Touch sensing device and method for driving touch sensing device

Abstract

A touch sensing device capable of accurately distinguishing and detecting normal touch and abnormal touch, according to one aspect of the present invention, comprises: a touch raw data generation unit for generating first touch raw data including first sensing values acquired through differential sensing of a plurality of touch sensing channels; a baseline reset determination unit for determining whether to reset an initial baseline by using sensing values of touch sensing channels adjacent to each other in the first touch raw data and reference values of the touch sensing channels adjacent to each other in a predetermined initial baseline; and a baseline reset unit for resetting, when the initial baseline is determined to be reset, the initial baseline by using second touch raw data including second sensing values acquired through differential sensing of the plurality of touch sensing channels.

Description

Touch sensing device and method for driving the touch sensing device

[0001] The present invention relates to a touch sensing device, and more specifically, to a touch sensing device capable of detecting a touch on a display panel.

[0002] As the information society develops, the demand for display devices for displaying images is increasing in various forms, and recently, various types of display devices such as liquid crystal display devices (LCDs) and organic light emitting display devices (OLEDs) are being utilized.

[0003] Recently, display devices equipped with touch screen panels capable of detecting touch inputs such as those from a user's finger or stylus pen have become widely used, moving away from conventional input methods such as buttons, keyboards, and mice. These display devices equipped with touch screen panels include a touch sensing device for accurately detecting the presence or absence of a touch and the touch coordinates (touch location).

[0004] A touch sensing device drives touch electrodes arranged on a touch screen panel to obtain sensing values, and uses these values ​​to generate touch data, such as the presence or absence of a touch or a touch location. Specifically, the touch sensing device can generate touch data based on the difference between touch raw data obtained for each touch sensing channel and a baseline. At this time, the baseline is set when no touch occurs by the user, and the baseline may change depending on the state of the display device. For example, the baseline may change when the display device switches from an on state to an off state, or from an off state to an on state.

[0005] However, if noise is present when the display device's state changes, the baseline may contain noise. For example, if the display device switches from an on to an off state while a user touch is maintained, the user's touch may be included in the baseline. In such cases, the noise in the baseline, which serves as a reference for generating touch data, may cause problems in accurately distinguishing between normal and abnormal touches.

[0006] The present invention is intended to solve the above-described problems, and its technical task is to provide a touch sensing device and a method for driving the touch sensing device that can accurately distinguish and detect normal touch and abnormal touch.

[0007] In addition, another technical object of the present invention is to provide a touch sensing device and a method for driving the touch sensing device that can accurately determine whether a baseline for touch sensing is reset.

[0008] According to an aspect of the present invention for achieving the above-described technical problem, a touch sensing device includes a touch raw data generation unit that generates first touch raw data including first sensing values ​​obtained through differential sensing of a plurality of touch sensing channels; a baseline reset determination unit that determines whether to reset the initial baseline using first sensing values ​​of adjacent touch sensing channels in the first touch raw data and reference values ​​of adjacent touch sensing channels in a predetermined initial baseline; and a baseline reset unit that resets the initial baseline using second touch raw data including second sensing values ​​obtained through differential sensing of the plurality of touch sensing channels when it is determined that the initial baseline is to be reset.

[0009] According to another aspect of the present invention for achieving the above-described technical problem, a method for driving a touch sensing device comprises the steps of: generating an initial baseline using initial touch raw data; generating first touch raw data including first sensing values ​​of a plurality of touch sensing channels; determining whether to reset the initial baseline using a first difference value, which is a difference value between first sensing values ​​of adjacent touch sensing channels in the first touch raw data, and a second difference value, which is a difference value between reference values ​​of adjacent touch sensing channels in the initial baseline; generating second touch raw data including second sensing values ​​of the plurality of touch sensing channels when it is determined to reset the initial baseline; and resetting the initial baseline using the second touch raw data.

[0010] According to the present invention, by preventing noise from being included in the baseline through resetting the baseline, there is an effect of being able to accurately distinguish and detect a normal touch due to the user's intention and an abnormal touch not intended by the user.

[0011] In addition, according to the present invention, since it is possible to determine whether to reset the baseline by using both the difference value between the first sensing values ​​of adjacent touch sensing channels in the first touch raw data and the difference value between the reference values ​​of adjacent touch sensing channels in the initial baseline, there is an effect that normal touch and abnormal touch can be accurately detected even when touching an object such as a touch edge area on a touch screen panel, an area where there is a deviation between adjacent touch sensing channels, and an object where there is a small difference between adjacent touch sensing channels, such as an iron plate.

[0012] In addition, according to the present invention, even if the baseline reset requirement is satisfied, the baseline is reset only when the number of times the baseline reset requirement is satisfied exceeds a predetermined standard number of times, so that the detection accuracy of normal and abnormal touches can be maximized.

[0013] FIG. 1 is a block diagram of a display device including a touch sensing device according to one embodiment of the present invention.

[0014] FIG. 2 is a drawing schematically showing a touch screen panel and a touch sensing device according to the present invention.

[0015] FIG. 3 is a drawing exemplarily showing a differential sensing method of the touch sensing device illustrated in FIG. 2.

[0016] FIG. 4 is a block diagram schematically showing the configuration of a touch controller according to one embodiment of the present invention.

[0017] Fig. 5 is a block diagram schematically showing the configuration of the baseline reset judgment unit illustrated in Fig. 4.

[0018] FIGS. 6A to 6C are diagrams showing examples of cases where a touch sensing device according to one embodiment of the present invention determines to maintain a baseline.

[0019] FIGS. 7A to 7C are diagrams showing examples of cases where a touch sensing device according to one embodiment of the present invention determines to reset a baseline.

[0020] Figure 8 is a flowchart showing a method of driving a touch sensing device according to one embodiment of the present invention.

[0021] The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms. These embodiments are provided solely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined solely by the scope of the claims.

[0022] Throughout the specification, identical reference numbers refer to substantially identical components. In the following description, detailed descriptions of components and functions not related to the core components of the present invention and those known in the art may be omitted.

[0023] In this specification, when the terms "includes," "has," and "consists of," are used, other parts may be added, unless "only" is used. When a component is expressed in the singular, it includes the plural unless otherwise explicitly stated.

[0024] When interpreting a component, it is interpreted as including the error range even if there is no separate explicit description.

[0025] While terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, a "first" component referred to below may also be a "second" component within the technical scope of the present invention.

[0026] The term "at least one" should be understood to include all possible combinations of one or more associated items. For example, "at least one of the first, second, and third items" can mean any combination of items that can be represented by two or more of the first, second, and third items, as well as each of the first, second, and third items.

[0027] The features of each of the various embodiments of the present invention can be partially or wholly combined or combined with each other, and various technical connections and operations are possible, and each embodiment can be implemented independently of each other or implemented together in a related relationship.

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. In the following description, if a detailed description of a known function or configuration related to the present invention is judged to unnecessarily obscure the gist of the present invention, such detailed description will be omitted.

[0029]

[0030] FIG. 1 is a block diagram of a display device including a touch sensing device according to one embodiment of the present invention.

[0031] As illustrated in FIG. 1, a display device (100) including a touch sensing device according to one embodiment of the present invention includes a display panel (111), a touch screen panel (112), a data driving device (120), a gate driving device (130), a timing controller (135), and a touch sensing device (140).

[0032] In the display panel (111), a plurality of data lines (DL) connected to a data driving device (120) may be formed, and a plurality of gate lines (GL) connected to a gate driving device (130) may be formed. For example, the plurality of data lines (DL) may be arranged in rows or columns, and the plurality of gate lines (GL) may be arranged in columns or rows. In the following, for convenience of explanation, it is assumed that the plurality of data lines (DL) are arranged in rows and the plurality of gate lines (GL) are arranged in columns.

[0033] Additionally, a plurality of pixels can be defined at the intersection of a plurality of data lines (DL) and a plurality of gate lines (GL) on the display panel (111).

[0034] The display panel (111) according to the present embodiments may be a self-luminous display in which light-emitting devices (Emitting Devices) provided within the display panel (111) can emit light on their own without a separate light source such as a backlight unit, such as an OLED (Organic Light Emitting Diode) display panel, a Quantum Dot display panel, or a Micro Light Emitting Diode (Micro LED) display panel.

[0035] A plurality of touch electrodes are formed on the touch screen panel (112) to sense touches by a user or a stylus pen, etc. The touch screen panel (112) may be arranged in a different layer, such as above or below the display panel (111), or may be implemented in a form built into the display panel (111). For example, the touch screen panel (112) may be arranged in the display panel (111) in an on-cell type or an in-cell type. The display panel (111) and the touch screen panel (112) may be referred to as a panel (110).

[0036] The data driving device (120) supplies a data signal to the data line (DL) to display image data (DATA) transmitted from the timing controller (135) on each pixel of the display panel (111).

[0037] Such a data driving device (120) may include at least one source drive IC (Integrated Circuit). The at least one source drive IC may include a shift register, a latch circuit, a digital to analog converter (DAC), an output buffer, etc. In some cases, the at least one source drive IC may further include an analog to digital converter (ADC).

[0038] At least one source drive IC may be connected to a bonding pad of the display panel (111) by a tape automated bonding (TAB) method or a chip on glass (COG) method, or may be formed directly on the display panel (111). In some cases, at least one source drive IC may be formed by being integrated into the display panel (111). In addition, at least one source drive IC may be implemented by a chip on film (COF) method.

[0039] The gate driving device (130) sequentially drives a plurality of gate lines (GL) by sequentially supplying scan signals to the plurality of gate lines (GL). The gate driving device (130) may include a shift register, a level shifter, etc.

[0040] The gate driving device (130) may be connected to a bonding pad of the display panel (110) by a tape automated bonding (TAB) method, a chip on glass (COG) method, or a chip on panel (COP: Chip On Panel) method, or may be implemented as a GIP (Gate In Panel) type and directly placed on the display panel (111), and in some cases, may be integrated and placed on the display panel (111). In addition, the gate driving device (130) may be implemented as a chip on film (COF) method in which a plurality of gate driver ICs are implemented and mounted on a gate-circuit film connected to the display panel (111).

[0041] The gate driving device (130) sequentially supplies scan signals of on voltage or off voltage to a plurality of gate lines (GL) under the control of the timing controller (135).

[0042] The timing controller (135) controls the data driving device (120) and the gate driving device (130). The timing controller (135) can control the data driving device (120) and the gate driving device (130) by supplying various control signals (DCS, GCS) necessary for the driving operation of the data driving device (120) and the gate driving device (130).

[0043] The timing controller (135) starts a scan according to the timing implemented in each frame, converts image data input from the outside into a data signal format used by the data drive device (120), outputs the converted image data (DATA), and controls data driving according to the scan.

[0044] The timing controller (135) receives various timing signals including a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input data enable (DE: Data Enable) signal, a clock signal (CLK), etc., along with image data, from an external source (e.g., a host system).

[0045] In addition to converting image data input from the outside into a data signal format used by the data driving device (120) and outputting the converted image data (DATA), the timing controller (135) receives timing signals such as a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input DE signal, and a clock signal to control the data driving device (120) and the gate driving device (130), generates various control signals, and outputs them to the data driving device (120) and the gate driving device (130).

[0046] The timing controller (135) may be implemented as a separate component from the data driving device (120), or may be implemented as an integrated circuit integrated with the data driving device (120).

[0047] The touch sensing device (140) performs a touch sensing function that senses a touch generated by a user or a stylus pen, etc., on the touch screen panel (112).

[0048] Hereinafter, the touch screen panel and touch sensing device according to the present invention will be described in more detail with reference to FIG. 2.

[0049] FIG. 2 is a drawing schematically showing a touch screen panel and a touch sensing device according to the present invention.

[0050] As illustrated in FIG. 2, the touch screen panel (112) includes touch drive lines (TX1 to TXm, where m is a natural number greater than or equal to 2), a plurality of touch electrodes (TE), and touch sensing lines (RX1 to RXn, where n is a natural number greater than or equal to 2). In one embodiment, the touch screen panel (112) may be implemented in a form built into the display device (100). For example, the touch screen panel (112) may be arranged in the display device (100) in an on-cell type.

[0051] Touch driving lines (TX1 to TXm) transmit touch driving signals to each touch electrode (TE), and each touch electrode (TE) includes a mutual capacitor. Touch sensing lines (RX1 to RXn) transmit voltages (or charges) of each touch electrode (TE) to a touch sensing device (140).

[0052] The touch sensing lines (RX1 to RXn) may refer to the sensing lines of the touch screen panel (112) and may also be referred to as touch sensing channels. For convenience of explanation, the terms “touch sensing line” and “touch sensing channel” will be used interchangeably hereinafter.

[0053] In Fig. 2, the touch screen panel (112) is illustrated as a mutual capacitance type touch screen panel including touch drive lines (TX1 to Txm) and touch sensing lines (RX1 to RXn). However, the present invention is not limited thereto, and may be applied to a self-capacitance type touch screen panel in which the supply of a touch drive signal and the reception of electrostatic capacitance generated by a user's touch or a touch of a stylus pen are implemented through the touch sensing lines (RX1 to RXn).

[0054] The touch sensing device (140) supplies a touch driving signal to the touch electrodes (TE) to drive the touch electrodes (TE) and can sense a change in electrostatic capacity generated when the touch electrodes (TE) are touched through a touch sensing channel. To this end, the touch sensing device (110B) includes a touch raw data generation unit (210) and a touch controller (220). In addition, although not shown in FIG. 2, the touch sensing device (140) may further include a touch driving signal supply unit that supplies a touch driving signal to the touch electrodes (TE) through touch driving lines (TX1 to Txm).

[0055] The touch raw data generation unit (210) generates touch raw data using the sensing values ​​acquired by the plurality of touch sensing channels (RX1 to RXn). Specifically, the touch raw data generation unit (210) can generate initial touch raw data using the initial sensing values ​​acquired by the plurality of touch sensing channels (RX1 to RXn) when there is no touch input from the user when the state of the touch sensing device (140) changes. The initial touch raw data can be used to generate an initial baseline. For example, the state change of the touch sensing device (140) means that the touch sensing device (140) is turned on as the display device (100) is turned on, or that the touch sensing device (140) is turned off as the display device (100) is turned off.

[0056] In addition, the touch low data generation unit (210) generates first touch low data using first sensing values ​​acquired by a plurality of touch sensing channels (RX1 to RXn) when the touch sensing device (140) enters an active mode in which it can sense a touch input by a user. The first touch low data refers to touch low data generated after the initial baseline is set but before the initial baseline is reset.

[0057] In one embodiment, the touch raw data generation unit (210) can obtain sensing values ​​(initial sensing values ​​or first sensing values) obtained by a plurality of touch sensing channels (RX1 to RXn) through differential sensing for adjacent touch sensing channels. For example, the touch raw data generation unit (210) can differentially sense a first touch sensing channel (RX1) and a second touch sensing channel (RX2) among the plurality of touch sensing channels (RX1 to RXn). The touch raw data generation unit (210) according to one embodiment of the present invention can obtain accurate touch sensing results by sensing touch using a differential sensing method, thereby canceling out various noises (induced current and their deviations) generated during touch sensing.

[0058] Hereinafter, a method for generating touch low data through differential sensing by a touch low data generation unit (210) according to the present invention will be described with reference to FIG. 3. Since the method for generating the first touch low data is the same as the method for generating the initial touch low data, for convenience of explanation, the method for generating the initial touch low data by the touch low data generation unit (210) will be described with reference to FIG. 3 below.

[0059] FIG. 3 is a diagram exemplarily showing a differential sensing method of the touch sensing device illustrated in FIG. 2. As illustrated in FIG. 3, a touch raw data generation unit (210) according to one embodiment of the present invention includes a differential amplifier (310), an integrator (320), an analog-to-digital converter (ADC) 330, and an operation unit (340).

[0060] The differential amplifier (310) may include a first input terminal (DI1), a second input terminal (DI2), and an output terminal (DOUT). Although not shown, the differential amplifier (310) may include one or more feedback capacitors. For example, a feedback capacitor may be connected between the first input terminal (DI1) and the output terminal (DOUT), and a feedback capacitor may be connected between the second input terminal (DI2) and the output terminal (DOUT). The differential amplifier (DAMP) may have one or two output terminals (OUT).

[0061] A first input terminal (DI1) of the differential amplifier (310) is electrically connected to a first touch sensing channel (RX1), and a second input terminal (DI2) of the differential amplifier (310) is electrically connected to a first touch sensing channel (RX2). A first electrostatic capacitance value (or a first electrostatic capacitance change value) obtained through the first touch sensing channel (RX1) and a second electrostatic capacitance value (or a second electrostatic capacitance change value) obtained through the second touch sensing channel (RX2) can be input to the differential amplifier (310).

[0062] The touch raw data generation unit (210) may further include a multiplexer circuit (not shown) that selects a first touch sensing channel (RX1) and a second touch sensing channel (RX2) among a plurality of touch sensing channels (RX1 to RXn) and connects them to a first input terminal (DI1) and a second input terminal (DI2) of a differential amplifier (310). The multiplexer circuit may be included within the touch raw data generation unit (210), but may also be mounted on the touch screen panel (112). In this embodiment, the size of the touch sensing device (140) may be reduced.

[0063] The integrator (320) can integrate the differential sensing signal (VOUT) output from the output terminal (DOUT) of the differential amplifier (310) and output an integral value. The analog-to-digital converter (330) converts the integral value output from the integrator (320) into a digital value.

[0064] The operation unit (340) generates initial touch low data by using initial sensing values ​​for a plurality of touch sensing channels (RX1 to RXn) converted into digital values ​​by the analog-to-digital converter (330) for n (n is a natural number greater than or equal to 1) frames. In one embodiment, the operation unit (340) can generate initial touch low data by averaging the initial sensing values ​​for a plurality of touch sensing channels (RX1 to RXn) converted into digital values ​​by the analog-to-digital converter (330) for 3 frames.

[0065] The touch raw data generation unit (210) can provide initial touch raw data including initial sensing values ​​for a plurality of touch sensing channels (RX1 to RXn) to the touch controller (220), thereby allowing the touch controller (220) to generate an initial baseline. In addition, the touch raw data generation unit (210) can provide first touch raw data including first sensing values ​​for a plurality of touch sensing channels (RX1 to RXn) to the touch controller (220), thereby allowing the touch controller (220) to reset the initial baseline or generate touch sensing data including the presence or absence of a touch and / or touch coordinates.

[0066] In addition, the touch raw data generation unit (210) may provide second touch raw data including second sensing values ​​for a plurality of touch sensing channels (RX1 to RXn) to the touch controller (220), thereby allowing the touch controller (220) to reset the first baseline or generate touch sensing data including the presence or absence of a touch and / or touch coordinates.

[0067] Referring again to FIG. 2, the touch controller (220) generates touch sensing data including the presence or absence of a touch and touch coordinates. In particular, the touch controller (220) according to the present invention can reset the baseline used to generate the touch sensing data based on the touch raw data and the baseline. Hereinafter, the touch controller (220) according to the present invention will be described in more detail with reference to FIG. 4.

[0068] FIG. 4 is a block diagram schematically showing the configuration of a touch controller according to one embodiment of the present invention.

[0069] As illustrated in FIG. 4, a touch controller (220) according to one embodiment of the present invention includes a baseline management unit (410) and a touch sensing data generation unit (420), and the baseline management unit (410) includes a baseline generation unit (412), a baseline reset determination unit (414), and a baseline reset unit (416). In addition, the baseline management unit (410) may further include a counter (418).

[0070] The baseline generation unit (412) generates an initial baseline. In one embodiment, the baseline generation unit (412) may generate the initial baseline using initial touch raw data generated when there is no touch input by the user when the state of the touch sensing device (140) changes. That is, the baseline generation unit (412) generates a baseline that does not include noise as the initial baseline. At this time, the initial baseline includes reference values ​​set for each touch sensing channel (RX1 to RXn), and the reference values ​​of each touch sensing channel (RX1 to RXn) may be determined by the initial sensing values ​​of each touch sensing channel (RX1 to RXn) included in the initial touch raw data.

[0071] The baseline reset determination unit (414) determines whether the initial baseline generated by the baseline generation unit (412) or the baseline reset by the baseline reset unit (416) should be reset. That is, if the baseline reset determination unit (414) determines that the initial baseline needs to be reset after the initial baseline is generated, the initial baseline is reset to the first baseline, and if it is determined that the initial baseline does not need to be reset, the initial baseline can be maintained.

[0072] In addition, after the initial baseline is reset to the first baseline by the baseline reset judgment unit (414), if it is determined that the first baseline needs to be reset, the first baseline is reset to the second baseline, and if it is determined that the first baseline does not need to be reset, the first baseline can be maintained.

[0073] The baseline reset determination unit (414) can determine whether to reset the initial baseline by using the first sensing values ​​included in the first touch raw data acquired after the generation of the initial baseline and the reference values ​​included in the initial baseline. In one embodiment, the baseline reset determination unit (414) can determine whether to reset the initial baseline by using the first sensing values ​​of adjacent touch sensing channels in the first touch raw data and the reference values ​​of adjacent touch sensing channels in the initial baseline.

[0074] Specifically, the baseline reset determination unit (414) determines whether to reset the initial baseline by using the first difference value, which is the difference value between the first sensing values ​​of two adjacent touch sensing channels in the first touch low data, and the second difference value, which is the difference value between the reference values ​​of two adjacent touch sensing channels in the initial baseline.

[0075] In addition, the baseline reset determination unit (414) can determine whether to reset the first baseline by using the second sensing values ​​included in the second touch low data newly generated after the first touch low data is generated and the reference values ​​included in the first baseline generated according to the re-establishment of the initial baseline.

[0076] Since the method for resetting the initial baseline and the method for resetting the first baseline are the same, only resetting the initial baseline will be described below for convenience of explanation.

[0077] Hereinafter, with reference to FIG. 5, the method by which the baseline reset determination unit (414) determines whether to reset the initial baseline will be described in more detail. FIG. 5 is a block diagram schematically showing the configuration of the baseline reset determination unit according to one embodiment of the present invention.

[0078] As illustrated in FIG. 5, a baseline reset determination unit (414) according to one embodiment of the present invention includes a first operation unit (510), a second operation unit (520), a third operation unit (530), and a comparison unit (540).

[0079] The first operation unit (510) calculates a first difference value, which is a difference value between the first sensing values ​​of two adjacent touch sensing channels, from the first touch raw data. For example, the first operation unit (510) calculates a first difference value (D1), which is a difference value between the first value (SV1) of the first touch sensing channel (RX1) and the second value (SV2) of the second touch sensing channel (RX2) adjacent to the first touch sensing channel (RX1), from the first touch raw data.

[0080] The second operation unit (520) calculates a second difference value, which is a difference value between the reference values ​​of two adjacent touch sensing channels in the initial baseline. For example, the second operation unit (520) calculates a first difference value (D2), which is a difference value between the first reference value (RV1) of the first touch sensing channel (RX1) and the second reference value (RV2) of the second touch sensing channel (RX2) adjacent to the first touch sensing channel (RX1) in the initial baseline.

[0081] The third operation unit (530) calculates a third difference value, which is a difference value between the first difference value (D1) and the second difference value (D2), for a plurality of touch sensing channels (RX1 to RXn), and calculates a result value (SUM) by adding the third difference values ​​calculated for the plurality of touch sensing channels.

[0082] The comparison unit (540) determines whether to reset the initial baseline using the result value (SUM) produced by the third operation unit (530). In one embodiment, the comparison unit (540) determines to reset the initial baseline if the result value (SUM) produced by the third operation unit (530) is less than a predetermined threshold, and determines to maintain the initial baseline if the result value (SUM) produced by the third operation unit (530) is greater than or equal to the threshold.

[0083] In the above-described embodiment, the threshold value may be set to 0. That is, the comparison unit (540) determines to reset the initial baseline if the result value (SUM) produced by the third operation unit (530) is less than 0 (if it is a negative integer value), and determines to maintain the initial baseline if the result value (SUM) produced by the third operation unit (530) is greater than or equal to the threshold value (if it is a positive integer value).

[0084] Referring back to FIG. 4, the baseline reset unit (416) resets the baseline if the baseline reset determination unit (414) determines that the baseline is to be reset. That is, if the baseline reset determination unit (414) determines that the initial baseline is to be reset, the baseline reset unit (416) resets the initial baseline to the first baseline, and if the baseline reset determination unit (414) determines that the first baseline is to be reset, the first baseline is reset to the second baseline.

[0085] To reset the baseline, the touch low data generation unit (210) generates second touch low data including second sensing values ​​obtained through differential sensing of a plurality of touch sensing channels (RX1 to RXn), and the baseline reset unit (415) generates a first baseline using the second touch low data, thereby resetting the initial baseline to the first baseline. At this time, the second touch low data may also be generated by averaging sensing values ​​obtained for n frames.

[0086] In the above-described embodiment, the baseline reset unit (416) is described as resetting the baseline only when the baseline reset determination unit (414) determines to reset the baseline. However, in a modified embodiment, the baseline reset unit (416) may reset the baseline when the number of times the baseline is determined to be reset by the baseline reset determination unit (414) exceeds a predetermined reference number.

[0087] To this end, the baseline management unit (410) according to the present invention may further include a counter (418). The counter (418) counts up the number of times the baseline has been determined to be reset by the baseline reset determination unit (414) and notifies the result to the baseline reset unit (416). The baseline reset unit (416) resets the baseline when the counted result value exceeds a predetermined reference number.

[0088] In one embodiment, the reference number may be set variably. At this time, the reference number may be set differently depending on the type of display device (100) and the degree of deterioration of the display device (100). For example, if the display device (100) is a device that is frequently touched by the user, such as a mobile device or a game console, the reference number may be set low because noise is likely to be included in the baseline. As another example, if the display device (100) is a TV or monitor that is not frequently touched compared to a mobile device or a game console, the reference number may be set high.

[0089] As another example, when the degree of deterioration of the display device (100) is large, the baseline is likely to contain noise, so the reference number can be set low, and when the degree of deterioration of the display device (100) is small, the baseline is likely to contain noise, so the reference number can be set high.

[0090] In the above-described embodiment, the baseline generation unit (412) and the baseline reset unit (416) are described as separate components, but this is only an example, and the baseline generation unit (412) and the baseline reset unit (416) may be implemented as a single component. For example, the baseline generation unit (412) may perform both the functions of generating an initial baseline and resetting the baseline, or the baseline reset unit (416) may perform both the functions of generating an initial baseline and resetting the baseline.

[0091] As described above, according to the present invention, the baseline management unit (410) determines whether to reset the baseline based on the sensing values ​​of the touch raw data and the reference values ​​of the baseline, and if the baseline needs to be reset, resets the baseline, thereby preventing noise from being included in the baseline in advance, and thereby enabling the user to accurately distinguish and detect a normal touch intended by the user and an abnormal touch not intended by the user.

[0092] The touch sensing data generation unit (420) generates touch sensing data including the presence or absence of a touch and touch coordinates using the baseline provided from the baseline management unit (410) and the touch low data provided from the touch low data generation unit (210). The touch sensing data generation unit (420) transmits the generated touch sensing data to a host system (not shown). That is, when the baseline management unit (410) determines to maintain the initial baseline, the touch sensing data generation unit (420) can generate touch sensing data by comparing the first touch low data provided from the touch low data generation unit (210) with the initial baseline provided from the baseline management unit (410).

[0093] FIG. 6a is a diagram showing an example of touch raw data, FIG. 6b is a diagram showing an example of a baseline, and FIG. 6c is a diagram showing third difference values, which are differences between a first difference value between sensing values ​​of adjacent touch sensing channels in the touch raw data shown in FIG. 6a and a second difference value between reference values ​​of adjacent touch sensing channels in the baseline shown in FIG. 6b.

[0094] Since the result of adding up all the third difference values ​​shown in FIG. 6c is greater than the threshold value of 0, the baseline management unit (410) according to the present invention determines to maintain the baseline shown in FIG. 6b when the touch low data shown in FIG. 6a and the baseline shown in FIG. 6b are acquired.

[0095] FIG. 7a is a diagram showing another example of touch raw data, FIG. 7b is a diagram showing another example of a baseline, and FIG. 7c is a diagram showing third difference values, which are differences between a first difference value between sensing values ​​of adjacent touch sensing channels in the touch raw data shown in FIG. 7a and a second difference value between reference values ​​of adjacent touch sensing channels in the baseline shown in FIG. 7b.

[0096] Since the result of adding up all the third difference values ​​shown in FIG. 7c is less than the threshold value of 0, the baseline management unit (410) according to the present invention determines to reset the baseline shown in FIG. 7b as a new baseline when the touch low data shown in FIG. 7a and the baseline shown in FIG. 7b are acquired.

[0097]

[0098] Hereinafter, a driving method of a touch sensing device according to one embodiment of the present invention will be described with reference to FIG. 8.

[0099] Fig. 8 is a flowchart illustrating a method for driving a touch sensing device according to one embodiment of the present invention. The method for driving the touch sensing device illustrated in Fig. 8 can be applied to the methods for driving the touch sensing devices illustrated in Figs. 1 to 4.

[0100] First, as illustrated in FIG. 8, the touch sensing device (140) generates initial touch raw data including initial sensing values ​​of a plurality of touch sensing channels (RX1 to RXn) (S800). The touch sensing device (140) can generate the touch raw data using the initial sensing values ​​acquired by the plurality of touch sensing channels (RX1 to RXn). At this time, the initial sensing value may be a sensing value generated by the plurality of touch sensing channels (RX1 to RXn) when there is no touch input from the user when the state of the touch sensing device (140) changes. For example, the state change of the touch sensing device (140) may mean that the touch sensing device (140) is turned on as the display device (100) is turned on, or that the touch sensing device (140) is turned off as the display device (100) is turned off.

[0101] In one embodiment, the touch sensing device (140) can obtain initial sensing values ​​of a plurality of touch sensing channels (RX1 to RXn) through differential sensing of adjacent touch sensing channels. For example, the touch sensing device (140) can differentially sense a first touch sensing channel (RX1) and a second touch sensing channel (RX2) among the plurality of touch sensing channels (RX1 to RXn).

[0102] Thereafter, the touch sensing device (140) generates an initial baseline using the initial touch raw data generated in S800 (S810). That is, the touch sensing device (140) can generate an initial baseline using the initial touch raw data generated when there is no touch input by the user when the state of the touch sensing device (140) changes, thereby generating a baseline that does not include noise as the initial baseline. At this time, the initial baseline includes reference values ​​set for each touch sensing channel (RX1 to RXn), and the reference values ​​of each touch sensing channel (RX1 to RXn) can be determined by the initial sensing values ​​of each touch sensing channel (RX1 to RXn) included in the initial touch raw data.

[0103] Thereafter, the touch sensing device (140) generates first touch raw data including first sensing values ​​of a plurality of touch sensing channels (RX1 to RXn) (S820). Specifically, when the touch sensing device (140) enters an active mode in which the touch sensing device (140) can sense a touch input by a user, the touch sensing device (140) generates first touch raw data using the first sensing values ​​acquired by the plurality of touch sensing channels (RX1 to RXn).

[0104] Thereafter, the touch sensing device (140) determines whether to reset the initial baseline (S830). In one embodiment, the touch sensing device (140) may determine whether to reset the initial baseline using a first difference value, which is a difference value between the first sensing values ​​of adjacent touch sensing channels in the first touch raw data, and a second difference value, which is a difference value between the reference values ​​of adjacent touch sensing channels in the initial baseline.

[0105] Specifically, the touch sensing device (140) calculates a first difference value, which is a difference value between the first sensing values ​​of two adjacent touch sensing channels in the first touch raw data, and a second difference value, which is a difference value between the reference values ​​of two adjacent touch sensing channels in the initial baseline. Thereafter, the touch sensing device (140) calculates a third difference value, which is a difference value between the first difference value and the second difference value, for all of the plurality of touch sensing channels, and then calculates a result value by adding the third difference values ​​calculated for the plurality of touch sensing channels. Thereafter, the touch sensing device (140) determines to reset the initial baseline if the result value is less than a predetermined threshold value, and determines to maintain the initial baseline if the result value is greater than or equal to the threshold value. At this time, the threshold value may be set to 0.

[0106] In the above-described embodiment, the two adjacent touch sensing channels may be a first touch sensing channel (RX1) connected to a first touch electrode formed on the touch screen panel and a second touch sensing channel (RX2) connected to a second touch electrode adjacent to the first touch electrode on the touch screen panel.

[0107] Meanwhile, if it is determined to reset the initial baseline in S830, the touch sensing device (140) counts up the number of times it is determined to reset the baseline (S840).

[0108] Thereafter, the touch sensing device (140) determines whether the number of times up-counted in S840 exceeds a preset reference number (S850). In one embodiment, the reference number may be set variably. At this time, the reference number may be set differently depending on the type of the display device (100) and the degree of deterioration of the display device (100). For example, if the display device (100) is a device in which frequent touches by the user occur, such as a mobile device or a game console, the reference number may be set low because noise is likely to be included in the baseline. As another example, if the display device (100) is a TV or a monitor in which touches occur less frequently than in a mobile device or a game console, the reference number may be set high.

[0109] As another example, when the degree of deterioration of the display device (100) is large, the baseline is likely to contain noise, so the reference number can be set low, and when the degree of deterioration of the display device (100) is small, the baseline is likely to contain noise, so the reference number can be set high.

[0110] If the number of times up-counted in S850 exceeds the reference number, the touch sensing device (140) resets the initial baseline (i.e., the existing initial baseline) to the first baseline (i.e., the new baseline) (S860). Specifically, the touch sensing device (140) generates second touch raw data including second sensing values ​​of a plurality of touch sensing channels (RX1 to RXn), and generates the first baseline using the second touch raw data, thereby resetting the initial baseline to the first baseline.

[0111] Meanwhile, if it is determined in S830 not to reset the initial baseline, or if the number of up-counts in S850 does not exceed the reference number, the touch sensing device (140) determines to maintain the initial baseline (S870). If the touch sensing device (140) determines to maintain the initial baseline, it can compare the first touch raw data with the initial baseline, generate touch sensing data including touch coordinates, and transmit the generated touch sensing data to the host system.

[0112] Those skilled in the art will appreciate that the present invention described above can be implemented in other specific forms without changing the technical idea or essential features thereof.

[0113] Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included within the scope of the present invention.

Claims

1. A touch raw data generation unit that generates first touch raw data including first sensing values ​​obtained through differential sensing of a plurality of touch sensing channels; A baseline reset determination unit that determines whether to reset the initial baseline by using the first sensing values ​​of adjacent touch sensing channels in the first touch raw data and the reference values ​​of the adjacent touch sensing channels in the predetermined initial baseline; and A touch sensing device including a baseline reset unit that resets the initial baseline using second touch raw data including second sensing values ​​obtained through differential sensing of the plurality of touch sensing channels when it is determined that the initial baseline is to be reset.

2. In paragraph 1, The above baseline reset judgment unit, A first operation unit that calculates a first difference value, which is a difference value between the first sensing values ​​of the adjacent touch sensing channels, from the first touch raw data; A second operation unit for calculating a second difference value, which is a difference value between reference values ​​of adjacent touch sensing channels from the initial baseline; A third operation unit that calculates a third difference value, which is a difference value between the first difference value and the second difference value, for the plurality of touch sensing channels and calculates a result value by summing the third difference values ​​calculated for the plurality of touch sensing channels; and A touch sensing device including a comparison unit that determines whether to reset the initial baseline using the above result value.

3. In paragraph 2, The above comparison section is, A touch sensing device that determines to reset the initial baseline if the result value is less than a predetermined threshold, and determines to maintain the initial baseline if the result value exceeds the threshold.

4. In paragraph 3, A touch sensing device wherein the above threshold is set to 0.

5. In paragraph 1, Further comprising a counter for determining the number of times the initial baseline is determined to be reset by the baseline reset determination unit, The above baseline reset unit is a touch sensing device that resets the initial baseline when the number of times counted by the counter exceeds a predetermined reference number.

6. In paragraph 1, A touch sensing device further comprising a baseline generation unit that generates the initial baseline using initial touch raw data including initial sensing values ​​generated from the plurality of touch sensing channels when there is no touch input from the user when the state of the touch sensing device changes.

7. In paragraph 1, A touch sensing device wherein the adjacent touch sensing channels are a first touch sensing channel connected to a first touch electrode on a touch screen panel and a second touch sensing channel connected to a second touch electrode adjacent to the first touch electrode on the touch screen panel.

8. In paragraph 1, A touch sensing device further comprising a touch sensing data generation unit that generates touch sensing data including touch coordinates by comparing the first touch low data with the initial baseline when it is determined by the baseline reset determination unit that the initial baseline is maintained.

9. Step of generating an initial baseline using the initial touch low data; A step of generating first touch raw data including first sensing values ​​of a plurality of touch sensing channels; A step of determining whether to reset the initial baseline by using a first difference value, which is a difference value between first sensing values ​​of adjacent touch sensing channels in the first touch raw data, and a second difference value, which is a difference value between reference values ​​of adjacent touch sensing channels in the initial baseline; If it is determined to reset the initial baseline, generating second touch raw data including second sensing values ​​of the plurality of touch sensing channels; and A method for driving a touch sensing device, comprising the step of resetting the initial baseline using the second touch low data.

10. In paragraph 9, The step to determine whether to reset the above is A step of calculating the first difference value and the second difference value; A step of calculating a third difference value, which is a difference value between the first difference value and the second difference value, for the plurality of touch sensing channels; A step of calculating a result value by adding up the third difference values ​​calculated for the plurality of touch sensing channels; and A method for driving a touch sensing device, comprising the step of determining to reset the initial baseline if the result value is less than a predetermined threshold, and determining to maintain the initial baseline if the result value exceeds the threshold.

11. In paragraph 10, A method for driving a touch sensing device, wherein the above threshold is set to 0.

12. In paragraph 9, After the step of determining whether to reset, the step of counting the number of times the initial baseline is determined to be reset is further included. A method for driving a touch sensing device that resets the initial baseline when the counted number of times exceeds a predetermined reference number in the step of resetting the initial baseline.

13. In paragraph 9, If it is determined that the initial baseline is maintained in the step of determining whether to reset the above, A method for driving a touch sensing device, further comprising the step of generating touch sensing data including touch coordinates by comparing the first touch raw data with the initial baseline.

14. In paragraph 9, A method for driving a touch sensing device, wherein the initial touch raw data includes initial sensing values ​​generated from the plurality of touch sensing channels when there is no user touch input when the state of the touch sensing device changes.

15. In paragraph 9, A method for driving a touch sensing device, wherein the above-described adjacent touch sensing channels are a first touch sensing channel connected to a first touch electrode formed on a touch screen panel and a second touch sensing channel connected to a second touch electrode adjacent to the first touch electrode on the touch screen panel.

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