uniform picture display caused by inconsistent threshold voltage of the driving transistor is effectively improved.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a pixel compensation circuit and method, a pixel circuit, a display panel and an electronic device. Background Art

[0002] OLED (Organic Light-Emitting Diode) is an emerging flat panel display device. It has broad application prospects due to its advantages such as self-luminescence, high contrast, wide color gamut, simple preparation process, low cost, low power consumption, and easy to achieve flexible display.

[0003] In the related art, the brightness of the light-emitting diode OLED is determined by the data voltage Vdata, the power supply voltage ELVDD and the threshold voltage Vth of the thin film transistor. Due to the factors of the manufacturing process, the thin film transistors made on the large-area glass substrate have differences in the distribution of the threshold voltage Vth. At the same time, after the power supply voltage ELVDD is input from the outside of the effective display area, it is transmitted to each pixel circuit through the wire in the effective display area. During the transmission process, since the wire has a certain resistance, the power supply voltage ELVDD will produce a DC voltage drop during the transmission process, which is often called IR drop. Due to the existence of IR drop, the distribution of the power supply voltage ELVDD in the effective display area is uneven, combined with the distribution difference of the threshold voltage Vth of the thin film transistor, resulting in differences in the brightness of the display of two adjacent pixels even if the same data voltage Vdata is input (Mura). Summary of the invention

[0004] In view of this, the present disclosure proposes a pixel compensation circuit and method, a pixel circuit, a display panel and an electronic device.

[0005] According to one aspect of the present disclosure, a pixel compensation circuit is provided, which is used to drive a light-emitting device. The pixel compensation circuit includes: a driving module, the driving module includes a driving transistor, the control end of the driving transistor receives a first node voltage, the first end of the driving transistor receives a second node voltage, the second end of the driving transistor receives a third node voltage and provides a driving current to the light-emitting device; a compensation module, the compensation module includes a first capacitor, a second capacitor, a first switch tube, and a second switch tube, the first end of the first switch tube and the first end of the second switch tube are used to input a reference voltage, the second end of the first switch tube and the first end of the first capacitor are connected to the control end of the driving transistor at a first node, the second end of the second switch tube is connected to the first end of the driving transistor at a second node, and the second end of the first capacitor and the first end of the second capacitor are connected to the second end of the driving transistor at a third node; an input module, the input module includes an input switch tube, the first end of the input switch tube receives a data voltage corresponding to grayscale data, and the second end of the input switch tube is connected to the control end of the driving transistor.

[0006] In a possible implementation, the pixel compensation circuit also includes a reset module, which includes a third switch tube and a fourth switch tube, the control end of the third switch tube is connected to the control end of the fourth switch tube, the first end of the third switch tube is connected to the second end of the second capacitor for receiving a first input voltage, the second end of the third switch tube is connected to the third node, and is used to provide the first input voltage to the second end of the driving transistor and the first end of the second capacitor, the first end of the fourth switch tube is used to receive the second input voltage, and the second end of the fourth switch tube is connected to the fourth node, and is used to provide the second input voltage to the light-emitting device.

[0007] In a possible implementation, the driving module also includes a fifth switch tube and a sixth switch tube, the first end of the fifth switch tube receives the power supply voltage, the second end of the fifth switch tube is connected to the second node, the first end of the sixth switch tube is connected to the third node, and the second end of the sixth switch tube is connected to the fourth node.

[0008] In a possible implementation, the working cycle of the pixel compensation circuit includes: in a reset stage, the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, and the driving transistor are turned on, and the reset module is configured to control the second end of the driving transistor to receive the first input voltage, and control the input end of the light-emitting device to receive the second input voltage; the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, so that the voltage difference between the gate and the source of the driving transistor is a preset value; in a voltage compensation stage, the first switch tube, the second switch tube, and the driving transistor are turned on, and the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, and control the second switch tube and the driving transistor to receive the reference voltage. The body tube charges the third node until the third node voltage becomes the difference between the reference voltage and the threshold voltage; in the writing stage, the input switch tube is turned on, the data voltage is transmitted to the control end of the driving transistor, and the third node voltage becomes a writing voltage determined based on the reference voltage, the threshold voltage, the data voltage, the first capacitor and the second capacitor; in the light-emitting stage, the fifth switch tube, the sixth switch tube and the driving transistor are turned on, the first node voltage is a first sum voltage of the data voltage and the offset voltage, the third node voltage is a second sum voltage of the write voltage and the offset voltage, and the light-emitting device generates an effective brightness corresponding to the data voltage according to the driving current in the light-emitting stage, and the offset voltage is the voltage change caused by the turning on of the driving transistor.

[0009] In one possible implementation, the working cycle of the pixel compensation circuit also includes: in the bias compensation stage, the second switch tube is turned on, and the compensation module is configured to control the first end of the driving transistor to receive the reference voltage so that the voltage difference between the gate and the source of the driving transistor is the difference between the first sum voltage and the reference voltage.

[0010] In a possible implementation, the driving transistor, the input switch tube, and the first switch tube are N-type channel thin film transistors, and the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, and the sixth switch tube are N-type channel thin film transistors or P-type channel thin film transistors.

[0011] According to another aspect of the present disclosure, a pixel compensation method is provided, the pixel compensation method is applied to a pixel compensation circuit, the pixel compensation circuit includes a driving module, a compensation module, and an input module, the driving module includes a driving transistor, the compensation module includes a first capacitor, a second capacitor, a first switch tube, and a second switch tube, and the input module includes an input switch tube; the pixel compensation method is used to drive a light-emitting device, and the pixel compensation method includes: the control end of the driving transistor receives a first node voltage, the first end of the driving transistor receives a second node voltage, and the second end of the driving transistor receives a third node voltage and provides a driving current to the light-emitting device; the first end of the first switch tube and the first end of the second switch tube are used to input a reference voltage, the second end of the first switch tube and the first end of the first capacitor are connected to the control end of the driving transistor at a first node, the second end of the second switch tube is connected to the first end of the driving transistor at a second node, and the second end of the first capacitor and the first end of the second capacitor are connected to the second end of the driving transistor at a third node for compensating the threshold voltage of the driving transistor; the first end of the input switch tube receives a data voltage corresponding to grayscale data, and the second end of the input switch tube is connected to the control end of the driving transistor for increasing the data voltage to the driving transistor.

[0012] In a possible implementation, the pixel compensation circuit also includes a reset module, which includes a third switch tube and a fourth switch tube, the control end of the third switch tube is connected to the control end of the fourth switch tube, the first end of the third switch tube is connected to the second end of the second capacitor for receiving a first input voltage, the second end of the third switch tube is connected to the third node, and is used to provide the first input voltage to the second end of the driving transistor and the first end of the second capacitor, the first end of the fourth switch tube is used to receive the second input voltage, and the second end of the fourth switch tube is connected to the fourth node, and is used to provide the second input voltage to the light-emitting device.

[0013] In a possible implementation, the driving module also includes a fifth switch tube and a sixth switch tube, the first end of the fifth switch tube receives the power supply voltage, the second end of the fifth switch tube is connected to the second node, the first end of the sixth switch tube is connected to the third node, and the second end of the sixth switch tube is connected to the fourth node.

[0014] In a possible implementation, the working cycle of the pixel compensation circuit includes: in a reset stage, the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, and the driving transistor are turned on, and the reset module is configured to control the second end of the driving transistor to receive the first input voltage, and control the input end of the light-emitting device to receive the second input voltage; the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, so that the voltage difference between the gate and the source of the driving transistor is a preset value; in a voltage compensation stage, the first switch tube, the second switch tube, and the driving transistor are turned on, and the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, and control the second switch tube and the driving transistor to receive the reference voltage. The body tube charges the third node until the third node voltage becomes the difference between the reference voltage and the threshold voltage; in the writing stage, the input switch tube is turned on, the data voltage is transmitted to the control end of the driving transistor, and the third node voltage becomes a writing voltage determined based on the reference voltage, the threshold voltage, the data voltage, the first capacitor and the second capacitor; in the light-emitting stage, the fifth switch tube, the sixth switch tube and the driving transistor are turned on, the first node voltage is a first sum voltage of the data voltage and the offset voltage, the third node voltage is a second sum voltage of the write voltage and the offset voltage, and the light-emitting device generates an effective brightness corresponding to the data voltage according to the driving current in the light-emitting stage, and the offset voltage is the voltage change caused by the turning on of the driving transistor.

[0015] In one possible implementation, the working cycle of the pixel compensation circuit also includes: in the bias compensation stage, the second switch tube is turned on, and the compensation module is configured to control the first end of the driving transistor to receive the reference voltage so that the voltage difference between the gate and the source of the driving transistor is the difference between the first sum voltage and the reference voltage.

[0016] In a possible implementation, the driving transistor, the input switch tube, and the first switch tube are N-type channel thin film transistors, and the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, and the sixth switch tube are N-type channel thin film transistors or P-type channel thin film transistors.

[0017] According to another aspect of the present disclosure, a pixel circuit is provided, comprising a light emitting device and the pixel compensation circuit as described above, wherein the pixel compensation circuit is connected to the light emitting device.

[0018] According to another aspect of the present disclosure, a display panel is provided, comprising the pixel circuit as described above, wherein the display panel is at least one of a micro light emitting diode display panel, a light emitting diode display panel, a mini light emitting diode display panel, a quantum dot light emitting diode display panel, an organic light emitting diode display panel, a cathode ray tube display panel, a digital light processing display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel, an electrowetting display panel and a small pitch display panel.

[0019] According to another aspect of the present disclosure, an electronic device is provided, comprising the display panel as described above.

[0020] According to another aspect of the present disclosure, a chip is provided, comprising the pixel compensation circuit as described above.

[0021] The pixel compensation circuit of the embodiment of the present disclosure is used to drive a light-emitting device, and the pixel compensation circuit includes: a driving module, the driving module includes a driving transistor, the control end of the driving transistor receives a first node voltage, the first end of the driving transistor receives a second node voltage, the second end of the driving transistor receives a third node voltage and provides a driving current to the light-emitting device; a compensation module, the compensation module includes a first capacitor, a second capacitor, a first switch tube, and a second switch tube, the first end of the first switch tube and the first end of the second switch tube are used to input a reference voltage, the second end of the first switch tube and the first end of the first capacitor are connected to the control end of the driving transistor at a first node, the second end of the second switch tube is connected to the first end of the driving transistor at a second node, and the second end of the first capacitor and the first end of the second capacitor are connected to the second end of the driving transistor at a third node; an input module, the input module includes an input switch tube, the first end of the input switch tube receives a data voltage corresponding to grayscale data, and the second end of the input switch tube is connected to the control end of the driving transistor.

[0022] Through the pixel compensation circuit of the embodiment of the present disclosure, the threshold voltage of the driving transistor can be compensated, and the uneven display phenomenon caused by inconsistent threshold voltages of the driving transistor can be improved. At the same time, the pixel compensation circuit can improve the short-term afterimage of the light-emitting device during the initialization stage.

[0023] Further features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the disclosure and, together with the description, serve to explain the principles of the disclosure.

[0025] Figure 1 A schematic diagram of a pixel compensation circuit according to an embodiment of the present disclosure is shown.

[0026] Figure 2 A signal timing diagram of a pixel compensation circuit according to an embodiment of the present disclosure is shown.

[0027] Figure 3 FIG. 4 is a schematic diagram showing the operation of a pixel compensation circuit in a reset phase according to an embodiment of the present disclosure.

[0028] Figure 4 A schematic diagram showing the operation of a pixel compensation circuit in a voltage compensation stage according to an embodiment of the present disclosure is shown.

[0029] Figure 5 FIG. 4 is a schematic diagram showing the operation of a pixel compensation circuit in a writing phase according to an embodiment of the present disclosure.

[0030] Figure 6 A schematic diagram showing the operation of a pixel compensation circuit in a light emitting stage according to an embodiment of the present disclosure is shown.

[0031] Figure 7 A schematic diagram showing the operation of a pixel compensation circuit in a bias compensation stage according to an embodiment of the present disclosure is shown.

[0032] Figure 8 A schematic diagram showing another pixel compensation circuit according to an embodiment of the present disclosure is shown.

[0033] Fig. 9 Another signal timing diagram of a pixel compensation circuit according to an embodiment of the present disclosure is shown.

[0034] Fig.10 A flowchart of a pixel supplementation method according to an embodiment of the present disclosure is shown.

[0035] Fig.11 A block diagram of an electronic device according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0036] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0037] In the description of the present disclosure, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0039] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0040] It should be understood that in the following description, a "circuit" may include a single or multiple combined hardware circuits, programmable circuits, state machine circuits, and / or elements capable of storing instructions executed by programmable circuits. When an element or circuit is said to be "connected to" another element or an element or circuit is said to be "connected between" two nodes, it may be directly coupled or connected to another element or there may be an intermediate element, and the connection between the elements may be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there is no intermediate element between the two.

[0041] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0042] Figure 1FIG. 1 is a schematic diagram showing a pixel compensation circuit according to an embodiment of the present disclosure. Figure 1 As shown, the pixel compensation circuit is used to drive the light emitting device OLED, and the pixel compensation circuit includes:

[0043] The driving module 10 includes a driving transistor M4, a control terminal of the driving transistor M4 receives a voltage of a first node N1 (see Figure 1 The first end of the driving transistor M4 receives the voltage of the second node N2 (see Figure 1 The second end of the driving transistor M4 receives the voltage of the third node N3 (see Figure 1 and providing a driving current to the light emitting device OLED;

[0044] Optionally, the driving module M4 further includes a fifth switch tube M3 and a sixth switch tube M7, wherein a first end of the fifth switch tube M3 receives a power supply voltage ELVDD, a second end of the fifth switch tube M3 is connected to the second node N2, a first end of the sixth switch tube M7 is connected to the third node N3, and a second end of the sixth switch tube M7 is connected to the fourth node N4. The control end of the fifth switch tube M3 and the control end of the sixth switch tube M7 both receive a fifth control signal EM.

[0045] The compensation module 20 includes a first capacitor C1, a second capacitor C2, a first switch tube M1, and a second switch tube M2. The first end of the first switch tube M1 and the first end of the second switch tube M2 are used to input a reference voltage VREF. The second end of the first switch tube M1 and the first end of the first capacitor C1 are connected to the control end of the driving transistor M4 at a first node N1. The second end of the second switch tube M2 is connected to the first end of the driving transistor M4 at a second node N2. The second end of the first capacitor C1 and the first end of the second capacitor C2 are connected to the second end of the driving transistor M4 at a third node N3. The control end of the first switch tube M1 receives a first control signal S1, and the control end of the second switch tube M2 receives a fourth control signal S4.

[0046] The input module 30 includes an input switch tube M5, a first end of the input switch tube M5 receives a data voltage Vdata corresponding to grayscale data, a second end of the input switch tube M5 is connected to the control end of the driving transistor M4, and the control end of the input switch tube M5 receives a third control signal S3.

[0047] Optional, such as Figure 1As shown, the pixel compensation circuit further includes a reset module 40, the reset module 40 includes a third switch tube M6 and a fourth switch tube M8, the control end of the third switch tube M6 is connected to the control end of the fourth switch tube M8, the control end of the third switch tube M6 and the control end of the fourth switch tube M8 both receive the second control signal S2, the first end of the third switch tube M6 is connected to the second end of the second capacitor C2 for receiving the first input voltage Vint1, the second end of the third switch tube M6 is connected to the third node N3, for providing the first input voltage Vint1 to the second end of the driving transistor M4 and the first end of the second capacitor C2, the first end of the fourth switch tube M8 is used to receive the second input voltage Vint2, the second end of the fourth switch tube M8 is connected to the fourth node N4, for providing the second input voltage Vint2 to the light emitting device OLED. Wherein, the anode of the light emitting device OLED is connected to the fourth node N4, and the cathode of the light emitting device OLED receives the common ground terminal voltage ELVSS, and the common ground terminal voltage ELVSS is opposite to the power supply voltage ELVDD.

[0048] In this way, the threshold voltage Vth of the driving transistor M4 can be compensated, and the uneven display phenomenon caused by the inconsistent threshold voltage Vth of the driving transistor M4 can be improved. At the same time, the pixel compensation circuit can improve the short-term afterimage of the light-emitting device OLED during the initialization stage.

[0049] In a possible implementation, the light-emitting device OLED has a turn-on voltage, and emits light when the voltage difference between the anode and cathode of the light-emitting device OLED is greater than or equal to the turn-on voltage. In a specific implementation, the anode of the light-emitting device OLED is electrically connected to the pixel compensation circuit. In an embodiment of the present disclosure, the light-emitting device may include: an electroluminescent diode, for example: an organic light-emitting diode (OLED), a quantum dot light-emitting diode (QLED).

[0050] In a possible implementation, the pixel compensation circuit and the light-emitting device may be configured in a display area of ​​the display panel, so that the display panel can display images.

[0051] In a possible implementation, the pixel compensation circuit can be configured in the non-display area of ​​the display panel, which can reduce the space occupied by the display area. The pixel compensation circuit can be located in the non-display area of ​​the substrate of the display panel surrounding the display area. Alternatively, the pixel compensation circuit can also be in at least one of a driver chip, a flexible circuit board, and a printed circuit board in the display panel.

[0052] In a possible implementation, the driving transistor M4, the input switch tube M5, and the first switch tube M1 are N-channel thin film transistors, and the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the fifth switch tube M3, and the sixth switch tube M7 are N-channel thin film transistors or P-channel thin film transistors.

[0053] The gate of the driving transistor M4 may be used as the control terminal, the drain of the driving transistor M4 may be used as the first terminal, and the source of the driving transistor M4 may be used as the second terminal.

[0054] For the input switch tube M5, the first switch tube M1, the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the fifth switch tube M3, and the sixth switch tube M7, the control end of these switch tubes is the gate, the first end can be the source, and the second end can be the drain; or, the first end can be the drain, and the second end can be the source, and no specific distinction is made here. Further, in a specific implementation, the N-type switch tube is turned on under the action of a high-level signal and is turned off under the action of a low-level signal. The P-type switch tube is turned off under the action of a high-level signal and is turned on under the action of a low-level signal.

[0055] Since the driving transistor M4, the input switch tube M5, and the first switch tube M1 are all N-type channel thin film transistors, and the channel types of the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the fifth switch tube M3, and the sixth switch tube M7 are the same, all of which are N-type or P-type, it can be ensured that the storage capacitor (for example, including the first capacitor C1 and the second capacitor C2) in the pixel compensation circuit stably maintains the voltage value in the writing stage.

[0056] Furthermore, since the pixel compensation circuit is composed of thin film transistors, the thin film transistors have a stable ultra-low leakage current. During the entire light-emitting stage, the data voltage Vdata can be stably stored in the first node N1, which can meet the application requirements of low refresh rates such as 1Hz (refreshed once per second) or even lower than 0.1Hz (refreshed once per 10 seconds).

[0057] The above is only an example to illustrate the specific structure of the pixel compensation circuit provided in the embodiment of the present disclosure. In specific implementation, the specific structure of the above pixel compensation circuit is not limited to the above structure provided in the embodiment of the present disclosure, and can be adjusted according to the actual application scenario, which is not limited here.

[0058] Assume that Figure 1For example, the driving transistor M4, the input switch tube M5, the first switch tube M1, the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the fifth switch tube M3, and the sixth switch tube M7 are N-channel thin film transistors. Figure 2 A signal timing diagram of a pixel compensation circuit according to an embodiment of the present disclosure is shown as follows: Figure 2 As shown, the working cycle of the pixel compensation circuit can be divided into five stages, namely, a reset stage, a voltage compensation stage, a write stage, a light emitting stage and a bias compensation stage, corresponding to Figure 2 The T1, T2, T3, T4 and T5 time periods.

[0059] It should be noted that the high-level signal and the low-level signal in the following description are logic levels, which are only for better explaining the specific working process of the embodiment of the present disclosure. The present disclosure does not limit the voltage applied to the gate of each transistor during the specific implementation.

[0060] Figure 3 FIG. 4 is a schematic diagram showing the operation of the pixel compensation circuit in the reset phase according to an embodiment of the present disclosure. Figure 3 As shown, in the reset stage, the reference voltage VREF, the first control signal S1 received by the control end of the first switch tube M1, the fourth control signal S4 received by the control end of the second switch tube M2, and the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8 are at a high level; the third control signal S3 received by the control end of the input switch tube M5, and the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7 are at a low level.

[0061] In this case, the first switch tube M1, the second switch tube M2, the third switch tube M6, the fourth switch tube M8, and the driving transistor M4 can be controlled to be turned on; the input switch tube M5, the fifth switch tube M3, and the sixth switch tube M7 can be controlled to be turned off. The reset module 40 is configured to control the second end of the driving transistor M4 to receive the first input voltage Vint1, and control the input end of the light-emitting device OLED to receive the second input voltage Vint2; the compensation module 20 is configured to control the first end and the control end of the driving transistor M4 to receive the reference voltage VREF, so that the voltage difference between the gate and the source of the driving transistor M4 is a preset value.

[0062] Exemplarily, the reference voltage VREF is transmitted to the second node N2 and the first node N1 respectively through the second switch tube M2 and the first switch tube M1; the first input voltage Vint1 is transmitted to the third node N3 through the third switch tube M6; the second input voltage Vint2 is transmitted to the fourth node N4 through the fourth switch tube M8; this process can complete the reset of the first capacitor C1 and the second capacitor C2; at this time, the reference voltage VREF is greater than the first input voltage Vint1, and the voltage difference Vgs between the gate and the source of the driving transistor M4 in the pixel compensation circuit is a preset value, that is: Vgs = VREF-Vint1, where VREF-Vint1 is a fixed voltage, which can improve the short-term residual image of the light-emitting device OLED. At the same time, the second input voltage Vint2 can be transmitted to the fourth node N4 to complete the reset of the anode of the light-emitting device OLED, and the voltages of each node are shown in Table 1:

[0063] Table 1

[0064] node Voltage The first node N1 VREF The second node N2 VREF The third node N3 Vint1 Fourth node N4 Vint2

[0065] Figure 4 FIG. 4 is a schematic diagram showing the operation of a pixel compensation circuit in a voltage compensation stage according to an embodiment of the present disclosure. Figure 4 As shown, in the voltage compensation stage, the reference voltage VREF, the first control signal S1 received by the control end of the first switch tube M1, and the fourth control signal S4 received by the control end of the second switch tube M2 are high level; the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8, the third control signal S3 received by the control end of the input switch tube M5, and the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7 are low level.

[0066] In this case, the first switch tube M1, the second switch tube M2, and the driving transistor M4 can be controlled to be turned on; the input switch tube M5, the fifth switch tube M3, the third switch tube M6, the fourth switch tube M8, and the sixth switch tube M7 can be controlled to be turned off. The compensation module 20 is configured to control the first end and the control end of the driving transistor M4 to receive the reference voltage VREF, and charge the third node N3 through the second switch tube M2 and the driving transistor M4 until the voltage of the third node N3 becomes the difference between the reference voltage VREF and the threshold voltage Vth, that is, VREF-Vth, and the charging can be stopped. At this stage, the purpose of compensating the threshold voltage Vth of the driving transistor M4 is completed. The voltages of each node are shown in Table 2:

[0067] Table 2

[0068] node Voltage The first node N1 VREF The second node N2 VREF The third node N3 VREF-Vth

[0069] Figure 5FIG. 4 is a schematic diagram showing the operation of a pixel compensation circuit in a writing phase according to an embodiment of the present disclosure. Figure 5 As shown, in the writing stage, the reference voltage VREF and the third control signal S3 received by the control end of the input switch tube M5 are at a high level; the first control signal S1 received by the control end of the first switch tube M1, the fourth control signal S4 received by the control end of the second switch tube M2, the second control signal S2 received by the control ends of the third switch tube M6 and the fourth switch tube M8, and the fifth control signal EM received by the control ends of the fifth switch tube M3 and the sixth switch tube M7 are at a low level.

[0070] In this case, the input switch tube M5 can be controlled to be turned on, and the first switch tube M1, the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the driving transistor M4, the fifth switch tube M3, and the sixth switch tube M7 can be controlled to be turned off. The data voltage Vdata is transmitted to the control end of the driving transistor M4, and the voltage of the third node N3 becomes a write voltage determined based on the reference voltage VREF, the threshold voltage Vth, the data voltage Vdata, the first capacitor C1, and the second capacitor C2, for example: VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)].

[0071] Exemplarily, the data voltage Vdata is transmitted to the first node N1 through the input switch tube M5, and the voltage of the first node N1 changes from the previous reference voltage VREF to the data voltage Vdata. Due to the characteristics of the capacitor (for example, the voltage across the capacitor will not change suddenly), the third node voltage is coupled to VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)], as shown in Table 3:

[0072] Table 3

[0073] node Voltage The first node N1 Vdata The third node N3 VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]

[0074] It can be seen from the above embodiments that the present disclosure can prevent the light-emitting device OLED from emitting light during the initialization stage (for example, including the reset stage T1, the voltage compensation stage T2, and the writing stage T3) through the structure of a simple pixel compensation circuit, thereby improving the short-term afterimage problem of the light-emitting device OLED.

[0075] Figure 6 FIG. 4 is a schematic diagram showing the operation of a pixel compensation circuit in a light emitting stage according to an embodiment of the present disclosure. Figure 6As shown, in the light-emitting stage, the reference voltage VREF, the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7 are at a high level; the third control signal S3 received by the control end of the input switch tube M5, the first control signal S1 received by the control end of the first switch tube M1, the fourth control signal S4 received by the control end of the second switch tube M2, and the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8 are at a low level.

[0076] In this case, the driving transistor M4, the fifth switch tube M3, and the sixth switch tube M7 can be controlled to be turned on; the input switch tube M5, the first switch tube M1, the second switch tube M2, the third switch tube M6, and the fourth switch tube M8 can be controlled to be turned off, and the light-emitting device OLED completes emitting light. According to the transistor saturation region current formula, that is:

[0077] I OLED ∝(Vgs-Vth) 2

[0078] I OLED ∝[Vdata+△V-(VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]+△V)-Vth] 2

[0079] I OLED ∝WC ox u / 2L×{(Vdata-VREF)×[C2 / (C1+C2)]} 2

[0080] Among them, I OLED represents the driving current flowing to the light emitting device OLED, ∝ represents proportional to, Vgs represents the voltage difference between the gate and the source of the driving transistor M4 in the pixel compensation circuit, △V represents the offset voltage caused by the driving transistor M4 being turned on, VREF represents the reference voltage, C1 represents the capacitance value of the first capacitor, C2 represents the capacitance value of the second capacitor, u represents the carrier mobility, W represents the channel width of the driving transistor M4, L represents the channel length of the driving transistor M4, C ox is the control terminal capacitance of the driving transistor M4 per unit area, Vth is the threshold voltage of the driving transistor M4, Vdata is the data voltage, W and L are fixed in the design, C ox Depends on the thickness and material of the control end insulation layer.

[0081] It can be seen from this that the driving current I of the light-emitting device OLED OLEDThe equivalent formula has nothing to do with the power supply voltage ELVDD, and can improve the phenomenon of uneven display at different positions of the screen caused by panel IR Drop (for example, a DC voltage drop generated during the transmission of the power supply voltage ELVDD).

[0082] In addition, due to the process and device aging, the threshold voltage Vth of the driving transistor M4 may drift, which results in the driving current I flowing through each light emitting device OLED. OLED Affected by the drift of the threshold voltage Vth, changes occur, resulting in uneven display brightness, thereby affecting the display effect of the entire image.

[0083] Through the above driving current I OLED The formula satisfied shows that the driving current I OLED It is related to the data voltage Vdata of the data signal inputted from the data signal terminal and the reference voltage VREF, but has nothing to do with the threshold voltage Vth of the driving transistor M4. It can solve the problem of the threshold voltage Vth drift caused by the process of the driving transistor M4 and long-term operation on the driving current I OLED The influence of the driving current I OLED Keep stable, thus ensuring the normal operation of the light-emitting device OLED.

[0084] The voltage of each node is shown in Table 4:

[0085] Table 4

[0086] node Voltage The first node N1 Vdata+△V The second node N2 ELVDD The third node N3 VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]+△V

[0087] Among them, the voltage of the first node N1 is the first sum voltage of the data voltage Vdata and the offset voltage △V, that is: Vdata+△V, the voltage of the third node N3 is the second sum voltage of the write voltage VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)] and the offset voltage △V, that is: VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]+△V, the light-emitting device OLED generates an effective brightness corresponding to the data voltage according to the driving current in the light-emitting stage, and the offset voltage △V is the voltage change caused by the conduction of the driving transistor M4.

[0088] Figure 7 FIG. 2 is a schematic diagram showing the operation of a pixel compensation circuit in a bias compensation stage according to an embodiment of the present disclosure. Figure 7As shown, in the bias compensation stage, the fourth control signal S4 received by the control end of the second switch tube M2 is high level; the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7, the reference voltage VREF, the third control signal S3 received by the control end of the input switch tube M5, the first control signal S1 received by the control end of the first switch tube M1, and the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8 are low level. Among them, the low level of the reference voltage VREF can be marked as VREF_skip.

[0089] In this case, the second switch tube M2 can be controlled to be turned on, and the driving transistor M4, the fifth switch tube M3, the sixth switch tube M7, the input switch tube M5, the first switch tube M1, the third switch tube M6, and the fourth switch tube M8 can be controlled to be turned off. The compensation module 20 is configured to control the first end of the driving transistor M4 to receive the reference voltage VREF_skip, so that the voltage difference between the gate and the source of the driving transistor M4 is the difference between the first sum voltage Vdata+ΔV and the reference voltage VREF_skip.

[0090] For example, the reference voltage VREF_skip is transmitted to the second node N2 through the second switch tube M2. In the bias compensation stage, since the data voltage Vdata is not updated, the driving transistor M4 is driven by the forward bias of the voltage difference Vgs between the gate and the source of the driving transistor M4 for a long time in the bias compensation stage, which causes the threshold voltage Vth of the fifth switch tube M3 to shift, thus causing the light emitting brightness of the light emitting device OLED to change in the bias compensation stage.

[0091] In order to improve this phenomenon, in the bias compensation stage, the low level VREF_skip of the reference voltage is adjusted to a smaller voltage to ensure that the low level VREF_skip of the reference voltage is less than the voltage V N3 At this time, the source of the driving transistor M4 changes to the second node N2, Vgs=Vdata+ΔV-VREF_skip, and during the time when the fifth control signal EM is at a low level (non-luminous), multiple driving bias compensation actions for the driving transistor M4 are completed, which can improve the forward pressure that the driving transistor M4 is subjected to for a long time, thereby improving the threshold voltage vth voltage drift phenomenon.

[0092] The voltage of each node is shown in Table 5:

[0093] Table 5

[0094] node Voltage The first node N1 Vdata+△V The second node N2 VREF_skip

[0095] Figure 8FIG. 2 is a schematic diagram showing another pixel compensation circuit according to an embodiment of the present disclosure. Figure 8 As shown, the driving transistor M4, the input switch tube M5, and the first switch tube M1 are N-type channel thin film transistors, and the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the fifth switch tube M3, and the sixth switch tube M7 are P-type channel thin film transistors. Fig. 9 Another signal timing diagram of a pixel compensation circuit according to an embodiment of the present disclosure is shown as follows: Fig. 9 As shown, the working cycle of the pixel compensation circuit can be divided into five stages, namely, a reset stage, a voltage compensation stage, a write stage, a light emitting stage and a bias compensation stage, corresponding to Figure 2 The T1, T2, T3, T4 and T5 time periods.

[0096] In the reset stage, the reference voltage VREF, the first control signal S1 received by the control end of the first switch tube M1, and the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7 are at a high level; the fourth control signal S4 received by the control end of the second switch tube M2, the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8, and the third control signal S3 received by the control end of the input switch tube M5 are at a low level.

[0097] In this case, the first switch tube M1, the second switch tube M2, the third switch tube M6, the fourth switch tube M8, and the driving transistor M4 can be controlled to be turned on; the input switch tube M5, the fifth switch tube M3, and the sixth switch tube M7 can be controlled to be turned off. The reset module 40 is configured to control the second end of the driving transistor M4 to receive the first input voltage Vint1, and control the input end of the light-emitting device OLED to receive the second input voltage Vint2; the compensation module 20 is configured to control the first end and the control end of the driving transistor M4 to receive the reference voltage VREF, so that the voltage difference between the gate and the source of the driving transistor M4 is a preset value.

[0098] Exemplarily, the reference voltage VREF is transmitted to the second node N2 and the first node N1 respectively through the second switch tube M2 and the first switch tube M1; the first input voltage Vint1 is transmitted to the third node N3 through the third switch tube M6; the second input voltage Vint2 is transmitted to the fourth node N4 through the fourth switch tube M8; this process can complete the reset of the first capacitor C1 and the second capacitor C2; at this time, the reference voltage VREF is greater than the first input voltage Vint1, and the voltage difference Vgs between the gate and the source of the driving transistor M4 in the pixel compensation circuit is a preset value, that is: Vgs = VREF-Vint1, where VREF-Vint1 is a fixed voltage, which can improve the short-term residual image of the light-emitting device OLED. At the same time, the second input voltage Vint2 can be transmitted to the fourth node N4 to complete the reset of the anode of the light-emitting device OLED, and the voltages of each node are shown in Table 6:

[0099] Table 6

[0100] node Voltage The first node N1 VREF The second node N2 VREF The third node N3 Vint1 Fourth node N4 Vint2

[0101] In the voltage compensation stage, the reference voltage VREF, the first control signal S1 received by the control end of the first switch tube M1, the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8, and the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7 are at a high level; the fourth control signal S4 received by the control end of the second switch tube M2 and the third control signal S3 received by the control end of the input switch tube M5 are at a low level.

[0102] In this case, the first switch tube M1, the second switch tube M2, and the driving transistor M4 can be controlled to be turned on; the input switch tube M5, the fifth switch tube M3, the third switch tube M6, the fourth switch tube M8, and the sixth switch tube M7 can be controlled to be turned off. The compensation module 20 is configured to control the first end and the control end of the driving transistor M4 to receive the reference voltage VREF, and charge the third node N3 through the second switch tube M2 and the driving transistor M4 until the voltage of the third node N3 becomes the difference between the reference voltage VREF and the threshold voltage Vth, that is, VREF-Vth, and the charging can be stopped. At this stage, the purpose of compensating the threshold voltage Vth of the driving transistor M4 is completed. The voltages of each node are shown in Table 7:

[0103] Table 7

[0104] node Voltage The first node N1 VREF The second node N2 VREF The third node N3 VREF-Vth

[0105] In the writing stage, the first control signal S1 received by the control end of the first switch tube M1 is at a low level; the reference voltage VREF, the third control signal S3 received by the control end of the input switch tube M5, the fourth control signal S4 received by the control end of the second switch tube M2, the second control signal S2 received by the control ends of the third switch tube M6 and the fourth switch tube M8, and the fifth control signal EM received by the control ends of the fifth switch tube M3 and the sixth switch tube M7 are at a high level.

[0106] In this case, the input switch tube M5 can be controlled to be turned on, and the first switch tube M1, the second switch tube M2, the third switch tube M6, the fourth switch tube M8, the driving transistor M4, the fifth switch tube M3, and the sixth switch tube M7 can be controlled to be turned off. The data voltage Vdata is transmitted to the control end of the driving transistor M4, and the voltage of the third node N3 becomes a write voltage determined based on the reference voltage VREF, the threshold voltage Vth, the data voltage Vdata, the first capacitor C1, and the second capacitor C2, for example: VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)].

[0107] Exemplarily, the data voltage Vdata is transmitted to the first node N1 through the input switch tube M5, and the voltage of the first node N1 changes from the previous reference voltage VREF to the data voltage Vdata. Due to the characteristics of the capacitor (for example, the voltage across the capacitor will not change suddenly), the third node voltage is coupled to VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)], as shown in Table 8:

[0108] Table 8

[0109] node Voltage The first node N1 Vdata The third node N3 VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]

[0110] It can be seen from the above embodiments that the present disclosure can prevent the light-emitting device OLED from emitting light during the initialization stage (for example, including the reset stage T1, the voltage compensation stage T2, and the writing stage T3) through the structure of a simple pixel compensation circuit, thereby improving the short-term afterimage problem of the light-emitting device OLED.

[0111] In the light-emitting stage, the reference voltage VREF, the fourth control signal S4 received by the control end of the second switch tube M2, and the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8 are at a high level; the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7, the third control signal S3 received by the control end of the input switch tube M5, and the first control signal S1 received by the control end of the first switch tube M1 are at a low level.

[0112] In this case, the driving transistor M4, the fifth switch tube M3, and the sixth switch tube M7 can be controlled to be turned on; the input switch tube M5, the first switch tube M1, the second switch tube M2, the third switch tube M6, and the fourth switch tube M8 can be controlled to be turned off, and the light-emitting device OLED completes emitting light. According to the transistor saturation region current formula, that is:

[0113] I OLED ∝(Vgs-Vth) 2

[0114] I OLED ∝[Vdata+△V-(VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]+△V)-Vth] 2

[0115] I OLED ∝WC ox u / 2L×{(Vdata-VREF)×[C2 / (C1+C2)]} 2

[0116] Among them, I OLED represents the driving current flowing to the light emitting device OLED, ∝ represents proportional to, Vgs represents the voltage difference between the gate and the source of the driving transistor M4 in the pixel compensation circuit, △V represents the offset voltage caused by the turning on of the driving transistor M4, VREF represents the reference voltage, C1 represents the first capacitor, C2 represents the second capacitor, u represents the carrier mobility, W represents the channel width of the driving transistor M4, L represents the channel length of the driving transistor M4, C ox is the control terminal capacitance of the driving transistor M4 per unit area, Vth is the threshold voltage of the driving transistor M4, Vdata is the data voltage, W and L are fixed in the design, C ox Depends on the thickness and material of the control end insulation layer.

[0117] It can be seen from this that the driving current I of the light-emitting device OLED OLED The equivalent formula has nothing to do with the power supply voltage ELVDD, and can improve the phenomenon of uneven display at different positions of the screen caused by panel IR Drop (for example, a DC voltage drop generated during the transmission of the power supply voltage ELVDD).

[0118] In addition, due to the process and device aging, the threshold voltage Vth of the driving transistor M4 may drift, which results in the driving current I flowing through each light emitting device OLED. OLED Affected by the drift of the threshold voltage Vth, the change causes uneven display brightness, thereby affecting the display effect of the entire image. OLED The formula satisfied shows that the driving current IOLED It is related to the data voltage Vdata of the data signal inputted from the data signal terminal and the reference voltage VREF, but has nothing to do with the threshold voltage Vth of the driving transistor M4. It can solve the problem of the threshold voltage Vth drift caused by the process of the driving transistor M4 and long-term operation on the driving current I OLED The influence of the driving current I OLED Keep stable, thus ensuring the normal operation of the light-emitting device OLED.

[0119] The voltage of each node is shown in Table 9:

[0120] Table 9

[0121] node Voltage The first node N1 Vdata+△V The second node N2 ELVDD The third node N3 VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]+△V

[0122] Among them, the voltage of the first node N1 is the first sum voltage of the data voltage Vdata and the offset voltage △V, that is: Vdata+△V, the voltage of the third node N3 is the second sum voltage of the write voltage VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)] and the offset voltage △V, that is: VREF-Vth+(Vdata-VREF)×[C1 / (C1+C2)]+△V, the light-emitting device OLED generates an effective brightness corresponding to the data voltage according to the driving current in the light-emitting stage, and the offset voltage △V is the voltage change caused by the conduction of the driving transistor M4.

[0123] In the bias compensation stage, the fifth control signal EM received by the control end of the fifth switch tube M3 and the control end of the sixth switch tube M7, and the second control signal S2 received by the control end of the third switch tube M6 and the control end of the fourth switch tube M8 are high level; the fourth control signal S4 received by the control end of the second switch tube M2, the reference voltage VREF, the third control signal S3 received by the control end of the input switch tube M5, and the first control signal S1 received by the control end of the first switch tube M1 are low level. The low level of the reference voltage VREF can be marked as VREF_skip.

[0124] In this case, the second switch tube M2 can be controlled to be turned on, and the driving transistor M4, the fifth switch tube M3, the sixth switch tube M7, the input switch tube M5, the first switch tube M1, the third switch tube M6, and the fourth switch tube M8 can be controlled to be turned off. The compensation module 20 is configured to control the first end of the driving transistor M4 to receive the reference voltage VREF_skip, so that the voltage difference between the gate and the source of the driving transistor M4 is the difference between the first sum voltage Vdata+ΔV and the reference voltage VREF_skip.

[0125] For example, the reference voltage VREF_skip is transmitted to the second node N2 through the second switch tube M2. In the bias compensation stage, since the data voltage Vdata is not updated, the driving transistor M4 is driven by the forward bias of the voltage difference Vgs between the gate and the source of the driving transistor M4 for a long time in the bias compensation stage, which causes the threshold voltage Vth of the fifth switch tube M3 to shift, thus causing the light emitting brightness of the light emitting device OLED to change in the bias compensation stage.

[0126] In order to improve this phenomenon, in the bias compensation stage, the low level VREF_skip of the reference voltage is adjusted to a smaller voltage to ensure that the low level VREF_skip of the reference voltage is less than the voltage V N3 At this time, the source of the driving transistor M4 changes to the second node N2, Vgs=Vdata+ΔV-VREF_skip, and during the time when the fifth control signal EM is at a low level (non-luminous), multiple driving bias compensation actions for the driving transistor M4 are completed, which can improve the forward pressure that the driving transistor M4 is subjected to for a long time, thereby improving the threshold voltage vth voltage drift phenomenon.

[0127] The voltages of each node are shown in Table 10:

[0128] Table 10

[0129] node Voltage The first node N1 Vdata+△V The second node N2 VREF_skip

[0130] In summary, the embodiment of the present disclosure can compensate for the threshold voltage Vth of the driving transistor M4 in the pixel circuit, so that the storage capacitor (such as the first capacitor C1 and the second capacitor C2) in the pixel circuit can stably maintain the data voltage Vdata in the writing stage, and can be applied to low refresh rates such as 1Hz (refresh once per second) or even lower 0.1Hz (refresh once per 10 seconds). In addition, the pixel compensation circuit of the embodiment of the present disclosure provides the driving current I OLED The equivalent formula is independent of the power supply voltage ELVDD and the threshold voltage Vth, and can improve the phenomenon of uneven display at different positions of the screen caused by panel IR Drop (eg, a DC voltage drop generated during the transmission of the power supply voltage ELVDD).

[0131] Fig.10 FIG. 2 is a flowchart of a pixel supplementation method according to an embodiment of the present disclosure. Fig.10As shown, the pixel compensation method is applied to a pixel compensation circuit, the pixel compensation circuit includes a driving module, a compensation module, and an input module, the driving module includes a driving transistor, the compensation module includes a first capacitor, a second capacitor, a first switch tube, and a second switch tube, and the input module includes an input switch tube; the pixel compensation method is used to drive a light-emitting device, and the pixel compensation method includes:

[0132] In step S11, the control terminal of the driving transistor receives a first node voltage, the first terminal of the driving transistor receives a second node voltage, the second terminal of the driving transistor receives a third node voltage and provides a driving current to the light emitting device;

[0133] In step S12, the first end of the first switch tube and the first end of the second switch tube are used to input a reference voltage, the second end of the first switch tube and the first end of the first capacitor are connected to the control end of the driving transistor at a first node, the second end of the second switch tube is connected to the first end of the driving transistor at a second node, and the second end of the first capacitor and the first end of the second capacitor are connected to the second end of the driving transistor at a third node, for compensating for the threshold voltage of the driving transistor;

[0134] In step S13, the first end of the input switch tube receives a data voltage corresponding to the grayscale data, and the second end of the input switch tube is connected to the control end of the driving transistor to increase the data voltage to the driving transistor.

[0135] In a possible implementation, the pixel compensation circuit also includes a reset module, which includes a third switch tube and a fourth switch tube, the control end of the third switch tube is connected to the control end of the fourth switch tube, the first end of the third switch tube is connected to the second end of the second capacitor for receiving a first input voltage, the second end of the third switch tube is connected to the third node, and is used to provide the first input voltage to the second end of the driving transistor and the first end of the second capacitor, the first end of the fourth switch tube is used to receive the second input voltage, and the second end of the fourth switch tube is connected to the fourth node, and is used to provide the second input voltage to the light-emitting device.

[0136] In a possible implementation, the driving module also includes a fifth switch tube and a sixth switch tube, the first end of the fifth switch tube receives the power supply voltage, the second end of the fifth switch tube is connected to the second node, the first end of the sixth switch tube is connected to the third node, and the second end of the sixth switch tube is connected to the fourth node.

[0137] In a possible implementation, the working cycle of the pixel compensation circuit includes: in a reset stage, the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, and the driving transistor are turned on, and the reset module is configured to control the second end of the driving transistor to receive the first input voltage, and control the input end of the light-emitting device to receive the second input voltage; the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, so that the voltage difference between the gate and the source of the driving transistor is a preset value; in a voltage compensation stage, the first switch tube, the second switch tube, and the driving transistor are turned on, and the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, and control the second switch tube and the driving transistor to receive the reference voltage. The body tube charges the third node until the third node voltage becomes the difference between the reference voltage and the threshold voltage; in the writing stage, the input switch tube is turned on, the data voltage is transmitted to the control end of the driving transistor, and the third node voltage becomes a writing voltage determined based on the reference voltage, the threshold voltage, the data voltage, the first capacitor and the second capacitor; in the light-emitting stage, the fifth switch tube, the sixth switch tube and the driving transistor are turned on, the first node voltage is a first sum voltage of the data voltage and the offset voltage, the third node voltage is a second sum voltage of the write voltage and the offset voltage, and the light-emitting device generates an effective brightness corresponding to the data voltage according to the driving current in the light-emitting stage, and the offset voltage is the voltage change caused by the turning on of the driving transistor.

[0138] In one possible implementation, the working cycle of the pixel compensation circuit also includes: in the bias compensation stage, the second switch tube is turned on, and the compensation module is configured to control the first end of the driving transistor to receive the reference voltage so that the voltage difference between the gate and the source of the driving transistor is the difference between the first sum voltage and the reference voltage.

[0139] In a possible implementation, the driving transistor, the input switch tube, and the first switch tube are N-type channel thin film transistors, and the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, and the sixth switch tube are N-type channel thin film transistors or P-type channel thin film transistors.

[0140] According to another aspect of the present disclosure, a pixel circuit is provided, comprising a light emitting device and the pixel compensation circuit as described above, wherein the pixel compensation circuit is connected to the light emitting device.

[0141] According to another aspect of the present disclosure, a display panel is provided, comprising the pixel circuit as described above, wherein the display panel is at least one of a micro light emitting diode display panel, a light emitting diode display panel, a mini light emitting diode display panel, a quantum dot light emitting diode display panel, an organic light emitting diode display panel, a cathode ray tube display panel, a digital light processing display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel, an electrowetting display panel and a small pitch display panel.

[0142] According to another aspect of the present disclosure, an electronic device is provided, comprising the display panel as described above.

[0143] Exemplarily, the electronic devices in this embodiment include but are not limited to desktop computers, televisions, mobile devices with large screens such as mobile phones, tablet computers, and other common electronic devices that require multiple chips to be cascaded to achieve driving.

[0144] Exemplarily, the electronic device may also be a user equipment (UE), a mobile device, a user terminal, a terminal, a handheld device, a computing device or a vehicle-mounted device, etc. Exemplarily, some examples of terminals are: a display, a smart phone or a portable device, a mobile phone, a tablet computer, a laptop computer, a PDA, a mobile Internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control (Industrial Control), a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid (Smart Grid), a wireless terminal in transportation safety (Transportation Safety), a wireless terminal in smart city (Smart City), a wireless terminal in smart home (Smart Home), a wireless terminal in Internet of Vehicles, etc. For example, the server may be a local server or a cloud server.

[0145] Fig.11 1 is a block diagram of an electronic device 1900 according to an embodiment of the present disclosure. For example, the electronic device 1900 may be provided as a server or a terminal device. Fig.11, the electronic device 1900 includes a processing component 1922, which further includes one or more processors, and a memory resource represented by a memory 1932 for storing instructions executable by the processing component 1922, such as an application. The application stored in the memory 1932 may include one or more modules, each corresponding to a set of instructions. In addition, the processing component 1922 is configured to execute instructions to perform the above method.

[0146] The electronic device 1900 may further include a power supply component 1926 configured to perform power management of the electronic device 1900, a wired or wireless network interface 1950 configured to connect the electronic device 1900 to a network, and an input-output interface 1958. The electronic device 1900 may operate based on an operating system stored in the memory 1932, such as Windows Server™, Mac OS X™, Unix™, Linux™, FreeBSD™ or the like.

[0147] In an exemplary embodiment, a non-volatile computer-readable storage medium is also provided, such as a memory 1932 including computer program instructions, which can be executed by the processing component 1922 of the electronic device 1900 to perform the above method.

[0148] The above description is merely an exemplary embodiment of the present invention and is not intended to limit the protection scope of the present invention. The protection scope of the present invention is determined by the appended claims.

[0149] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0150] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0151] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to multiple embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a part of a module, program segment or instruction, and a part of the module, program segment or instruction includes one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of special hardware and computer instructions.

[0152] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A pixel compensation circuit, characterized in that: The pixel compensation circuit is used to drive the light emitting device, and the pixel compensation circuit includes: A driving module, the driving module comprising a driving transistor, a control terminal of the driving transistor receiving a first node voltage, a first terminal of the driving transistor receiving a second node voltage, a second terminal of the driving transistor receiving a third node voltage and providing a driving current to the light emitting device; A compensation module, the compensation module comprising a first capacitor, a second capacitor, a first switch tube, and a second switch tube, wherein the first end of the first switch tube and the first end of the second switch tube are used to input a reference voltage, the second end of the first switch tube and the first end of the first capacitor are connected to the control end of the driving transistor at a first node, the second end of the second switch tube is connected to the first end of the driving transistor at a second node, and the second end of the first capacitor and the first end of the second capacitor are connected to the second end of the driving transistor at a third node; An input module includes an input switch tube, a first end of the input switch tube receives a data voltage corresponding to grayscale data, and a second end of the input switch tube is connected to the control end of the driving transistor.

2. The pixel compensation circuit according to claim 1, characterized in that: The pixel compensation circuit further includes a reset module, the reset module includes a third switch tube and a fourth switch tube, the control end of the third switch tube is connected to the control end of the fourth switch tube, The first end of the third switch tube is connected to the second end of the second capacitor for receiving a first input voltage, and the second end of the third switch tube is connected to the third node for providing the first input voltage to the second end of the driving transistor and the first end of the second capacitor. The first end of the fourth switch tube is used to receive a second input voltage, and the second end of the fourth switch tube is connected to a fourth node, and is used to provide the second input voltage to the light emitting device.

3. The pixel compensation circuit according to claim 2, characterized in that: The driving module also includes a fifth switch tube and a sixth switch tube, the first end of the fifth switch tube receives the power supply voltage, the second end of the fifth switch tube is connected to the second node, the first end of the sixth switch tube is connected to the third node, and the second end of the sixth switch tube is connected to the fourth node.

4. The pixel compensation circuit according to claim 3, characterized in that: The working cycle of the pixel compensation circuit includes: In the reset stage, the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, and the driving transistor are turned on, and the reset module is configured to control the second end of the driving transistor to receive the first input voltage, and control the input end of the light-emitting device to receive the second input voltage; the compensation module is configured to control the first end and the control end of the driving transistor to receive the reference voltage, so that the voltage difference between the gate and the source of the driving transistor is a preset value; In the voltage compensation stage, the first switch tube, the second switch tube, and the driving transistor are turned on, and the compensation module is configured to control the first terminal and the control terminal of the driving transistor to receive the reference voltage, and charge the third node through the second switch tube and the driving transistor until the voltage of the third node becomes the difference between the reference voltage and the threshold voltage; In the writing phase, the input switch tube is turned on, the data voltage is transmitted to the control end of the driving transistor, and the third node voltage becomes a writing voltage determined based on the reference voltage, the threshold voltage, the data voltage, the first capacitor and the second capacitor; In the light-emitting stage, the fifth switch tube, the sixth switch tube, and the driving transistor are turned on, the first node voltage is a first sum voltage of the data voltage and the offset voltage, the third node voltage is a second sum voltage of the write voltage and the offset voltage, and the light-emitting device generates an effective brightness corresponding to the data voltage according to the driving current in the light-emitting stage, and the offset voltage is the voltage change caused by the turning on of the driving transistor.

5. The pixel compensation circuit according to claim 4, characterized in that: The working cycle of the pixel compensation circuit also includes: In the bias compensation stage, the second switch tube is turned on, and the compensation module is configured to control the first end of the driving transistor to receive the reference voltage so that the voltage difference between the gate and the source of the driving transistor is the difference between the first sum voltage and the reference voltage.

6. The pixel compensation circuit according to any one of claims 3 to 5, characterized in that: The driving transistor, the input switch tube and the first switch tube are N-type channel thin film transistors, and the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube and the sixth switch tube are N-type channel thin film transistors or P-type channel thin film transistors.

7. A pixel circuit, characterized in that: The invention comprises a light emitting device and a pixel compensation circuit as claimed in any one of claims 1 to 6, wherein the pixel compensation circuit is connected to the light emitting device.

8. A display panel, characterized in that: Comprising the pixel circuit according to claim 7, the display panel is at least one of a micro light emitting diode display panel, a light emitting diode display panel, a mini light emitting diode display panel, a quantum dot light emitting diode display panel, an organic light emitting diode display panel, a cathode ray tube display panel, a digital light processing display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel, an electrowetting display panel and a small pitch display panel.

9. An electronic device, characterized in that: Comprising the display panel according to claim 8.

10. A chip, characterized in that: The invention comprises a pixel compensation circuit according to any one of claims 1 to 6.

11. A pixel compensation method, characterized in that: The pixel compensation method is applied to a pixel compensation circuit, the pixel compensation circuit comprises a driving module, a compensation module, and an input module, the driving module comprises a driving transistor, the compensation module comprises a first capacitor, a second capacitor, a first switch tube, and a second switch tube, and the input module comprises an input switch tube; The pixel compensation method is used to drive a light-emitting device, and the pixel compensation method includes: The control terminal of the driving transistor receives a first node voltage, the first terminal of the driving transistor receives a second node voltage, the second terminal of the driving transistor receives a third node voltage and provides a driving current to the light emitting device; The first end of the first switch tube and the first end of the second switch tube are used to input a reference voltage, the second end of the first switch tube and the first end of the first capacitor are connected to the control end of the driving transistor at a first node, the second end of the second switch tube is connected to the first end of the driving transistor at a second node, and the second end of the first capacitor and the first end of the second capacitor are connected to the second end of the driving transistor at a third node, for compensating for a threshold voltage of the driving transistor; The first end of the input switch tube receives a data voltage corresponding to grayscale data, and the second end of the input switch tube is connected to the control end of the driving transistor to increase the data voltage to the driving transistor.

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