KR20130063973A - Apparatus and method for driving touch sensor - Google Patents

Abstract

PURPOSE: A touch sensor operating device and a method thereof are provided to minimize a threshold value for touch determination and noise elements according to an environmental change by determining a touch based on data of a static frame. CONSTITUTION: A touch controller(30) determines a touch by using data of a static frame and a dynamic frame based on a readout signal and calculates and outputs touch coordinates according to the determination result. The data of the dynamic frame is a difference value between raw data of a current frame and raw data of a previous frame based on the readout signal. The data of the static frame is a difference value between the raw data of the current frame and raw data of a reference frame detected from raw data at specific time. [Reference numerals] (12) Data driver; (14) Gate driver; (18) Timing controller; (30) Touch controller; (50) Host computer

Description

TECHNICAL FIELD [0001] The present invention relates to an apparatus and a method for driving a touch sensor,

The present invention relates to a touch sensor driving apparatus and method, and more particularly, to a touch sensor driving apparatus and method capable of improving a touch sensing force by minimizing noise due to environmental changes.

2. Description of the Related Art Today, a touch sensor capable of inputting information by touching on a screen of various display devices is widely applied as an information input device of a computer system. The touch sensor allows the user to easily use the display information by simply touching the screen with a finger or a stylus to select or move the display information.

The touch sensor driving device senses a touch and a touch position generated by the touch sensor on the display device and outputs touch information, and the computer system analyzes the touch information and performs an instruction. As a display device, a flat panel display device such as a liquid crystal display device, a plasma display panel, and an organic light emitting diode display device is mainly used. As the touch sensor technology, there are resistance film type, capacitive type, optical type, infrared type, ultrasonic type, and electromagnetic type depending on the sensing principle.

The touch sensor may be constituted by an on-cell touch sensor manufactured in the form of a panel and attached to the upper part of the display device, or an in-cell touch sensor built in a pixel matrix of the display device ). As a touch sensor, a photo-touch sensor that recognizes a touch according to light intensity using a phototransistor and a capacitive touch sensor that recognizes a touch according to a capacitive variable are mainly used.

Generally, in a touch sensor driving apparatus, a lead-out IC (Integrated Circuit) drives a touch sensor and detects row data using a read-out signal received from a touch sensor. A micro control unit (MCU), which is a signal processor, compares raw data with a reference value to determine whether or not there is touch, calculates touch coordinates, and transmits the touch coordinates to the host computer. The host computer executes commands corresponding to the touch coordinates.

The conventional MCU compares the row data of the current frame with the row data when there is no touch and judges whether the touch is compared with a preset reference frame, thereby reducing the noise effect. However, when the raw data varies according to the change of the external environment such as the residual image noise after the touch or the temperature change of the touch sensor, the touch may not be sensed despite the actual touch due to the variable noise component, There is a problem of deterioration.

In addition, since the reference frame is set from the raw data when there is no touch after turning on the power of the touch sensor, the reliability of the touch sensing can not be secured at the initial operation time when the reference frame is not set.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-described problems of the related art, and it is an object of the present invention to provide a touch sensing device capable of minimizing noise by determining whether a touch is made using a static frame and a dynamic frame, And to provide a sensor driving apparatus and method.

According to an aspect of the present invention, there is provided a touch sensor driving apparatus including: a touch sensor; A touch controller that determines whether or not the touch is made using data of at least one frame out of data of a dynamic frame based on a lead-out signal from the touch sensor and data of a static frame, calculates touch coordinates according to the determination result, Respectively.

Wherein the data of the dynamic frame is a difference value between the row data of the previous frame based on the readout signal and the row data of the current frame and the data of the static frame is the difference value of the reference frame detected from the row data of the non- Is the difference value between the row data and the row data of the current frame.

The row data of the reference frame is updated when it is determined that at least one of the case where the power of the touch sensor is turned on and the case where the state without touch is maintained for a certain period of time.

The touch controller includes: a touch sensor driver for driving the touch sensor; A readout circuit for detecting and outputting row data of the current frame using a readout signal from the touch sensor; And a signal processor for determining whether or not the touch is made and calculating touch coordinates.

The signal processor comprising: a memory for storing row data of the previous frame and row data of the reference frame; A memory controller for controlling reading and writing of the memory; A first comparator for comparing the row data of the previous frame input from the memory via the memory controller with the row data of the current frame to detect the dynamic frame; A second comparator for comparing the row data of the reference frame input from the memory via the memory controller with the row data of the current frame to detect the static frame; And a touch detection unit for calculating and outputting the touch determination and touch coordinates using the dynamic frame and the row data of the static frame from the first and second comparators, The touch detection unit outputs the touch coordinates to the memory controller to be stored in the memory.

Wherein the touch detection unit compares data of the dynamic frame with a preset threshold value to determine whether or not a first touch peak that is equal to or greater than the threshold value is detected, and when the first touch peak is detected, calculates the touch coordinates with respect to the first touch peak And outputs it.

If the first touch peak is not detected in the determination whether the dynamic frame is touched, the touch detection unit detects a touch in a previous frame using the touch coordinates of a previous frame stored in the memory, And if it is judged that the touch is held, judges whether or not a second touch peak having a threshold value or more is detected by comparing the static frame with a threshold value, and if the second touch peak is detected, Calculates second touch coordinates for the touch peak, compares the touch coordinates of the previous frame with the second touch coordinates, and calculates and outputs second touch coordinates that are the same as or adjacent to the touch coordinates of the previous frame as final touch coordinates .

The touch detection unit determines that the second touch coordinates are not detected or that the second touch coordinates adjacent to the touch coordinates of the previous frame are not detected.

A method of driving a touch sensor according to an embodiment of the present invention includes detecting and storing data of a dynamic frame based on a readout signal from a touch sensor and data of a static frame; Determining whether or not to touch the data using the data of the dynamic frame and data of the static frame, and calculating and outputting the touch coordinates according to the determination result.

Wherein the step of calculating the touch coordinates comprises: storing row data of the previous frame and row data of the reference frame; Comparing the row data of the previous frame with the row data of the current frame to detect the dynamic frame; Comparing the row data of the reference frame with the row data of the current frame to detect the static frame; Calculating and outputting the touch determination and touch coordinates using the dynamic data and the static data of the static frame; And storing the touch coordinates.

The step of calculating the touch coordinates may include comparing the data of the dynamic frame with a preset threshold value to determine whether or not a first touch peak of the threshold value or more is detected and if the first touch peak is detected, And calculating and outputting the touch coordinates.

The step of calculating the touch coordinates may include detecting a touch in the previous frame using the touch coordinates of the stored previous frame if the first touch peak is not detected in the determination of whether or not to use the dynamic frame, Determining whether or not the second touch peak is detected; comparing the static frame with a threshold value to determine whether or not a second touch peak having a threshold value or higher is detected; and if the second touch peak is detected Calculating second touch coordinates of the second touch peak by comparing the touch coordinates of the previous frame with the second touch coordinates and comparing the second touch coordinates of the previous frame with the touch coordinates of the previous frame as a final touch And outputting the calculated coordinates.

The step of calculating the touch coordinates may further include determining whether the second touch coordinates are not detected or the second touch coordinates adjacent to the touch coordinates of the previous frame are not detected.

The apparatus and method for driving a touch sensor according to the present invention are characterized in that data of a dynamic frame, which is difference data between row data of a previous frame and row data of a current frame, data of a row of a reference frame, It is possible to minimize the noise component due to the environmental change and the threshold value for the touch judgment by using the data of the static frame which is the difference data and judge whether or not the touch is made. In addition, the touch sensing ability and the reliability can be improved by double judgment.

1 is a block diagram showing a configuration of a display device including a touch sensor driving apparatus according to an embodiment of the present invention.
FIG. 2 is a view showing a structure of the touch sensor shown in FIG. 1, for example.
3 is a block diagram showing a touch sensor driving apparatus according to an embodiment of the present invention.
4 is a block diagram showing an internal configuration of the MCU shown in FIG.
FIG. 5 is a three-dimensional graph showing, for example, a dynamic frame used in the present invention.
FIG. 6 is a three-dimensional graph showing an example of a static frame used in the present invention.
FIG. 7 is a dimensional graph showing, for example, a dynamic frame in the case of touch holding used in the present invention.

FIG. 1 is a block diagram showing a configuration of a display device including a touch sensor driving device according to an embodiment of the present invention. FIG. 2 is a diagram showing the structure of the touch sensor 20 shown in FIG.

1 includes a display panel 10, a panel driver 16 including a data driver 12 and a gate driver 14 for driving the display panel 10, A timing controller 18 for controlling the driving unit 16, a touch sensor 20 on the display panel 10 and a touch controller 30 for driving the touch sensor 20. The timing controller 18 and the touch controller 30 are connected to the host computer 50.

The timing controller 18 and the data driver 12 may be integrated into respective integrated circuits (ICs), or the timing controller 18 may be embedded in the data drivers 12 and integrated into one IC. The touch controller 30 and the timing controller 18 may be integrated into respective ICs or the touch controller 30 may be embedded in the timing controller 18 and integrated into one IC.

The display panel 10 includes a pixel array in which a plurality of pixels are arranged. The pixel array displays a graphical user interface (GUI) and other images including pointers or cursors. As the display panel 10, a flat panel display panel such as a liquid crystal display panel (hereinafter referred to as a liquid crystal panel), a plasma display panel, and an organic light emitting diode display panel can be mainly used. Hereinafter, a liquid crystal panel will be described as an example.

When a liquid crystal panel is used as the display panel 10, the display panel 10 includes a color filter substrate on which a color filter array is formed, a thin film transistor substrate on which a thin film transistor array is formed, a liquid crystal layer between the color filter substrate and the thin film transistor substrate And a polarizing plate attached to the outer surfaces of the color filter substrate and the thin film transistor substrate, respectively. The display panel 10 displays an image through a pixel matrix in which a plurality of pixels are arranged. Each pixel implements a desired color by a combination of red, green, and blue sub-pixels that adjust the light transmittance by varying the liquid crystal array according to the data signal. Each sub pixel includes a thin film transistor TFT connected to the gate line GL and the data line DL, a liquid crystal capacitor Clc connected in parallel with the thin film transistor TFT, and a storage capacitor Cst. The liquid crystal capacitor Clc charges the difference voltage between the data signal supplied to the pixel electrode through the thin film transistor TFT and the common voltage Vcom supplied to the common electrode, drives the liquid crystal according to the charged voltage, . The storage capacitor Cst stably maintains the voltage charged in the liquid crystal capacitor Clc. The liquid crystal layer is driven by a vertical electric field such as a TN (Twisted Nematic) mode or VA (Vertical Alignment) mode, or by a horizontal electric field such as an IPS (In-Plane Switching) mode or an FFS (Fringe Field Switching) mode.

The data driver 12 supplies video data from the timing controller 18 to a plurality of data lines DL of the display panel 10 in response to a data control signal from the timing controller 18. [ The data driver 12 converts the digital data input from the timing controller 18 into a positive / negative analog data signal by using a gamma voltage, and outputs a data signal to the data line DL). The data driver 12 includes at least one data IC and is mounted on a circuit film such as TCP, COF, FPC or the like to be attached to the display panel 10 by TAB (Tape Automatic Bonding) On the display panel 10 as shown in Fig.

The gate driver 14 sequentially drives the plurality of gate lines GL formed in the thin film transistor array of the display panel 10 in response to the gate control signal from the timing controller 18. [ The gate driver 14 supplies the gate-on voltage during a corresponding scan period of each gate line GL and supplies the gate-off voltage during the remaining period during which the other gate line GL is driven. The gate driver 14 includes at least one gate IC and is mounted on a circuit film such as a tape carrier package (TCP), a chip on film (COF), or a flexible printed circuit (FPC) Automatic bonding, or may be mounted on the display panel 10 in a COG (Chip On Glass) manner. In addition, the gate driver 14 may be embedded in the display panel 10 in a GIP (Gate In Panel) manner and formed on the thin film transistor substrate together with the pixel array.

The timing controller 18 processes the video data input from the host computer 50 and supplies the video data to the data driver 12. [ For example, in order to improve the response speed of the liquid crystal, the timing controller 18 corrects the data by overdriving driving to add an overshoot value or an undershoot value according to the data difference between adjacent frames, can do. The timing controller 18 is connected to the data driver 12 using a plurality of synchronizing signals input from the host computer 50, that is, a vertical synchronizing signal Vsync, a horizontal synchronizing signal Hsync, a data enable signal, ) And a gate control signal for controlling the driving timing of the gate driver 14 are generated. The timing controller 18 outputs the generated data control signal and gate control signal to the data driver 12 and the gate driver 14, respectively. The data control signal includes a source start pulse and a source sampling clock for controlling the latch of the data signal, a polarity control signal for controlling the polarity of the data signal, and a source output enable signal for controlling the output period of the data signal. The gate control signal includes a gate start pulse and gate shift clock for controlling the scanning of the gate signal, a gate output enable signal for controlling the output period of the gate signal, and the like. The timing controller 18 supplies the synchronizing signal (the vertical synchronizing signal Vsync and the horizontal synchronizing signal Hsync) to the touch controller 30 and controls the driving timing of the liquid crystal panel 10 and the driving timing of the touch sensor 20 So that the operation timing of the touch controller 30 can be controlled.

The touch sensor 20 detects a user touch and allows the user to talk with the GUI displayed on the display panel 10. [ The touch sensor 20 mainly uses a capacitive type touch sensor that recognizes a touch by sensing a change in capacitance caused by a small amount of charge moving to a touch point when a conductor such as a human body or a stylus is touched. The touch sensor 20 may be mounted on the display panel 10 or embedded in the pixel array of the display panel 10. [

For example, the capacitive touch sensor 20 attached on the display panel 10 may include a plurality of first sensing electrodes 22 disposed in the lateral direction as shown in FIG. 2, A plurality of lead-out lines (or reception lines) RX1 to RXm (or RX1 to RXm) in which a plurality of second sensing electrodes 24 arranged in the longitudinal direction are electrically connected to each other, ). Each of the first and second sensing electrodes 22 and 24 is mainly formed in a rhombic shape and may be formed in various other shapes. The first and second sensing electrodes 22 and 24 are driven by the touch controller 30 to form a capacitance by a fringe field and a capacitor with a conductive touch object touching the touch sensor 20 And outputs a readout signal indicating whether or not the touch is made to the touch controller 30 by changing the capacitance.

The touch controller 30 supplies a driving signal to the scan lines TX1 to TXN of the touch sensor 20 and also generates a touch signal by using a read out signal outputted from the lead- out lines RX1 to RXm of the touch sensor 20. [ Determines whether or not to touch each node (by channel), calculates the touch coordinates according to the result, and supplies the coordinate to the host computer 50.

The touch controller 30 converts the readout signals received for each channel from the lead-out lines RX1 to RXm into digital low data every time the scan lines TX1 to TXN of the touch sensor 20 are driven, And outputs low data. The touch controller 30 receives the data of the dynamic frame which is the difference data between the row data of the previous frame and the row data of the current frame and the difference data between the row data of the reference frame and the row data of the current frame, And the touch coordinates are calculated and output to the host computer 50 according to the determination result. The reference frame is set to the low-level data at a specific time when there is no touch, or is set using the low-level data. The touch controller 30 compares the dynamic frame, which is difference data between the row data of the previous frame and the row data of the current frame, with the threshold value to detect whether or not it is touched, thereby minimizing the threshold for noise and touch detection due to environmental changes. When the touch is held, the touch controller 30 compares the static frame, which is difference data between the row data of the reference frame and the row data of the current frame, with the threshold value, The reliability of the touch judgment can be improved. A concrete touch detection method of the touch controller 30 will be described later.

The host computer 50 supplies image data and a plurality of synchronizing signals to the timing controller 18, analyzes the touch coordinates inputted from the touch controller 30, and executes a command corresponding to the touch operation of the user.

FIG. 3 is a block diagram showing the configuration of a touch sensor driving apparatus according to an embodiment of the present invention, and FIG. 4 is a block diagram showing an internal configuration of the MCU shown in FIG.

3, the touch controller 30 connected to the touch sensor 20 includes a lead-out circuit 32, a touch sensor driver 34, and an MCU (MicroController Unit) 36.

The touch sensor driver 34 supplies driving pulses in a line sequential manner to the scan lines TX1 to TXn (FIG. 2) of the touch sensor 20 in response to the control of the MCU 40. [

The lead-out circuit 32 uses the lead-out signal output from the lead-out lines RX1 to RXm (FIG. 2) each time a drive pulse is supplied to the scan lines TX1 to TXn of the touch sensor 20, Detects star row data. To this end, the lead-out circuit 32 includes a sensing unit (amplifier) and an analog-to-digital converter (ADC). The sense amplifier amplifies the readout signal from the touch sensor 20 with a preset reference voltage, amplifies the voltage over the reference voltage, and outputs the amplified voltage as a sensing signal. The ADC converts the analog sensing signal from the sensing unit to digital low data and outputs the digital low data to the MCU 40.

The MCU 40, which is a signal processor, compares the row data of the current frame from the lead-out circuit 32 with the row data of the previous frame and the reference frame respectively to detect the dynamic frame and the static frame, And determines whether or not the touch is made according to the comparison result. The touch coordinates are calculated according to the determination result and supplied to the host computer 50 (FIG. 1).

4, the MCU 40 includes a memory 42 for storing dynamic frames and static frames, a memory controller 44 for controlling read / write of the memory 42, A second comparator 48 for detecting a static frame and a second comparator 46 for detecting a random noise from the data of the dynamic frame and the static frame of the first and second comparators 46 and 48, And a dynamic frame and a static frame from the first and second noise filters 62 and 64 to determine whether or not the touch is detected and to detect the touch coordinates using the first and second noise filters 62 and 64, And a touch detection unit 66 for detecting the touch.

The reference frame and the row data of the previous frame are stored in the memory 42 via the memory controller 44. The reference frame consists of the low-level data at a specific time detected when there is no touch. Meanwhile, the reference frame may be set as an average value of row data collected for each touch node during a plurality of frames without touch, or may be set as a calculation result value using an average value, a minimum value, a maximum value, and the like of the collected row data. The memory controller 44 is adaptively arranged every time the power is turned on and / or when a touch is not detected for a predetermined time (i.e., when the touch detection data is not input from the touch detection unit 66 for a predetermined time) The reference frame is reset and the memory 42 is updated. The initial reference frame may be preset and stored by the designer in accordance with the unique characteristics such as the design and the driving conditions of the touch sensor 20. [

The first comparator 46 compares the row data of the current frame input from the readout circuit 32 with the row data of the previous frame input from the memory 42 via the memory controller 44, Similarly, a dynamic frame composed of the difference between the row data of the previous frame and the row data of the current frame is detected and output to the first noise filter 62.

The second comparator 48 compares the row data of the current frame with the reference frame input from the memory 42 through the memory controller 44 as shown in FIG. 6, And outputs the detected static frame to the second noise filter 64. The second noise filter 64 detects the static frame,

The first and second noise filters 62 and 64 remove the random noise (or white noise) components remaining in the data of the dynamic frame and the static frame from the first and second comparators 46 and 48, respectively, And outputs it to the detection unit 66. [

The touch detection unit 66 judges whether the dynamic frame and the static frame inputted through the first and second comparators 46 and 48 via the first and second noise filters 62 and 64 are touched in a double manner, And calculates and outputs the touch coordinates according to the determination result.

Specifically, the touch detection unit 66 compares the dynamic frame detected as the difference between the row data of the previous frame and the row data of the current frame with a threshold value to determine whether or not a touch peak is detected as a threshold value or more. And transmits the touch coordinates to the host computer 50 and stores the touch coordinates in the memory 42 via the memory controller 44. [ Since the touch detecting unit 66 detects whether or not the touch is detected using the dynamic frame which is the difference between the row data of the previous frame and the row data of the current frame as described above, the residual image noise after touching or the temperature change of the touch sensor 20 The threshold value for noise and touch detection due to environmental changes such as a change in row data according to the threshold value can be minimized.

7, since the touch can not be detected using only the dynamic frame, which is the data difference between the previous frame and the current frame, the touch detection unit 66 uses the dynamic frame and the static frame And judges whether or not the touch is double.

The touch detection unit 66 compares the dynamic frame with a threshold value to determine whether or not a touch peak having a threshold value or more is detected, and if the touch peak is not detected, the touch coordinate of the previous frame supplied from the memory 42 through the memory controller 44 is , It is determined whether or not the touch coordinate is detected in the previous frame and the touch is detected in the current frame. The touch detection unit 66 compares the static frame detected as the difference between the row data of the current frame and the row data of the reference frame to a threshold value to determine whether or not the touch peak is detected as a threshold value or more, The second touch coordinates indicating the touch peak are detected. Also, the touch detection unit 66 compares the touch coordinates of the previous frame with the second touch coordinates to determine whether or not the touch is secondarily performed. The touch detecting unit 66 compares the touch coordinates of the previous frame with the second touch coordinates and detects the second touch coordinates determined to be the same or adjacent to the touch coordinates of the previous frame, And outputs it to the memory controller 44.

On the other hand, if the second touch coordinates are not detected or the detected second touch coordinates are not adjacent to the touch coordinates of the previous frame, that is, if the detected touch coordinates are not touch holding, the touch detecting unit 66 determines that the touch coordinates are not touch, I never do that.

If the touch is not detected using the dynamic frame, the touch detection unit 66 may determine whether the touch is doubly performed using the static frame, thereby improving the reliability of the touch determination.

Accordingly, the touch detecting unit 66 determines whether or not the touch is held first by using the data of the dynamic frame, and further determines whether the touch is held by using the data of the static frame.

As described above, the apparatus and method for operating a touch sensor according to the present invention are capable of generating data of a dynamic frame, which is difference data between row data of a previous frame and row data of a current frame, raw data of a reference frame, It is possible to minimize the noise component due to the environmental change and the threshold value for the touch judgment by using the data of the static frame which is difference data with the low data of the touch screen, have.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of.

10: liquid crystal panel 12: data driver
14: gate driver 16: panel driver
18: timing controller 20: touch sensor
22: first sensing electrode 24: second sensing electrode
30: touch controller 32: lead-out circuit
34: touch sensor driving unit 40: MCU
42: memory 44: memory controller
46, 48: Comparator 62, 64: Noise filter
66: touch detection unit 50: host computer

Claims (15)

A touch sensor;
A touch controller that determines whether or not the touch is made using data of at least one frame out of data of a dynamic frame based on a lead-out signal from the touch sensor and data of a static frame, calculates touch coordinates according to the determination result, Wherein the touch sensor is a touch sensor. The method according to claim 1,
The data of the dynamic frame is a difference value between the row data of the previous frame based on the readout signal and the row data of the current frame,
Wherein the data of the static frame is a difference value between the row data of the reference frame detected from the row data of the specific time without touch and the row data of the current frame. The method of claim 2,
Wherein the reference data of the reference frame is updated when it is determined that at least one of the case where the power of the touch sensor is turned on and the case where the state without touch is maintained for a predetermined time. The method of claim 2,
The touch controller
A touch sensor driver for driving the touch sensor;
A readout circuit for detecting and outputting row data of the current frame using a readout signal from the touch sensor;
And a signal processor for determining whether the touch is made and calculating touch coordinates. The method of claim 4,
The signal processor
A memory for storing row data of the previous frame and row data of the reference frame;
A memory controller for controlling reading and writing of the memory;
A first comparator for comparing the row data of the previous frame input from the memory via the memory controller with the row data of the current frame to detect the dynamic frame;
A second comparator for comparing the row data of the reference frame input from the memory via the memory controller with the row data of the current frame to detect the static frame;
And a touch detection unit for calculating and outputting the touch determination and touch coordinates using the dynamic frame and the row data of the static frame from the first and second comparators,
Wherein the touch detection unit outputs the touch coordinates to the memory controller so as to be stored in the memory. The method of claim 5,
The touch detection unit
Comparing the data of the dynamic frame with a preset threshold value to determine whether or not a first touch peak having a threshold value or more is detected and if the first touch peak is detected, calculating the touch coordinates for the first touch peak and outputting Wherein the touch sensor driving device comprises: The method of claim 6,
The touch detection unit
If the first touch peak is not detected in the determination as to whether the touch is made using the dynamic frame,
Determining whether a touch is detected in a previous frame using the touch coordinates of a previous frame stored in the memory and a touch is not detected in a current frame,
Determining whether or not the second touch peak having the threshold value or more is detected by comparing the static frame with a threshold value if it is determined to be the touch holding state and if the second touch peak is detected, Respectively,
And comparing the touch coordinates of the previous frame with the second touch coordinates to calculate a second touch coordinate that is the same as or adjacent to the touch coordinates of the previous frame as final touch coordinates and outputs the calculated final touch coordinates. The method of claim 7,
The touch detection unit
When the second touch coordinates are not detected or when the second touch coordinates adjacent to the touch coordinates of the previous frame are not detected, Detecting and storing data of a dynamic frame based on a lead-out signal from a touch sensor and data of a static frame;
Determining whether or not a touch is made using data of the dynamic frame and data of at least one frame of data of the static frame, and calculating and outputting touch coordinates according to the determination result. The method of claim 9,
The data of the dynamic frame is a difference value between the row data of the previous frame based on the readout signal and the row data of the current frame,
Wherein the data of the static frame is a difference value between the row data of the reference frame detected from the row data of the specific time without touch and the row data of the current frame. The method of claim 10,
Wherein the row data of the reference frame is updated when it is determined that at least one of the case where the power of the touch sensor is turned on and the case where the state without touch is maintained for a predetermined time. The method of claim 10,
The step of calculating the touch coordinates
Storing the row data of the previous frame and the row data of the reference frame;
Comparing the row data of the previous frame with the row data of the current frame to detect the dynamic frame;
Comparing the row data of the reference frame with the row data of the current frame to detect the static frame;
Calculating and outputting the touch determination and touch coordinates using the dynamic data and the static data of the static frame;
And storing the touch coordinates. The method of claim 12,
The step of calculating the touch coordinates
Comparing the data of the dynamic frame with a preset threshold value to determine whether or not a first touch peak of the threshold value or more is detected and if the first touch peak is detected, calculating and outputting the touch coordinates of the first touch peak Wherein the touch sensor is a touch sensor. 14. The method of claim 13,
The step of calculating the touch coordinates
If it is determined that the first touch peak is not detected in the determination as to whether the dynamic frame is used, it is determined whether the touch is detected in the previous frame using the touch coordinates of the stored previous frame, Determining,
Determining whether or not the second touch peak having the threshold value or more is detected by comparing the static frame with a threshold value if it is determined to be the touch holding state and if the second touch peak is detected, Calculating,
And comparing the touch coordinates of the previous frame with the second touch coordinates to calculate a second touch coordinate which is the same as or adjacent to the touch coordinates of the previous frame as final touch coordinates and outputting the result. Driving method. 15. The method of claim 14,
The step of calculating the touch coordinates
Further comprising the step of determining whether the second touch coordinates are not detected or when the second touch coordinates adjacent to the touch coordinates of the previous frame are not detected.

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