KR102210216B1 - Apparatus for Driving of Touch Screen - Google Patents

Abstract

The present invention relates to a touch screen driving apparatus capable of improving touch sensing performance in an edge region of a touch screen.
According to an embodiment of the present invention, an apparatus for driving a touch screen includes: a touch driving unit that supplies driving signals to a plurality of driving (Tx) lines of the touch screen; A touch sensing unit sensing touch signals of a plurality of sensing (Rx) lines of the touch screen; And a touch algorithm execution unit that compensates for a touch signal of an edge region of the touch screen.

Description

Apparatus for Driving of Touch Screen}

The present invention relates to a driving device for a touch screen capable of improving touch sensing performance in an edge region of a touch screen.

The touch screen is installed in an image display device such as a liquid crystal display device, a field emission display device, a plasma display device, an electroluminescent display device, an electrophoretic display device, and an organic light-emitting display device, so that the user can use a finger or a pen while looking at the display device. It is a type of input device that directly contacts the screen to input information.

In recent years, touch screens have been commercialized as input devices for portable information devices such as smart phones and tablet PCs, notebook computers, monitors, and various electronic devices such as televisions.

Such a touch screen may be implemented in a capacitive manner. The capacitive touch screen senses a touch input by sensing a change in capacitance, that is, an amount of change in charge of the touch sensor when a finger or a conductive material contacts the touch sensor. The capacitance method is divided into a mutual capacitance method and a self capacitance method. The mutual capacitive touch panel has an advantage in that it is possible to implement a multi-touch input compared to the self capacitive type.

1 is a diagram showing the structure of a general touch screen.

Referring to FIG. 1, the touch interface has been supported since version 8.0 of MS Windows, and it is recommended to form an electrode of the touch screen and a driving device of the touch screen so as to guarantee a touch accuracy within 1 mm at the edge of the active area. have.

In general, in order to improve touch accuracy at the edge portion, the outermost node of the touch screen is positioned outside the active area, so that a lot of reference data of raw data for calculating the center coordinates can be obtained. As an example, in order to ensure a touch accuracy of less than 1 mm at the edge portion, a dummy touch electrode 20 is formed outside the active area by an area corresponding to a 1/2 channel of the touch electrode 10 formed in the active area. .

2 is a diagram illustrating a structure of an in-cell touch type touch screen.

Referring to FIG. 2, when a touch screen is formed in an in-cell touch method on a liquid crystal display device or an organic light emitting display device, there is a limitation in extending the touch electrode outside the active area.

In the in-cell touch method, a plurality of touch groups TB1 to TBn are formed by patterning electrodes formed inside cells of a display panel to a predetermined size. In addition, a touch screen is configured by dividing and connecting a plurality of touch groups into a driving (TX) electrode and a sensing (RX) electrode.

Recently, a narrow bezel technology that reduces or minimizes a bezel area of a display panel has been applied. The bezel area is formed outside the active area (A/A) of the display panel to define an active area. The active area A/A includes a pixel array in which an input image is displayed. Since pixels are not formed in the bezel area, an image is not displayed.

If the bezel area of the display panel is narrowed, the center of the touch area may be incorrectly calculated in the edge area of the display panel. The edge area is an edge area of the touch screen close to the bezel area, and refers to an area in which the center of the touch area is incorrectly calculated.

3 is a diagram illustrating a problem in that touch sensing accuracy is lowered in an edge region of a touch screen.

Referring to FIG. 3, touch electrodes are not formed in the bezel area of the display panel, or the area of the touch electrodes is significantly smaller than that of an active area (A/A). The touch node located at the outermost edge of the edge area reduces the sensitivity of the touch signal by about 25% compared to other touch nodes.

Due to the structural limitation of the in-cell touch type touch screen, the touch signal in the edge area decreases rapidly, and the difference in the touch signal occurs due to the difference in RC values between the touch electrodes. In addition, in the in-cell touch method, the parasitic capacitor increases compared to the add-on touch method, so that touch deviation due to noise occurs. In particular, touch deviation due to noise occurs severely in the edge region.

Accordingly, if a touch is sensed in the same manner without considering the difference in the touch screen structure between the active area A/A and the edge area of the display panel, there is a problem in that the accuracy of touch sensing is deteriorated. As the bezel of the display panel gets narrower, the error in touch sensing becomes more serious.

The present invention has been made to solve the above-described problem, and it is an object of the present invention to provide a touch screen driving device capable of improving the touch sensing performance of an in-cell touch type touch screen.

The present invention has been made to solve the above-described problem, and it is an object of the present invention to provide a touch screen driving apparatus capable of improving touch sensing performance in an edge region of a touch screen.

The present invention is to solve the above-described problem, and it is an object of the present invention to provide a driving device for a touch screen capable of improving touch sensing performance without additionally forming a touch electrode in a bezel region of a display device.

In addition to the technical problems of the present invention mentioned above, other features and advantages of the present invention will be described below or will be clearly understood by those of ordinary skill in the art from such technology and description.

A driving apparatus for a touch screen according to an embodiment of the present invention for achieving the above-described technical problem includes: a touch driver for supplying a driving signal to a plurality of driving (Tx) lines of the touch screen; A touch sensing unit sensing touch signals of a plurality of sensing (Rx) lines of the touch screen; And a touch algorithm execution unit that compensates for a touch signal of an edge region of the touch screen.

The touch algorithm execution unit of the driving apparatus of a touch screen according to an embodiment of the present invention includes an infinite impulse response filter (IIR), and removes noise from a touch signal in an edge region of the touch screen using the IIR filter.

The touch algorithm execution unit of the driving apparatus of a touch screen according to an embodiment of the present invention includes a signal flattening unit, and compensates for signal deviations of the plurality of sensing (Rx) lines and driving (Tx) lines with the signal flattening unit.

The signal flattening unit of the driving device of the touch screen according to an embodiment of the present invention compensates for signal deviations of the plurality of sensing (Rx) lines to 5% or less, and compensates for the signal deviations of the plurality of driving (Tx) lines by 3%. Compensate for the following.

The touch algorithm execution unit of the driving apparatus of a touch screen according to an embodiment of the present invention includes an edge signal compensation unit, and the edge signal compensation unit compensates for a touch signal reduced by an area of a touch electrode in the edge area.

The touch algorithm execution unit of the driving apparatus of the touch screen according to an embodiment of the present invention includes a touch coordinate correction unit, and the touch coordinate correction unit corrects touch coordinates sensed in the edge area.

The driving device of a touch screen according to an embodiment of the present invention may improve touch sensing performance of an in-cell touch type touch screen.

The driving device of a touch screen according to an embodiment of the present invention may improve touch sensing performance in an edge area of the touch screen.

The driving device of a touch screen according to an embodiment of the present invention can improve touch sensing performance without additionally forming a touch electrode in a bezel area of the display device.

The driving device of a touch screen according to an exemplary embodiment of the present invention enables uniform touch sensing performance to be maintained regardless of the direction of an edge area of the touch screen.

In addition, other features and advantages of the present invention may be newly recognized through embodiments of the present invention.

1 is a diagram showing the structure of a general touch screen.
2 is a diagram illustrating a structure of an in-cell touch type touch screen.
3 is a diagram illustrating a problem in that touch sensing accuracy is lowered in an edge area of a touch screen.
4 is a diagram schematically illustrating a display device to which a driving device for a touch screen is applied according to an embodiment of the present invention.
5 is a diagram illustrating an electrode structure of the touch screen shown in FIG. 4.
6 is a diagram for explaining that a difference in sensing size occurs when an active area and an edge area are touched.
7 is a diagram illustrating a driving device of a touch screen according to an embodiment of the present invention.
8 to 10 are diagrams illustrating a method of driving a driving apparatus for a touch screen according to an exemplary embodiment of the present invention.
11 is a diagram illustrating various devices to which a driving device of a touch screen according to an embodiment of the present invention is applicable.

Hereinafter, a driving apparatus for a touch screen according to the present invention will be described in detail with reference to the accompanying drawings. The same reference numbers throughout the specification mean substantially the same elements. In the following description, when not related to the core configuration of the present invention and detailed descriptions of configurations and functions known in the technical field of the present invention may be omitted.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms different from each other, and only these embodiments make the disclosure of the present invention complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have it, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are exemplary, and the present invention is not limited to the illustrated matters. The same reference numerals refer to the same components throughout the specification. In addition, in describing the present invention, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. When'include','have','consists of' and the like mentioned in the present specification are used, other parts may be added unless'only' is used. In the case of expressing the constituent elements in the singular, it includes the case of including the plural unless specifically stated otherwise.

In interpreting the components, even if there is no explicit description, it is interpreted as including an error range. Each of the features of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each of the embodiments can be implemented independently of each other or can be implemented together in a related relationship. May be.

4 is a diagram schematically illustrating a display device to which a driving device for a touch screen is applied according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the display device includes a display panel 300, driving circuit units 310, 320, and 330 of the display panel, a touch screen 100, and a touch driving device 200. The touch screen 100 may be applied to a display device in an add-on, on-cell, or in-cell manner. The driving circuit units 310, 320, 330 of the display panel include a timing controller 310, a gate driver 320, and a data driver 330. Since the display panel 300 and the driving circuit units 310, 320, and 330 of the display panel are well known, detailed descriptions thereof will be omitted.

5 is a diagram illustrating an electrode structure of the touch screen shown in FIG. 4.

Referring to FIG. 4 with reference to FIG. 5, the touch screen 100 includes a plurality of driving (Tx) lines and a plurality of sensing (Rx) lines crossing the plurality of driving (Tx) lines. Mutual capacitance is formed at nodes at a point where the driving (Tx) lines and the sensing (Rx) lines cross each other.

The driving (Tx) lines and the sensing (Rx) lines cross each other with an insulating layer therebetween, and a bridge pattern is formed at the point where the driving (Tx) lines and the sensing (Rx) lines cross each other. The driving (Tx) lines or the sensing (Rx) lines are connected to each other.

The driving device of the touch screen senses the amount of charge change in the touch electrode before and after the touch, and determines whether a conductive material such as a finger is touched and its location. The driving device of the touch screen supplies a driving signal to the driving (Tx) lines, and receives electric charges from the touch sensors through the sensing (Rx) lines in synchronization with the driving signal. Thereafter, the presence or absence of a touch and a touch position are determined by sensing a change amount of the electric charge received from the sensing (Rx) lines. In this case, the driving signal applied to the driving (Tx) lines may be generated in various forms such as a square wave type pulse, a sine wave, and a triangular wave.

6 is a diagram for explaining that a difference in sensing size occurs when an active area and an edge area are touched.

Referring to FIG. 6, the physical sizes of the first touch area T1 sensed in the edge area adjacent to the bezel area and the second touch area T2 sensed in the active area are the same. However, there is a difference between the size of the touch sensed in the first touch area T1 and the size of the touch sensed in the second touch area T2.

Here, the physical size means the size of the area touched by the touch object, and the sensing size means the size of the touch area sensed by the touch sensors. Since the first touch area T1 of the edge area is positioned between the bezel area and the active area, the sensing size when a touch is applied to the edge area is smaller than that when a touch is applied to the active area.

The driving apparatus of a touch screen according to the present invention improves touch sensing performance in an edge area of the touch screen.

7 is a diagram illustrating a driving device of a touch screen according to an embodiment of the present invention.

Referring to FIG. 7, a driving device 200 for a touch screen according to an embodiment of the present invention supplies a driving signal to driving (Tx) lines, and in synchronization with the driving signal, a touch sensor through sensing (Rx) lines It receives the signal of (Cm).

In order to compare the received charge change amount of the touch sensor Cm with a predetermined threshold value, the driving device 200 of the touch screen converts the charge change amount into a digital value and outputs touch raw data. The driving device 200 of the touch screen compares the touch row data with the threshold value and determines the touch row data larger than the threshold value as the touch region data. The driving device 200 of the touch screen executes a labeling algorithm that assigns a label code to each of the touch regions for multi-touch recognition. Subsequently, the center of gravity of each of the touch areas is calculated, and a touch report (XY) including coordinate information of the touch area is transmitted to the host system based on the center of gravity of the touch area.

Here, when the touch area is sensed in the edge area of the display panel, the driving device 200 of the touch screen improves the SNR of the touch signal received in the edge area, removes the deviation of the touch signal, removes the noise of the touch signal, and between the touch nodes. By compensating for touch signal deviations, touch sensing performance in the edge area is improved.

To this end, the driving apparatus 200 for a touch screen according to an embodiment of the present invention includes a touch driver 210, a touch sensing unit 220, a touch timing controller 230, and a touch algorithm execution unit 240.

The touch driver 210, the touch sensing unit 220, and the touch timing controller 230 may be integrated into a single readout integrated circuit (ROIC) chip. In addition, the touch algorithm execution unit 240 may be implemented as a microcontroller unit (MCU).

The touch driver 210 selects a Tx channel to which a driving signal is to be supplied under the control of the touch timing controller 230 and supplies a driving signal to the driving (Tx) lines Tx1 to Txj connected to the selected Tx channel.

The touch sensing unit 220 senses a touch signal through a driving (Tx) line, that is, senses electric charge of the touch sensor. The touch sensing unit 220 may include an integrator, and if charges of the touch sensor are accumulated in the integrator, the amount of charge change may be increased before and after a touch input, thereby increasing touch sensing sensitivity. As shown in FIG. 5, differential amplifiers may be connected between the sensing (Rx) lines Rx1 to Rxi and the touch sensing unit 220. Differential amplifiers improve a signal-to-noise ratio (SNR) of a touch signal by amplifying a difference between touch signals received through neighboring sensing (Rx) lines to increase a component of a touch signal versus noise.

The touch sensing unit 220 converts the sampled digital data using an analog to digital converter (ADC) and senses the amount of change in charge of the touch sensor. The digital data is transmitted to the touch algorithm execution unit 240 as touch raw data.

The touch timing controller 230 controls signal input and output of the Tx/Rx channel of the touch driver 210 and the touch sensing unit 220. In addition, the touch timing controller 230 controls the sampling of the touch sensor signal of the touch sensing unit 220 and controls the driving timing of the ADC.

Subsequently, the touch algorithm execution unit 240 includes an IIR filter 241 (infinite impulse response filter), a signal flattening unit 242, an edge signal compensation unit 243, a touch presence/absence determination unit 244, a labeling unit 245, A touch center calculation unit 246, a touch area tracking unit 247, a touch coordinate correction unit 248, and a flat filter 249 are included.

The IIR filter 241 removes high frequency noise included in the touch signal (touch row data) of the edge region, and prevents the touch signal of the edge region from becoming unstable due to the high frequency noise.

The signal flattening unit 242 removes or reduces a signal deviation between a plurality of Rx channels and a signal deviation between Tx channels. It compensates for the deviation between each channel (node) based on the maximum signal among the driving (Tx) lines and the sensing (Rx) lines. In order to distinguish between the signal and the noise, the compensation is performed on data of a predetermined signal or more. In this case, the signal flattening unit 242 flattens the signals of all regions except for the nodes of the edge regions, so that the compensation of the touch signals of the edge nodes can be concisely performed.

Here, the signal deviation of all sensing (Rx) lines is compensated so that the signal deviation of all sensing (Rx) lines is 5% or less. In addition, the signal deviation of all the driving (Tx) lines is compensated so that the signal deviation of all the driving (Tx) lines is 3% or less.

The edge signal compensating unit 243 reduces the reduction of the touch signal caused by the area of the touch sensor, that is, the area of the touch electrode being formed smaller than the area of the touch sensor in the active area in the edge areas formed on the four sides of the touch screen. Compensate. The edge signal compensating unit 243 compensates for a decrease in the touch signal due to the physically small shape of the touch sensor in the edge region by the narrow bezel. In this case, the touch signal in the edge area may be compensated for at the level of the touch sensor in the active area.

The touch presence/absence determination unit 244 determines whether all nodes are touched based on the touch sensing result of the entire Rx channel. In this case, a node in which the touch has been made and a node in which the touch has not been made are distinguished. In addition, 0 is assigned to a node that has not been touched with a 2-bit value, and 1 is assigned to a node where a touch is made to indicate the presence or absence of touches of all nodes.

When the multi-touch is sensed, the labeling unit 245 assigns a number to the nodes in which the touch has been made in order to identify each of the multi-touched touch nodes. If a single touch is sensed, a number may not be assigned to the node where the touch was made.

The touch center calculation unit 246 calculates the center of the touch point touched by the user by analyzing the touch signals of all nodes included in the touch point touched by the user.

The touch area tracking unit 247 tracks the positions of each of the multi-touch areas based on the center of the touch point when multi-touch is performed. If a single touch is sensed, it is not necessary to distinguish the positions of a plurality of touch areas where a touch has been made.

The touch coordinate correction unit 248 improves the accuracy of touch sensing by performing correction of touch coordinates in an adaptive manner according to the touch area of the edge area. When a touch is made to the edge area, the amount of touch row data that can know the touch coordinates is very small in the bezel area, and the amount of touch row data is relatively large in the active area. Touch coordinates may not be detected.

In order to improve this problem, the touch coordinate correction unit 248 performs correction of the touch coordinates by generating a look-up table (LUT) for correcting the edge coordinates.

As an example, in order to set the location information (a, b) of the edge area according to the size of the touch area, the total data of the touch area is calculated. In addition, the calculation result of the total data of the touch area is input into the lookup table LUT so that position information (a, b) of the edge area can be selected.

In the memory of the lookup table (LUT), as shown in Table 1 below, location information (a, b) of the edge region is stored for each total of the touch row data of the touch region. The lookup table LUT may receive the total of the touch row data of the touch area as read address information and output location information (a, b) indicated by the total of the touch row data of the touch area.

Size of touch area Location information (a) Location information (b) Touch area
Total touch row data φ9 0.75 0.35 3,500~5,000 φ5 0.50 0.10 1,000-1,800

In this way, by using the touch coordinate correction unit 248 to correct the touch coordinates according to the touch area of the edge area, even when a touch is made to the edge area, the touch coordinates can be accurately detected.

The flat filter 249 may be applied with a digital filter and improves the touch sensing performance of each sensing (Rx) line by flattening the touch signal sensed by the sensing (Rx) line.

8 to 10 are diagrams illustrating a method of driving a driving apparatus for a touch screen according to an exemplary embodiment of the present invention.

When the user's touch is detected, it is checked whether the touch signal of the edge node is input (S10).

As a result of checking S10, if the touch signal of the edge node is not input, the touch is made only in the active area. In this case, a touch sensing result report is generated by applying a general touch sensing method. Thereafter, the touch sensing result report is transmitted to the host system (S90).

Meanwhile, as a result of checking in S10, when the touch signal of the edge node is input, the high-frequency noise included in the touch signal (touch row data) of the edge region is removed using the IIR filter 241 (S20). This prevents the touch signal of the edge region from becoming unstable due to high frequency noise.

Subsequently, the signal deviation between the plurality of Rx channels and the signal deviation between the Tx channels are sequentially removed or reduced.

As shown in FIG. 9, in all Rx channels of the touch screen, a signal deviation of about 1.25 times occurs between the line with the highest signal and the line with the lowest signal. The signal flattening unit 242 compensates for a signal deviation of all the sensing (Rx) lines based on the sensing (Rx) line of the maximum signal among the sensing (Rx) lines (S30). At this time, compensation is performed on data of a certain signal or more in order to distinguish between the signal and noise. The signal deviation of all sensing (Rx) lines is compensated so that the signal deviation of all sensing (Rx) lines is less than 5%. In this way, by flattening the signals of the sensing (Rx) lines, the compensation of the touch signal of the edge node may be performed simply.

Subsequently, as shown in FIG. 10, in all driving (Tx) channels of the touch screen, a signal deviation of about 1.05 times occurs between the line with the highest signal and the line with the lowest signal. The signal flattening unit 242 compensates for the signal deviation of all the driving (Tx) lines based on the driving (Tx) line of the maximum signal among the driving (Tx) lines (S40). At this time, compensation is performed on data of a certain signal or more in order to distinguish between the signal and noise. The signal deviation of all sensing (Rx) lines is compensated so that the signal deviation of all driving (Tx) lines is less than 3%. In this way, by flattening the signals of the driving (Tx) lines, the compensation of the touch signal of the edge node can be performed simply.

Subsequently, the touch signal of the edge node is improved (S50). It compensates for a decrease in touch signal generated by forming the area of the touch sensor, that is, the area of the touch electrode smaller than the area of the touch sensor in the active area, in the edge areas formed on the four sides of the touch screen. Specifically, the edge signal compensating unit 243 compensates for a decrease in the touch signal due to the physically small shape of the touch sensor in the edge region by the narrow bezel. In this case, the touch signal in the edge area may be compensated for at the level of the touch sensor in the active area.

Subsequently, in order to identify each touch node that has been multi-touched, a number is assigned to the nodes where the touch has been made, the center of the touch point touched by the user is calculated, and the location of each of the multi-touch areas is tracked (S60).

Subsequently, touch coordinates are corrected in an adaptive manner according to the touch area of the edge area (S70). In this way, the accuracy of touch sensing is improved by correcting the touch coordinates of the edge area.

As an example, a look-up table (LUT) for edge coordinate correction is generated using the touch coordinate correction unit 248 to correct touch coordinates (S70).

In order to set the location information (a, b) of the edge area for each size of the touch area, the total data of the touch area is calculated. In addition, the calculation result of the total data of the touch area is input into the lookup table LUT so that position information (a, b) of the edge area can be selected. Position information (a, b) indicated by the total number of touch row data of the touch area recorded in the look-up table (LUT) may be output.

Subsequently, the touch signal sensed on the sensing (Rx) line is flattened using a flat filter to improve the touch sensing performance of each sensing (Rx) line (S80).

The apparatus for driving a touch screen according to an embodiment of the present invention described above may improve touch sensing performance of an in-cell touch type touch screen. In particular, the driving device of a touch screen according to an embodiment of the present invention may improve touch sensing performance in an edge area of the touch screen.

In addition, the driving device of a touch screen according to an embodiment of the present invention can improve touch sensing performance without additionally forming a touch electrode in the bezel area of the display device. Therefore, it is possible to improve the touch sensing performance of the edge area without additional burden of cost.

In addition, the driving device of a touch screen according to an embodiment of the present invention enables uniform touch sensing performance to be maintained regardless of the direction of the edge area of the touch screen.

11 is a diagram illustrating various devices to which a driving device of a touch screen according to an embodiment of the present invention is applicable.

Referring to FIG. 11, an apparatus for driving a touch screen according to an embodiment of the present invention may be applied to driving a touch screen of a flexible display apparatus. In the smart watch and the flexible display device, the screen is bent, and accordingly, the touch screen is also bent. In this case, in the area where the touch screen is bent, the performance of touch sensing may deteriorate. Like the edge region described above, noise and distortion occur in the touch signal in the region where the touch screen is bent, resulting in deterioration of touch sensing performance. When sensing the touch of the bent area of the touch screen, applying the touch algorithm in the driving device and the edge area of the touch screen described above can improve the touch sensing performance of the bent area of the touch screen.

Those skilled in the art to which the present invention pertains will be able to understand that the above-described present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof.

Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting. The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. do.

100: touch screen
200: driving device of the touch screen
210: touch driver
220: touch sensing unit
230: touch timing control unit
240: touch algorithm execution unit
241: IIR filter
242: signal flattening unit
243: edge signal compensation unit
244: touch presence/absence determination unit
245: labeling unit
246: touch center calculation unit
247: touch area tracking unit
248: touch coordinate correction unit
249: flat filter
300: display panel
310: timing controller
320: gate driver
330: data driver

Claims (6)

A touch driver for supplying driving signals to a plurality of driving (Tx) lines of the touch screen;
A touch sensing unit sensing touch signals of a plurality of sensing (Rx) lines of the touch screen; And
And a touch algorithm execution unit compensating for a touch signal of an edge region of the touch screen,
The touch algorithm execution unit includes a signal flattening unit for compensating for signal deviations of the plurality of sensing (Rx) lines and driving (Tx) lines,
The signal flattening unit,
A driving device of a touch screen for compensating for a signal deviation in all areas except for the node of the edge area based on a maximum signal among the plurality of sensing (Rx) lines and driving (Tx) lines. The method of claim 1,
The touch algorithm execution unit includes an IIR filter (infinite impulse response filter), and the IIR filter is used to remove noise from a touch signal in an edge region of the touch screen. delete The method of claim 1,
The signal flattening unit compensates for signal deviations of the plurality of sensing (Rx) lines to 5% or less and compensates for signal deviations of the plurality of driving (Tx) lines to less than 3%. The method of claim 1,
The touch algorithm execution unit includes an edge signal compensation unit, and the edge signal compensation unit compensates for a touch signal reduced by an area of a touch electrode in the edge area. The method of claim 1,
The touch algorithm execution unit includes a touch coordinate correction unit, and the touch coordinate correction unit corrects touch coordinates sensed in the edge area.

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