OLED pixel circuit, display panel and driving method

Abstract

This application discloses an OLED pixel circuit, a display panel, and a driving method. The OLED pixel circuit includes: a driving module, with a first terminal connected to a power supply voltage and a second terminal providing a driving current; the driving module includes a driving transistor, the control terminal of which receives a driving signal, a first terminal of which is connected to a first node, a second terminal of which has a second node between itself and the power supply voltage, and a fourth node between itself and the driving current, the second terminal of which is selectively connected to the second node and the fourth node; a compensation module for compensating the voltage of the first node, including a first capacitor and a second capacitor, the first terminal of which is connected to the first node and the second terminal of which is connected to a third node, the first terminal of which is connected to the power supply voltage and the second terminal of which is connected to the first node; an input module for providing a data voltage to the third node; and a light-emitting diode connected to the fourth node to receive the driving current.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more specifically, to an OLED pixel circuit, display panel, and driving method. Background Technology

[0002] In the field of display technology, with the advancement of technology and the increasing demand for visualization, displays have become an indispensable part of daily life. However, to ensure that displays can work properly and with high quality, the driving circuit technology behind them is particularly critical.

[0003] OLED (Organic Light-Emitting Diode) is an emerging display device. Due to its advantages such as self-illumination, high contrast, and wide color gamut, as well as its simple manufacturing process, low cost, low power consumption, and ease of realizing flexible displays, it has broad application prospects.

[0004] However, there are still some problems to be solved in display devices formed by light-emitting diodes. For example, the threshold voltage compensation of the driving transistors. If the corresponding compensation is not set, it will eventually lead to changes in screen brightness, causing flickering, uneven brightness and other phenomena that affect the display effect.

[0005] Therefore, in order to meet the market's pursuit of high-quality display effects, developing a technology or method that can improve the above-mentioned problems has become an urgent need in the current display technology field. Summary of the Invention

[0006] The purpose of this invention is to provide an OLED pixel circuit, display panel, and driving method, which aims to improve the threshold voltage offset problem of the driving transistor and enhance the display effect.

[0007] According to one aspect of the present invention, an OLED pixel circuit is provided, comprising: a driving module, wherein a first path terminal of the driving module is connected to a power supply voltage, and a second path terminal provides a driving current; the driving module includes a driving transistor and a second switch, wherein a first terminal of the driving transistor is connected to a second node, a second terminal of the driving transistor is connected to a second terminal of the second switch, and a control terminal of the driving transistor is connected to a second terminal of a second capacitor and a first node; the control terminal of the second switch receives a driving signal, the first terminal of the second switch is connected to the first node, a second terminal is connected to the power supply voltage, and a fourth terminal is connected to the driving current, and the second terminal of the second switch is selectively connected to the second node and the fourth node; a compensation module for compensating the voltage of the first node, comprising a first capacitor and a second capacitor, wherein a first terminal of the first capacitor is connected to the first node, a second terminal is connected to a third node, and a first terminal of the second capacitor is connected to the power supply voltage and a second terminal is connected to the first node; an input module for providing a data voltage corresponding to grayscale data to the third node; and a light-emitting diode connected to the fourth node to receive the driving current.

[0008] Optionally, it also includes a reset module for providing a first input voltage to the third node and a second input voltage to the fourth node.

[0009] Optionally, the operating cycle of the OLED pixel circuit includes: a reset phase, in which the reset module connects the first input voltage to the third node and connects the second input voltage to the light-emitting diode through the fourth node; the driving module provides a low level to the second node, the connection between the second node and the power supply voltage and the second terminal of the second switch is disconnected, the second switch is turned on, and the first node is connected to the fourth node through the second switch; an improvement phase, in which the reset module disconnects the connection between the first input voltage and the third node, and the second input voltage is connected to the light-emitting diode through the fourth node; the driving module provides a high level to the second node, the driving transistor is turned off, and the connection between the second terminal of the second switch and the second node and the fourth node is disconnected.

[0010] During the compensation phase, the reset module connects the first input voltage to the third node; the driving transistor of the driving module is turned on, and the supply voltage is transmitted from the driving transistor to the first node through the second node; during the write phase, the input module charges the capacitor of the compensation module, adjusts the voltage of the third node to the data voltage, adjusts the voltage of the first node to the driving voltage, and the driving module turns off the second switch and disconnects the second switch from the supply voltage and the anode of the light-emitting diode during the write phase; during the light-emitting phase, the driving module connects the supply voltage to the anode of the light-emitting diode through the second node and the fourth node.

[0011] Optionally, the working cycle of the OLED pixel circuit further includes: a preparation phase, which is located between the improvement phase and the compensation phase, wherein the reset module disconnects the connection between the second input voltage and the fourth node during the preparation phase; and the driving module provides a high level to the second node.

[0012] The aforementioned OLED pixel circuit, wherein the driving module further includes a first switch, a third switch, and a fourth switch, wherein a first terminal of the first switch is connected to the power supply voltage, a second terminal of the first switch is connected to the second node, and a control terminal of the first switch receives a first control signal; a first terminal of the third switch is connected to the second terminal of the second switch, a second terminal of the third switch is connected to the fourth node, and a control terminal of the third switch receives a second control signal; a first terminal of the fourth switch is connected to the second node, a second terminal of the fourth switch receives the second control signal, and a control terminal of the fourth switch receives the first control signal.

[0013] The input module of the aforementioned OLED pixel circuit further includes a fifth switch transistor. The first terminal of the fifth switch transistor receives the data voltage, the second terminal of the fifth switch transistor is connected to the third node, and the control terminal of the fifth switch transistor receives a third control signal.

[0014] Optionally, the reset module further includes a sixth switch and a seventh switch. The first terminal of the sixth switch is connected to the first input voltage, the second terminal of the sixth switch is connected to the third node, and the control terminal of the sixth switch receives the fourth control signal. The first terminal of the seventh switch is connected to the second input voltage, the second terminal of the seventh switch is connected to the fourth stage and the anode of the light-emitting diode, and the control terminal of the seventh switch receives the fifth control signal.

[0015] Optionally, the second and fourth switching transistors are N-channel metal-oxide-semiconductor field-effect transistors; the first, third, and fifth switching transistors and the sixth to seventh switching transistors are all P-channel low-temperature polysilicon field-effect transistors.

[0016] According to another aspect of the present invention, an electronic device is also provided, which includes a display panel as described above.

[0017] According to another aspect of the present invention, a chip is also provided, which includes the pixel compensation circuit described above.

[0018] According to another aspect of the present invention, a display panel is provided, comprising a plurality of the above-described OLED pixel circuits, wherein the display panel is one of a light-emitting diode display panel, a mini light-emitting diode display panel, a quantum dot light-emitting diode display panel, and an organic light-emitting diode display panel.

[0019] According to another aspect of the present invention, a driving method for an OLED pixel circuit is provided for driving the OLED pixel circuit described above. The driving method includes: in a compensation phase, the reset module provides a first input voltage to the third node, the driving module provides a power supply voltage to the second node, the driving transistor is turned on, and the power supply voltage is connected to the first node to achieve threshold voltage compensation for the driving transistor.

[0020] Optionally, it also includes a reset phase, wherein the reset module connects the first input voltage to the third node and the second input voltage to the fourth node; the drive module turns on the second switch, connects the first node to the fourth node through the second switch, and provides a low level to the second node.

[0021] The OLED pixel circuit, display panel, and driving method provided in this invention achieve threshold voltage compensation of the driving transistor by setting a compensation module. Specifically, an 8-transistor and 2-capacitor design is adopted. During the reset phase, a reset voltage is provided to the third and fourth nodes, and during the compensation phase, a power supply voltage and a threshold compensation voltage for the driving transistor are provided to the first node to achieve threshold voltage compensation, thereby improving phenomena such as changes in screen brightness and screen flicker. Through data reset of the capacitor, the short-term image retention problem of the light-emitting diode can also be improved. Attached Figure Description

[0022] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings.

[0023] Figure 1 A schematic diagram of an OLED pixel circuit according to an embodiment of the present invention is shown; Figure 2 This diagram shows the signal timing of an OLED pixel circuit according to an embodiment of the present invention. Figure 3 This diagram illustrates the operation of the OLED pixel circuit during the reset phase according to an embodiment of the present invention. Figure 4 This diagram illustrates the operation of the OLED pixel circuit during the improvement phase according to an embodiment of the present invention. Figure 5 This diagram illustrates the operation of the OLED pixel circuit during the preparation stage according to an embodiment of the present invention. Figure 6 This diagram illustrates the operation of the OLED pixel circuit during the compensation stage according to an embodiment of the present invention. Figure 7 This diagram illustrates the operation of an OLED pixel circuit during the writing stage according to an embodiment of the present invention. Figure 8 This diagram illustrates the operation of an OLED pixel circuit during the light-emitting stage, according to an embodiment of the present invention. Detailed Implementation

[0024] The invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale. Furthermore, some well-known parts may not be shown.

[0025] This application describes many specific details of the invention, such as the specific structure, dimensions, connection relationships, and techniques of the modules, in order to provide a clearer understanding of the invention. However, as those skilled in the art will understand, the invention may be implemented without following these specific details.

[0026] This invention can be presented in various forms, some of which will be described below.

[0027] Figure 1 A schematic diagram of an OLED pixel circuit according to an embodiment of the present invention is shown; as follows: Figure 1 As shown, the OLED pixel circuit is used to drive the light-emitting diode (OLED). The OLED pixel circuit includes: a driving module 10, a compensation module 20, an input module 30, and a reset module 40.

[0028] The driving module 10 includes a driving transistor M3 and a switching transistor M5. The control terminal of the switching transistor M5 receives a driving signal T2. The first terminal of the switching transistor M5 is connected to the first node N1, and the second terminal of the switching transistor M5 is connected to the second node N2 through the driving transistor M3. The second terminal of the switching transistor M5 is also connected to the fourth node N4 through the switching transistor M7. By controlling the on / off state of the driving transistors M3 and M7, the second terminal of the switching transistor M5 is selectively connected to the second node N2 and the fourth node N4. The driving module 10 also includes switching transistors M1 and M8. The first terminal of the switching transistor M1 is connected to the supply voltage ELVDD, and the second terminal of the switching transistor M1 is connected to the second node N2. The control terminal of the switching transistor M1 receives a control signal E1. The first terminal of the switching transistor M8 is connected to the second node N2, and the second terminal of the switching transistor M8 receives a control signal E2. The control terminal of the switching transistor M8 receives a control signal E1. The control terminal of the driving transistor M3 is connected to the first node N1, and the control terminal of the switching transistor M7 receives a control signal E2. The fourth node N4 is connected to the light-emitting diode (OLED) to provide driving current. The compensation module 20 includes a first capacitor C1 and a second capacitor C2. The first terminal of the first capacitor C1 is connected to the first node N1, and the second terminal of the first capacitor C1 is connected to the third node N3. The first terminal of the second capacitor C2 is connected to the power supply voltage ELVDD, and the second terminal of the second capacitor C2 is connected to the first node N1 and to the control terminal of the driving transistor M3. The first node N1 is compensated through capacitors C1 and C2.

[0029] The input module 30 includes a switching transistor M2. The first terminal of the switching transistor M2 receives the data voltage vdata corresponding to the grayscale data. The second terminal of the switching transistor M2 is connected to the second terminal of the first capacitor C1 at the third node N3. The control terminal of the switching transistor M2 receives the control signal T4.

[0030] The reset module 40 includes a switch M6 and a switch M4. The first terminal of switch M6 receives a first input voltage vint1, and the second terminal of switch M6 is connected to the second terminal of the first capacitor C1 at the third node N3 to provide the first input voltage vint1 to the third node N3. The control terminal of switch M6 receives a control signal T3. The first terminal of switch M4 receives a second input voltage vint2, and the second terminal of switch M4 is connected to the positive terminal of the light-emitting diode OLED at the fourth node N4 to provide the second input voltage vint2 to the light-emitting diode OLED. The control terminal of switch M4 receives a control signal T1.

[0031] The anode of the light-emitting diode (OLED) is connected to the fourth node N4, and the cathode of the OLED receives the common ground voltage ELVSS, which is opposite in level to the supply voltage ELVDD.

[0032] This circuit design can effectively compensate for the threshold voltage Vth of the driving transistor M3, thereby improving phenomena such as changes in screen brightness and screen flicker; this OLED pixel circuit can also improve the short-term image retention problem of light-emitting diode OLED.

[0033] The light-emitting diode (OLED) has, for example, a turn-on voltage, and emits light when the voltage difference between the anode and cathode of the OLED is greater than or equal to the turn-on voltage. In this embodiment, the OLED can also be a quantum dot light-emitting diode (QLED).

[0034] Specifically, in this embodiment, both switch M5 and switch M8 are, for example, N-channel oxide semiconductor field-effect transistors (Oxide MOS transistors). The gate of switch M5 serves as the control terminal, the drain of switch M5 is the first terminal, and the source of switch M5 is the second terminal.

[0035] Switching transistors M1, M2, M4, M6, and M7 are, for example, P-channel low-temperature polysilicon field-effect transistors (LTPS MOS transistors). Like switching transistor M8, they all function as switches. The control terminal of these switching transistors is the gate, the first terminal is the source, and the second terminal is the drain; or the first terminal is the drain and the second terminal is the source. No distinction is made here.

[0036] In this embodiment, the N-type MOSFET is turned on under a high-level signal and turned off under a low-level signal, while the P-type MOSFET is turned off under a high-level signal and turned on under a low-level signal.

[0037] Figure 2 The following is a partial timing diagram of the periodic signals of the OLED pixel circuit according to an embodiment of the present invention, as shown below. Figure 2 As shown, the working cycle of this OLED pixel circuit includes, for example, five stages: reset stage, improvement stage, preparation stage, compensation stage, writing stage, and light emission stage, which correspond to... Figure 2 The time periods S1, S2, S3, S4, S5, and S6 are included.

[0038] In the following description, high-level signals and low-level signals refer to logic signals, which are only used to better explain the working process of the embodiments of this application, and the specific voltage values ​​are not described in detail.

[0039] Figure 3 This diagram illustrates the operation of the OLED pixel circuit during the reset phase according to an embodiment of the present invention; as shown. Figure 3As shown, during the reset phase, when control signal E1 is high, switch M1 is off and switch M8 is on; when control signal E2 is low, switch M7 is on, and the low level is transmitted to the second node N2 through switch M8; when control signal T1 is low, switch M4 is on, and the second input voltage vint2 is transmitted to the fourth node N4; when drive signal T2 is high, switch M5 is on, and the second input voltage vint2 is transmitted to the first node N1; when control signal T3 is low, switch M6 is on, and the first input voltage vint1 is transmitted to the third node N3; when control signal T4 is high, switch M2 is off, cutting off the connection between the data voltage vdata and the third node N3.

[0040] During this stage, the voltages at each node are shown in the table below:

[0041] The first input voltage Vint1 is transmitted to the third node N3 through switch M6. The second input voltage Vint2 is transmitted to the first node N1 through switch M4, the fourth node N4, switch M7, and switch M5 to reset the first capacitor C1. The second input voltage Vint2 is transmitted to the fourth node N4 through switch M4 to reset the anode of the light-emitting diode (OLED). The second input voltage Vint2 is transmitted to the first node N1 through switch M4, the fourth node N4, switch M7, and switch M5 to reset the second capacitor C2. The low level of the control signal E2 is transmitted to the second node N2 through switch M8 to improve the short-term image retention problem of the light-emitting diode (OLED).

[0042] Figure 4 This diagram illustrates the operation of the OLED pixel circuit during the improvement phase according to an embodiment of the present invention; as shown. Figure 4 As shown, during the improvement phase, when control signal E1 is high, switch M1 is off and switch M8 is on; when control signal E2 is high, switch M7 is off, and the high level is transmitted to the second node N2 through switch M8; when control signal T1 is low, switch M4 is on, and the second input voltage vint2 is transmitted to the fourth node N4; when control signal T2 is low, switch M5 is off; when control signal T3 is high, switch M6 is off; and when control signal T4 is high, switch M2 is off.

[0043] During this stage, the voltages at each node are shown in the table below:

[0044] Specifically, in the improvement phase, the voltage of the first node N1 is maintained at vint2 through the first capacitor C1 and the second capacitor C2. The voltage of the second node N1 goes high with the control signal E2. The voltage of the third node N3 is maintained at vint1 through the first capacitor C1. The second input voltage vint2 is transmitted to the fourth node N4 through the switching transistor M4, and the voltage of the fourth node N4 is vint2. This phase can improve the short-term image retention problem of light-emitting diode OLEDs.

[0045] Figure 5 This diagram illustrates the operation of the OLED pixel circuit during the preparation stage according to an embodiment of the present invention; as shown below. Figure 5 As shown, during the preparation phase, when control signal E1 is high, switch M1 is off and switch M8 is on; when control signal E2 is high, switch M7 is off, and the high level is transmitted to the second node N2 through switch M8; when control signal T1 is high, switch M4 is off, and the fourth node N4 is disconnected from the second input voltage vint2; when control signal T2 is low, switch M5 is off; when control signal T3 is high, switch M6 is off; and when control signal T4 is high, switch M2 is off.

[0046] During this stage, the voltages at each node are shown in the table below:

[0047] During the preparation phase, Figure 4 Based on the improvement phase, by changing the control signal T1 to a high level, the switching transistor M4 is turned off, and the connection between the second input voltage vint2 and the fourth node N4 and the positive terminal of the light-emitting diode OLED is disconnected.

[0048] Figure 6 This diagram illustrates the operation of the OLED pixel circuit during the compensation stage according to an embodiment of the present invention; as shown. Figure 6 As shown, during the compensation phase, when control signal E1 is low, switch M1 is turned on and switch M8 is turned off, and the supply voltage ELVDD is transmitted to the second node N2; when control signal E2 is high, switch M7 is turned off; when control signal T1 is high, switch M4 is turned off; when drive signal T2 is high, switch M5 is turned on, and the supply voltage ELVDD is transmitted to the first node N1; when control signal T3 is low, switch M6 is turned on, and the first input voltage vint1 is transmitted to the third node N3; when control signal T4 is high, switch M2 is turned off, disconnecting the data voltage vdata from the third node N3.

[0049] During this stage, the voltages at each node are shown in the table below:

[0050] During the compensation phase, due to the capacitance characteristics of the first capacitor C1 and the second capacitor C2 (the voltage across the capacitor will not change abruptly), the voltage of the first node N1 is coupled to ELVDD+Vth, and the driving transistor M3 is turned on. Here, Vth is the threshold voltage of the driving transistor M3. The second terminal of the switching transistor M5 is connected to the second node N2. In this compensation phase, the threshold voltage of the driving transistor M3 is compensated.

[0051] Figure 7 This diagram illustrates the operation of the OLED pixel circuit during the writing stage according to an embodiment of the present invention; as shown below. Figure 7 As shown, during the write phase, when control signal E1 is low, switch M1 is turned on and switch M8 is turned off, and the supply voltage ELVDD is transmitted to the second node N2 through switch M1; when control signal E2 is high, switch M7 is turned off; when control signal T1 is high, switch M4 is turned off; when drive signal T2 is low, switch M5 is turned off; when control signal T3 is high, switch M6 is turned off; when control signal T4 is low, switch M2 is turned on, and the data voltage vdata is transmitted to the third node N3.

[0052] During this stage, the voltages at each node are shown in the table below:

[0053] During the write phase, the data voltage vdata is transmitted to the third node N3 through the switch M2, and the voltage of the first node N1 becomes ELVDD+Vth+(vdata-vint1)*[C1 / (C1+C2)], where ELVDD is the supply voltage, Vth is the threshold voltage of the driving transistor M3, vdata is the data voltage corresponding to the grayscale data, vint1 is the first input voltage, C1 is the first capacitor, and C2 is the second capacitor; the driving transistor M3 is turned off, and the switch M5 is turned off, thus realizing the writing of the data voltage vdata in this write phase.

[0054] Figure 8 This diagram illustrates the operation of an OLED pixel circuit during the light-emitting stage according to an embodiment of the present invention. Figure 8 As shown, during the light-emitting stage, when control signal E1 is low, switch M1 is turned on and switch M8 is turned off, and the supply voltage ELVDD is transmitted to the second node N2 through switch M1; when control signal E2 is low, switch M7 is turned on, and the second terminal of switch M5 is connected to the fourth node N4; when control signal T1 is high, switch M4 is turned off; when drive signal T2 is low, switch M5 is turned off; when control signal T3 is high, switch M6 is turned off; when control signal T4 is high, switch M2 is turned off.

[0055] During this stage, the voltages at each node are shown in the table below:

[0056] During this light-emitting stage, driving transistor M3 is turned on. The supply voltage ELVDD is connected to the positive terminal of the LED (OLED) through switching transistor M1, driving transistor M3, and switching transistor M7. The negative terminal of the LED (OLED) is connected to the common ground voltage ELVSS. The voltage at the first node N1 is ELVDD + Vth + (vdata - vint1) * [C1 / (C1 + C2)], and the voltage at the second node N2 is ELVDD. According to the transistor saturation current formula: I OLED ∝(Vgs-Vth) 2 I OLED ∝[ELVDD+Vth+(vdata-vint1)*[C1 / (C1+C2)]-ELVDD-Vth] 2 I OLED =WC ox μ / 2L*{(vdata-vint1)*[C1 / (C1+C2)]} 2 Among them, I OLED This represents the driving current flowing to the OLED, ∝ indicates proportionality, Vgs represents the voltage difference between the gate and source of the driving transistor M3 in the OLED pixel circuit, W is the channel width of the driving transistor M3, L is the channel length of the driving transistor M3, and C... ox Here, μ is the gate oxide capacitance per unit area of ​​the driving transistor M3, μ is the carrier mobility, Vth is the threshold voltage of the driving transistor M3, vdata is the data voltage, ELVDD is the supply voltage, W and L are fixed during the design of the driving transistor, and C... ox It depends on the thickness and material of the insulation layer at the control end.

[0057] The OLED pixel circuit, display panel, and driving method provided in this invention achieve threshold voltage compensation of the driving transistor by setting a compensation module. Specifically, an 8-transistor and 2-capacitor design is adopted. During the reset phase, a reset voltage is provided to the third and fourth nodes, and during the compensation phase, a power supply voltage and a threshold compensation voltage for the driving transistor are provided to the first node to achieve threshold voltage compensation, thereby improving phenomena such as changes in screen brightness and screen flicker. Through data reset of the capacitor, the short-term image retention problem of the light-emitting diode can also be improved.

[0058] The above description does not provide detailed explanations of the technical aspects of electrode patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc., of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0059] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. The scope of the invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. An OLED pixel circuit, characterized in that, include: The drive module has a first path terminal connected to the power supply voltage and a second path terminal providing drive current. The driving module includes a driving transistor, a first switching transistor, a second switching transistor, a third switching transistor, and a fourth switching transistor. The first terminal of the driving transistor is connected to a second node, and the second terminal of the driving transistor is connected to the second terminal of the second switching transistor. The control terminal of the driving transistor is connected to the second terminal of a second capacitor and the first node. The first terminal of the first switching transistor is connected to the power supply voltage, and the second terminal of the first switching transistor is connected to the second node. The control terminal of the first switching transistor receives a first control signal. The control terminal of the second switching transistor receives a driving signal, and the first terminal of the second switching transistor is connected to the first node. The second terminal of the second switching transistor is selectively connected to the second node and the fourth node. The first terminal of the third switching transistor is connected to the second terminal of the second switching transistor, and the second terminal of the third switching transistor is connected to the fourth node. The control terminal of the third switching transistor receives a second control signal. The first terminal of the fourth switching transistor is connected to the second node, and the second terminal of the fourth switching transistor receives the second control signal. The control terminal of the fourth switching transistor receives the first control signal. The compensation module is used to compensate the voltage of the first node, and includes a first capacitor and a second capacitor. The first terminal of the first capacitor is connected to the first node and the second terminal is connected to the third node. The first terminal of the second capacitor is connected to the power supply voltage and the second terminal is connected to the first node. The input module is used to provide the data voltage corresponding to the grayscale data to the third node; A light-emitting diode (LED) is connected to the fourth node to receive the driving current. The OLED pixel circuit further includes a reset module. During the reset phase of the OLED pixel circuit, the reset module connects a first input voltage to the third node and a second input voltage to the light-emitting diode through the fourth node. The driving module provides a low level to the second node, disconnecting the connection between the second node and the power supply voltage and the second terminal of the second switch. The second switch is turned on, and the first node is connected to the fourth node through the second switch. The duty cycle of the OLED pixel circuit also includes: During the improvement phase, the reset module disconnects the connection between the first input voltage and the third node, and the second input voltage is connected to the light-emitting diode through the fourth node; the second control signal provides a high level to the second node through the fourth switch, the second switch is turned off, and the second terminal of the second switch is disconnected from the second node and the fourth node; During the compensation phase, the reset module connects the first input voltage to the third node; the second switch of the drive module is turned on, and the power supply voltage is transmitted from the second switch to the first node through the second node; During the writing phase, the input module charges the capacitor of the compensation module, adjusts the third node voltage to the data voltage, and adjusts the first node voltage to the drive voltage. During the writing phase, the drive module turns off the second switch and disconnects the second switch from the power supply voltage and the anode of the light-emitting diode. During the light-emitting phase, the driving module connects the power supply voltage to the anode of the light-emitting diode through the second node and the fourth node.

2. The OLED pixel circuit according to claim 1, characterized in that, The duty cycle of the OLED pixel circuit also includes: In the preparation phase, which is located between the improvement phase and the compensation phase, the reset module disconnects the connection between the second input voltage and the fourth node; the drive module provides a high level to the second node.

3. The OLED pixel circuit according to claim 1, characterized in that, The input module also includes a fifth switch, the first terminal of which receives the data voltage, the second terminal of which is connected to the third node, and the control terminal of which receives a third control signal.

4. The OLED pixel circuit according to claim 3, characterized in that, The reset module further includes a sixth switch and a seventh switch. The first terminal of the sixth switch is connected to the first input voltage, the second terminal of the sixth switch is connected to the third node, and the control terminal of the sixth switch receives a fourth control signal. The first terminal of the seventh switch is connected to the second input voltage, the second terminal of the seventh switch is connected to the fourth node and the anode of the light-emitting diode, and the control terminal of the seventh switch receives a fifth control signal.

5. The OLED pixel circuit according to claim 4, characterized in that, The second and fourth switching transistors are N-channel metal-oxide-semiconductor field-effect transistors; the first, third, and fifth switching transistors and the sixth to seventh switching transistors are all P-channel low-temperature polysilicon field-effect transistors.

6. A display panel comprising a plurality of OLED pixel circuits as described in any one of claims 1-5, wherein the display panel is one of a light-emitting diode display panel, a mini light-emitting diode display panel, a quantum dot light-emitting diode display panel, and an organic light-emitting diode display panel.

7. An electronic device, characterized in that, Includes the display panel according to claim 6.

8. A chip, characterized in that, Includes the OLED pixel circuit according to any one of claims 1-5.

9. A driving method for an OLED pixel circuit, used to drive the OLED pixel circuit as described in any one of claims 1-5, the driving method comprising: During the compensation phase, the reset module provides the first input voltage to the third node, the drive module provides the power supply voltage to the second node, the second switch is turned on, and the power supply voltage is connected to the first node to achieve threshold voltage compensation for the drive transistor.

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