A display control circuit, a display panel and a display device

Abstract

The application provides a display control circuit, a display panel and a display device. The display control circuit comprises a plurality of pixel units and a driving unit. The pixel unit comprises an anode signal input end, a cathode signal input end and a light emitting element. The light emitting element is arranged between the anode signal input end and the cathode signal input end. The driving unit has a first signal end and a second signal end. The voltage of the first signal end is in a correlation relationship with the voltage of the cathode signal input end. The second signal end is connected with the anode signal input end. The driving unit is configured to output a reset signal through the second signal end based on the voltage of the first signal end in a non-light emitting stage. The reset signal is used to initialize the anode voltage of the anode signal input end. The reset signal can also change along with the voltage change of the cathode signal input end, which is beneficial to reduce the delay between the reset signal and the voltage of the cathode signal input end, and further beneficial to improve the display stability of the pixel unit.

Description

Technical Field

[0001] This application belongs to the field of display technology, and in particular relates to a display control circuit, a display panel, and a display device. Background Technology

[0002] Active-matrix organic light-emitting diode (AMOLED) and flat panel display devices based on light-emitting diode (LED) technologies are widely used in various consumer electronics products such as mobile phones, televisions, laptops, and desktop computers due to their advantages such as high image quality, power saving, thin body and wide range of applications, becoming the mainstream of display devices.

[0003] However, the performance of current display products needs to be improved. Summary of the Invention

[0004] The purpose of this application is to provide a display control circuit, a display panel, and a display device, which aims to solve the problem of low performance of display products in traditional technology.

[0005] A first aspect of this application provides a display control circuit, comprising:

[0006] A plurality of pixel units are provided, each pixel unit including an anode signal input terminal, a cathode signal input terminal, and a light-emitting element, the light-emitting element being disposed between the anode signal input terminal and the cathode signal input terminal; each pixel unit has a light-emitting phase and a non-light-emitting phase, in the light-emitting phase the light-emitting element is electrically connected to the anode signal input terminal and the cathode signal input terminal, and in the non-light-emitting phase at least one of the anode signal input terminal and the cathode signal input terminal is disconnected from the light-emitting element;

[0007] The driving unit has a first signal terminal and a second signal terminal, the voltage of the first signal terminal is related to the voltage of the cathode signal input terminal, and the second signal terminal is connected to the anode signal input terminal;

[0008] The driving unit is configured to output a reset signal based on the voltage of the first signal terminal and through the second signal terminal during the non-light-emitting phase. The reset signal is used to initialize the anode voltage of the anode signal input terminal.

[0009] In some embodiments of this application, the first signal terminal is used to connect to an external cathode signal together with the cathode signal input terminal.

[0010] In some embodiments of this application, the second signal terminal is connected between the anode signal input terminal and the light-emitting element.

[0011] In some embodiments of this application, the plurality of pixel units include a first color pixel subunit, a second color pixel subunit, and a third color pixel subunit. The second signal terminal is configured to be a plurality of such terminals, and the plurality of second signal terminals include a first signal subunit, a second signal subunit, and a third signal subunit. The first signal subunit is used to output a first reset signal to the anode signal input terminal of the first color pixel subunit. The second signal subunit is used to output a second reset signal to the anode signal input terminal of the second color pixel subunit. The third signal subunit is used to output a third reset signal to the third color pixel subunit.

[0012] When the plurality of pixel units are in a low-brightness state, the signal value of at least one of the first reset signal, the second reset signal, and the third reset signal is different from the signal value of at least another of the first reset signal, the second reset signal, and the third reset signal.

[0013] In some embodiments of this application, the first color pixel subunit, the second color pixel subunit, and the third color pixel subunit are respectively selected from one of the red pixel subunit, the blue pixel subunit, and the green pixel subunit.

[0014] In some embodiments of this application, the first color pixel subunit is a red pixel subunit or a green pixel subunit, the second color pixel subunit is a blue pixel subunit, and when the plurality of pixel units are in a low brightness state, the signal value of the first reset signal is lower than the signal value of the second reset signal.

[0015] In some embodiments of this application, when the plurality of pixel units are in a low brightness state, the signal value U1 of the first reset signal and the signal value U2 of the second reset signal satisfy the following condition: U2 = U1 + 0.2v.

[0016] In some embodiments of this application, the driving unit includes a low-dropout linear regulator, which is used to output the first reset signal and the second reset signal.

[0017] A third aspect of this application also provides a display panel, the display panel including the display control circuit described above.

[0018] A third aspect of this application also provides a display device, the display device including the display panel described above.

[0019] The beneficial effects of the embodiments of the present invention compared with the prior art are as follows: The above-mentioned display control circuit, display panel and display device include multiple pixel units and driving units; the pixel unit includes an anode signal input terminal, a cathode signal input terminal and a light-emitting element, the light-emitting element being disposed between the anode signal input terminal and the cathode signal input terminal; the pixel unit has a light-emitting stage and a non-light-emitting stage, in the light-emitting stage the light-emitting element is electrically connected to the anode signal input terminal and the cathode signal input terminal, in the non-light-emitting stage at least one of the anode signal input terminal and the cathode signal input terminal is disconnected from the light-emitting element; the driving unit has a first signal terminal and a second signal terminal, the voltage of the first signal terminal is correlated with the voltage of the cathode signal input terminal, and the second signal terminal is connected to the anode signal input terminal; the driving unit is configured to output a reset signal based on the voltage of the first signal terminal and through the second signal terminal in the non-light-emitting stage, the reset signal being used to initialize the anode voltage of the anode signal input terminal; that is, the voltage of the first signal terminal can change with the voltage change of the cathode signal input terminal, so the reset signal can also change with the voltage change of the cathode signal input terminal, which is beneficial to reducing the delay between the reset signal and the voltage of the cathode signal input terminal, and thus beneficial to improving the display stability of the pixel unit. Attached Figure Description

[0020] Figure 1 A schematic diagram of the framework structure of a display control circuit provided in an embodiment of this application;

[0021] Figure 2 A schematic diagram of a pixel circuit provided in an embodiment of this application;

[0022] Figure 3 A schematic diagram of the frame structure of a display control circuit provided in another embodiment of this application;

[0023] Figure 4 A schematic diagram of the frame structure of a display control circuit provided in another embodiment of this application;

[0024] Figure 5 A schematic diagram of the framework structure of a display control circuit provided in another embodiment of this application;

[0025] Figure 6 This is a schematic diagram of the circuit structure of a pixel circuit provided in an embodiment of this application.

[0026] Specific element symbol explanations: 100-pixel unit, 110-light-emitting element, 120-anode signal input terminal, 130-cathode signal input terminal, 140-first color pixel sub-unit, 150-second color pixel sub-unit, 160-third color pixel sub-unit, 200-driving unit, Vref2-reset signal. Detailed Implementation

[0027] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0028] It should be noted that when a component is referred to as being "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0029] It should be understood that the terms "length", "width", "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0030] Furthermore, the terms "first" and "second" 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. Thus, a feature defined as "first" or "second" 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.

[0031] It's important to know that with the rapid development of display technology, OLED (Organic Light Emitting Diode) display panels, with their numerous advantages such as self-illumination, high contrast, wide viewing angle, and fast response speed, have been widely used in many fields, including smartphones, tablets, televisions, and automotive displays. In OLED display panels, the performance of the pixel circuitry directly determines the quality of the display, and during the reset phase, the charge at the OLED anode signal input terminal needs to be neutralized.

[0032] In OLED display panels, parasitic capacitance exists at the anode signal input terminal. Whenever the displayed image changes, i.e., during the transition from one image frame to the next, a certain amount of charge remains on the anode signal input terminal. This residual charge affects the turn-on speed of the pixel unit after reset. Different pixel units exhibit different turn-on speeds due to variations in the residual charge at their anode signal input terminals.

[0033] For example, when displaying a uniformly colored image, multiple pixels that should light up simultaneously and with consistent brightness may exhibit inconsistent brightness due to differences in residual anode charge. Some pixels may light up quickly, while others may light up slowly, severely disrupting the consistency of the pixel circuitry and resulting in subtle but perceptible flickering or uneven brightness in the displayed image. Taking common pixel circuit architectures like 7T1C / 8T1C as an example, when the reset voltage driving force used to neutralize the anode charge is insufficient, excess charge on the anode cannot be neutralized promptly and adequately. This manifests in the displayed image as localized color deviations and abnormal brightness, significantly reducing the overall display quality.

[0034] In related technologies, the cathode voltage of a pixel unit is externally input, but this externally input cathode voltage changes frequently. For example, in scenarios involving rapid screen switching or displaying high dynamic range content, the cathode voltage may undergo significant changes within a short period. However, display driver chips typically output a reset signal to the anode signal input of the pixel unit based on an internal negative voltage. Due to the delay in the display driver chip's response, the anode reset effect is delayed. If excessive charge has already accumulated on the anode, a large amount of charge is released instantaneously during the cathode voltage switch, causing brightness fluctuations on the display panel. This severely disrupts the smoothness and stability of the image in dynamic display scenarios such as watching videos and playing games, greatly affecting the user's visual experience and potentially causing eye strain.

[0035] Based on this, this application improves the related display control circuit, display panel, and display device.

[0036] Please see Figure 1 and Figure 2 , Figure 1 A schematic diagram of the frame structure of the display control circuit in this embodiment is shown; Figure 2This embodiment shows a schematic diagram of the pixel circuit structure. In this embodiment, the light-emitting element 110 is an OLED device, the anode signal input terminal 120 is VDD, and the cathode signal input terminal 130 is VSS. The display control circuit of this embodiment includes multiple pixel units 100 and a driving unit 200. Each pixel unit 100 includes an anode signal input terminal 120, a cathode signal input terminal 130, and a light-emitting element 110. The light-emitting element 110 is disposed between the anode signal input terminal 120 and the cathode signal input terminal 130. The pixel unit 100 has a light-emitting stage and a non-light-emitting stage. In the light-emitting stage, the light-emitting element 110 and the anode... Signal input terminal 120 is electrically connected to cathode signal input terminal 130. During the non-light-emitting stage, at least one of anode signal input terminal 120 and cathode signal input terminal 130 is disconnected from light-emitting element 110. Driving unit 200 has a first signal terminal and a second signal terminal. The voltage of the first signal terminal is correlated with the voltage of cathode signal input terminal 130, and the second signal terminal is connected to anode signal input terminal 120. Driving unit 200 is configured to output a reset signal Vref2 based on the voltage of the first signal terminal and through the second signal terminal during the non-light-emitting stage. The reset signal Vref2 is used to initialize the anode voltage of anode signal input terminal 120.

[0037] It should be explained that the pixel unit 100 is a fundamental component of the display control circuit and the smallest functional unit for realizing image display. Anode signal input terminal 120: provides the anode voltage to the light-emitting element 110 within the pixel unit 100. Cathode signal input terminal 130: provides the cathode voltage to the light-emitting element 110 within the pixel unit 100. The light-emitting element 110 is the component in the pixel unit 100 that performs the light-emitting function, such as a light-emitting diode. During the light-emitting phase, the light-emitting element 110 emits light; during the non-light-emitting phase, the light-emitting element 110 does not emit light.

[0038] Understandably, during the operation of the display control circuit, the pixel unit 100 continuously switches between the light-emitting stage and the non-light-emitting stage to achieve stable and high-quality image display. When the pixel unit 100 is in the light-emitting stage, the light-emitting element 110 establishes an electrical connection with the anode signal input terminal 120 and the cathode signal input terminal 130. At this time, current flows smoothly from the anode signal input terminal 120, passes through the light-emitting element 110, and flows out from the cathode signal input terminal 130. Under the action of the current, electrons and holes inside the light-emitting element 110 recombine, thereby generating photons and emitting light. Different pixel units 100 can display different brightness and colors by controlling the magnitude of the current passing through the light-emitting element 110, thus forming rich and colorful images.

[0039] When pixel unit 100 enters the non-light-emitting stage, the connection between at least one of the anode signal input terminal 120 and the cathode signal input terminal 130 and the light-emitting element 110 is broken, and current can no longer flow through the light-emitting element 110, causing the light-emitting element 110 to stop emitting light. During this stage, since the voltage at the first signal terminal can change with the voltage at the cathode signal input terminal 130, the driving unit 200 outputs a reset signal Vref2 through the second signal terminal based on the voltage at the first signal terminal. This reset signal Vref2 recalibrates and initializes the anode voltage at the anode signal input terminal 120. This ensures that pixel unit 100 can quickly and stably enter the working state when the next light-emitting stage arrives, which improves the display stability of pixel unit 100, making the displayed image more stable and clear, and reducing problems such as flickering and color deviation.

[0040] In current display control circuits, a delay exists between the reset signal Vref2 and the cathode signal of the pixel circuit, which can lead to display defects. However, in this embodiment, on the one hand, the anode voltage of the anode signal input terminal 120 is initialized during the non-light-emitting phase, ensuring that each pixel unit 100 has a stable starting voltage when entering the light-emitting phase. This avoids uneven light emission caused by accumulated errors or instability in the anode voltage, improving the stability and consistency of the displayed image. On the other hand, since the reset signal Vref2 is output based on the voltage of the first signal terminal, and the voltage of the first signal terminal is related to the voltage of the cathode signal input terminal 130, the voltage of the first signal terminal can change with the voltage change of the cathode signal input terminal 130. Therefore, the reset signal Vref2 can also change with the voltage change of the cathode signal input terminal 130. That is, the anode voltage reset value can be dynamically adjusted in real time according to the cathode voltage change, which helps to reduce the delay between the reset signal Vref2 and the voltage of the cathode signal input terminal 130, thereby improving the display stability of the pixel unit 100.

[0041] In some embodiments, the light-emitting element 110 is a light-emitting diode, with the positive terminal of the light-emitting diode connected to the anode signal input terminal 120 and the negative terminal of the light-emitting diode connected to the cathode signal input terminal 130.

[0042] In some embodiments of this application, please refer to Figure 3 , Figure 3 A schematic diagram of the display control circuit framework of this embodiment is shown; the first signal terminal of this embodiment is used to connect to the external cathode signal together with the cathode signal input terminal 130.

[0043] Understandably, when the external cathode signal changes, the voltages at the two input terminals will change synchronously. This close voltage correlation allows the driving unit 200 to more accurately and quickly output a reset signal Vref2 through the second signal terminal based on the voltage change at the first signal terminal during the non-light-emitting phase, further reducing the delay between the reset signal Vref2 and the voltage at the cathode signal input terminal 130. This not only improves the display stability of the pixel unit 100 but also optimizes the display effect, ensuring that the brightness and color of the image remain stable and reducing display abnormalities caused by voltage delay.

[0044] Please refer to the embodiments described in this application. Figure 2 In this embodiment, the second signal terminal is connected between the anode signal input terminal 120 and the light-emitting element 110.

[0045] Understandably, during the non-light-emitting phase of pixel unit 100, driving unit 200 outputs a reset signal Vref2 through the second signal terminal. Since it is located between the anode signal input terminal 120 and the light-emitting element 110, the reset signal Vref2 can directly act on the anode signal input terminal 120, efficiently initializing the anode voltage. Compared to other connection methods, this direct connection reduces the signal transmission path, avoiding signal loss and interference during long-distance transmission, allowing the reset signal Vref2 to adjust the anode voltage more accurately and quickly. During the light-emitting phase, a stable anode voltage ensures that the light-emitting element 110 receives a stable driving current, making the light emission of the light-emitting element 110 more stable, thereby improving the display stability of the entire pixel unit 100, reducing the probability of flickering, uneven brightness, and other problems in the displayed image, and improving display quality.

[0046] In some embodiments of this application, please refer to Figure 4 , Figure 4 A schematic diagram of the display control circuit framework of this embodiment is shown. The plurality of pixel units 100 in this embodiment include a first color pixel subunit 140, a second color pixel subunit 150, and a third color pixel subunit. Multiple second signal terminals are provided, each including a first signal sub-terminal, a second signal sub-terminal, and a third signal sub-terminal. The first signal sub-terminal outputs a first reset signal to the anode signal input terminal 120 of the first color pixel subunit 140. The second signal sub-terminal outputs a second reset signal to the anode signal input terminal 120 of the second color pixel subunit 150. The third signal sub-terminal outputs a third reset signal to the third color pixel subunit. When the plurality of pixel units 100 are in a low-brightness state, the signal value of at least one of the first, second, and third reset signals is different from the signal value of at least another of the first, second, and third reset signals.

[0047] It's important to understand that in low-brightness display scenarios, the display panel mixes colors to create rich hues by controlling the luminous intensity of the red, green, and blue sub-pixels within each pixel. However, the red, green, and blue OLED materials themselves have inherent inconsistencies. When different colored OLED sub-pixels are reset using the same reset conditions—that is, a fixed charge neutralization rate and time—their post-reset turn-on speeds will exhibit significant asynchrony. This inconsistency in turn-on speeds may cause the red sub-pixel to reach its set brightness first, while the green and blue sub-pixels catch up later, or vice versa. This directly leads to a severe decrease in the uniformity of the display panel at low brightness, resulting in noticeable color and brightness unevenness in the image. This phenomenon is particularly pronounced when using devices like mobile phones at night, significantly interfering with the user's visual experience and reducing product comfort.

[0048] It is understood that in this embodiment, different reset signals Vref2 are selected for different color pixel sub-units. Since each color pixel sub-unit can obtain a reset signal Vref2 suitable for its own characteristics, its light-emitting element 110 can emit light more stably and efficiently during the light-emitting stage. This helps to improve the color accuracy and brightness uniformity of the displayed image, avoids problems such as color deviation and uneven brightness caused by inconsistent light emission from different color pixels, and makes the entire displayed image clearer, more vivid, and more realistic.

[0049] In some embodiments of this application, the first color pixel subunit 140, the second color pixel subunit 150, and the third color pixel subunit 160 are respectively selected from one of the red pixel subunit, the blue pixel subunit, and the green pixel subunit.

[0050] Understandably, when the first color pixel subunit 140 is a red pixel subunit, the first reset signal output from the first signal sub-terminal will set its signal value according to the characteristics of the red light-emitting element 110 to ensure that the anode voltage of the red pixel subunit can be accurately initialized, enabling the red light-emitting element 110 to emit red light stably and efficiently during the light-emitting phase. Similarly, if the second color pixel subunit 150 is a blue pixel subunit, the second reset signal output from the second signal sub-terminal will determine its signal value according to the characteristics of the blue light-emitting element 110 to ensure that the anode voltage of the blue pixel subunit meets the operating requirements of the blue light-emitting element 110.

[0051] In some embodiments of this application, the first color pixel subunit 140 is a red pixel subunit or a green pixel subunit, and the second color pixel subunit 150 is a blue pixel subunit. When multiple pixel units are in a low-brightness state, the signal value of the first reset signal is lower than the signal value of the second reset signal.

[0052] Understandably, in display technology, the physical and chemical properties of red, green, and blue light-emitting elements 110 differ significantly. Generally, the luminous efficiency of blue light-emitting elements 110 is lower than that of red and green light-emitting elements 110, and they require higher driving voltages to achieve the same brightness. Specifically, compared to red and green light-emitting elements 110, blue light-emitting elements 110 have lower luminous efficiency and require higher driving voltages to achieve brightness similar to red and green light-emitting elements 110. This is determined by the light-emitting materials they each employ. For example, red and green light-emitting materials can generate sufficient electron-hole recombination at lower voltages to emit light of their respective colors; while the energy level structure of blue light-emitting materials requires higher energy (i.e., higher voltage) to excite electron transitions and thus achieve light emission. Therefore, to ensure that pixel sub-units of different colors can operate normally and efficiently, different reset signals Vref2 need to be set according to their characteristics.

[0053] When the first color pixel subunit 140 is a red or green pixel subunit, the first reset signal value output by the first signal sub-terminal is low. This low reset signal Vref2 can initialize the anode voltage of the red or green pixel subunit to a suitable low level. In the subsequent light-emitting stage, this suitable anode voltage allows the red or green light-emitting element 110 to achieve stable light emission with low power consumption, while also avoiding problems such as shortened lifespan of the light-emitting element 110 due to excessive voltage. The second signal sub-terminal outputs a second reset signal with a higher signal value to the anode signal input terminal 120 of the blue pixel subunit. This higher reset signal Vref2 can initialize the anode voltage of the blue pixel subunit to a higher level to meet the high-energy excitation requirements of the blue light-emitting element 110. In this way, during the light-emitting stage, the blue light-emitting element 110 can obtain sufficient driving voltage, thereby emitting blue light with sufficient brightness and color purity. This can significantly improve the color accuracy and brightness uniformity of the displayed image. Pixel subunits of different colors can all undergo anode voltage initialization under the action of the reset signal Vref2 suitable for their own characteristics, so that the red, green, and blue light-emitting elements 110 can emit light stably and efficiently. This helps avoid problems such as color deviation and uneven brightness caused by inconsistent emission from different colored pixels.

[0054] In some embodiments of this application, when multiple pixel units 100 are in a low-brightness state, the signal value U1 of the first reset signal and the signal value U2 of the second reset signal satisfy the following condition: U2 = U1 + 0.2v.

[0055] It is understood that in the embodiments of this application, the signal values ​​U1 of the first reset signal and U2 of the second reset signal are limited. When the above conditions are met, whether it is a static picture or a dynamic video, the blue pixel sub-unit can emit blue light with the expected brightness and color saturation under the action of U2, and work together with the red and green pixel sub-units to present a realistic color effect.

[0056] In some embodiments of this application, please refer to Figure 5 , Figure 5 A schematic diagram of the display control circuit provided in this embodiment is shown; the driving unit 200 in this embodiment includes a low-dropout linear regulator, which is used to output a first reset signal and a second reset signal.

[0057] It should be explained that a low-dropout regulator (LPO) is a commonly used power management chip whose main function is to convert the input voltage into a stable output voltage. In this display control circuit, it converts the input power supply voltage into a reset signal Vref2 that meets the requirements of different color pixel sub-units. Since the first color pixel sub-unit 140 (such as a red or green pixel sub-unit) and the second color pixel sub-unit 150 (blue pixel sub-unit) require different reset signal values ​​for Vref2 (e.g., U2 = U1 + 0.2V), the low-dropout regulator, with its stable voltage regulation capability, can accurately output the required first and second reset signals.

[0058] Understandably, compared to other voltage regulation methods, low-dropout linear regulators have advantages such as low dropout and low output voltage ripple. The low dropout characteristic means that it consumes less voltage when converting input voltage to output voltage, which helps improve the energy efficiency of the entire drive unit 200 and reduce power consumption. Low output voltage ripple ensures the stability of the reset signal Vref2, reducing the impact of voltage fluctuations on the initialization of the pixel sub-unit anode voltage. If the reset signal Vref2 has large ripple, it may cause instability in the anode voltage of the pixel sub-unit during initialization, thus affecting the light-emitting effect of the light-emitting element 110 and causing problems such as brightness flicker and color deviation. The stable reset signal Vref2 output by the low-dropout linear regulator ensures that the anode voltage of each pixel sub-unit can be accurately initialized during the non-light-emitting stage, providing a stable voltage foundation for the subsequent light-emitting stage, thereby improving the stability and color accuracy of the displayed image and optimizing display quality.

[0059] Please continue reading. Figure 5In the diagram, the external ELVSS is the externally input cathode signal. ELVSS typically refers to an external reference voltage source, such as a negative voltage reference, providing a basic voltage reference for the entire circuit. Vref2_1, Vref2_2, and Vref2_3 are reference signals output by the driving unit 200 to multiple pixel units 100, specifically the reset signal Vref2 after LDO adjustment. They originate from the driving unit 200 and are connected to multiple pixel units 100 respectively, used to provide reset signals Vref2 for different color pixel sub-units, initialize the anode voltage of the pixel unit 100, and perform other operations to achieve stable light emission control.

[0060] The specific process is as follows: The external ELVSS supplies power to the driving unit 200. The LDO inside the driving unit 200 processes the input voltage to generate stable reference signals (such as Vref2_1, Vref2_2, and Vref2_3). These reference signals are sent to multiple pixel units 100 to control the working state of the light-emitting elements 110 in the pixel units 100. For example, the anode voltage is reset and initialized during the non-light-emitting stage, thereby achieving stable and high-quality image display.

[0061] Please see Figure 6 , Figure 6 A schematic diagram of the pixel circuit provided in this embodiment is shown; Figure 6 Taking an 8T1C circuit as an example, VDD is the anode signal input terminal 120, VSS is the cathode signal input terminal 130, and OLED is the light-emitting element 110. The pixel circuit includes a first transistor M1, a second transistor M2, a third transistor M3, a fourth transistor M4, a fifth transistor M5, a sixth transistor M6, a seventh transistor M7, and an eighth transistor M8.

[0062] The pixel circuit of this application embodiment includes a writing stage, a light-emitting stage, and a non-light-emitting stage.

[0063] During the writing phase, Vdata (data signal) carries the information needed to display the image. When the scan signal SP1 is active, transistor M2 is turned on, allowing the Vdata signal to enter the circuit. At this time, the Vdata signal charges capacitor Cst, which stores the charge related to the display information. This charge will determine the subsequent light emission state of the OLED.

[0064] During the light-emitting phase, the OLED emits light when the enable signal EM is active. At this time, transistors M5 and M6 are turned on, and current flows from VDD through transistors M5 and M6 to the OLED. As the current passes through the OLED, electrons and holes recombine, generating photons and thus emitting light. The brightness and color characteristics of the emitted light are determined by factors such as the Vdata signal previously stored on the Cst capacitor and the reference voltage in the circuit. For example, the Vdata signal determines the amount of charge stored on the Cst capacitor, which in turn affects the magnitude of the current flowing through the OLED, ultimately determining the brightness of the OLED's emission.

[0065] During the non-light-emitting phase, the control signal turns off transistors M5 and M6, cutting off the current path to the OLED, and the OLED stops emitting light. The driving unit 200 uses signals such as Vref2 to reset and initialize the anode voltage. At this time, transistor M7 is turned on, and the Vref2 signal acts on the relevant nodes to adjust the anode voltage to a suitable initial value, preparing for the next light-emitting phase.

[0066] Specifically, when the red, blue, and green pixel sub-units (RGB pixel sub-units) all use the same reset signal Vref2, especially under low-brightness conditions, the turn-on speeds of these sub-units after the OLED anode reset in the pixel circuit are inconsistent, resulting in a uniform decrease in display brightness at low levels. This is because the amount of charge accumulated at the anode signal receiver of different color pixel sub-units varies, so some color pixel sub-units with a larger amount of charge may be brighter, especially noticeable under low-brightness conditions.

[0067] However, in this embodiment, the negative voltage source of the reset signal Vref2 is adjusted to an external cathode signal. The driving unit 200 uses the external cathode signal to generate multiple anode reset signals Vref2 through the negative output LDO, and transmits different voltage amplitudes such as Vref2_1, Vref2_2, and Vref2_3 to the RGB pixel circuit of the display panel. The R, G, and B pixels in the display panel no longer use the same anode reset signal Vref2. The anode reset signal Vref2 corresponding to each color pixel is the same. The generated different anode reset signals Vref2 are connected to the anode reset lines corresponding to the R, G, and B pixels in the display panel, thereby optimizing the problem of the difficulty in turning on the OLED after reset when the blue pixel is low brightness, which causes a decrease in display uniformity.

[0068] Furthermore, in order to better implement the display control circuit in any of the above embodiments, this application also provides a display panel, which includes the above-described display control circuit, based on the display control circuit described above.

[0069] Furthermore, in order to better implement the display panel in any of the above embodiments, this application also provides a display device based on the above display panel, the display device including the above display panel.

[0070] In some embodiments, the display device may be a mobile phone, tablet, desktop computer, laptop computer, wearable device, automotive screen, sensor device, etc.

[0071] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0072] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0073] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0074] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0075] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A display control circuit, characterized in that, include: Multiple pixel units, each pixel unit including an anode signal input terminal, a cathode signal input terminal and a light-emitting element, wherein the light-emitting element is disposed between the anode signal input terminal and the cathode signal input terminal; The pixel unit has a light-emitting stage and a non-light-emitting stage. In the light-emitting stage, the light-emitting element is electrically connected to the anode signal input terminal and the cathode signal input terminal. In the non-light-emitting stage, at least one of the anode signal input terminal and the cathode signal input terminal is disconnected from the light-emitting element. The driving unit has a first signal terminal and a second signal terminal, the voltage of the first signal terminal is related to the voltage of the cathode signal input terminal, and the second signal terminal is connected to the anode signal input terminal; The driving unit is configured to output a reset signal based on the voltage of the first signal terminal and through the second signal terminal during the non-light-emitting phase. The reset signal is used to initialize the anode voltage of the anode signal input terminal.

2. The display control circuit according to claim 1, characterized in that, The first signal terminal is used to connect to an external cathode signal together with the cathode signal input terminal.

3. The display control circuit according to claim 2, characterized in that, The second signal terminal is connected between the anode signal input terminal and the light-emitting element.

4. The display control circuit according to claim 1, characterized in that, The plurality of pixel units include a first color pixel subunit, a second color pixel subunit, and a third color pixel subunit. The second signal terminal is configured to be multiple, and the multiple second signal terminals include a first signal sub-terminal, a second signal sub-terminal, and a third signal sub-terminal. The first signal sub-terminal is used to output a first reset signal to the anode signal input terminal of the first color pixel subunit. The second signal sub-terminal is used to output a second reset signal to the anode signal input terminal of the second color pixel subunit. The third signal sub-terminal is used to output a third reset signal to the third color pixel subunit. When the plurality of pixel units are in a low-brightness state, the signal value of at least one of the first reset signal, the second reset signal, and the third reset signal is different from the signal value of at least another of the first reset signal, the second reset signal, and the third reset signal.

5. The display control circuit according to claim 4, characterized in that, The first color pixel subunit, the second color pixel subunit, and the third color pixel subunit are respectively selected from one of the red pixel subunit, the blue pixel subunit, and the green pixel subunit.

6. The display control circuit according to claim 5, characterized in that, The first color pixel subunit is a red pixel subunit or a green pixel subunit, and the second color pixel subunit is a blue pixel subunit. When the plurality of pixel units are in a low brightness state, the signal value of the first reset signal is lower than the signal value of the second reset signal.

7. The display control circuit according to claim 6, characterized in that, When the plurality of pixel units are in a low brightness state, the signal value U1 of the first reset signal and the signal value U2 of the second reset signal satisfy the following condition: U2 = U1 + 0.2v.

8. The display control circuit according to claim 4, characterized in that, The drive unit includes a low-dropout linear regulator, which is used to output the first reset signal and the second reset signal.

9. A display panel, characterized in that, The display panel includes the display control circuit according to any one of claims 1 to 8.

10. A display device, characterized in that, The display device includes the display panel as described in claim 9.

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