KR102501018B1 - Touch Screen Device - Google Patents

Abstract

An object of the present invention is to provide a touch screen device capable of accurately determining the presence or absence of a touch in an idle mode without increasing the size of a touch driver. To this end, the touch screen device according to the present invention detects whether or not a touch has been touched based on a difference between first and second touch raw data calculated by sensing one touch electrode twice during a touch sensing period of one frame period in an idle mode. By making the determination, it is possible to remove the baseline deviation existing in the touch screen device, so that it is possible to accurately determine whether or not there is a touch. In addition, the touch screen device according to the present invention stores first touch row data obtained in idle mode in a first buffer used for updating touch row data in normal mode, and maintains touch row data in normal mode. Since the second touch row data obtained in the idle mode is stored in the used second buffer, an additional frame memory or buffer is not required, and thus the size of the touch driver can be minimized.

Description

Touch Screen Device {Touch Screen Device}

The present invention relates to a touch screen device.

Various input devices such as a keyboard, a mouse, a track ball, a joystick, a digitizer, and the like are used to configure an interface between a user and various electronic devices. Accordingly, demand for an input device that is convenient, simple, and capable of reducing malfunctions is increasing day by day.

In response to such a demand, a touch screen device in which a user inputs information by directly contacting a screen with a hand or a pen has been proposed. A touch screen device can input information simply by touching a button displayed on a display unit with a finger, so that anyone of any age or gender can easily use the touch screen device.

The touch screen device is driven in an idle mode to reduce power consumption when there is no user input for a predetermined period of time. When the touch screen device is operating in an idle mode, the touch screen device wakes up when a touch of a predetermined pattern is sensed. When the touch screen device senses a touch in idle mode, as shown in FIG. ) and, as shown in FIG. 1(b), when the touch raw data exceeding the touch threshold exceeds a predetermined repeat time threshold, it is determined that a touch has occurred.

However, since the baseline of the touch screen device is not uniform, in the touch sensing method in idle mode as shown in FIG. There is a problem in that it is impossible to accurately determine the presence or absence of a touch.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a touch screen device capable of accurately determining the presence or absence of a touch in an idle mode without increasing the size of a touch driver.

A touch screen device according to an aspect of the present invention for achieving the above object is a display panel including touch electrodes that also serve as a common electrode, a blank period during idle mode driving, and driving and sensing the touch electrodes. A touch driver for alternating a first touch sensing period and alternating a display driving period for supplying a common voltage to touch electrodes during normal mode driving and a second touch sensing period for driving and sensing the touch electrodes do. The touch driver includes a plurality of touch voltage sensing units configured to sense the voltage charged in each of the touch electrodes twice during the first touch sensing period of the idle mode to calculate a first output voltage and a second output voltage, and each touch voltage sensing unit. Analog-to-digital conversion of generating first touch raw data by digitally converting the first output voltage output from each touch voltage sensor and generating second touch raw data by digitally converting the second output voltage output from each touch voltage sensing unit; A multiplexer that sequentially connects the touch voltage sensing unit to the analog-to-digital conversion unit, a control signal generation unit that generates a channel selection signal for connecting each touch voltage sensing unit to the analog-to-digital conversion unit and supplies it to the multiplexer, and first touch raw data and and a touch determination unit that determines whether there is a touch based on the second touch raw data. Each of the plurality of touch voltage sensing units continuously supplies a pair of first and second driving pulse patterns to each touch electrode during the first touch sensing period of the idle mode, and before another touch electrode is driven, each touch electrode is driven. The voltage charged in the electrode is sensed twice to continuously calculate the first and second output voltages, and during the second touch sensing period in the normal mode, each third drive pulse pattern is supplied to each touch electrode and each touch electrode A third output voltage may be calculated by sensing the charged voltage. The control signal generation unit continuously supplies a pair of first and second pulses as channel selection signals when the multiplexer selects each touch voltage sensing unit connected to the analog-to-digital conversion unit during the first touch sensing period of the idle mode, During the second touch sensing period of the normal mode, when the multiplexer selects each touch voltage sensing unit connected to the analog-to-digital conversion unit, a third pulse may be supplied as a channel selection signal.

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According to the present invention, since the presence or absence of a touch is determined based on a difference between first and second touch raw data calculated by sensing one touch electrode twice during a touch sensing period of one frame period in an idle mode, the touch screen It is possible to remove the baseline deviation existing in the device, so that the presence or absence of a touch can be accurately determined.

Further, according to the present invention, first touch raw data obtained during the touch sensing period of the idle mode is stored in a first buffer used for updating the touch raw data acquired during the touch sensing period of the normal mode, Since the second touch raw data acquired during the touch sensing period of the idle mode is stored in the second buffer used to maintain the touch raw data acquired during the touch sensing period of the normal mode, the first touch raw data and the second touch raw data are stored. There is an effect that the size of the touch driver can be minimized because an additional frame memory or buffer is not required to calculate the difference value between touch row data.

1 is a diagram conceptually showing a general touch sensing method in an idle mode.
2 is a block diagram showing in detail a touch screen device according to an embodiment of the present invention.
FIG. 3 is an exemplary diagram illustrating pixels, touch electrodes, touch driving lines, and a touch driver of the display panel of FIG. 2 .
FIG. 4 is an exemplary diagram showing the pixels of FIG. 3 in detail.
5 is a waveform diagram showing signals supplied to touch driving lines during one frame period in a normal mode.
6 is a waveform diagram showing signals supplied to touch driving lines during one frame period in an idle mode.
7 is a block diagram showing the configuration of a touch driver according to an embodiment of the present invention.
FIG. 8 is a circuit diagram showing the configuration of the touch voltage sensing unit shown in FIG. 7 .
FIG. 9 is a block diagram showing the configuration of a touch presence determination unit shown in FIG. 7 .
FIG. 10( a ) is a diagram showing a waveform of a channel selection signal in a normal mode generated by the control signal generator shown in FIG. 7 .
FIG. 10( b ) is a diagram showing a waveform of a channel selection signal in an idle mode generated by the control signal generator shown in FIG. 7 .
11(a) is a diagram illustrating a sensing operation of a touch voltage sensing unit according to a channel selection signal and a touch driving voltage.
11(b) is a diagram illustrating a sensing operation of a touch voltage sensing unit according to a channel selection signal, a first touch driving voltage, and a second touch driving voltage.
12 and 13 are views showing data stored in a first buffer and a second buffer according to another embodiment of the present invention.
14 is a diagram conceptually showing a touch sensing method in an idle mode according to the present invention.
15A and 15B are flowcharts illustrating a touch driving method of a touch screen device according to an embodiment of the present invention.

The meaning of terms described in this specification should be understood as follows.

Singular expressions should be understood to include plural expressions unless the context clearly defines otherwise, and terms such as “first” and “second” are used to distinguish one component from another, The scope of rights should not be limited by these terms.

It should be understood that terms such as "comprise" or "having" do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

The term “at least one” should be understood to include all possible combinations from one or more related items. For example, "at least one of the first item, the second item, and the third item" means not only the first item, the second item, or the third item, but also two of the first item, the second item, and the third item. It means a combination of all items that can be presented from one or more.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing a touch screen device according to an embodiment of the present invention. FIG. 3 is an exemplary diagram illustrating pixels, touch electrodes, touch driving lines, and a touch driver of the display panel of FIG. 2 . FIG. 4 is an exemplary view showing the pixels of FIG. 3 in detail. Hereinafter, a touch screen device according to an embodiment of the present invention will be schematically described in conjunction with FIGS. 2 to 4 .

The touch screen device according to an embodiment of the present invention has been described mainly as being implemented in a self capacitance (self capacitance) method, but is not limited thereto. That is, the touch screen device according to an embodiment of the present invention can be implemented with other capacitance methods such as a mutual capacitance method.

In addition, the touch screen device according to an embodiment of the present invention has been described based on an in-cell type implementation in which touch electrodes are included in the display panel 10, but is not limited thereto. That is, the touch screen device according to an embodiment of the present invention may be implemented as an on-cell type in which touch electrodes are provided on the display panel 10 .

Furthermore, the touch screen device according to an embodiment of the present invention has been described mainly as a liquid crystal display (LCD), but is not limited thereto. That is, the touch screen device according to an embodiment of the present invention may be implemented as an organic light emitting display (OLED), a plasma display device, or an electrophoresis display device.

As shown in FIG. 2, the touch screen device according to an embodiment of the present invention includes a display panel 10, a gate driver 20, a data driver 30, a timing controller 40, a touch driver 50, and a touch coordinate calculator. (60), and a main processor (70).

The display panel 10 includes a lower substrate, an upper substrate, and a liquid crystal layer interposed between the lower and upper substrates. On the lower substrate of the display panel 10, data lines (D1 to Dm, where m is a positive integer greater than or equal to 2), gate lines (G1 to Gn, where n is a positive integer greater than or equal to 2), and touch driving lines C1 ~ Cp, p is a positive integer of 2 or more) is formed. The data lines D1 to Dm and the touch driving lines C1 to Cp may cross the gate lines G1 to Gn.

Pixels P may be formed at intersections of the data lines D1 to Dm and the gate lines G1 to Gn, as shown in FIG. 2 . Each of the pixels P may be connected to a data line and a gate line. Each of the pixels P may include a transistor T, a pixel electrode 11, a liquid crystal cell 13, and a storage capacitor Cst, as shown in FIG. 4 . The transistor T is turned on by the gate signal of the kth gate line Gk (k is a positive integer satisfying 1≤k≤n), and the jth (j is a positive integer satisfying 1≤j≤m). An integer of) The data voltage of the data line Dj is supplied to the pixel electrode 11 . The touch electrode 12 receives a common voltage from one of the touch driving lines C1 to Cp (Cq). When a common voltage is supplied to the touch electrode 12, the touch electrode 12 serves as a common electrode. Due to this, each of the pixels P drives the liquid crystal of the liquid crystal cell 13 by an electric field generated by a potential difference between the data voltage supplied to the pixel electrode 11 and the common voltage supplied to the touch electrode 12. A transmission amount of light incident from the backlight unit may be adjusted. As a result, the pixels P can display images. In addition, the storage capacitor Cst is provided between the pixel electrode 11 and the touch electrode 12 to maintain a constant voltage difference between the pixel electrode 11 and the touch electrode 12 .

A plurality of touch electrodes 12 are formed on the display panel 10 as shown in FIG. 3 . Each of the touch electrodes 12 may be formed to overlap with s (s is a positive integer greater than or equal to 2) number of pixels. For example, the size of the touch electrode 12 may be set in consideration of a contact area of a finger and a contact area of a pen.

Each of the touch electrodes 12 may be connected to one of the touch driving lines C1 to Cp as shown in FIG. 3 . Each of the touch driving lines C1 to Cp connects each of the touch electrodes 12 and the touch driver 50 . When the touch screen operates in a normal mode, as shown in FIG. 5 , the touch electrodes 12 transmit the display drive period DP from the touch driver 50 through the touch drive lines C1 to Cp. During the touch sensing period TP, the common voltage Vcom may be supplied, and the touch driving voltages VD1 to VDp may be supplied during the touch sensing period TP. When the common voltage Vcom is supplied to the touch electrodes 12, the touch electrodes 12 serve as a common electrode.

In addition, when the touch screen operates in idle mode, as shown in FIG. 6 , during the touch sensing period (TP), the touch electrodes 12 are connected to the touch driver 50 through the touch driving lines C1 to Cp. ) is supplied with touch driving voltages (VD1 to VDp).

In particular, when the touch screen operates in idle mode, each touch electrode 12 according to the present invention, as shown in FIG. 6 , during the touch sensing period TP, the first touch driving voltage VDA1 ~VDAp) and second touch driving voltages (VDB1 to VDBp) are sequentially supplied. Accordingly, the touch electrodes 12 according to the present invention are sensed twice during the touch sensing period TP of the idle mode.

The touch driving lines C1 to Cp may be disposed between two adjacent pixels as shown in FIG. 3 .

A black matrix and a color filter may be formed on the upper substrate of the display panel 10 . However, when the display panel 10 is formed of a color filter on TFT (COT) structure, the black matrix and color filters may be formed on a lower substrate of the display panel 10 .

A polarizer is attached to each of the upper and lower substrates of the display panel 10, and an alignment layer for setting a pre-tilt angle of liquid crystal is formed. A column spacer is formed between the upper substrate and the lower substrate of the display panel 10 to maintain a cell gap of the liquid crystal cell.

A backlight unit may be disposed under the rear surface of the lower substrate of the display panel 10 . The backlight unit is implemented as an edge type or direct type backlight unit and irradiates light to the display panel 10 .

The gate driver 20 generates gate signals according to the gate control signal GCS input from the timing controller 40 . The gate driver 20 supplies gate signals to the gate lines G1 to Gn in a predetermined order during the display driving period DP in the normal mode. The predetermined order may be a sequential order. The gate driver 20 does not supply gate signals to the gate lines G1 to Gn during the touch sensing period TP of the normal mode and the idle mode.

In another embodiment, the gate driver 20 adjusts the touch driving voltages VD1 to VDp and the touch driving voltages VD1 to VDp in order to remove the influence of the touch driving voltages VD1 to VDp applied to the touch electrodes during the touch sensing period TP of the normal mode. Gate signals having the same frequency and the same swing width may be supplied to each of the gate lines G1 to Gn.

The data driver 30 receives digital video data DATA and a data control signal DCS from the timing controller 40 . The data driver 30 converts the digital video data DATA into analog data voltages according to the data control signal DCS. The data driver 30 supplies data voltages to the data lines D1 to Dm during the display driving period DP in the normal mode. The data driver 30 does not supply data voltages to the data lines D1 to Dm during the touch sensing period TP of the normal mode and the idle mode.

In another embodiment, the data driver 30 controls the touch driving voltages (VD1 to VDp) and the touch driving voltages (VD1 to VDp) in order to remove the influence of the touch driving voltages (VD1 to VDp) applied to the touch electrodes during the touch sensing period (TP) of the normal mode. Data control signals having the same frequency and the same swing width may be supplied to each of the data lines D1 to Dm.

The timing controller 40 receives digital video data DATA and timing signals TS from the main processor 70 . The timing signals TS may include a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, a dot clock, and the like. The vertical synchronization signal is a signal defining one frame period. The horizontal synchronization signal is a signal defining one horizontal period for supplying data voltages to pixels of one horizontal line of the display panel 10 . Pixels of one horizontal line can be connected to the same gate line. The data enable signal is a signal defining a period during which valid digital video data is supplied. The dot clock is a signal that is briefly repeated at a predetermined cycle.

The timing controller 40 receives the idle mode control signal IMS from the main processor 70 . The timing controller 40 operates the gate driver 20 and the data driver 30 in a normal mode when an idle mode control signal IMS having a first logic level is input. As shown in FIG. 5 , the timing controller 40 divides one frame period into a display driving period (DP) and a touch sensing period (TP), and the gate driving unit 20 during the display driving period (DP). ) supplies gate signals to the gate lines G1 to Gn, and controls the data driver 30 to supply data voltages to the data lines D1 to Dm. 5 illustrates that one frame period includes one display driving period DP and one touch sensing period TP, but is not limited thereto. That is, one frame period may include a plurality of display driving periods DP and a plurality of touch sensing periods TP.

The timing controller 40 includes a gate control signal GCS for controlling the operation timing of the gate driver 20 and a data control signal for controlling the operation timing of the data driver 30 based on the timing signals in the normal mode. DCS). The timing controller 40 outputs the gate control signal GCS to the gate driver 20 and outputs digital video data DATA and data control signal DCS to the data driver 30 in normal mode.

The timing controller 40 may generate a mode signal MODE to distinguish between the display driving period DP and the touch sensing period TP in the normal mode. The timing controller 40 may output the mode signal MODE to the touch driver 50 .

The touch driver 50 operates in an idle mode when an idle mode control signal IMS having a second logic level is input. The timing controller 40 is stopped in the idle mode, and thus the gate driver 20 and the data driver 30 are also stopped. That is, in the touch screen device according to the embodiment of the present invention, power consumption can be reduced because the gate driver 20, the data driver 30, and the timing controller 40 are idle in the idle mode.

The touch driver 50 receives the mode signal MODE from the timing controller 40, receives the touch control signal TCS from the touch coordinate calculation unit 60, and receives the common voltage Vcom from a power supply source (not shown). ) is entered.

In particular, the touch driver 50 supplies the touch driving voltages VD1 to VDp to the touch electrodes 120 during the touch sensing period TP of the normal mode, and senses the touch electrodes 12 to obtain touch raw data. is transmitted to the touch coordinate calculator 60.

In addition, the touch driver 50 supplies the first touch driving voltages VDA1 to VDAp and the second touch driving voltages VDB1 to VDBp to the respective touch electrodes 120 during the touch sensing period TP of the idle mode. , Using the first touch row data due to the first touch driving voltages (VDA1 to VDAp) and the second touch row data due to the second touch driving voltages (VDB1 to VDBp), the presence or absence of a touch is determined and the result is calculated as touch coordinates forwarded to section 60.

Specifically, the touch driver 50 operates by dividing one frame period into a display driving period DP and a touch sensing period TP as shown in FIG. 5 according to the mode signal MODE in the normal mode. When the mode signal MODE of the first logic level is input, the touch driver 50 supplies the common voltage Vcom to the touch driving lines C1 to Cp during the display driving period DP as shown in FIG. 5 . When the mode signal MODE of the second logic level is input, the touch driver 50 generates touch driving voltages VD1 to VDp according to the touch control signal TCS during the touch sensing period TP, as shown in FIG. 5 . Similarly, the touch driving lines C1 to Cp may be supplied in a predetermined order. The predetermined order may be a sequential order as shown in FIG. 5 .

In FIG. 5 , it has been mainly described that the touch driving voltages VD1 to VDp have higher level voltages than the common voltage Vcom, but it is not limited thereto. Each of the touch driving voltages VD1 to VDp may include a plurality of pulses as shown in FIG. 5 . The touch driver 50 converts the sensing signals from the touch electrodes 12 into touch raw data TRD and outputs the converted touch coordinate calculator 60 .

Meanwhile, in the idle mode, the touch driver 50 may operate by dividing one frame period into a blank period BP and a touch sensing period TP, as shown in FIG. 6 . The touch driver 50 does not supply any signal or voltage to the touch driving lines C1 to Cp during the blank period BP of the idle mode. That is, the touch driver 50 is idle during the blank period BP, and as a result, the touch drive lines C1 to Cp are floating. The touch driver 50 applies the first touch driving voltages VDA1 to VDAp and the second touch driving voltages VDB1 to VDBp to the touch driving lines C1 to Cp in a predetermined order during the touch sensing period TP of the idle mode. ) to supply The predetermined order may be a sequential order as shown in FIG. 6 . In this case, the first touch driving voltages VDA1 to VDAp and the second touch driving voltages VDB1 to VDBp may include a plurality of pulses, as shown in FIG. 6 .

The touch driver 50 calculates an output voltage by sensing the voltage charged in the touch electrodes 12 during the touch sensing period TP of the normal mode and the idle mode, and converts the calculated output voltage into touch raw data. For example, the touch driver 50 calculates an output voltage by sensing the voltage charged in the capacitance of the touch electrode 12 during the touch sensing period TP of the normal mode, and converts the output voltage into touch raw data, which is digital data. (TRD). Alternatively, the touch driver 50 may sense the RC delay of the touch electrode 12 and convert the RC delay into touch raw data TRD, which is digital data.

Hereinafter, a touch driver according to an embodiment of the present invention will be described in more detail with reference to FIGS. 7 to 12 .

7 is a block diagram showing the configuration of a touch driver according to an embodiment in more detail, and FIG. 8 is a touch voltage sensing unit connected to a qth touch driving line connected to a qth touch electrode among touch electrodes. It is a block diagram showing the configuration, and FIG. 9 is a block diagram showing the configuration of the touch presence determination unit. 10 is a diagram showing a channel selection signal generated by a control signal generator, and FIG. 11 is a diagram showing a sensing operation of a touch voltage sensing unit. 12 and 13 are diagrams showing data stored in a first buffer and a second buffer according to another embodiment of the present invention, and FIG. 14 schematically shows a method of determining the presence or absence of a touch according to an embodiment of the present invention. it is a drawing

First, as shown in FIG. 7 , the touch driver 50 according to an embodiment of the present invention includes a control signal generator 80, a plurality of touch voltage sensing units 90, a multiplexer 100, and an analog-to-digital conversion unit. 110 , a first buffer 120 , a second buffer 125 , a touch detection unit 130 , and an interface unit 130 .

The control signal generation unit 80 generates a control signal for controlling the touch driver 50 according to the touch control signal TSS transmitted from the touch coordinate calculator 60 through the interface unit 130 . More specifically, the control signal generator 80 generates the channel selection signal MC as shown in FIG. 10 (a) during the touch sensing period TP in the normal mode, and the generated channel selection signal MC is delivered to the multiplexer 100.

As can be seen in FIG. 10 (a), during the touch sensing period (TP) of the normal mode, the output voltage of each touch sensing voltage unit 90 corresponding to the channel selected by the channel selection signal MC is applied to the analog-to-digital conversion unit. (110) is output. For example, while the pulse of the first channel selection signal M1 is at a high level, the output voltage of the first touch voltage sensing unit 90 corresponding to the first channel is output to the analog-to-digital conversion unit 110, and the p-th The output voltage of the p-th touch voltage sensing unit 90 corresponding to the p-th channel is output to the analog-to-digital converter 110 while the pulse of the channel selection signal Mp is at a high level.

Meanwhile, the control signal generating unit 80 generates the channel selection signal MC as shown in FIG. 10(b) during the touch sensing period TP in the idle mode, and converts the generated channel selection signal MC to a multiplexer. 100, and the output voltage of each touch sensing voltage unit 90 corresponding to the channel selected by the channel selection signal MC is output to the analog-to-digital conversion unit 110.

As can be seen in FIG. 10(b), each channel selection signal MC generated during the touch sensing period TP of the idle mode is different from the channel selection signal MC generated during the touch sensing period TP of the normal mode. Contains 2 pulses. For example, while the first pulse of the first channel selection signal M1 is maintained, the first output voltage of the first touch voltage sensing unit 90 corresponding to the first channel is output to the analog-to-digital converter 110. , the second output voltage of the first touch voltage sensing unit 90 is output to the analog-to-digital conversion unit 110 for a time during which the second pulse of the first channel selection signal M1 is maintained.

As another example, while the first pulse of the p-th channel selection signal Mp is maintained, the first output voltage of the p-th touch voltage sensing unit 90 corresponding to the p-th channel is transmitted to the analog-to-digital conversion unit 110. and the second output voltage of the p-th touch voltage sensing unit 90 is output to the analog-to-digital conversion unit 110 while the second pulse of the p-th channel selection signal Mp is maintained.

As such, the control signal generating unit 80 according to the present invention generates a channel selection signal MC including two pulses during the touch sensing period TP of the idle mode, so that each channel selection signal MC The touch voltage sensing unit 90 corresponding to the selected channel senses each touch electrode twice during the touch sensing period TP of the idle mode to output an output voltage.

Meanwhile, as shown in FIG. 11(a), the control signal generating unit 80 has a reset signal RCS for resetting the output voltage of each touch voltage sensing unit 90 in the normal mode touch sensing period TP. ) may be generated and transmitted to the touch voltage sensing unit 90 . According to the reset signal RCS, each touch voltage sensing unit 90 may reset the output voltage of each touch voltage sensing unit 90 for a predetermined time immediately before applying the touch driving voltage to the touch electrode 12. .

In addition, as shown in FIG. 11(b), the control signal generating unit 90 generates a reset signal RCS for resetting the output voltage of each touch voltage sensing unit 90 during the touch sensing period TP of the idle mode. ) may be generated and transmitted to the touch voltage sensing unit 90 . At this time, the reset signal RCS is applied to each touch voltage sensing unit for a predetermined time right before the first touch driving voltage VDA1 is applied to the touch electrode 12 and for a predetermined time right before the second touch driving voltage VDB1 is applied. The output voltage of (90) can be reset.

In one embodiment, in generating the channel selection signal MC during the touch sensing period TP of the idle mode, the control signal generating unit 90 generates a first pulse and a second pulse of the channel selection signal MC. The channel selection signal MC may be generated so that the rising edge is synchronized with the falling edge of the reset signal RCS.

The plurality of touch voltage sensing units 90 are for sensing the touch of each touch electrode 12, and are connected for each touch driving line connected to each touch electrode 12 to sense the touch of each touch electrode 12. Each touch voltage sensing unit 90 senses the touch of the touch electrode 12 and provides the output voltage Vout calculated by sensing the touch to the analog-to-digital converter 110 through the multiplexer 100 .

Hereinafter, the configuration of the touch voltage sensing unit 90 will be described in more detail with reference to FIG. 8 .

FIG. 8 shows the configuration of the touch voltage sensing unit 90 connected to the qth touch driving line Cq connected to the qth touch electrode (where q is a positive integer satisfying 1≤q≤p) among a plurality of touch electrodes. is shown

The touch voltage sensing unit 90 connects the touch electrode TEq through the qth touch driving line Cq during the touch sensing period TP of the normal mode and the touch sensing period TP of the idle mode to the touch electrode TEq. ) of the parasitic capacitance (Cp) and the capacitance (Cf) of the charged voltage (Va) is sensed.

More specifically, the touch voltage sensing unit 90 connects to the touch electrode TEq through the qth touch driving line Cq during the touch sensing period TP of the normal mode, and uses the touch electrode TEq to generate the touch driving voltage ( VDq) is supplied, and the output voltage (Vout) is calculated by sensing the voltage (Va) charged in the parasitic capacitance (Cp) and the capacitance (Cf) of the touch electrode (TEq) due to the supply of the touch driving voltage (VDq). do. The touch voltage sensing unit 90 outputs the calculated output voltage to the analog-to-digital converter 110 through the multiplexer 110 while the pulse of the qth channel selection signal Mq is maintained at a high level.

Meanwhile, the touch voltage sensing unit 90 connects to the touch electrode TEq through the qth touch driving line Cq during the touch sensing period TP of the idle mode, and uses the touch electrode TEq to generate the first touch driving voltage ( VDAq) is supplied, and the voltage Va charged in the parasitic capacitance Cp and capacitance Cf of the touch electrode TEq is sensed due to the supply of the first touch driving voltage VDAq, and the first output voltage (VDAq) is sensed. VoutA1) is calculated. The touch voltage sensing unit 90 outputs the calculated first output voltage VoutA1 to the analog-to-digital converter 110 through the multiplexer 110 while the first pulse of the qth channel selection signal Mq is maintained. do.

In addition, when the first output voltage VoutA1 is reset by the reset signal RCS, the touch voltage sensing unit 90 supplies the second touch driving voltage VDBq to the touch electrode TEq through the qth touch driving line Cq. ) is supplied, and the second output voltage VoutB1 is sensed by sensing the voltage Va charged in the parasitic capacitance Cp and capacitance Cf of the touch electrode TEq due to the supply of the second touch driving voltage VDBq. ) is calculated. The touch voltage sensing unit 90 outputs the calculated second output voltage VoutB1 to the analog-to-digital conversion unit 110 through the multiplexer 110 while the second pulse of the q th channel selection signal Mq is maintained. do.

To this end, as shown in FIG. 8 , the touch voltage sensing unit 90 includes a touch driving voltage output unit 140 , an operational amplifier 150 , a feedback capacitor 160 , and a reset switch 170 .

The touch driving voltage output unit 140 is connected to the touch driving line Cq during the normal mode touch sensing period TP and the idle mode touch sensing period TP, and outputs the touch driving voltage VDq to the touch electrode TEq. output to

Specifically, as shown in FIG. 11(a) , the touch driving voltage output unit 140 touches the touch electrode TEq through the qth touch driving line Cq during the touch sensing period TP of the normal mode. A driving voltage (VDq) is supplied. Also, as shown in FIG. 11(b) , the touch driving voltage output unit 140 provides a first contact to the touch electrode TEq through the qth touch driving line Cq during the touch sensing period TP of the idle mode. The touch driving voltage VDAq and the second touch driving voltage VDBq are supplied.

The touch electrode TEq is connected to the qth touch driving line Cq. In FIG. 8 , reference numeral “Rq” denotes resistance of the qth touch driving line Cq. As shown in FIG. 3 , the touch electrode TEq may overlap not only the pixels P, but also gate lines, data lines, or other touch driving lines. Parasitic capacitance (Cp) may be formed between the pixel electrodes and gate lines, data lines, or other touch driving lines as shown in FIG. 8 . In addition, capacitance Cs may be formed between the touch electrode TEq and a person's finger or pen, as shown in FIG. 8 . Parasitic capacitance Cp and capacitance Cs are formed in the touched touch electrode TEq, but only parasitic capacitance Cp is formed in the non-touched touch electrode. In FIG. 8 , only the touch electrode TEq where a touch is generated is illustrated for convenience of explanation.

The operational amplifier 150 includes a first input terminal IN1, a second input terminal IN2, and an output terminal o. The first input terminal IN1 of the operational amplifier 150 is connected to the qth touch driving line Cq, the second input terminal IN2 is connected to the initialization voltage line VREFL to which an initialization voltage is supplied, and outputs Terminal (o) is connected to the analog-to-digital converter 110.

At this time, although not shown in FIG. 8 , a storage capacitor Cs may be further included between the output terminal o and the analog-to-digital converter 110 . The storage capacitor Cs is connected between the output terminal o and the ground voltage source to charge the output voltage Vout of the output terminal o.

The feedback capacitor (Cfb, 160) is connected between the first input terminal (IN1) and the output terminal (o) of the operational amplifier (150).

The reset switch 170 resets the feedback capacitor 160 according to the reset signal RCS received from the control signal generator 80 during the touch sensing period TP of the normal mode and the touch sensing period TP of the idle mode. let it In particular, the reset switch 170 according to the present invention additionally resets the feedback capacitor 170 according to the sub-reset signal SRCS received from the control signal generator 80 during the touch sensing period TP of the idle mode. .

According to the operations of the operational amplifier 150, the feedback capacitor 160, and the reset switch 170, during the normal mode touch sensing period TP and the idle mode touch sensing period TP, as shown in Equation 1 below: An output voltage Vout is output from the touch sensing voltage unit 90 .

[Equation 1]

Vout=((Cs+Cp)/Cfb)*Vt

In Equation 1, "Vout" represents the output voltage of the operational amplifier 150, "Cs" represents the capacitance of the touch electrode TEq, "Cp" represents the parasitic capacitance of the touch electrode TEq, “Cfb” represents the capacitance of the feedback capacitor 160, and “Vt” represents the voltage charged in the parasitic capacitance Cp and capacitance Cs of the touch electrode TEq.

The multiplexer 100 (Multiplex: MUX) controls the output voltage Vout output from any one of the plurality of touch voltage sensing units 90 in response to the channel selection signal MC transmitted from the control signal generator 80. It is output to the analog-to-digital conversion unit 110.

In particular, the multiplexer 100 according to the present invention generates a first output voltage VoutAn calculated by applying the first touch driving voltage VDAn to each touch voltage sensing unit 90 during the touch sensing period TP of the idle mode. And the second output voltage VoutBn calculated by the application of the second touch driving voltage VDBn is transferred to the analog-to-digital conversion unit 110 . At this time, the multiplexer 100 outputs the first output voltage VoutAn to the analog-to-digital conversion unit 110 for a time during which the first pulse included in the channel selection signal MC is maintained, and outputs the first output voltage VoutAn to the channel selection signal MC. The second output voltage VoutBn is output to the analog-to-digital conversion unit 110 for a time during which the included second pulse is maintained.

The analog-to-digital conversion unit 110 (ADC) converts the output voltage Vout output from each touch voltage sensing unit 62 output from the multiplexer 100 into digital touch row data TRD1 to TRDn.

Specifically, the analog-to-digital conversion unit 110 converts the output voltage Vout calculated during the touch sensing period TP of the normal mode into touch raw data TRD, which is digital data, and stores it in the first buffer 120. . The touch raw data stored in the first buffer 120 is copied and stored in the second buffer 125 . The reason for copying and storing the touch row data stored in the first buffer 120 in the second buffer 125 is that the touch row data stored in the first buffer 125 is transmitted to the touch coordinate calculation unit 60. This is because the first buffer 125 can be reset.

The analog-to-digital conversion unit 110 converts the first output voltage VoutA calculated by the application of the first touch driving voltage VDA during the touch sensing period TP of the idle mode into first touch raw data TRDA, which is digital data. ) and stored in the first buffer 120. Also, the analog-to-digital conversion unit 110 converts the second output voltage VoutB calculated by applying the second touch driving voltage VDB during the touch sensing period TP of the idle mode to second touch raw data, which is digital data. (TRDB) and stored in the second buffer 125.

As described above, according to the present invention, the analog-to-digital conversion unit 110 generates the first touch raw data TRDA generated by the application of the first touch driving voltage VDA during the touch sensing period in the idle mode for touch sensing in the normal mode. Stored in the first buffer 120 used for updating the touch raw data acquired during the period, and generated by the application of the second touch driving voltage VDB, the second touch row data TRDB is a normal mode touch Since the touch raw data acquired during the sensing period is stored in the second buffer 125 used for holding, an additional value is required to calculate a difference between the first touch raw data TRDA and the second touch raw data TRDB. Since no frame memory or buffer is required, the size of the touch driver 50 can be minimized.

The touch presence determination unit 130 determines whether there is a touch by using the first touch raw data TRDA stored in the first buffer 120 and the second touch raw data TRDB stored in the second buffer 125 . Hereinafter, with reference to FIG. 9 , the touch presence/absence determination unit 130 according to the present invention will be described in more detail.

As shown in FIG. 9 , the touch presence determination unit 130 includes a subtractor 900 , a comparator 910 , a counter 920 , and a determination unit 930 .

First, the subtractor 900 reads first touch row data TRDA from the first buffer 120 and reads second touch row data TRDB from the second buffer 125 . Thereafter, the subtractor 900 calculates a difference between the first touch row data TRDA and the second touch row data TRDB recorded at the same address in the first buffer 120 and the second buffer 125. yields The subtractor 900 transfers the calculated difference value to the comparator 910 . In one embodiment, the subtracter 900 resets the first buffer 120 and the second buffer 125 when the calculation of the difference between the first touch row data TRDA and the second touch row data TRDB is completed. can make it

The comparator 910 compares the difference value transmitted from the subtractor 900 with a predetermined touch threshold, and determines whether the difference value exceeds the touch threshold. As a result of the determination, as shown in FIG. 14(a), when it is determined that the difference value exceeds the touch threshold, the comparator 910 transfers the determination result to the counter 920.

The counter 920 increases the number of occurrences (Repeat Tiem) of difference values exceeding the touch threshold value when a determination result that the difference value exceeds the touch threshold value is received from the comparator 910 .

As shown in FIG. 14(b) , the determination unit 930 determines that a touch has occurred when the value counted by the counter 920 exceeds a predetermined frequency, and generates information on the presence or absence of the touch to interface the interface. forwarded to unit 140.

As described above, in the present invention, after the touch driver 50 senses one touch electrode 12 twice during the touch sensing period of the idle mode to calculate first touch raw data and second touch raw data, Since the presence or absence of a touch is determined based on the difference between the 1st touch row data and the 2nd touch row data, the presence or absence of a touch can be accurately determined by removing the baseline deviation existing in the touch screen device.

Referring back to FIG. 7 , the interface unit 140 receives the touch control signal TSS from the touch coordinate calculator 60 and transfers it to the control signal generator 80 . The interface unit 140 transfers the touch row data TRD stored in the second buffer 125 to the touch coordinate calculator 60 during the touch sensing period TP of the normal mode.

In addition, the interface unit 140 transfers the touch presence information generated by the touch presence determination unit 130 to the touch coordinate calculator 60 during the touch sensing period TP of the idle mode.

Referring back to FIG. 2 , the touch coordinate calculator 60 receives touch raw data TRD from the touch driver 50 in the normal mode. The touch coordinate calculation unit 60 determines that a user's touch has occurred when the touch raw data TRD equal to or greater than the first reference value is input, and calculates the coordinates of the touch electrodes 12 of the touch raw data TRD equal to or greater than the first reference value. It is calculated by touch coordinates. The touch coordinate calculator 60 outputs touch coordinate data CD including touch coordinate information to the main processor 70 .

In addition, the touch coordinate calculating unit 60 receives information on whether or not a touch has been touched from the touch driver 50 in the idle mode, and outputs a wakeup signal WS to the main processor 70 when it is determined that a touch has occurred. .

The main processor 70 is a central processing unit (CPU) of any one of a navigation system, a set-top box, a DVD player, a Blu-ray player, a personal computer (PC), a laptop computer, a home theater system, a broadcasting receiver, a smartphone, a tablet, and a mobile terminal. ), a host processor, an application processor, or a graphics processing unit (GPU).

The main processor 70 outputs the idle mode control signal IMS of the first logic level to the timing controller 40 in the normal mode. The main processor 70 converts the digital video data DATA into a format suitable for display on the display panel 10 in the normal mode and transmits it to the timing controller 40 . The main processor 70 may receive touch coordinate data CD from the touch coordinate calculator 60 . The main processor 70 executes an application program or an application program of an icon existing at the touch coordinates according to the touch coordinate data CD in normal mode, and generates digital video data DATA and timing signals TS according to the execution program. is transmitted to the timing controller 40.

When the main process 70 changes from the normal mode to the idle mode, the main process 70 transfers the idle mode control signal IMS of the second logic level to the timing controller 40 and is stopped. The main processor 70 wakes up when the wakeup signal WS is input from the touch coordinate calculation unit 70 in the idle mode. When the main processor 70 wakes up, it operates in normal mode.

As described above, in the embodiment of the present invention, the gate driving unit 20, the data driving unit 30, the timing controlling unit 40, and the main processor 70 are idle in the idle mode, and the touch driving unit 50 and the touch Only the coordinate calculation unit 60 is operated to sense the user's touch. As a result, the embodiment of the present invention can sense a user's touch in idle mode with minimal power consumption. Due to this, the embodiment of the present invention can wake up the touch screen device from the idle mode when a touch of a predetermined pattern is input on the touch screen device.

Modified Embodiments

First modified embodiment

In the above-described embodiment, the touch driver 50 senses each touch electrode 12 twice during the touch sensing period TP of the idle mode, and uses the first touch row data and the second touch row data obtained by sensing each touch electrode 12 twice. It was described as determining the presence or absence of touch.

However, in a modified embodiment, the touch driver 50 may sense each touch electrode only once during the touch sensing period TP of the idle mode, similarly to the touch sensing period TP of the normal mode.

According to this embodiment, the analog-to-digital conversion unit 110 obtains the touch voltage by sensing the touch electrodes 12 connected to each touch voltage sensing unit 90 during the touch sensing period TP of the idle mode in the nth frame. The output voltages are digitally converted to generate touch row data TRD, and as shown in FIG. 12, among the touch row data TRD generated for each touch voltage sensing unit 90, the order of magnitude of the values According to , n touch row data (eg, max TRD and 2 ^nd max TRD in FIG. 12 ) are selected from the top and stored in the first buffer 120 .

In addition, the analog-to-digital conversion unit 110 outputs all outputs obtained by sensing the touch electrodes 12 connected to each touch voltage sensing unit 90 during the touch sensing period TP of the idle mode in the n+1th frame. Voltages are converted to digital to generate touch row data TRD, and as shown in FIG. 12(b), the size of the value among the touch row data TRD generated for each touch voltage sensing unit 90 In order, n touch row data (eg, max TRD and 2 ^nd max TRD in FIG. 12 ) are selected and stored in the second buffer 125 .

Thereafter, the touch presence determination unit 130 having the same configuration as shown in FIG. 9 reads the touch row data recorded in the same address in the first buffer 120 and the second buffer 125 to calculate a difference value When the number of times the calculated difference value exceeds the touch threshold exceeds a predetermined frequency, it is determined that a touch has occurred.

Second modified embodiment

In another embodiment, when the touch driver 50 senses each touch electrode once during the touch sensing period TP of the idle mode, the analog-to-digital converter 110 performs touch sensing in the idle mode in the nth frame. During the period TP, the output voltages obtained by sensing the touch electrodes 12 connected to each touch voltage sensing unit 90 are digitally converted to generate touch row data TRD, as shown in FIG. 13. As shown above, among the touch row data TRD generated for each touch voltage sensing unit 90, the touch row data max TRD having the maximum value and the touch voltage outputting the output voltage corresponding to the touch row data having the maximum value are output. The identification information (max ID) of the sensing unit 90 is stored in the first buffer 120 .

In addition, the analog-to-digital conversion unit 110 outputs all outputs obtained by sensing the touch electrodes 12 connected to each touch voltage sensing unit 90 during the touch sensing period TP of the idle mode in the n+1th frame. Voltages are converted to digital to generate touch row data TRD, and as shown in FIG. The touch row data (max TRD) and the identification information (max ID) of the touch voltage sensing unit 90 outputting the output voltage corresponding to the touch row data having the maximum value are stored in the second buffer 125.

Thereafter, the touch presence determination unit 130 having the same configuration as shown in FIG. 9 reads the touch row data recorded in the same address in the first buffer 120 and the second buffer 125 to calculate a difference value When the number of times the calculated difference value exceeds the touch threshold exceeds a predetermined frequency, it is determined that a touch has occurred.

According to this embodiment, since the identification information of the touch voltage sensing unit 90 that outputs the output voltage corresponding to the touch raw data having the maximum value is also recorded, a touch electrode connected to a certain touch voltage sensing unit 90 ( In 12), it is also possible to check whether or not a touch has occurred.

Third modified embodiment

In another embodiment, when the touch driver 50 senses each touch electrode once during the touch sensing period TP of the idle mode, the analog-to-digital converter 110 performs touch sensing in the idle mode in the nth frame. During the period TP, output voltages obtained by sensing the touch electrodes 12 connected to each touch voltage sensing unit 90 are digitally converted to generate touch raw data TRD, and each touch voltage sensing unit (90) The touch row data having the maximum value among the touch row data TRD generated for each touch row data and the average value of the touch row data generated for each touch voltage sensing unit 90 are stored in the first buffer 120.

In addition, the analog-to-digital conversion unit 110 outputs all outputs obtained by sensing the touch electrodes 12 connected to each touch voltage sensing unit 90 during the touch sensing period TP of the idle mode in the n+1th frame. Voltages are converted to digital to generate touch row data TRD, and among the touch row data TRD generated for each touch voltage sensing unit 90, the touch raw data having the maximum value and each touch voltage sensing unit ( 90) and stores the average value of touch row data generated for each stage in the second buffer 125.

Thereafter, the touch presence determination unit 130 having the same configuration as shown in FIG. 9 determines the touch row data (or average values) recorded at the same address in the first buffer 120 and the second buffer 125. A difference value is calculated by reading, and when the number of times the calculated difference value exceeds the touch threshold exceeds a predetermined frequency, it is determined that a touch has occurred.

4th modified embodiment

In the above-described embodiment, it has been described that the touch presence/absence determination unit 130 for determining the presence of a touch is included in the touch driver 50 . However, in a modified embodiment, the touch presence determining unit 130 may be included in the touch coordinate calculating unit 60 . According to this embodiment, the interface unit 140 reads the touch row data stored in the first buffer 120 and the touch row data stored in the second buffer 125, and the touch coordinate calculator 60 will be forwarded to Thereafter, the touch presence determination unit 130 included in the touch coordinate calculation unit 60 uses the touch row data stored in the first buffer 120 and the touch row data stored in the second buffer 125 to determine It determines whether or not there is a touch.

Hereinafter, a touch driving method of a touch screen device according to the present invention will be described in more detail with reference to FIGS. 15A and 15B.

15A and 15B are flowcharts illustrating a touch driving method of a touch screen device according to an embodiment of the present invention.

The touch driving method of the touch screen shown in FIGS. 15A and 15B may be applied to a touch screen device having a configuration as shown in FIG. 2 .

As shown in FIGS. 15A and 15B , the touch screen device determines whether the driving mode is a normal mode or an idle mode according to the logic level of the idle mode control signal (IMS) (S1400).

As a result of the determination in S1400, if it is determined that the driving mode is the idle mode, the touch screen device sequentially supplies a first touch driving voltage and a second touch driving voltage to each touch electrode 12 (S1410), and then first touch driving A first output voltage is calculated by sensing the voltage charged in the touch electrode 12 by the voltage, and a second output voltage is calculated by sensing the voltage charged in the touch electrode 12 by the second touch driving voltage (S1420). ).

Thereafter, the touch screen device generates first touch row data by converting the first output voltage to digital, and generates second touch row data by converting the second output voltage to digital (S1430). At this time, the touch screen device stores the first touch row data in the first buffer 120 and the second touch row data in the second buffer 125 .

Then, the touch screen device calculates a difference between the first touch row data stored in the first buffer 120 and the second touch row data stored in the second buffer 125 (S1440).

Thereafter, the touch screen device compares the difference value calculated in S1440 with a predetermined touch threshold value to determine whether the difference value exceeds the touch threshold value (S1450). As a result of the determination, if the difference value exceeds the touch threshold value, the touch screen device increases the number of times the difference value exceeds the touch threshold value (S1460).

Thereafter, the touch screen device determines whether the number of times the difference value exceeds the touch threshold exceeds a predetermined threshold frequency (S1470), and if the number of times the difference value exceeds the touch threshold exceeds the predetermined threshold frequency (S1470). It is determined that a touch has occurred (S1480). Thereafter, the touch screen device wakes up by generating a wakeup signal and operates in a normal mode. Accordingly, the idle mode ends (S1490).

Meanwhile, when it is determined that the driving mode is the normal mode as a result of the determination in S1400, the touch screen device supplies a touch driving voltage to each touch electrode 12 (S1500), and then charges the touch electrodes 12 by the touch driving voltage. The output voltage is calculated by sensing the detected voltage (1510).

Then, the touch screen device 50 converts the output voltage into digital to generate touch row data (S1520), and determines whether the generated touch row data exceeds a first reference value (S1530). As a result of the determination, if the touch raw data exceeds the first reference value, the touch screen device determines that a touch has occurred and calculates touch coordinates (S1540).

Meanwhile, although not shown in FIG. 15 , a step of generating a channel selection signal for sequentially outputting the first output voltage and the second output voltage calculated for each touch electrode may be further included.

This channel selection signal includes a first pulse for outputting a first output voltage and a second pulse for outputting a second output voltage.

According to this embodiment, the first touch driving voltage is supplied to the touch electrode in S1410 while the first pulse is maintained, and the first output voltage is calculated in S1420. Also, while the second pulse is maintained, the second touch driving voltage is supplied to the touch electrode in S1410 and the second output voltage is calculated in S1420.

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

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 following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention. do.

10: display panel 20: gate driver
30: data driver 40: timing controller
50: touch drive unit 60: touch coordinate calculation unit
70: main processor 80: control signal generator
90: touch voltage sensing unit 100: multiplexer
110: analog-to-digital converter 120: first buffer
125: second buffer 130: touch presence determining unit
140: interface unit

Claims (9)

a display panel including touch electrodes serving as common electrodes;
A blank period during idle mode driving and a first touch sensing period for driving and sensing the touch electrodes alternate, and a display driving period for supplying a common voltage to the touch electrodes during normal mode driving and a touch driver that alternates second touch sensing periods for driving and sensing the touch electrodes;
the touch driver,
a plurality of touch voltage sensing units configured to sense a voltage charged in each of the touch electrodes twice during the first touch sensing period of the idle mode to calculate a first output voltage and a second output voltage;
The first output voltage output from each touch voltage sensing unit is digitally converted to generate first touch row data, and the second output voltage output from each touch voltage sensing unit is digitally converted to generate second touch row data. an analog-to-digital conversion unit that generates;
a multiplexer sequentially connecting the plurality of touch voltage sensing units to the analog-to-digital conversion unit;
a control signal generation unit generating a channel selection signal for connecting each of the touch voltage sensing units to the analog-to-digital conversion unit and supplying the generated channel selection signal to the multiplexer; and
a touch determination unit configured to determine whether or not there is a touch based on the first touch raw data and the second touch raw data;
Each of the plurality of touch voltage sensing units,
During the first touch sensing period in the idle mode, a pair of first and second driving pulse patterns are continuously supplied to each touch electrode, and before the other touch electrode is driven, the voltage charged in each touch electrode is reduced to 2 Continuously calculating the first and second output voltages by sensing them three times in succession;
During the second touch sensing period in the normal mode, a third driving pulse pattern is supplied to each touch electrode and a voltage charged in each touch electrode is sensed to calculate a third output voltage;
The control signal generating unit,
During the first touch sensing period of the idle mode, when the multiplexer selects each touch voltage sensing unit connected to the analog-to-digital conversion unit, a pair of first and second pulses are continuously supplied as the channel selection signal;
During the second touch sensing period of the normal mode, when the multiplexer selects each touch voltage sensing unit connected to the analog-to-digital conversion unit, a third pulse is supplied as the channel selection signal. According to claim 1,
the touch driver
a first buffer storing touch raw data obtained during the second touch sensing period of the normal mode and storing the first touch raw data during the first touch sensing period of the idle mode; and
a second buffer in which touch row data stored in the first buffer is copied and stored during the second touch sensing period in the normal mode and in which the second touch row data is stored in the first touch sensing period in the idle mode; A touch screen device further comprising. According to claim 1,
a gate driver, data driver, and timing controller for driving the display panel during the display driving period in the normal mode;
a main processor outputting an idle mode control signal to the timing controller and the touch driver;
When the idle mode control signal is at a first logic level, the main processor, the gate driver, the data driver, the timing controller, and the touch driver operate in the normal mode in which the display driving period and the second touch sensing period alternate. driven by
When the idle mode control signal is at a second logic level, the main processor, the gate driver, the data driver, and the timing controller are idle, and only the touch driver is driven in the idle mode. According to claim 1,
The touch determination unit,
a subtractor calculating a difference between the first touch row data and the second touch row data;
a comparator comparing the difference value with a predetermined touch threshold value and determining whether the difference value exceeds the touch threshold value;
a counter counting the number of occurrences of a difference value exceeding the touch threshold; and
and a determination unit determining that a touch has occurred when the value counted by the counter exceeds a predetermined threshold frequency. According to claim 1,
During the first touch sensing period of the idle mode,
The channel selection signal,
The first pulse for outputting the first output voltage to the analog-to-digital converter and the second pulse for outputting the second output voltage to the analog-to-digital converter;
Each of the touch voltage sensing units,
The first output voltage is calculated and outputted to the analog-to-digital converter while the first pulse of the channel selection signal is maintained, and the second output voltage is calculated while the second pulse of the channel selection signal is maintained. The touch screen device characterized in that the output to the analog-to-digital conversion unit. delete delete delete delete

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