Sub-pixel driving unit, pixel circuit and display panel

Abstract

The application discloses a sub-pixel driving unit, a pixel circuit and a display panel. The sub-pixel driving unit comprises a sub-pixel driver and a sensing circuit. The sensing circuit is configured to perform timing control on a sensing signal, generate digital data corresponding to the sensing signal, and send the digital data to the sub-pixel driver. The sub-pixel driver is configured to receive the digital data, and drive a corresponding sub-pixel to emit light when the sub-pixel needs to emit light based on the digital data. The application can reduce the area of a corresponding driving chip or display panel, thereby reducing the design workload and the corresponding process cost.

Description

Technical Field

[0001] This application relates to the field of OLED display technology, specifically to a sub-pixel driving unit, pixel circuit, and display panel. Background Technology

[0002] OLED (Organic Light Emitting Diode) display panels typically include multiple pixels, each pixel comprising multiple sub-pixels, and each sub-pixel having corresponding sensing lines and drivers. These sensing lines need to be bonded to sensing circuitry and connected accordingly; for example, reference... Figure 1a The circuit structure diagram of the display panel shown is provided below. The drivers for the pixels can be found in the diagram. Figure 1b As shown, Figure 1a In the display panel shown, the sense signal required by each pixel is sent to the corresponding sensing circuit via sensing lines, generating sensing data. This sensing data can be sent to the memory associated with the sensing circuit and stored in the memory of the display driver chip. When the sensing data stored in the memory senses panel data, it is compressed by the corresponding sensing data conversion block. This compressed data is then passed again through the data driving circuit (such as...). Figure 1b The driver (shown) outputs to the panel to display compressed OLED pixels. When the sensing lines corresponding to the sub-pixels need to sense data, adding sensing lines to the OLED panel will increase the area. There are also issues such as additional design of the driver chip interface between the display driver chip and the sensing circuit, which will increase the design workload and manufacturing cost. Summary of the Invention

[0003] In view of this, this application provides a sub-pixel driving unit, a pixel circuit, and a display panel to solve the problem that existing solutions easily lead to increased workload in OLED panel design and increased process costs.

[0004] This application provides a sub-pixel driving unit, including a sub-pixel driver and a sensing circuit; The sensing circuit is used to perform timing control on the sensing signal, generate digital data corresponding to the sensing signal, and send the digital data to the sub-pixel driver. The sub-pixel driver is used to receive the digital data and drive the sub-pixel to emit light when the corresponding sub-pixel needs to emit light based on the digital data.

[0005] Optionally, the digital data includes first digital data and second digital data; the sub-pixel driver includes a first capacitor, a second capacitor, a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, and a ninth transistor; the control terminal of the first transistor is used to receive an n-1 level scan signal, the input terminal is used to receive an initial voltage, and the output terminal is connected to the first electrode of the first capacitor and the control terminal of the fourth transistor; the first electrode of the first capacitor is connected to the input terminal of the fourth transistor, the second electrode is connected to the input terminal of the fifth transistor, and the input terminal of the fifth transistor is used to connect to a first power supply; the control terminal of the second transistor is used to receive an n-1 level scan signal, the input terminal is used to receive a data signal and is connected to the input terminal of the ninth transistor; the control terminal of the third transistor is used to receive an n-1 level scan signal, and the input terminal is connected to the first power supply; The output terminal of the fourth transistor is connected to the control terminal of the fifth transistor; the control terminal of the seventh transistor is used to receive an n-level scan signal, its input terminal is connected to the first electrode of the second capacitor, and its output terminal is connected to the input terminal of the fourth transistor; the control terminal of the eighth transistor is used to receive an n-level scan signal, its input terminal is connected to the second electrode of the second capacitor, and its output terminal is connected to the control terminal of the fourth transistor; the control terminal of the ninth transistor is used to receive second digital data, and its output terminal is connected to the second electrode of the second capacitor; the input terminal of the fourth transistor is connected to the output terminal of the fifth transistor, and its output terminal is connected to the input terminal of the sixth transistor; the control terminals of the sixth transistor and the fifth transistor are respectively used to receive first digital data; the output terminal of the sixth transistor outputs a second power supply to the corresponding sub-pixel, so that the corresponding sub-pixel emits light under the control of the first power supply and the second power supply.

[0006] Optionally, the fourth transistor is an N-channel MOS transistor, and the other transistors in the sub-pixel driver are P-channel MOS transistors.

[0007] Optionally, the first transistor, the second transistor, the third transistor, the seventh transistor, and the eighth transistor are all off when the fourth transistor and the fifth transistor are on, and all are on when the fourth transistor and the fifth transistor are off.

[0008] The pixel circuit provided in this application includes at least one of the above-mentioned seed pixel driving units.

[0009] Optionally, the pixel circuit further includes a sub-pixel light-emitting unit; the sub-pixel driving unit is used to drive at least one of the sub-pixel light-emitting units to emit light.

[0010] This application provides a display panel that includes any of the pixel circuits described above.

[0011] The sub-pixel driving unit, pixel circuit, and display panel described in this application use a sensing circuit to perform timing control on the sensing signal, generating digital data corresponding to the sensing signal. This digital data can control the sub-pixel driver in real time, so that the sub-pixel driver can drive the corresponding sub-pixel to emit light based on the digital data. Specifically, it can compensate in real time when the corresponding sub-pixel needs to emit light and the display needs to be turned on, so that the sub-pixel driver can drive the corresponding sub-pixel to emit light. The entire driving process does not require additional storage or sensing data compression modules, so that the corresponding display panel does not need to set up storage modules and sensing data compression modules, etc. It can also simplify the relevant interface settings, thereby reducing the area of ​​the corresponding driving chip or display panel, thereby reducing the design workload and reducing the corresponding process cost. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1a This is a schematic diagram of the circuit structure of the display panel; Figure 1b This is a schematic diagram of the driver structure; Figure 2 This is a schematic diagram of the sub-pixel driving unit structure according to an embodiment of this application; Figure 3 This is a schematic diagram of a sub-pixel driver structure according to an embodiment of this application; Figure 4a and Figure 4b This is a schematic diagram showing the correspondence between the sub-pixel driving unit and the sub-pixel light-emitting unit in one embodiment of this application; Figure 5 This is a schematic diagram of a pixel unit according to an embodiment of this application. Detailed Implementation

[0014] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In the absence of conflict, the following embodiments and their technical features can be combined with each other.

[0015] The first aspect of this application provides a sub-pixel driving unit, with reference to... Figure 2As shown, the sub-pixel driving unit includes a sub-pixel driver 110 and a sensing circuit 120; The sensing circuit 120 is used to perform timing control on the sensing signal, generate digital data corresponding to the sensing signal, and send the digital data to the sub-pixel driver 110. The sub-pixel driver 110 is used to receive the digital data and drive the sub-pixel to emit light when the corresponding sub-pixel needs to emit light based on the digital data.

[0016] The aforementioned sensing signals can be generated by the control circuit or controller corresponding to the display panel, so that the sensing signals can be used to control each pixel of the display panel to emit light. Specifically, the sensing signals can be used to characterize the time period during which the corresponding sub-pixel needs to emit light, so that the corresponding digital data can instruct the sub-pixel driver 110 to drive the sub-pixel to emit light when the corresponding sub-pixel needs to emit light.

[0017] The sensing circuit 120 can perform timing control on the sensing signal according to the light emission requirements of the corresponding sub-pixel, generating digital data to indicate the light emission of the corresponding sub-pixel. The aforementioned digital data may include binary data such as 1 and 0, where 1 can be used to represent a high level and 0 can be used to represent a low level. The digital data is input to the sub-pixel driver 110, causing the switching transistors and other devices in the sub-pixel driver 110 to be turned on or off, thereby driving the corresponding sub-pixel to emit light.

[0018] Optionally, the sub-pixel driver 110 described above may include Figure 1b The driver shown may also include other display driver chips that can be controlled by the digital data output by the sensing circuit 120. Optionally, the sub-pixel driver 110 may include a simple ADC (analog-to-digital converter) module structure using a source data driver, which can be converted into a simple ADC block based on time without increasing the circuit area of ​​the sub-pixel driving unit by utilizing an existing DAC source data driver.

[0019] The aforementioned sub-pixel driving unit uses the sensing circuit 120 to perform timing control on the sensing signal and generate digital data corresponding to the sensing signal. This digital data can control the sub-pixel driver 110 in real time, so that the sub-pixel driver 110 can drive the corresponding sub-pixel to emit light based on the digital data. Specifically, it can compensate in real time when the corresponding sub-pixel needs to be displayed (Displayon), so that the sub-pixel driver 110 drives the corresponding sub-pixel to emit light. The driving process does not require additional storage or sensing data compression modules, so that the corresponding display panel does not need to set up storage modules and sensing data compression modules, etc. It can also simplify the relevant interface settings, thereby reducing the area of ​​the corresponding driving chip or display panel, thereby reducing the design workload and reducing the corresponding process cost.

[0020] In one embodiment, the digital data includes first digital data and second digital data. The first and second digital data can be the same digital data generated by the sensing circuit 120 through timing control of the sensing signal, for example... Figure 3 The digital data shown is Emission; the first digital data and the second digital data can be two digital data generated by the sensing circuit 120 through timing control of the sensing signal, that is, the first digital data is one digital data output by the sensing circuit 120, and the second digital data is another digital data output by the sensing circuit 120. These two digital data can be the same or not completely the same.

[0021] Specifically, refer to Figure 3 As shown, the sub-pixel driver 110 includes a first capacitor C1, a second capacitor C2, 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, an eighth transistor M8, and a ninth transistor M9.

[0022] The control terminal of the first transistor M1 is used to receive the n-1 level scan signal Scan(n-1), the input terminal is used to receive the initial voltage Initial, and the output terminal is connected to the first electrode of the first capacitor C1 and the control terminal of the fourth transistor M4. The first electrode of the first capacitor C1 is connected to the input terminal of the fourth transistor M4, and the second electrode is connected to the input terminal of the fifth transistor M5. The input terminal of the fifth transistor M5 is used to connect to the first power supply ELVDD. The control terminal of the second transistor M2 is used to receive the n-level scan signal Scan(n), and the input terminal is used to receive the data signal Data and is connected to the input terminal of the ninth transistor M9. The control terminal of the third transistor M3 is used to receive the n-level scan signal Scan(n), the input terminal is connected to the output terminal of the fourth transistor M4, and the output terminal is connected to the control terminal of the fourth transistor M4. The control terminal of the seventh transistor M7 is used to receive the n-level scan signal Scan(n), the input terminal is connected to the first electrode of the second capacitor C2, and the output terminal is connected to the input terminal of the fourth transistor M4. The control terminal of the eighth transistor M8 is used to receive the n-level scan signal Scan(n), the input terminal is connected to the second electrode of the second capacitor C2, and the output terminal is connected to the control terminal of the fourth transistor M4. The control terminal of the ninth transistor M9 is used to receive the second digital data Emission, and the output terminal is connected to the second electrode of the second capacitor C2. The input terminal of the fourth transistor M4 is connected to the output terminal of the fifth transistor M5, and the output terminal is connected to the input terminal of the sixth transistor M6; the control terminals of the sixth transistor M6 and the fifth transistor M5 are respectively used to receive the first digital data Emission; the output terminal of the sixth transistor M6 outputs the second power supply ELVSS to the corresponding sub-pixel, so that the corresponding sub-pixel emits light under the control of the first power supply ELVDD and the second power supply ELVSS to realize the corresponding display function.

[0023] When the sub-pixel driver 110 provided in this embodiment performs the driving function, its on-current IOLED is independent of the relevant threshold voltage, which can improve or even eliminate the influence of the threshold voltage drift of the driving transistor on the on-current IOLED, and is beneficial to improving the uniformity of display brightness.

[0024] Optionally, the first electrode of the first capacitor C1 can be its negative electrode, and the second electrode can be its positive electrode. Optionally, the first electrode of the second capacitor C2 can be its positive electrode, and the second electrode can be either a positive or negative electrode.

[0025] Optionally, the fourth transistor M4 is an N-channel MOS transistor, which can be used as the driving transistor of the sub-pixel driver 110; the other transistors in the sub-pixel driver 110 can be P-channel MOS transistors.

[0026] Specifically, when the sub-pixel driver 110 performs the driving function, the first transistor M1, the second transistor M2, the third transistor M3, the seventh transistor M7, and the eighth transistor M8 are all turned off when the fourth transistor M4 and the fifth transistor M5 are turned on, and are all turned on when the fourth transistor M4 and the fifth transistor M5 are turned off.

[0027] The sub-pixel driving unit described above uses the sensing circuit 120 to perform timing control on the sensing signal, generating digital data corresponding to the sensing signal. This digital data can control the sub-pixel driver 110 in real time, so that the sub-pixel driver 110 drives the corresponding sub-pixel to emit light based on the digital data. Specifically, it can compensate in real time when the corresponding sub-pixel needs to emit light to turn on the display, causing the sub-pixel driver 110 to drive the corresponding sub-pixel to emit light. The entire driving process does not require additional storage or sensing data compression modules, eliminating the need for storage modules and sensing data compression modules in the corresponding display panel. It also simplifies related interface settings, achieving the goal of reducing the area of ​​the corresponding driving chip or display panel, thereby reducing design workload and lowering corresponding process costs. In addition, when the sub-pixel driver 110 performs the driving function, its conduction current IOLED is independent of the relevant threshold voltage, which can improve or even eliminate the impact of the threshold voltage drift of the driving transistor on the conduction current IOLED, which is beneficial to improving the uniformity of display brightness. It can be seen that the above-mentioned sub-pixel driving unit can improve the uniformity of display brightness of the corresponding display panel while reducing the corresponding circuit area.

[0028] A second aspect of this application provides a pixel circuit including at least one sub-pixel driving unit as described in any of the above embodiments, so as to reduce the circuit area of ​​the pixel circuit, thereby reducing the design workload and lowering the corresponding process cost.

[0029] In one embodiment, the pixel circuit further includes a plurality of sub-pixel light-emitting units; the sub-pixel driving unit is used to drive at least one of the sub-pixel light-emitting units to emit light.

[0030] Specifically, there is a correspondence between sub-pixel driving units and sub-pixel emissive units. One sub-pixel driving unit can correspond to multiple sub-pixel emissive units, for example, as shown in the reference... Figure 4a As shown, a single sub-pixel driving unit simultaneously drives multiple corresponding sub-pixel light-emitting units for illumination display. Sub-pixel driving units and sub-pixel light-emitting units can also correspond one-to-one, for example, as shown in the reference... Figure 4b As shown, the corresponding sub-pixel light-emitting unit is driven to emit light through the sub-pixel driving unit.

[0031] A pixel circuit may include multiple pixel units, and a pixel unit may include multiple sub-pixel light-emitting units. Each sub-pixel light-emitting unit corresponds to a different color channel. Specifically, refer to... Figure 5 As shown, a pixel unit includes three sub-pixel light-emitting units: an R-channel light-emitting unit, a G-channel light-emitting unit, and a B-channel light-emitting unit. These three sub-pixel light-emitting units can correspond to the same sub-pixel driving unit or different sub-pixel driving units. Figure 5 The pixel unit shown only outputs the sub-pixel driving unit corresponding to the R channel light-emitting unit.

[0032] The above pixel circuit includes at least one sub-pixel driving unit as described in any of the above embodiments, and has all the beneficial effects of the sub-pixel driving unit as described in any of the above embodiments, which will not be repeated here.

[0033] A third aspect of this application provides a display panel that includes the pixel circuit described in any of the above embodiments.

[0034] The above display panel includes at least one pixel circuit as described in any of the above embodiments, and has all the beneficial effects of the pixel circuit as described in any of the above embodiments, which will not be repeated here.

[0035] Although this application has been shown and described with respect to one or more implementations, equivalent variations and modifications will occur to those skilled in the art based on a reading and understanding of this specification and the accompanying drawings. This application includes all such modifications and variations and is limited only by the scope of the appended claims. In particular, with respect to the various functions performed by the aforementioned components, the terminology used to describe such components is intended to correspond to any component (unless otherwise indicated) that performs the specified function of said component (e.g., is functionally equivalent to it), even if structurally not equivalent to the disclosed structure performing the functions in the exemplary implementations of this specification shown herein.

[0036] That is, the above description is only an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, such as the combination of technical features between different embodiments, or direct or indirect application in other related technical fields, are similarly included within the patent protection scope of this application.

[0037] Furthermore, it should be understood that in the description of this application, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, 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. Additionally, for structural elements with the same or similar characteristics, this application may use the same or different reference numerals for identification. Moreover, 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, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0038] In this application, the term "exemplary" is used to mean "serving as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as more preferred or advantageous than other embodiments. This application has been provided above to enable any person skilled in the art to implement and use it. Various details have been set forth in the above description for purposes of explanation. It should be understood that those skilled in the art will recognize that this application can be implemented without using these specific details. In other embodiments, well-known structures and processes will not be described in detail to avoid obscuring the description of this application with unnecessary detail. Therefore, this application is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed herein.

Claims

1. A sub-pixel driving unit, characterized in that, Includes sub-pixel drivers and sensing circuits; The sensing circuit is used to perform timing control on the sensing signal, generate digital data corresponding to the sensing signal, and send the digital data to the sub-pixel driver. The sub-pixel driver is used to receive the digital data and drive the sub-pixel to emit light when the corresponding sub-pixel needs to emit light based on the digital data; The digital data includes first digital data and second digital data; the sub-pixel driver includes a first capacitor, a second capacitor, a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, and a ninth transistor; the control terminal of the first transistor is used to receive an n-1 level scan signal, the input terminal is used to receive an initial voltage, and the output terminal is connected to the first electrode of the first capacitor and the control terminal of the fourth transistor; the first electrode of the first capacitor is connected to the input terminal of the fourth transistor, the second electrode is connected to the input terminal of the fifth transistor, and the input terminal of the fifth transistor is used to connect to a first power supply; the control terminal of the second transistor is used to receive an n-level scan signal, the input terminal is used to receive a data signal and is connected to the input terminal of the ninth transistor; the control terminal of the third transistor is used to receive an n-level scan signal, and the input terminal is connected to the fourth transistor. The output terminal of the body transistor is connected to the control terminal of the fourth transistor; the control terminal of the seventh transistor is used to receive n-level scan signals, its input terminal is connected to the first electrode of the second capacitor, and its output terminal is connected to the input terminal of the fourth transistor; the control terminal of the eighth transistor is used to receive n-level scan signals, its input terminal is connected to the second electrode of the second capacitor, and its output terminal is connected to the control terminal of the fourth transistor; the control terminal of the ninth transistor is used to receive second digital data, and its output terminal is connected to the second electrode of the second capacitor; the input terminal of the fourth transistor is connected to the output terminal of the fifth transistor, and its output terminal is connected to the input terminal of the sixth transistor; the control terminals of the sixth transistor and the fifth transistor are respectively used to receive first digital data; the output terminal of the sixth transistor outputs a second power supply to the corresponding sub-pixel, so that the corresponding sub-pixel emits light under the control of the first power supply and the second power supply.

2. The sub-pixel driving unit according to claim 1, characterized in that, The fourth transistor is an N-channel MOS transistor, and the other transistors in the sub-pixel driver are P-channel MOS transistors.

3. The sub-pixel driving unit according to claim 1, characterized in that, The first transistor, the second transistor, the third transistor, the seventh transistor, and the eighth transistor are all off when the fourth transistor and the fifth transistor are on, and all are on when the fourth transistor and the fifth transistor are off.

4. A pixel circuit, characterized in that, It includes at least one sub-pixel driving unit as described in any one of claims 1 to 3.

5. The pixel circuit according to claim 4, characterized in that, The pixel circuit further includes a sub-pixel light-emitting unit; the sub-pixel driving unit is used to drive at least one of the sub-pixel light-emitting units to emit light.

6. A display panel, characterized in that, Includes the pixel circuit as described in claim 4 or 5.

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