Display driving method, display driving chip, and display device

Abstract

The present invention discloses a display driving method, a display driving chip, and a display device. The display driving method includes the step of determining whether or not an abnormal signal feedback has been detected, and if detected, switching to a common voltage controlled display mode until the abnormal signal disappears. In the common voltage controlled display mode, the display gray level of the pixel circuit is controlled by the common voltage to realize the display of a warning image. Compared to a display method controlled by a source driving circuit, the complexity of the control process can be significantly reduced, and the number of required memory units can also be reduced.

Description

Technical Field

[0001] This application claims the priority of a Chinese invention application with an application date of June 2, 2023, an application number of 202310647032X, and a title of "Display Driving Method, Display Driving Chip, and Display Device", and incorporates them into this application by reference to the entire specification, claims, drawings, and abstract of the above Chinese invention application.

[0002] [Technical Field] The present invention relates to the field of display technology, and particularly to a display driving method, a display driving chip, and a display device.

Background Art

[0003] The use of liquid crystal display (LCD) panels is very common, and they are used in various life applications and also in in-vehicle display systems.

[0004] In an in-vehicle display system, when a vehicle accident occurs, in order for the driver to appropriately respond to various situations and avoid the expansion of the accident, a mechanism to prompt the driver's attention is very important. Usually, when a driving accident occurs, the display module may be damaged, and most functions of the display driving IC may stop operating normally. At this time, a simple and low-power display method is required to be able to generate a warning pattern corresponding to the display screen.

Summary of the Invention

[0005] In view of the above problems, an object of the present invention is to provide a display driving method, a display driving chip, and a display device to realize a simple and low-power display method that can generate a warning pattern corresponding to the display screen.

[0006] According to one aspect of the present invention, a display driving method is provided, which includes the step of determining whether or not an abnormal signal feedback has been detected, and if detected, switching to a common voltage controlled display mode until the abnormal signal disappears, wherein in the common voltage controlled display mode, the display gray level of the pixel circuit is controlled by the common voltage to display a warning image.

[0007] The step of selectively switching to a common voltage control display mode until the abnormal signal disappears includes the steps of adjusting the common voltage of the pixel array according to a display pattern and supplying a fixed source drive voltage to the pixel array.

[0008] The step of selectively adjusting the common voltage of the pixel array according to a display pattern includes dividing the common electrode into multiple partitions and controlling the bias voltage of the common electrode according to different partitions.

[0009] Selectively, the number of display gray levels in the pixel circuit corresponds to a number of predetermined values ​​of the bias voltage of the common electrode, wherein the bias voltage of the common electrode includes at least a first predetermined value corresponding to the display of a bright screen gray level and a second predetermined value corresponding to the display of a dark screen gray level.

[0010] Selectively, the voltage value of the fixed source drive voltage matches the first predetermined value.

[0011] Selectively, the bias voltage of the common electrode further includes a plurality of third predetermined values ​​between the first predetermined value and the second predetermined value.

[0012] Selectively, the voltage values ​​of the fixed source drive voltage include a plurality of fixed values ​​that correspond to the first predetermined value and the plurality of third predetermined values.

[0013] Selectively, the abnormal signal indicates that the memory unit in the display drive circuit is malfunctioning.

[0014] Selectively, if the bias voltage of the common electrode of the pixel corresponding to the warning image is set to the first predetermined value, a bright warning image is generated, and if the bias voltage of the common electrode of the pixel corresponding to the warning image is set to the second predetermined value, a dark warning image is generated.

[0015] According to another aspect of the present invention, a display driver chip is provided for performing the display driving method described in any one of the above paragraphs.

[0016] According to another aspect of the present invention, a display device is provided which includes a pixel array having a plurality of pixel units arranged in rows and columns, wherein the display driver chip described above is used to provide scanning signals to pixel units located in corresponding rows of the pixel array, to supply control voltages to pixel units located along corresponding columns, and to switch to a common voltage controlled display mode when abnormal signal feedback is detected until the abnormal signal disappears.

[0017] The display driving method provided by the present invention is applied to an array-type liquid crystal panel and changes the voltage difference between the common voltage on the liquid crystal panel and the source drive voltage supplied to the pixels by the source drive circuit. As a result, when the source drive circuit outputs a fixed voltage, the liquid crystal panel generates a specific pattern. Compared to display methods controlled by a source drive circuit, the complex control process can be significantly reduced, and the number of required memory units can also be reduced. [Brief explanation of the drawing]

[0018] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

[0019] [Figure 1] A schematic diagram and an equivalent circuit diagram of a liquid crystal display device provided by an embodiment of the present invention are shown. [Figure 2] A schematic diagram and an equivalent circuit diagram of a liquid crystal display device provided by an embodiment of the present invention are shown. [Figure 3]A flowchart of the display driving method for abnormal situations provided by an embodiment of the present invention is shown. [Figure 4] A flowchart shows the specific steps of the display driving method for abnormal situations provided by an embodiment of the present invention. [Figure 5] A schematic diagram of the common electrode partition of a display panel provided by an embodiment of the present invention is shown. [Figure 6] A schematic diagram of the display pattern in the display panel provided by an embodiment of the present invention is shown. [Modes for carrying out the invention]

[0020] Various embodiments of the present invention will be described in more detail below with reference to the drawings. In each drawing, the same element or module is represented by the same or similar reference number. For clarity, the parts of the drawings are not drawn to a fixed scale.

[0021] In the following explanation, “circuit” may include hardware circuits, programmable circuits, state machine circuits, and / or combinations of elements capable of storing instructions executed by programmable circuits. When an element or circuit is described as being “connected” to another element, or when an element or circuit is described as being “connected” between two nodes, it may be directly coupled or connected to the other element, or there may be an intervening element, and the connection between elements may be a physical connection, a logical connection, or a combination thereof. In contrast, when an element is described as being “directly coupled” or “directly connected” to another element, it means that there is no intervening element between the two.

[0022] At the same time, in this specification and the claims, specific words are used to refer to specific components. A person skilled in the art can understand that hardware manufacturers may use different names to refer to the same component. In this specification and the claims, instead of using the difference in names as a method to distinguish components, the difference in the functions of the components is used as the criterion for distinction.

[0023] In addition, in this specification, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and it is not necessarily required or implied that there is such an actual relationship or sequence between these entities or operations. Furthermore, the terms "comprising", "containing", or other variations thereof are intended to cover non-exclusive inclusion. A process, method, article, or device that includes a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such a process, method, article, or device. Without further limitation, an element defined by the description "comprising one..." does not exclude the presence of additional identical elements in the process, method, article, or device that includes the said element.

[0024] FIG. 1 and FIG. 2 respectively show a schematic structural diagram and an equivalent circuit diagram of a liquid crystal display device provided by an embodiment of the present invention.

[0025] As shown in Figures 1 and 2, the liquid crystal display device 100 includes a first glass substrate 110 and a second glass substrate 210 whose first surface faces the first surface of the first glass substrate 110. Multiple gate scan lines 111 and multiple source data lines 112 are arranged at the intersection of the first surface of the first glass substrate 110, and thin-film transistors 113 and pixel electrodes 114 are positioned at these intersections. A common electrode 211 is formed on the first surface of the second glass substrate 210. A liquid crystal layer is included between the pixel electrode 114 and the common electrode 211, which corresponds to a pixel capacitor CLC. By gate-controlling the thin-film transistor 113 via the gate scan lines 111 and applying a voltage corresponding to the gray level to the pixel capacitor CLC via the source data lines 112, the orientation of the liquid crystal molecules is changed to achieve the brightness of the corresponding gray level. To maintain the voltage between pixel update cycles, the pixel capacitor CLC can be connected in parallel with a storage capacitor Cs to maintain it for a longer time.

[0026] The display drive circuit in the display device 100 includes a gate drive device 210 connected to a plurality of gate scan lines 111, which supplies gate voltages Vg1 to Vgm and a fixed gate voltage in the event of an abnormality; a source drive device 220 connected to a plurality of source data lines 112, which supplies source voltages Vs1 to Vsn; and a common voltage management module 230 that provides a predetermined common voltage to each common electrode in the event of an abnormality.

[0027] In the display device of the present invention, the display driver chip is used to provide scanning signals to pixels located in corresponding rows of the pixel array, to supply control voltages to pixels located along corresponding columns, and to switch to a common voltage control display mode when an abnormal signal feedback is detected until the abnormal signal disappears. The common voltage control display mode will be described later.

[0028] The display driver circuit described above may be used independently as a display driver chip, or it may be integrated with touch control into a TDDIC, or Touch and Display Driver Integration chip.

[0029] Figure 3 shows a flowchart of the display driving method for abnormal situations provided by an embodiment of the present invention.

[0030] As shown in Figure 3, when a vehicle accident occurs, most of the functions of the display driver IC may cease to operate normally. In this case, the display driver chip executes the above-described display driving method under abnormal conditions, and this method includes the following steps.

[0031] S1: Determine whether or not an abnormal signal feedback has been detected.

[0032] In step S1, it is determined whether or not an abnormal signal feedback has been detected. If it has been detected, step S2 is executed. If it has not been detected, step S3 is executed. The abnormal situation may be any of the various situations that have been artificially set in advance, such as a failure in the memory unit of the display drive circuit or a failure in the source control circuit.

[0033] S2: Switch to common voltage control display mode until the abnormal signal disappears.

[0034] Figure 4 shows a flowchart of the specific steps of the abnormal display driving method provided by an embodiment of the present invention. In the common voltage controlled display mode, the common voltage controls the display gray level of the pixel circuit to realize the display of a warning image, and the step of switching to the common voltage controlled display mode includes the following steps.

[0035] S21: Adjust the common voltage of the pixel array according to the display pattern.

[0036] Figure 5 shows a schematic diagram of the partition of the common electrode of a display panel provided by an embodiment of the present invention. As shown in Figure 5, the common electrode of the display panel may be divided into two partitions, for example, the left partition and the right partition in the drawing (corresponding to the Left Side and Right Side). Different bias adjustment strategies can be employed for the common electrode of different partitions, such as displaying a bright image and a dark screen opposite it, as will be described later.

[0037] Specifically, taking a common electrode in a 10x10 pixel array as an example, the common electrodes RX1 to RX50 can be divided into one area, and RX51 to RX100 into one partition, allowing for separate display for each partition. When adjusting the bias voltage of the common electrode, the display gray level in one partition may be 2 levels (black / white), 3 levels, or other levels, related to the voltage output accuracy of the common electrode, i.e., corresponding to the number of display gray levels in the pixel circuit and the number of predetermined values ​​for the bias voltage of the common electrode. When the display gray level is 2 levels, the bias voltage of the common electrode in the partition has 2 predetermined values. When the bias voltage of the common electrode is the first predetermined value, the corresponding pixel displays a bright screen when driven. When the bias voltage of the common electrode is the second predetermined value, the corresponding pixel displays a dark screen when driven. In one embodiment, the first predetermined value is, for example, 5V, and the second predetermined value is, for example, 0V.

[0038] Note that the pixel array is merely an example and may be of other sizes. In the above example, if there are 2 display gray levels, and if there are 3 display gray levels, the bias voltage of the common electrode in the partition further includes a third predetermined value, such as 0V, 2.5V, 5V, etc., that is, in addition to the first and second predetermined values ​​mentioned above, it further includes several third predetermined values. The same applies to display gray levels of other numerical values.

[0039] S22: Supplies a fixed source drive voltage to the pixel array.

[0040] In step S22, the source drive circuit supplies a fixed drive voltage, and when the display gray level is level 2, the voltage value of the fixed source drive voltage matches the first predetermined value, and when the display gray level is higher, the voltage value of the fixed source drive voltage includes a plurality of fixed values ​​that match the first predetermined value and the plurality of third predetermined values, respectively.

[0041] S23: Implements control over the display of warning images.

[0042] Figure 6 shows a schematic diagram of a display pattern in a display panel provided by an embodiment of the present invention. In step S23, the display control of a warning image is realized as shown in Figure 6. In one embodiment, the bias voltage of the common electrode of the pixel corresponding to the pattern to be displayed is set to a voltage for displaying a dark screen, i.e., a second predetermined value (the displayed screen corresponds to the left figure), and a dark warning image is generated. In another embodiment, the bias voltage of the common electrode of the pixel corresponding to the pattern to be displayed is set to a voltage for displaying a bright screen, i.e., a first predetermined value (the displayed screen corresponds to the right figure), and a bright warning screen is generated, but the present invention is not limited thereto.

[0043] S3: Displays correctly.

[0044] In step S3, when the above abnormal signal disappears, the display drive circuit displays normally, and the source drive circuit supplies a data voltage corresponding to the display gray level.

[0045] The present invention is applied to an array-type liquid crystal panel and modifies the voltage difference between the source drive voltage supplied to the pixels by the source drive circuit by changing the common voltage on the liquid crystal panel. As a result, when the source drive circuit outputs a fixed voltage, the LCD panel generates a specific pattern. Compared to display methods controlled by a source drive circuit, the complex control process can be significantly reduced, the number of required memory units can be reduced, the display resolution is determined by the number of partitions of the common electrode, and the display gray levels may be 2 levels (black / white), 3 levels, or other levels.

[0046] The present invention is suitable for various fields, particularly automotive or industrial display driver ICs, and when an emergency occurs or a malfunction is detected in the display module, it switches to a simplified display mechanism and generates a pre-set warning pattern to guide the user to take the correct action, so as not to cause confusion or waste valuable emergency response time due to display screen malfunctions.

[0047] It should be noted that those skilled in the art will understand that the terms “during,” “in case,” and “when” used herein in relation to circuit operation are not strictly terms indicating an operation that occurs immediately after the start of an initiation operation, and that there may be small but reasonable delays, such as various transmission delays, between the initiation operation and the reaction initiated by that operation. The terms “approximately” or “substantially” used herein mean that the element has a parameter that is expected to be close to the stated value or position. However, as is well known in the art, there is always a small deviation that makes it difficult for the value or position to exactly match what is stated. It is well established in the art that a deviation of at least 10 percent (10%) (at least 20 percent (20%) in the case of semiconductor doping concentrations) is a reasonable deviation from the exact ideal target described. When used in conjunction with signal states, the actual voltage value or logic state of the signal (e.g., “1” or “0”) will differ depending on whether positive logic or negative logic is used.

[0048] According to the above embodiments of the present invention, these embodiments do not comprehensively describe all details, nor do they limit the invention to these specific embodiments. It is clear from the above description that many modifications and variations are possible. This specification selects and specifically describes these embodiments to better illustrate the principles and practical applications of the present invention. This will enable those skilled in the art to make effective use of the present invention and to modify and utilize it based on the present invention. The scope of protection of the present invention shall be limited to the scope defined by the claims of the present invention and its equivalents.

Claims

1. A step to determine whether or not an abnormal signal feedback has been detected, If detected, the step includes switching to a common voltage control display mode until the abnormal signal disappears, In the aforementioned common voltage controlled display mode, the display gray level of the pixel circuit is controlled by a common voltage, thereby enabling the display of a warning image.

2. The step of switching to the common voltage control display mode until the aforementioned abnormal signal disappears is: A step of adjusting the common voltage of the pixel array according to the display pattern, A display driving method according to claim 1, comprising the step of supplying a fixed source driving voltage to a pixel array.

3. The display driving method according to claim 2, wherein the step of adjusting the common voltage of the pixel array according to the display pattern includes dividing the common electrode into a plurality of partitions and controlling the bias voltage of the common electrode according to the different partitions.

4. The display driving method according to claim 3, wherein the number of display gray levels in the pixel circuit corresponds to the number of predetermined values ​​of the bias voltage of the common electrode, and the bias voltage of the common electrode includes at least a first predetermined value corresponding to the display of a bright screen gray level and a second predetermined value corresponding to the display of a dark screen gray level.

5. The display driving method according to claim 4, wherein the voltage value of the fixed source driving voltage matches the first predetermined value.

6. The display driving method according to claim 4, wherein the bias voltage of the common electrode further includes a plurality of third predetermined values ​​that lie between the first predetermined value and the second predetermined value.

7. The display driving method according to claim 6, wherein the voltage value of the fixed source driving voltage includes a plurality of fixed values ​​that correspond to the first predetermined value and the plurality of third predetermined values.

8. The display driving method according to claim 3, wherein the abnormal signal is a feedback signal received when the memory unit in the display driving circuit fails.

9. The display driving method according to claim 2, wherein a bright warning image is generated when the bias voltage of the common electrode of the pixel corresponding to the warning image is set to a first predetermined value, and a dark warning image is generated when the bias voltage of the common electrode of the pixel corresponding to the warning image is set to a second predetermined value.

10. A display driver chip that performs the display driving method described in any one of claims 1 to 9.

11. Multiple pixel sections arranged in rows and columns, A display device comprising a display driver chip according to claim 10 for providing a scanning signal to pixels located in corresponding rows of a pixel array, supplying a control voltage to pixels located along corresponding columns, and switching to a common voltage controlled display mode when abnormal signal feedback is detected until the abnormal signal disappears.

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