Display device

Abstract

The invention relates to a display device. The display device comprises a plurality of pixels and a plurality of groups of driving chips which are arranged in an array; each pixel comprises a sub-pixels with different colors, each group of driving chips comprises a driving chips, and output channels of the driving chips are connected with the sub-pixels in a one-to-one correspondence manner; wherein the a sub-pixels of each pixel are respectively connected with a driving chips in one group of driving chips in a one-to-one correspondence manner, and each driving chip is connected with the sub-pixels of a colors; a is a positive integer greater than 1. The total driving currents of different driving chips are similar, so that the problem of color cast caused by large difference of the total driving currents of the different driving chips can be solved. And the number of output channels of the driving chip is not limited by the multiple of pixel colors.

Description

Technical Field

[0001] This application relates to display devices, and more particularly to a display apparatus. Background Technology

[0002] Figure 1 This is an exemplary LED (light-emitting diode) display array structure, which is a common-anode structure, meaning that in the same row, the anodes of the three LED beads (RGB, red, green, and blue) are connected together, while the cathodes are separate. Figure 1 To avoid omission, only one color of LED beads is shown. Figure 1 The wavy dashed lines in the diagram indicate the omission of rows and columns in the array. A common cathode structure is... Figure 1 All LED beads are connected in reverse. Figure 1 Row drives typically use PMOS transistors (P-channel metal-oxide-semiconductor field-effect transistors), while column drives typically use constant current source driver chips. For example, each constant current source driver chip contains multiple constant current output drive channels (OUT), which are terminated... Figure 1 The column lines in the array (column 1 / column 2... / column n).

[0003] Figure 1 The working principle of the structure shown is as follows:

[0004] 1. First, display row 1. The PMOS in row 1 is turned on, while the PMOS in other rows is turned off. The row lines in row 1 are connected to the power supply, while the row lines in other rows are high impedance.

[0005] 2. Column drive (constant current source drive): Output constant current sources according to the corresponding columns of the display data in row 1, light up the LED display beads in row 1, and display the display image in row 1.

[0006] 3. Repeat steps 1-2, line breaks, until all lines are displayed.

[0007] One exemplary solution is to connect all output channels of a constant current source driver chip to LEDs of the same color. However, to configure the white balance of the display, the driving currents of red, green, and blue LEDs are usually different, with red having the highest current. This results in the total current flowing through the constant current source driver chip connected to the red LED being greater than that of the other two colors. Over time, this leads to locally higher temperatures near the chip, resulting in color distortion.

[0008] If you want to drive RGB LEDs with a single constant current source driver chip, an exemplary approach is to connect three adjacent output channels of the same constant current source driver chip to the same pixel, i.e., the same group of RGB LEDs. However, when the number of chip output channels is not a multiple of 3, there will be channels left over. Summary of the Invention

[0009] Therefore, it is necessary to provide a solution that can resolve the color distortion problem and ensure that there are no excess output channels when the number of output channels of the driver chip is not a multiple of a.

[0010] A display device includes a plurality of pixels arranged in an array and a plurality of driving chips; each pixel includes a sub-pixels of different colors, each group of driving chips includes a driving chips, and the output channel of each driving chip is connected to the sub-pixels in a one-to-one correspondence; wherein, the a sub-pixels of each pixel are respectively connected to the a driving chips in a group of driving chips in a one-to-one correspondence, and each driving chip is connected to the sub-pixels of a different color; a is a positive integer greater than 1.

[0011] In the aforementioned display device, each driver chip connects to sub-pixels of all colors. Therefore, the driving current output by each driver chip is a mixture of the driving currents of various color sub-pixels. The total driving current of different driver chips is similar, thus solving the color shift problem caused by large differences in the total driving current of different driver chips. Furthermore, the output channels are allocated such that each group of driver chips includes *a* driver chips, and each pixel's *a* sub-pixels are connected one-to-one with *a* driver chips. The number of pixels connected to a driver chip is equal to the number of output channels, therefore the number of output channels of a driver chip is not limited by the multiples of pixel colors.

[0012] In one embodiment, the same output channel of each driver chip in each group of driver chips is connected to a sub-pixels of different colors of the same pixel.

[0013] In one embodiment, adjacent output channels of the same driver chip are connected to sub-pixels of different colors.

[0014] In one embodiment, a=3, and each pixel includes three sub-pixels of R, G, and B colors.

[0015] In one embodiment, three adjacent output channels of each driver chip are connected to sub-pixels of different colors.

[0016] In one embodiment, each driver chip has b output channels for outputting drive current.

[0017] In one embodiment, the color order of the sub-pixels connected to the first to b output channels of the driver chip includes: a first order in RGB cycle, a second order in GBR cycle, and a third order in BRG cycle; the three driver chips in each group of driver chips are respectively connected to the sub-pixels in the first order, the second order, and the third order.

[0018] In one embodiment, the color order of the sub-pixels connected to the first to b output channels of the driver chip includes: a first order of RBG cycle, a second order of BGR cycle, and a third order of GRB cycle; the three driver chips in each group of driver chips are connected to the sub-pixels in the first, second, and third orders, respectively.

[0019] In one embodiment, each driver chip includes:

[0020] There are a current output modules, each including at least one current generating unit, and the a current output modules together include b current generating units. Each current generating unit is connected to one of the output channels. The current generating units in the same current output module are used to output the driving current of sub-pixels of the same color. There are a PWM modules, each including at least one PWM generating unit. The PWM generating units correspond one-to-one with the current generating units and are used to control the duration of the current output by each current generating unit. A color selection module is used to control each current generating unit to generate the driving current of the corresponding color according to the color order of the sub-pixels connected to the first to b output channels of the driver chip.

[0021] In one embodiment, the color selection module includes: a sequence selection register for storing the color order of the sub-pixels connected to the first to b output channels of the driver chip; registers for a different color sub-pixels; and a sequence selection unit connected between the registers of the a different color sub-pixels and the a PWM modules, for allocating the registers of each color sub-pixel to the corresponding PWM modules according to the color order data stored in the sequence selection register.

[0022] In one embodiment, the color selection module includes: a sequence selection register for storing the color order of sub-pixels connected to the first to b output channels of the driver chip; a registers for a different color sub-pixels; and a sequence selection unit connected to the registers for the a different color sub-pixels for configuring the color corresponding to each register according to the color order data stored in the sequence selection register.

[0023] In one embodiment, the color selection module includes: a sequence selection register for storing the color order of the sub-pixels connected to the first to b output channels of the driver chip; a registers for a different color sub-pixels; and a sequence selection unit connected to the a PWM modules and the a current output modules for selecting which current output module to output the PWM signal generated by each PWM module.

[0024] In one embodiment, the display device is an LED display screen.

[0025] In one embodiment, each of the driver chips is a column driver chip. Attached Figure Description

[0026] To better describe and illustrate embodiments and / or examples of the inventions disclosed herein, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed inventions, the currently described embodiments and / or examples, or the best mode of these inventions as currently understood.

[0027] Figure 1 This is an exemplary LED display array structure.

[0028] Figure 2 This is a schematic diagram of the driver chip connecting sub-pixels in one embodiment of this application.

[0029] Figure 3 This is a schematic diagram of the structure of a driver chip in one embodiment of this application.

[0030] Figure 4 This is a circuit diagram of the color selection module 110 in one embodiment of this application.

[0031] Figure 5 This is a circuit diagram of the color selection module 110 in another embodiment of this application.

[0032] Figure 6 This is a circuit diagram of the color selection module 110 in another embodiment of this application. Detailed Implementation

[0033] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this invention, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0036] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0037] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0038] This application proposes a system-level architecture and implementation method for a driver chip. For a display device where each pixel includes a sub-pixels of different colors, the output channels with the same number of each of the a driver chips are connected to the same pixel. Regardless of the number of channels, this solves the problem of leftover output channels, and the internal design of the driver chip is simple.

[0039] Based on the aforementioned inventive concept, this application proposes a display device, including multiple pixels arranged in an array and multiple sets of driving chips; each pixel includes a sub-pixels of different colors, each set of driving chips includes a driving chips, and the output channel of each driving chip is connected to the sub-pixels in a one-to-one correspondence; wherein, the a sub-pixels of each pixel are respectively connected to the a driving chips in a set of driving chips in a one-to-one correspondence, and each driving chip is connected to a sub-pixels of a different color; a is a positive integer greater than 1.

[0040] In the aforementioned display device, each driver chip connects to sub-pixels of all colors. Therefore, the driving current output by each driver chip is a mixture of the driving currents of various color sub-pixels. The total driving current of different driver chips is similar, thus solving the color shift problem caused by large differences in the total driving current of different driver chips. Furthermore, the output channels are allocated such that each group of driver chips includes *a* driver chips, and each pixel's *a* sub-pixels are connected one-to-one with a channel of one of the *a* driver chips. The number of pixels connected is equal to the number of output channels of the driver chip; therefore, the number of output channels of the driver chip is not limited by the multiples of the pixel colors.

[0041] In one embodiment of this application, the display device is an LED display screen.

[0042] In one embodiment of this application, the same output channel of each driver chip in each group of driver chips is respectively connected to a sub-pixels of different colors of the same pixel.

[0043] For example, the same output channel can refer to the same output channel number. For instance, in a display device where each pixel includes three sub-pixels: R (red), G (green), and B (blue), in each group of driver chips, the output channel (OUT0) of the first driver chip numbered 0 is connected to the R sub-pixel, the output channel of the second driver chip numbered 0 is connected to the G sub-pixel, and the output channel of the third driver chip numbered 0 is connected to the B sub-pixel.

[0044] For example, the same output channel can refer to the same output channel located in different driver chips. For example, Figure 2 In the diagram, the first output channel in the upper left corner of each driver chip refers to the output channel at the same location.

[0045] In one embodiment of this application, adjacent channels of the same driver chip are connected to sub-pixels of different colors. For example, if the output channel OUT0 of a driver chip is connected to an R sub-pixel, then its output channel OUT1 is not connected to an R sub-pixel; for example, it could be connected to a G sub-pixel.

[0046] In one embodiment of this application, the output channels OUT0, OUT1, ... of each driver chip are arranged in a counter-clockwise order. In other embodiments, the output channels may be arranged in other orders, such as clockwise.

[0047] In one embodiment of this application, each driver chip includes b output channels for outputting driving current supplied to sub-pixels, and the color order of the sub-pixels connected to the first to b output channels includes a possible sequences. For example, when a=3, it can include a first sequence according to the RGB cycle, a second sequence according to the GBR cycle, and a third sequence according to the BRG cycle; the three driver chips in each group of driver chips are connected to the sub-pixels according to the first, second, and third sequences, respectively. In some embodiments of this application, the first, second, and third sequences are respectively: a first sequence according to the RGB cycle, a second sequence according to the BGR cycle, and a third sequence according to the GRB cycle.

[0048] It should be noted that here, the first to b output channels can refer to channels in order of channel number, such as out. 0、 out1、……、out b-1 It can also refer to channels arranged in a counterclockwise or clockwise order, or a combination of counterclockwise and clockwise order, or a combination of clockwise and counterclockwise order, starting from channel i at a certain position.

[0049] With channel i as Figure 2 Taking out0 as an example, following the counter-clockwise order, for example, Figure 2 In the middle, out0, out1, ..., out7, out8, out9, ..., out b-1 ;

[0050] Alternatively, it can be done in a clockwise order, starting with channel i. Figure 2 Taking out15 as an example, for instance, out 15 out 14 ,...out8,out7,out6,...,out0;

[0051] It can also be counterclockwise first, then clockwise, with channel i as... Figure 2 Taking out0 as an example, for instance, out0, out1, ..., out7, out 15 out 14 ...out8;

[0052] It can also be clockwise first, then counterclockwise, with channel i as... Figure 2 Taking out15 as an example, for instance, out 15 out 14,...out8, out0, out1,...out7.

[0053] In one embodiment of this application, the driving chip is a constant current driving chip.

[0054] Figure 2 This is a schematic diagram of the driver chip connecting sub-pixels in one embodiment of this application. Figure 2 The ellipsis in the text indicates that several columns of the pixel array have been omitted, and the double wavy line indicates that several rows of the pixel array have been omitted. In this embodiment, each driving chip is a column driving chip, and each pixel (in...) Figure 2 The image (defined by a dashed box) includes three sub-pixels of colors R, G, and B (corresponding to a=3). The three adjacent output channels of each driver chip connect to sub-pixels of different colors.

[0055] exist Figure 2 In the illustrated embodiment, each driver chip includes 16 output channels (output channels OUT0 to OUT15); in other embodiments, each driver chip may have more or fewer output channels. In the first driver chip of each group of driver chips, output channels OUT0 to OUT15 are connected to sub-pixels in the color order RGBRGBRGBR…; in the second driver chip, output channels OUT0 to OUT15 are connected to sub-pixels in the color order GBRGBRGBRG…; and in the third driver chip, output channels OUT0 to OUT15 are connected to sub-pixels in the color order BRGBRGBRGB…. That is, the output channels OUT0 of the three driver chips in a group are connected to the same pixel: the first driver chip's output channel OUT0 is connected to the red sub-pixel, the second driver chip's output channel OUT0 is connected to the green sub-pixel, and the third driver chip's output channel OUT0 is connected to the blue sub-pixel. Similarly, the output channels OUT1 of the three driver chips are connected to the same pixel: the first driver chip's output channel OUT1 is connected to the green sub-pixel, the second driver chip's output channel OUT1 is connected to the blue sub-pixel, and the third driver chip's output channel OUT1 is connected to the red sub-pixel. And so on. The three driver chips connect 16 pixels in each row of the pixel array. In some embodiments of this application, the output channels OUT0 to OUT15 of the first driver chip may be connected to the sub-pixels in the color order RBGR...; the output channels OUT0 to OUT15 of the second driver chip may be connected to the sub-pixels in the color order BGRB...; and the output channels OUT0 to OUT15 of the third driver chip may be connected to the sub-pixels in the color order GRBG...

[0056] In one embodiment of this application, each driver chip internally includes a sequence selection register and a group of current generation units (a). The color registers required by the group of current generation units (a) are switched based on the value of the sequence selection register, while the connection relationship between the current generation units and each output channel remains unchanged, simplifying the design. Since there are only a possible color order (a) for connecting sub-pixels to the output channels, the storage space of the sequence selection register internally in the driver chip can be very small (e.g., when a=3, the sequence selection register can be a 2-bit register), thereby saving costs.

[0057] Figure 3 This is a schematic diagram of the structure of a driver chip in one embodiment of this application. In this embodiment, the driver chip includes: a color selection module 110, b output channels (OUT0 to OUTb), and a current output module ( Figure 3 In the illustrated embodiment, a=3). Each current output module is connected to at least one output channel, and each output channel is connected to only one current output module. One current output module is used to output the driving current of a sub-pixels of one color. a current output modules are configured to output the driving current of a sub-pixels of a colors. A color selection module 110 is connected to each current output module. The color selection module 110 is used to control the color corresponding to the driving current generated by each current output module according to the color order of the sub-pixels connected to the aforementioned output channels. In other words, the color selection module 110 controls each current generating unit to generate the driving current of the corresponding color according to the color order of the sub-pixels connected to the first to b output channels of the driver chip.

[0058] For example, suppose the output channel of a certain driver chip is connected to sub-pixel colors in the order RGBRGB... then Figure 3 In this process, the color selection module 110 controls the current output module 1 to output the current used to drive the red pixel, the current output module 2 to output the current used to drive the green pixel, and the current output module 3 to output the current used to drive the blue pixel, according to the sequence.

[0059] In one embodiment of this application, each current output module includes at least one current generating unit, and a current output modules include a total of b current generating units. Each current generating unit is connected to an output channel. The current generating units within the same current output module are configured to output driving current for sub-pixels of the same color. The driver chip also includes a PWM modules, each including at least one PWM generating unit. The PWM generating units correspond one-to-one with the current generating units and are used to control the duration of the current output by the current generating units. Further, the PWM generating units generate PWM signals of corresponding widths according to the size of the image data to be displayed. In one embodiment of this application, the red PWM module, green PWM module, and blue PWM module generate PWM signals corresponding to their respective colors, as well as related control signals such as shadow removal and decoupling.

[0060] In one embodiment of this application, the color selection module 110 includes:

[0061] The sequence selection register stores the color order of the sub-pixels connected to the output channels of the driver chip in which it resides. In other words, it stores the color order of the sub-pixels connected to the first to bth output channels of the driver chip.

[0062] A register for a different color sub-pixel, such as a red register, a green register, and a blue register.

[0063] The sequence selection unit 112 is used to select which color of sub-pixel's driving current each current output module outputs. For example, Figure 3 The current output module 1, current output module 2, and current output module 3 each output the driving current for which color sub-pixel.

[0064] Figure 4 This is a circuit diagram of the color selection module 110 in one embodiment of this application. In this embodiment, the sequence selection unit 112 is connected between the registers of a different color sub-pixels and a PWM modules, and is used to allocate the registers of each color sub-pixel to the corresponding PWM modules according to the color sequence data stored in the sequence selection registers. That is, the color allocated by a certain PWM module can be red, or green or blue depending on the color sequence data stored in the sequence selection register.

[0065] Figure 5This is a circuit diagram of the color selection module 110 in another embodiment of this application. In this embodiment, the sequential selection unit 112 is connected to registers of a different color sub-pixels, and is used to configure the color corresponding to each register according to the color sequence data stored in the sequential selection register. That is, the sequential selection register can control the color signal transmitted to each register. If the color signal transmitted to a register is a red signal, then that register is configured as a red register. Each register configured with a color is connected to a PWM module, and the control signal of the corresponding color is transmitted to the PWM module.

[0066] Figure 6 This is a circuit diagram of the color selection module 110 in another embodiment of this application. In this embodiment, the sequence selection unit 112 connects a PWM modules and a current output modules, and is used to select which current output module to output the PWM signal generated by each PWM module.

[0067] For example, Figure 6 In the process, based on the color sequence data stored in the sequence selection register, the PWM signal of the red PWM module is output to the current output module 1, the PWM signal of the green PWM module is output to the current output module 2, and the PWM signal of the blue PWM module is output to the current output module 3.

[0068] In the description of this specification, references to terms such as "some embodiments," "other embodiments," and "ideal embodiments" 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 the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A display device, characterized in that, It includes multiple pixels arranged in an array and multiple sets of driving chips; each pixel includes a sub-pixels of different colors, each set of driving chips includes a driving chips, and the output channel of each driving chip is connected to the sub-pixels in a one-to-one correspondence; wherein, the a sub-pixels of each pixel are respectively connected to the a driving chips in a set of driving chips in a one-to-one correspondence, and each driving chip is connected to a sub-pixels of a different color; a is a positive integer greater than 1.

2. The display device according to claim 1, characterized in that, In each group of driver chips, the same output channel of each driver chip is connected to a sub-pixels of different colors of the same pixel.

3. The display device according to claim 2, characterized in that, Adjacent output channels of the same driver chip connect sub-pixels of different colors.

4. The display device according to claim 3, characterized in that, a=3, each pixel includes three sub-pixels of R, G and B colors.

5. The display device according to claim 4, characterized in that, Each driver chip has three adjacent output channels connected to sub-pixels of different colors.

6. The display device according to claim 5, characterized in that, Each driver chip has b output channels for outputting drive current, and the color order of the sub-pixels connected to the first to b output channels of the driver chip includes: a first order in RGB cycle, a second order in GBR cycle, and a third order in BRG cycle; The three driver chips in each group are connected to the sub-pixels in the first, second, and third order, respectively.

7. The display device according to claim 5, characterized in that, Each driver chip has b output channels for outputting drive current, and the color order of the sub-pixels connected to the first to b output channels of the driver chip includes: The three driver chips in each group of driver chips are connected to the sub-pixels in the first, second, and third orders, respectively, according to the first, second, and third orders of the RBG cycle.

8. The display device according to claim 6 or 7, characterized in that, Each driver chip includes: There are a current output modules, each current output module including at least one current generating unit, the a current output modules include a total of b current generating units, each current generating unit is connected to one of the output channels; the current generating units in the same current output module are used to output the driving current of sub-pixels of the same color; There are a PWM module, each PWM module includes at least one PWM generation unit; the PWM generation unit corresponds one-to-one with the current generation unit, and is used to control the duration of the current output by each current generation unit; The color selection module is used to control each current generation unit to generate a driving current corresponding to the color according to the color order of the sub-pixels connected to the first to b output channels of the driver chip.

9. The display device according to claim 8, characterized in that, The color selection module includes: A sequence selection register is used to store the color order of the sub-pixels connected to the first to b output channels of the driver chip; Registers for a different color sub-pixels; A sequence selection unit is connected between the registers of the a different color sub-pixels and the a PWM modules, and is used to allocate the registers of each color sub-pixel to the corresponding PWM modules according to the color sequence data stored in the sequence selection registers; or, The sequence selection unit is connected to the registers of the a different color sub-pixels and is used to configure the color corresponding to each register according to the color sequence data stored in the sequence selection register; or, The sequence selection unit connects the a PWM modules and the a current output modules, and is used to select which current output module to output the PWM signal generated by each PWM module.

10. The display device according to claim 9, characterized in that, The display device is an LED display screen.

Images