Pixel circuit, pixel driving method and display panel

Abstract

This application belongs to the field of display driving technology, specifically relating to a pixel circuit, a pixel driving method, and a display panel. The pixel circuit includes a pixel driving module for outputting a corresponding driving current to the driving node in response to the scanning signal on the scan line and the data signal on the data line during the scanning phase; a light emission control module for causing the control node to be at an invalid potential during the scanning phase in response to the triggering of the scanning signal; and causing the control node to be at an effective potential during the light emission phase under the triggering of the light emission control signal on the light emission control line; and a switching module for controlling the on / off connection between the driving node and the light emission module according to the potential on the control node. This application, through the coordinated work of the pixel driving module, the light emission module, the light emission control module, and the switching module, achieves normal display function while converting the wide-pulse light emission control signal into a narrow-pulse signal similar to the scanning signal, thereby improving the compatibility between the light emission control signal and the scanning signal.

Description

Technical Field

[0001] This disclosure belongs to the field of display driving technology, specifically relating to a pixel circuit, a pixel driving method, and a display panel. Background Technology

[0002] AMOLED (Active Matrix Organic Light Emitting Diode) display technology is widely used in various display devices due to its advantages such as self-illumination, high contrast, and low power consumption. Its pixel circuit typically adopts a 3T1C structure, controlling the current of the driving transistors through data voltage, thereby adjusting the brightness of the OLED.

[0003] However, in current AMOLED pixel circuits, the emission control signal used to control pixel emission has a significantly different waveform from the scanning signal, making the emission driving circuit incompatible with mature scanning driving circuits. This necessitates a separate and complex circuit design. This not only increases the complexity of the circuit design and the difficulty of control but also occupies layout space, hindering the implementation of narrow bezel designs for display panels.

[0004] Therefore, improving the compatibility between the light emission control signal and the scanning signal in the pixel circuit to simplify the design of the peripheral driving circuit is an urgent problem to be solved. Summary of the Invention

[0005] This application provides a pixel circuit, a pixel driving method, and a display panel. Through the coordinated operation of a pixel driving module, a light-emitting module, a light-emitting control module, and a switching module, while realizing normal display functions, the wide-pulse light-emitting control signal is converted into a narrow-pulse signal similar to the scanning signal, thereby improving the compatibility between the light-emitting control signal and the scanning signal.

[0006] In a first aspect, this application provides a pixel circuit, the pixel circuit comprising: a pixel driving module connected to a scan line, a data line, and a driving node, configured to: during the scanning phase, output a corresponding driving current to the driving node in response to a scan signal on the scan line and a data signal on the data line; a light-emitting module configured to: emit light of a corresponding brightness in response to the driving current; a light-emitting control module connected to the scan line, a light-emitting control line, and a control node, configured to: in response to the triggering of the scan signal, cause the control node to be at an invalid potential during the scanning phase; and, under the triggering of a light-emitting control signal on the light-emitting control line, cause the control node to be at an effective potential during the light-emitting phase; wherein the waveform of the light-emitting control signal is the same as the waveform of the scan signal, and there is a preset phase difference between the light-emitting control signal and the scan signal; and a switching module connected to the control node, the driving node, and the light-emitting module, configured to: control the on / off state between the driving node and the light-emitting module according to the potential on the control node.

[0007] Optionally, the light emission control module includes: a reset unit connected to the scan line and the control node respectively, configured to: pull the control node down to a low potential in response to the effective potential of the scan signal; a charging unit connected to the light emission control line and the control node respectively, configured to: transmit the light emission control signal to the control node in response to the effective potential of the light emission control signal; and an energy storage unit connected to the control node, configured to: store the potential of the control node.

[0008] Optionally, the reset unit includes: a first transistor, the control terminal of the first transistor being connected to the scan line, the first terminal of the first transistor being connected to the control node, and the second terminal of the first transistor being connected to a low-level terminal.

[0009] Optionally, the charging unit includes: a second transistor, the control terminal of the second transistor being connected to the light-emitting control line, the first terminal of the second transistor being connected to the control terminal of the second transistor, and the second terminal of the second transistor being connected to the control node.

[0010] Optionally, the pixel circuit further includes: a third transistor, wherein the control terminal of the third transistor is connected to the scan line, the first terminal of the third transistor is connected to the driving node, and the second terminal of the third transistor is connected to a low-level terminal.

[0011] The pixel circuit further includes a fourth transistor, the control terminal of which is connected to the detection control line, the first terminal of which is connected to the driving node, and the second terminal of which is connected to the detection acquisition line.

[0012] Secondly, this application provides a pixel driving method applied to a pixel circuit. The pixel driving method includes: during the scanning phase, outputting a driving current to a driving node through a pixel driving module; and controlling a switching module to disconnect the driving node from the light-emitting module through a light-emitting control module; during the light-emitting phase, controlling the switching module to connect the driving node to the light-emitting module through the light-emitting control module, so that the driving current drives the light-emitting module to emit light.

[0013] Optionally, the light-emitting control module includes a reset unit, a charging unit, and an energy storage unit; controlling the switching module to disconnect the driving node from the light-emitting module via the light-emitting control module includes: during the scan triggering period of the scan phase, the reset unit responds to the effective potential of the scan signal by pulling the control node down to a low potential; and the energy storage unit keeps the control node at a low potential throughout the scan phase, so that the switching module is in an off state.

[0014] The connection between the driving node and the light-emitting module is controlled by the light-emitting control module to be made by the switching module. This includes: during the light-emitting control period of the light-emitting phase, the control node is charged to a high potential by the effective potential of the light-emitting control signal through the charging unit; and the control node is kept at a high potential throughout the light-emitting phase by the energy storage unit, so that the switching module is in the on state.

[0015] Optionally, the pixel circuit includes a fourth transistor, and the pixel driving method further includes: during the detection period of the scanning phase, while the scan line outputs an invalid scan signal, the detection control line outputs an valid detection control signal to control the fourth transistor to be turned on, so as to obtain the characteristic parameters of the driving transistor through the detection acquisition line.

[0016] Thirdly, this application provides a display panel, which includes multiple scan lines, multiple data lines, and multiple light emission control lines. The display panel also includes an array of pixel circuits, which are electrically connected to the scan lines, the data lines, and the light emission control lines, respectively.

[0017] The technical solution provided in this application has at least the following beneficial effects:

[0018] The pixel circuit of this application, through the coordinated operation of the pixel driving module, the light-emitting module, the light-emitting control module, and the switching module, achieves normal display functions while transforming the wide-pulse light-emitting control signal, which originally required a complex EOA circuit, into a narrow-pulse signal that can be generated by a simple circuit with the same architecture as the GOA. By adjusting the phase difference between the light-emitting control signal and the scanning signal, the light-emitting duty cycle of the light-emitting module can be precisely controlled. This allows the EOA circuit driving the light-emitting control signal to share the same set of clock signals and noise reduction circuits as the GOA circuit driving the scanning signal, greatly simplifying the design of peripheral driving circuits and significantly saving layout space in non-display areas. This provides key technical support for realizing narrow-bezel display panels. At the same time, since the EOA can directly reuse the mature design experience and repair solutions of the GOA, the overall reliability of the product is effectively improved. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0020] Figure 1 The image shows an OLED pixel circuit in a related technology.

[0021] Figure 2 The diagram shown is a schematic diagram of a display panel architecture provided in an embodiment of this application.

[0022] Figure 3 As shown Figure 1 The waveform diagram of the pixel circuit shown is shown.

[0023] Figure 4 The diagram shown is a schematic diagram of the architecture of a gate driving circuit provided in an embodiment of this application.

[0024] Figure 5 The diagram shown is a schematic diagram of a pixel circuit provided in an embodiment of this application.

[0025] Figure 6 The diagram shown is a driving timing diagram provided in an embodiment of this application.

[0026] Figure 7 The diagram shown is a schematic diagram of another pixel circuit provided in an embodiment of this application.

[0027] Figure 8 The diagram shown is a schematic diagram of the first pixel circuit provided in the embodiment of this application.

[0028] Figure 9 The diagram shown is a schematic diagram of the second pixel circuit provided in an embodiment of this application.

[0029] Figure 10 The diagram shown is another driving timing diagram provided in an embodiment of this application.

[0030] Figure 11 The diagram shown is a schematic diagram of the third pixel circuit provided in the embodiment of this application.

[0031] Figure 12 The diagram shown is another driving timing diagram provided in an embodiment of this application.

[0032] Figure 13 The diagram shown is a flowchart of a pixel driving method provided in an embodiment of this application.

[0033] Explanation of reference numerals in the attached figures:

[0034] 100. Pixel circuit;

[0035] 110. Pixel driving module; 120. Light-emitting module; 130. Light-emitting control module; 131. Reset unit; 132. Charging unit; 133. Energy storage unit; 140. Switching module;

[0036] T1, first transistor; T2, second transistor; T3, third transistor; T4, fourth transistor; T5, fifth transistor; T6, sixth transistor; T7, seventh transistor; C1, first capacitor; C2, second capacitor; A, intermediate node; B, driving node; C, control node; OLED, light-emitting diode; Gate, scan line; Data, data line; EM, light emission control line; Sen1, detection control line; Sen2, detection acquisition line; VSS, low-level terminal; VDD, power supply terminal. Detailed Implementation

[0037] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0038] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0039] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be noted that the technical features involved in the various embodiments described below can be combined with each other as long as they do not conflict with each other. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present application, and should not be construed as limiting the present application.

[0040] AMOLED (Active Matrix Organic Light Emitting Diode) is a new display technology that combines organic light-emitting diodes (OLEDs) and active matrix technology. AMOLED displays are characterized by their self-emissive nature, meaning they do not require a backlight and can display more vivid colors and deeper blacks. Because each pixel can emit light independently, AMOLED screens offer higher contrast and lower power consumption.

[0041] The basic circuit of OLED pixels, such as Figure 1 As shown, this basic circuit uses a 3T1C architecture. The scan signal output from the scan line Gate turns on the first transistor T1, and the data signal output from the data line Data is input to the intermediate node A. The voltage at the intermediate node A then controls the current of the second transistor T2 (the driving transistor), allowing current to flow through T2. The first capacitor C1 stores the voltage at the intermediate node A, maintaining a high voltage at T2 to control it. The third transistor T3 is connected in series between the second transistor T2 and the OLED, directly controlling whether it emits light. The gate of the third transistor T3 is the light-emitting control line EM, and its output light-emitting control signal controls the duty cycle of the current frame's light emission, resulting in more precise grayscale control, especially at low grayscale levels. The display panel architecture under this pixel circuit design is as follows: Figure 2 As shown.

[0042] like Figure 3The diagram shows the pixel control waveform of a related technology. When the scan signal output by the scan line of the nth row of pixels is high, the first transistor T1 is turned on, the data signal charges the intermediate node A, and controls the on state of the second transistor T2. However, the third transistor T3 is controlled by the light emission control line EM. Therefore, when the light emission control signal output by the light emission control line EM is low, the OLED still does not emit light. Only when the light emission control signal output by the light emission control line EM is high can the OLED emit light, thus controlling the light emission duty cycle of the OLED. Figure 3 The waveform of the light emission control signal differs significantly from that of the scanning signal. It requires a wider width and needs to be adjusted in real-time according to the duty cycle requirements. Therefore, the light emission driver circuit (EOA) and its control method differ significantly from those of the scanning driver circuit (GOA). Figure 4 The diagram shown is a relatively mature and stable GOA circuit architecture. However, it requires the use of an independent and complex light-emitting driving circuit design. This not only increases the complexity of the circuit design and the difficulty of control, but also occupies layout space and is not conducive to realizing the narrow bezel design of the display panel.

[0043] Therefore, in order to improve the compatibility between the light emission control signal and the scanning signal in the pixel circuit and simplify the design of the peripheral driving circuit, this application provides a pixel circuit, specifically including the following embodiments:

[0044] Figure 5 The diagram shown is a schematic representation of a pixel circuit 100 provided in an embodiment of this application; as shown Figure 5 As shown, the pixel circuit 100 includes a pixel driving module 110, which is connected to the scan line Gate, the data line Data, and the driving node B, respectively, and is configured to output a corresponding driving current to the driving node B in response to the scan signal on the scan line Gate and the data signal on the data line Data during the scanning phase.

[0045] It should be noted that, in this embodiment, the pixel driving module 110, as a signal conversion unit, responds to the effective level of the scan signal on the scan line Gate during the scanning period, receives the data signal on the data line Data, and converts it into a corresponding driving current before inputting it to the driving node B. The magnitude of this driving current precisely corresponds to the desired display grayscale, and maintains a stable output within the frame period through an internal storage mechanism. The pixel driving module 110 ensures the accuracy and stability of the display brightness, providing a reliable current reference for the subsequent light-emitting module 120.

[0046] In this embodiment, the pixel circuit 100 further includes a light-emitting module 120, which is configured to emit light of a corresponding brightness in response to the driving current. Specifically, the light-emitting module 120 in this embodiment is a current-driven light-emitting device, such as an OLED (Organic Light Emitting Diode), whose luminous brightness is proportional to the driving current flowing through it. When the driving current output by the driving node B flows through the light-emitting module 120, the light-emitting module 120 emits light of a corresponding brightness.

[0047] In this embodiment, the pixel circuit 100 further includes a light emission control module 130, which is connected to the scan line Gate, the light emission control line EM, and the control node C, respectively. It is configured to: in response to the triggering of the scan signal, make the control node C at an invalid potential during the scanning phase; and under the triggering of the light emission control signal on the light emission control line EM, make the control node C at an effective potential during the light emission phase.

[0048] In other words, as the output terminal of the light-emitting control module 130, during the scanning phase, when the scanning signal is at an effective level (e.g., high level), the light-emitting control module 130 sets the potential of control node C to an ineffective level (e.g., low level) and maintains this ineffective potential throughout the entire scanning phase. Conversely, during the light-emitting phase, when the light-emitting control signal is at an effective level (e.g., high level), the light-emitting control module 130 sets the potential of control node C to an effective level (e.g., high level) and maintains this effective potential throughout the entire light-emitting phase. Here, the effective and ineffective potentials are relative to the turn-on voltage of the corresponding transistors. When the transistor is a P-type transistor, the corresponding effective potential or effective level is low; when the transistor is an N-type transistor, the corresponding effective potential or effective level is high. In this embodiment, an effective level of high and an ineffective level of low are used as examples.

[0049] It should be noted that since the light emission control module 130 changes and maintains the potential of the control node C solely through the triggering of the scanning signal and the light emission control signal, this allows for the change and maintenance of the potential of the control node C to be achieved when the waveform of the light emission control signal is the same as that of the scanning signal, and when there is a preset phase difference between the two signals. Therefore, through the configuration of the light emission control module 130, the light emission control signal can use a narrow pulse signal with the same waveform as the scanning signal. Only the phase difference between the two needs to be adjusted to generate the required wide pulse control signal at the control node C. This allows the EOA circuit that generates the light emission control signal to use the exact same circuit architecture as the GOA circuit that generates the scanning signal, thereby simplifying the design of the peripheral driving circuit, saving layout space, facilitating the achievement of a narrow bezel, and allowing the absorption of mature reliability experience from GOA.

[0050] In this embodiment, the pixel circuit 100 further includes a switch module 140, which is connected to the control node C, the driving node B and the light-emitting module 120 respectively, and is configured to control the on / off state between the driving node B and the light-emitting module 120 according to the potential on the control node C.

[0051] It should be noted that the switch module 140, acting as a control switch for the on / off state of the light-emitting module, is controlled by the potential of the control node C. When the control node C is at an effective potential, the switch module 140 is turned on, forming a path between the drive node B and the light-emitting module 120, allowing the drive current to flow through the light-emitting module 120 and causing it to emit light; when the control node C is at an ineffective potential, the switch module 140 is turned off, disconnecting the drive node B from the light-emitting module 120, and the light-emitting module 120 does not emit light.

[0052] The operating timing of the pixel circuit 100 in this embodiment is as follows: Figure 6 As shown, the process includes a scanning phase and a light emission phase. The scanning phase includes a scan trigger period and a scan sustain period, while the light emission phase includes a light emission control period and a light emission sustain period. The waveform of the light emission control signal is the same as that of the scanning signal; both are narrow pulse signals, and there is a preset phase difference between them. Here, combined with... Figure 6 The working principle of the pixel circuit 100 in this embodiment is explained as follows:

[0053] (1) Scan trigger period (t1-t2 period): The scan signal is at an effective potential, and the light emission control signal is at an ineffective potential.

[0054] The pixel driving module 110 responds to the valid potential of the scan signal, receives the data signal on the data line Data, generates a driving current corresponding to the data signal, and outputs the driving current to the driving node B; the light emission control module 130 responds to the trigger of the scan signal, so that the control node C is at an invalid potential; since the control node C is at an invalid potential, the switch module 140 is in the off state, and the driving node B is disconnected from the light emission module 120.

[0055] (2) Scan maintenance period (t2-t3 period): The scan signal is still at an effective potential, while the light emission control signal is still at an ineffective potential.

[0056] The pixel driving module 110 stops receiving new data signals, but the already generated driving current continues to be output; the light emission control module 130 keeps the control node C at an invalid potential; and the switch module 140 remains in the off state.

[0057] During the scanning phase, the driving current is generated by the pixel driving module 110, but because the switching module 140 is turned off, the driving current cannot flow through the light-emitting module 120, and the light-emitting module 120 does not emit light, thus realizing the timing separation of the data writing and light-emitting phases.

[0058] (3) Light emission control period (t3-t4 period): The light emission control signal is at an effective potential, and the scanning signal is at an invalid potential.

[0059] The light emission control module 130 responds to the triggering of the light emission control signal, so that the control node C is at an effective potential; since the control node C is at an effective potential, the switch module 140 is in a conducting state, and a path is formed between the drive node B and the light emission module 120; the drive current generated by the pixel drive module 110 during the scanning stage flows through the switch module 140 and the light emission module 120, driving the light emission module 120 to emit light.

[0060] (4) Light emission maintenance period (t4-t5 period): The light emission control signal is still at an effective potential, while the scanning signal is still at an invalid potential.

[0061] The light-emitting control module 130 keeps the control node C at an effective potential; the switch module 140 remains in the on state; and the light-emitting module 120 continues to emit light.

[0062] During the light-emitting stage, the light-emitting module 120 emits light normally, and the light-emitting duty cycle is determined by the phase difference between the light-emitting control signal and the scanning signal.

[0063] Therefore, in the scanning phase, the pixel driving module 110 generates a corresponding driving current based on the input scanning signal and data signal. During the scanning phase, the light emission control module 130 responds to the triggering of the scanning signal, causing the control node C to be at an invalid potential. This, in turn, controls the switch module 140 to disconnect the connection between the driving node B and the light emission module 120, preventing the driving current from flowing through the light emission module 120. During the light emission phase, the light emission control module 130 responds to the triggering of the light emission control signal, causing the control node C to be at an effective potential. This, in turn, controls the switch module 140 to connect the driving node B and the light emission module 120, allowing the driving current to flow through the light emission module 120 and drive it to emit light. The waveform of the light emission control signal is the same as the waveform of the scanning signal, and there is a preset phase difference between them.

[0064] Therefore, based on the structural design of the pixel circuit 100 described above, this application has the following beneficial effects:

[0065] (1) Great simplification of EOA circuit design: Since the external light emission control signal in this application can use a narrow pulse signal with the same waveform as the scanning signal, the light emission duty cycle can be precisely controlled by adjusting only the phase difference between the two. Therefore, the EOA circuit that drives the light emission control signal can directly adopt the same circuit architecture as the GOA, without the need to design a complex circuit structure and timing control scheme for the EOA separately, which greatly simplifies the design of the peripheral driving circuit.

[0066] (2) Resource sharing and layout optimization of the driving circuit: Since the EOA can adopt the same circuit architecture as the GOA, the EOA can share the noise reduction circuit, the same set of noise reduction power signals (LC1 / LC2), and the same set of clock signals (CK) with the GOA. This resource sharing scheme avoids setting up a complex circuit structure and additional signal traces for the EOA separately, significantly reducing the layout area of ​​the non-display area, and providing key technical support for realizing the narrow bezel design of the display panel.

[0067] (3) Effective improvement of product reliability: After years of development, GOA technology has formed mature design experience, problem analysis experience and repair experience. After EOA adopts the same circuit architecture as GOA, it can directly absorb and learn from these mature experiences, thereby effectively improving the reliability of EOA, reducing the product defect rate and improving the overall yield of display panels.

[0068] Figure 7 The diagram shown is a structural schematic of another pixel circuit 100 provided in an embodiment of this application; as shown Figure 7 As shown, the light emission control module 130 includes a reset unit 131, which is connected to the scan line Gate and the control node C respectively. It is configured to pull down the control node C to a low potential in response to the effective potential of the scan signal. In other words, the function of the reset unit 131 is to force the control node C to be in an invalid state during data writing, ensuring that the light emission module 120 does not emit light erroneously during the scanning phase.

[0069] This embodiment achieves precise association between the scanning phase and the control node C through the setting of the reset unit 131, ensuring that the switch module 140 is in the off state during data writing, thus avoiding timing conflicts between data writing and light emission.

[0070] like Figure 7 As shown, the light-emitting control module 130 in this embodiment also includes a charging unit 132, which is connected to the light-emitting control line EM and the control node C respectively, and is configured to transmit the light-emitting control signal to the control node C in response to the effective potential of the light-emitting control signal. That is to say, the function of the charging unit 132 is to put the control node C into an effective state during the light-emitting stage, so that the switch module 140 can be turned on.

[0071] In this embodiment, the setting of the charging unit 132 realizes the direct association between the light emission control signal and the control node C, so that the waveform characteristics of the light emission control signal can be transmitted to the control node C, providing a control basis for the subsequent conduction of the switching module 140.

[0072] like Figure 7As shown, the light-emitting control module 130 of this embodiment also includes an energy storage unit 133, which is connected to the control node C and configured to store the potential of the control node C. That is, the energy storage unit 133 can maintain the potential of the control node C even after the charging unit 132 or the reset unit 131 is turned off. Specifically, when the charging unit 132 completes charging, the energy storage unit 133 stores the high potential of the control node C, so that the control node C remains in an active state even after the charging unit 132 is turned off; when the reset unit 131 completes the pull-down, the energy storage unit 133 stores the low potential of the control node C, so that the control node C remains in an inactive state even after the reset unit 131 is turned off.

[0073] This embodiment achieves stable maintenance of the potential of the control node C by setting the energy storage unit 133, ensuring that the switch module 140 can be continuously turned on during the light emission stage and continuously turned off during the scanning stage, thus avoiding unstable light emission or malfunction caused by potential fluctuations.

[0074] In this embodiment, the reset unit 131, charging unit 132, and energy storage unit 133 work together to achieve the overall function of the light-emitting control module 130. This is combined with... Figure 6 The timing sequence shown illustrates the working principle of the three components in the following way:

[0075] (1) Scan trigger period (t1-t2 period): The scan signal is at an effective potential (high level), and the light emission control signal is at an ineffective potential (low level).

[0076] Reset unit 131 responds to the valid potential of the scan signal and starts working, pulling control node C down to a low potential; energy storage unit 133 stores the low potential of control node C, ensuring that control node C remains at a low potential after reset unit 131 completes the pull-down; since the light emission control signal is an invalid potential, charging unit 132 is in a non-working state and does not output any potential to control node C.

[0077] During this period, control node C is at a low potential (invalid potential), switch module 140 remains off, drive node B is disconnected from light-emitting module 120, and light-emitting module 120 does not emit light.

[0078] (2) Scan maintenance period (t2-t3 period): The scan signal changes from an effective potential to an ineffective potential, while the light emission control signal remains at an ineffective potential.

[0079] The reset unit 131 stops working and no longer pulls down the control node C; since the energy storage unit 133 has stored the low potential of the control node C, the control node C remains at a low potential; the charging unit 132 remains in a non-working state.

[0080] During this period, control node C remains at a low potential, switch module 140 remains off, and light-emitting module 120 does not emit light.

[0081] (3) Light emission control period (t3-t4 period): The light emission control signal is at an effective potential (high level), and the scanning signal is at an ineffective potential (low level).

[0082] The charging unit 132 responds to the effective potential of the light emission control signal and starts working, transmitting the high level of the light emission control signal to the control node C, so that the control node C is charged to a high potential; the energy storage unit 133 stores the high potential of the control node C, ensuring that the control node C continues to maintain a high potential after the charging unit 132 has completed charging; since the scan signal is an invalid potential, the reset unit 131 is in a non-working state and does not output a pull-down potential to the control node C.

[0083] During this period, control node C is at a high potential (effective potential), switch module 140 is turned on, a path is formed between drive node B and light-emitting module 120, and drive current flows through light-emitting module 120 to make it emit light.

[0084] (4) Light emission maintenance period (t4-t5 period): The light emission control signal changes from an effective potential to an ineffective potential, while the scanning signal remains at an ineffective potential.

[0085] The charging unit 132 stops working and no longer charges the control node C; since the energy storage unit 133 has stored the high potential of the control node C, the control node C remains at a high potential; the reset unit 131 remains in a non-working state.

[0086] During this period, control node C remains at a high potential, switch module 140 remains in the conducting state, and light-emitting module 120 continues to emit light.

[0087] (5) Summary of energy storage and retention function

[0088] During the scan maintenance period, the scan signal has become an invalid potential, and the reset unit 131 stops working. However, since the energy storage unit 133 has stored the low potential of the control node C, the control node C remains at a low potential, and the switch module 140 remains in the off state, ensuring that the light-emitting module 120 will not emit light erroneously after the data is written.

[0089] During the light-emitting period, the light-emitting control signal has become an invalid potential, and the charging unit 132 stops working. However, since the energy storage unit 133 has stored the high potential of the control node C, the control node C remains at a high potential, the switching module 140 remains in the conducting state, and the light-emitting module 120 continues to emit light, ensuring the stable maintenance of the light-emitting state.

[0090] The presence of the energy storage unit 133 ensures that the potential of the control node C remains stable even after the charging unit 132 or the reset unit 131 is turned off, thus achieving stable maintenance of the light-emitting state and avoiding flickering caused by sudden potential changes during signal switching. This working mechanism allows the external light-emitting control signal to use a narrow pulse signal with the same waveform as the scanning signal. Only the phase difference between the two needs to be adjusted to precisely control the light-emitting duty cycle, providing key technical support for circuit compatibility between EOA and GOA.

[0091] Therefore, in this embodiment, the reset unit 131 responds to the scan signal by pulling down the control node C to a low potential, ensuring that the light-emitting module 120 does not emit light during the scanning phase; the charging unit 132 responds to the light-emitting control signal by charging the control node C to a high potential, triggering the light-emitting module 120 to emit light; and the energy storage unit 133 stores the potential of the control node C, maintaining the stability of the light-emitting state. The three units work together, allowing the external light-emitting control signal to use a narrow pulse signal with the same waveform as the scan signal, and only the phase difference between the two needs to be adjusted to precisely control the light-emitting duty cycle.

[0092] Therefore, the light emission control module 130 in this embodiment creatively realizes the waveform conversion function of the light emission control signal through the coordinated cooperation of the reset unit 131, the charging unit 132 and the energy storage unit 133. This allows the EOA circuit that drives the light emission control signal to adopt the same circuit architecture as the GOA circuit that drives the scanning signal, which greatly simplifies the design of the peripheral driving circuit, significantly saves layout space, and provides key technical support for realizing narrow bezel display panels and improving product reliability.

[0093] Figure 8 The diagram shown is a circuit diagram of the first pixel circuit 100 provided in an embodiment of this application; as shown Figure 8 As shown, the reset unit 131 includes: a first transistor T1, the control terminal of the first transistor T1 is connected to the scan line Gate, the first terminal of the first transistor T1 is connected to the control node C, and the second terminal of the first transistor T1 is connected to the low-level terminal VSS.

[0094] The charging unit 132 in this embodiment includes: a second transistor T2, the control terminal of the second transistor T2 is connected to the light emission control line EM, the first terminal of the second transistor T2 is connected to the control terminal of the second transistor T2, and the second terminal of the second transistor T2 is connected to the control node C.

[0095] The energy storage unit 133 in this embodiment includes a first capacitor C1. The first end of the first capacitor C1 is connected to the control node C, and the second end of the first capacitor C1 is connected to the low-level terminal VSS.

[0096] In this embodiment, the pixel driving module 110 includes a fifth transistor T5, a sixth transistor T6, and a second capacitor C2; the control terminal of the fifth transistor T5 is connected to the scan line Gate, the first terminal of the fifth transistor T5 is connected to the data line Data, and the second terminal of the fifth transistor T5 is connected to the intermediate node A; the control terminal of the sixth transistor T6 is connected to the intermediate node A, the first terminal of the sixth transistor T6 is connected to the power supply terminal, and the second terminal of the sixth transistor T6 is connected to the driving node B; the first terminal of the second capacitor C2 is connected to the intermediate node A, and the second terminal of the second capacitor C2 is connected to the driving node B; wherein, the sixth transistor T6 serves as the driving transistor for driving the light-emitting module 120.

[0097] In this embodiment, the switching module 140 includes a seventh transistor T7. The control terminal of the seventh transistor T7 is connected to the control node C, the first terminal of the seventh transistor T7 is connected to the driving node B, and the second terminal of the seventh transistor T7 is connected to the anode of the light-emitting diode OLED. The cathode of the light-emitting diode OLED is connected to the low-level terminal VSS.

[0098] Here, combined with Figure 6 The timing sequence shown below explains the working principle of the pixel circuit 100 in this embodiment:

[0099] 1. Scan trigger period (t1-t2 period): The scan signal is at a high level, and the light emission control signal is at a low level.

[0100] (1) Operation of pixel driving module 110: When the control terminal of the fifth transistor T5 receives the high level of the scan signal, the fifth transistor T5 is turned on; the data voltage on the data line Data is transmitted to the intermediate node A through the fifth transistor T5; the control terminal of the sixth transistor T6 is connected to the intermediate node A, the gate voltage of the sixth transistor T6 is set to the data voltage Vdata, and the sixth transistor T6 starts to generate driving current; the second capacitor C2 stores the voltage of the intermediate node A to ensure that the gate voltage of the sixth transistor T6 can still be maintained after the scan signal ends.

[0101] (2) Operation of the light emission control module 130: When the control terminal of the first transistor T1 receives a high level of the scanning signal, the first transistor T1 is turned on; the first transistor T1 pulls the control node C down to the low level potential VSS, making the control node C at a low potential. The first capacitor C1 stores the low potential of the control node C, ensuring that the control node C remains at a low potential during the scanning phase. When the control terminal of the second transistor T2 receives a low level of the light emission control signal EM, the second transistor T2 is in the off state and does not output any potential to the control node C.

[0102] (3) Operation of switch module 140: The control terminal of the seventh transistor T7 is connected to the control node C. Since the control node C is at a low potential, the seventh transistor T7 is in the off state. The driving node B is disconnected from the anode of the light-emitting diode OLED, and the driving current cannot flow through the light-emitting diode OLED.

[0103] (4) Operation of the light-emitting module 120: Since the seventh transistor T7 is turned off, the driving current cannot flow through the light-emitting diode OLED, and the light-emitting diode OLED does not emit light.

[0104] 2. Scan sustaining period (t2-t3 period): The scan signal changes from high level to low level, while the light emission control signal remains at low level.

[0105] (1) Operation of pixel driving module 110: The fifth transistor T5 is turned off, and the intermediate node A no longer receives new data voltage; due to the storage function of the second capacitor C2, the voltage of the intermediate node A remains Vdata, the gate voltage of the sixth transistor T6 remains unchanged, and the sixth transistor T6 continues to generate driving current.

[0106] (2) Operation of the light-emitting control module 130: The first transistor T1 is turned off and no longer pulls down the control node C; due to the storage effect of the first capacitor C1, the control node C remains at a low potential; the second transistor T2 remains in the off state.

[0107] (3) Operation of switch module 140: The seventh transistor T7 is still in the off state, and the drive node B remains disconnected from the anode of the light-emitting diode OLED.

[0108] (4) Operation of the light-emitting module 120: The light-emitting diode OLED still does not emit light.

[0109] During the scan sustain period, the pixel driving module 110 maintains driving capability, the light emission control module 130 maintains the control node C at a low potential, the switching module 140 remains off, and the light-emitting diode OLED does not emit light.

[0110] 3. Light emission control period (t3 to t4): The light emission control signal is at a high level (effective potential), and the scanning signal is at a low level (ineffective potential).

[0111] (1) Operation of the light emission control module 130: When the control terminal of the second transistor T2 receives a high level of the light emission control signal, the second transistor T2 is turned on. Since the second transistor T2 is connected in a diode configuration, the high level of the light emission control signal is transmitted to the control node C, causing the control node C to be charged to a high potential (effective potential). The first capacitor C1 stores the high potential of the control node C, ensuring that the control node C remains at a high potential. The first transistor T1 is turned off, and no pull-down potential is output to the control node C.

[0112] (2) Operation of switch module 140: The control terminal of the seventh transistor T7 is connected to the control node C. Since the control node C is at a high potential, the seventh transistor T7 is turned on. A path is formed between the driving node B and the anode of the light-emitting diode OLED.

[0113] (3) Operation of pixel driving module 110: The fifth transistor T5 is still in the off state; the sixth transistor T6 continues to generate driving current, which flows to driving node B through the second terminal of the sixth transistor T6. Since the seventh transistor T7 is turned on, the driving current flows to the anode of the light-emitting diode OLED through driving node B and the seventh transistor T7.

[0114] (4) Operation of the light-emitting module 120: The driving current flows through the light-emitting diode OLED, and the light-emitting diode OLED emits light of corresponding brightness.

[0115] During the light emission control period, the light emission control module 130 charges the control node C to a high potential, the switch module 140 is turned on, and the driving current generated by the pixel driving module 110 flows through the light-emitting diode OLED to make it emit light.

[0116] 4. Light emission maintenance period (t4-t5 period): The light emission control signal changes from high level to low level, while the scanning signal remains at low level.

[0117] (1) Operation of the light-emitting control module 130: The second transistor T2 is turned off and no longer charges the control node C. Due to the storage effect of the first capacitor C1, the control node C remains at a high potential, and the potential of the control node C will not drop immediately due to the turn-off of the second transistor T2.

[0118] (2) Operation of switch module 140: The seventh transistor T7 remains on.

[0119] (3) Operation of the light-emitting module 120: The driving current continues to flow through the light-emitting diode OLED, and the light-emitting diode OLED continues to emit light.

[0120] During the current time period, even after the light emission control signal goes low, the control node C remains at a high potential due to the storage function of the first capacitor C1, the switch module 140 remains on, and the light emission diode OLED continues to emit light until the scanning phase of the next frame arrives.

[0121] It needs to be further explained that, in Figure 8In the pixel circuit 100, the gate potential of the sixth transistor T6 is controlled by the absolute voltage of the intermediate node A, thereby controlling the driving current. However, during the light-emitting stage, the source potential of the sixth transistor T6 (i.e., the potential of the driving node B) fluctuates due to changes in the OLED's operating state, causing instability in the gate-source voltage Vgs of the sixth transistor T6, affecting the accuracy of the driving current, especially in low grayscale displays.

[0122] Therefore, in order to improve the accuracy of the drive current, in Figure 8 Based on the pixel circuit 100 shown, this embodiment further adds a third transistor T3, specifically as follows: Figure 9 As shown, the pixel circuit 100 also includes: a third transistor T3, the control terminal of the third transistor T3 is connected to the scan line Gate, the first terminal of the third transistor T3 is connected to the driving node B, and the second terminal of the third transistor T3 is connected to the low-level terminal VSS.

[0123] Here, combined with Figure 10 The timing diagram shown illustrates the core operation process after the addition of the third transistor T3:

[0124] (1) Scan trigger period (t1-t2)

[0125] When the scan signal is high, the fifth transistor T5 is turned on, and the data voltage Vdata is written to intermediate node A. Simultaneously, the third transistor T3 is turned on, pulling the driving node B down to the low-level potential VSS. At this point, the potential difference between intermediate node A and driving node B is Vdata - VSS, meaning the Vgs of the sixth transistor T6 is precisely set to Vdata - VSS. It should be noted that during this stage, the sixth transistor T6 and the third transistor T3 are both turned on. To ensure that driving node B is stably pulled down, the size of the third transistor T3 must be much larger than that of the sixth transistor T6.

[0126] (2) Scan maintenance period and luminescence phase (after t2)

[0127] After the scan signal goes low, the third transistor T3 turns off, and the driving node B is no longer forcibly pulled down. The driving current generated by the sixth transistor T6 begins to charge the driving node B, causing its potential to rise. Since the second capacitor C2 is connected between the intermediate node A and the driving node B, when the potential of the driving node B changes, the potential of the intermediate node A changes synchronously due to the coupling effect, so that the potential difference between the intermediate node A and the driving node B always remains at Vdata-VSS, that is, the Vgs of the sixth transistor T6 remains constant during the scan maintenance period and the entire light emission phase.

[0128] Therefore, this embodiment establishes a precise initial Vgs during the scan triggering period by adding a third transistor T3, and utilizes the coupling effect of the second capacitor C2 to ensure that the Vgs of the sixth transistor T6 remains Vdata - VSS throughout the scan sustaining period and the entire light emission phase, unaffected by fluctuations in the potential of the driving node B. Compared to Figure 8 The pixel circuit 100 shown relies solely on absolute voltage to control grayscale. This embodiment achieves precise control of the driving transistor Vgs, effectively eliminating the influence of driving node B potential changes on the driving current, making pixel control more accurate, and is especially beneficial for image quality performance in low grayscale displays.

[0129] It is worth noting that the above Figure 8 and Figure 9 The pixel circuits 100 shown do not consider pixel compensation processes. When using external compensation schemes, detection is usually required during the blanking period. However, since the EOA and GOA of this application share a continuously output clock signal (CK), the CK width cannot be further widened during the blanking period, thus detection cannot be completed during the traditional blanking period. To solve this problem, this embodiment... Figure 9 Based on this, a fourth transistor T4 is added to transfer the detection process to the scanning stage (i.e., the non-light-emitting stage), so as to achieve accurate detection of the characteristics of the driving transistor without affecting the normal display.

[0130] Specifically, such as Figure 11 As shown, the pixel circuit 100 further includes: a fourth transistor T4, the control terminal of the fourth transistor T4 is connected to the detection control line Sen1, the first terminal of the fourth transistor T4 is connected to the driving node B, and the second terminal of the fourth transistor T4 is connected to the detection acquisition line Sen2.

[0131] Sen1, the detection control line, is an additional scan signal line, independent of the existing scan line Gate. Therefore, the addition of the fourth transistor T4 does not affect... Figure 8 and Figure 9 The working mechanism of the original modules remains unchanged, and the functions of the light-emitting control module 130 and the switching module 140 remain the same. The requirements and waveform control logic of GOA and EOA are also the same. Here, combined with Figure 12 The timing diagram shown illustrates the detection process of the pixel circuit 100 in this embodiment as follows:

[0132] (1) Detection trigger (time t1): When it is necessary to detect the pixels in the nth row, this frame controls the detection control line Sen1 to output a valid detection control signal only when the Gate of the nth row scan line outputs a valid scan signal, and the Sen1 of the detection control line of the other rows outputs an invalid detection control signal; the waveform width of the valid potential of the detection control signal needs to cover the time period from t1 to t6, that is, cover the entire scanning stage.

[0133] (2) Detection period (t2-t6): During the period from t2 to t6, the scanning signal has become low level, and the fifth transistor T5 and the third transistor T3 have been turned off; the detection control signal remains valid, the fourth transistor T4 is turned on, and a path is formed between the driving node B and the detection acquisition line Sen2.

[0134] At this point, the Vgs of the sixth transistor T6 has been precisely controlled to Vdata - VSS through the coupling mechanism, and is in a controlled and stable state. By detecting the voltage or current of the driving node B through the detection acquisition line Sen2, the characteristic parameters of the sixth transistor T6 (such as threshold voltage, mobility, etc.) can be fed back.

[0135] (3) Detection method: During the detection process, the current can be detected by controlling the voltage of the detection acquisition line Sen2, or the voltage can be detected by controlling the current of the detection acquisition line Sen2. Both methods can achieve accurate feedback of the characteristics of the driving transistor. This embodiment does not limit this.

[0136] Therefore, by adding a fourth transistor T4, this embodiment shifts the detection process of external compensation from the traditional blanking period to the scanning phase (t2-t6 period). Without increasing the blanking period or changing the CK clock output width, it achieves accurate detection of the characteristics of the driving transistor, providing data support for subsequent accurate compensation and further improving the long-term stability and image quality consistency of the display panel.

[0137] In one embodiment, this application provides a pixel driving method, specifically including the following embodiments:

[0138] Figure 13 The diagram shown is a flowchart of a pixel driving method provided in an embodiment of this application; as follows: Figure 13 As shown, this pixel driving method is applied to the pixel circuit shown in the above embodiment, and specifically includes the following steps:

[0139] Step S100: During the scanning phase, the pixel driving module outputs driving current to the driving node; and the light emission control module controls the switch module to disconnect the driving node from the light emission module.

[0140] Step S200: During the light-emitting stage, the light-emitting control module controls the switch module to connect the drive node and the light-emitting module, so that the drive current drives the light-emitting module to emit light.

[0141] In one embodiment, the light emission control module includes a reset unit, a charging unit, and an energy storage unit; controlling the switch module to disconnect the drive node from the light emission module through the light emission control module includes: during the scan trigger period of the scan phase, the reset unit responds to the effective potential of the scan signal and pulls the control node down to a low potential; and the energy storage unit keeps the control node at a low potential throughout the scan phase so that the switch module is in an off state.

[0142] In one embodiment, controlling the connection between the switching module and the light-emitting module by the light-emitting control module includes: during the light-emitting control period of the light-emitting phase, charging the control node to a high potential by responding to the effective potential of the light-emitting control signal by the charging unit; and maintaining the control node at a high potential throughout the light-emitting phase by the energy storage unit, so that the switching module is in the conducting state.

[0143] In one embodiment, the pixel circuit includes a fourth transistor, and the pixel driving method further includes: during the detection period of the scanning phase, while the scan line outputs an invalid scan signal, the detection control line outputs an valid detection control signal to control the fourth transistor to be turned on, so that the characteristic parameters of the driving transistor can be obtained through the detection acquisition line.

[0144] It should be noted that the working principle of the pixel driving method provided in this embodiment is the same as that of the pixel circuit in the above embodiment, and will not be repeated here.

[0145] In one embodiment, this embodiment provides a display panel, which includes multiple scan lines, multiple data lines, and multiple light emission control lines. The display panel also includes an array of pixel circuits, which are electrically connected to the scan lines, data lines, and light emission control lines respectively.

[0146] Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0147] In the description of this specification, references to terms such as "some embodiments," "exemplarily," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. The illustrative expressions of the above terms in this specification do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0148] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application. Therefore, any changes or modifications made in accordance with the claims and description of this application should fall within the scope of this patent application.

Claims

1. A pixel circuit, characterized in that, The pixel circuit includes: The pixel driving module, which is connected to the scan line, the data line and the driving node respectively, is configured to: during the scanning phase, in response to the scan signal on the scan line and the data signal on the data line, output a corresponding driving current to the driving node; The light-emitting module is configured to emit light of a corresponding brightness in response to the driving current; The light emission control module, connected to the scan line, the light emission control line, and the control node respectively, is configured to: in response to the triggering of the scan signal, cause the control node to be at an invalid potential during the scanning phase; and under the triggering of the light emission control signal on the light emission control line, cause the control node to be at an effective potential during the light emission phase; wherein the waveform of the light emission control signal is the same as the waveform of the scan signal, and there is a preset phase difference between the light emission control signal and the scan signal; A switching module, connected to the control node, the driving node, and the light-emitting module respectively, is configured to control the on / off connection between the driving node and the light-emitting module based on the potential on the control node.

2. The pixel circuit according to claim 1, characterized in that, The light emission control module includes: A reset unit, connected to the scan line and the control node respectively, is configured to pull the control node down to a low potential in response to the effective potential of the scan signal. The charging unit, which is connected to the light-emitting control line and the control node respectively, is configured to transmit the light-emitting control signal to the control node in response to the effective potential of the light-emitting control signal. An energy storage unit, connected to the control node, is configured to store the potential of the control node.

3. The pixel circuit according to claim 2, characterized in that, The reset unit includes: The first transistor has a control terminal connected to the scan line, a first terminal connected to the control node, and a second terminal connected to a low-level terminal.

4. The pixel circuit according to claim 2, characterized in that, The charging unit includes: The second transistor has its control terminal connected to the light-emitting control line, its first terminal connected to its control terminal, and its second terminal connected to the control node.

5. The pixel circuit according to any one of claims 1-4, characterized in that, The pixel circuit also includes: The third transistor has a control terminal connected to the scan line, a first terminal connected to the driving node, and a second terminal connected to a low-level terminal.

6. The pixel circuit according to claim 5, characterized in that, The pixel circuit also includes: The fourth transistor has its control terminal connected to the detection control line, its first terminal connected to the driving node, and its second terminal connected to the detection acquisition line.

7. A pixel driving method, characterized in that, The pixel driving method, applied to the pixel circuit according to any one of claims 1-6, comprises: During the scanning phase, the pixel driving module outputs a driving current to the driving node; and the light emission control module controls the switching module to disconnect the driving node from the light emission module. During the light-emitting stage, the light-emitting control module controls the switch module to connect the driving node and the light-emitting module, so that the driving current drives the light-emitting module to emit light.

8. The pixel driving method according to claim 7, characterized in that, The light-emitting control module includes a reset unit, a charging unit, and an energy storage unit; the light-emitting control module controls the switching module to disconnect the drive node from the light-emitting module, including: During the scan triggering period of the scan phase, the control node is pulled down to a low potential by the reset unit in response to the effective potential of the scan signal; and the energy storage unit keeps the control node at a low potential throughout the scan phase so that the switching module is in the off state. The light-emitting control module controls the switch module to connect the driving node to the light-emitting module, including: During the light-emitting control period of the light-emitting phase, the control node is charged to a high potential by the effective potential of the light-emitting control signal in response to the charging unit; and the control node is kept at a high potential throughout the light-emitting phase by the energy storage unit, so that the switching module is in the conducting state.

9. The pixel driving method according to claim 7, characterized in that, The pixel circuit includes a fourth transistor, and the pixel driving method further includes: During the detection period of the scanning phase, while the scan line outputs an invalid scan signal, the detection control line outputs a valid detection control signal to control the fourth transistor to turn on, so that the characteristic parameters of the driving transistor can be obtained through the detection acquisition line.

10. A display panel, the display panel comprising multiple scan lines, multiple data lines, and multiple light-emitting control lines, characterized in that, The display panel also includes: The pixel circuit according to any one of claims 1-6 is arranged in an array, wherein the pixel circuit is electrically connected to the scan line, the data line and the light emission control line respectively.

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