KR102527732B1 - Touch circuit, touch display device, and driving method thereof - Google Patents

Abstract

Embodiments of the present invention relate to a touch circuit, a touch display device, and a method for driving the same, and more particularly, a first circuit connected between a sensing unit and a touch channel connected to a touch screen panel and a first input terminal of the sensing unit. A switching element, a second switching element connected to the touch channel and the second input terminal of the sensing unit, and a discharge switch connected between the touch channel and the ground and controlled independently of the first switching element and the second switching element. By including the present invention, it is possible to provide a touch circuit, a touch display device, and a method for driving the same that prevent blur caused by noise flowing into a touch screen panel.

Description

Touch circuit, touch display device and its driving method {TOUCH CIRCUIT, TOUCH DISPLAY DEVICE, AND DRIVING METHOD THEREOF}

Embodiments of the present invention relate to a touch circuit, a touch display device, and a method for driving the same.

As the information society develops, the demand for display devices for displaying images is increasing in various forms, and recently, liquid crystal display devices (LCD: Liquid Crystal Display Device), plasma display devices (PDP: Plasma Display Panel), organic Various display devices such as organic light emitting display devices (OLEDs) have been utilized.

Such a display device provides a touch-based input method that allows a user to easily and intuitively and conveniently input information or commands, breaking away from conventional input methods such as buttons, keyboards, and mice.

In order to provide such a touch-based input method, it is necessary to determine whether or not a user has touched and accurately detect touch coordinates.

To this end, the presence or absence of touch is determined based on a change in capacitance between touch electrodes or between a touch electrode and a pointer such as a finger through a plurality of touch electrodes (eg, horizontal electrodes and vertical electrodes) formed in a touch display device. And a capacitance touch method for detecting touch coordinates is widely adopted.

At this time, if external noise or an abnormal signal such as a walkie-talkie signal flows into the touch sensing circuit while the touch display device is operating, an error occurs in the touch sensing circuit, resulting in a decrease in accuracy of touch sensing or a specific block of the touch display panel. The problem of blurring (block dim) appears.

Embodiments of the present invention may provide a touch circuit, a touch display device, and a method for driving the touch circuit that prevent blur caused by noise.

In addition, embodiments of the present invention may provide a touch circuit that discharges noise flowing into a touch screen panel, a touch display device, and a method for driving the same.

Further, embodiments of the present invention may provide a touch circuit capable of detecting and discharging noise when noise is introduced into a touch screen panel, a touch display device, and a driving method thereof.

In one aspect, embodiments of the present invention provide a sensing unit, a first switching element connected between a touch channel connected to a touch screen panel and a first input terminal of the sensing unit, and a second input terminal of the touch channel and the sensing unit. A touch circuit may include a second switching element connected thereto, and a discharge switch connected between the touch channel and the ground and controlled independently of the first switching element and the second switching element.

On the other hand, embodiments of the present invention provide a display panel on which a plurality of data lines and a plurality of gate lines are disposed and a plurality of subpixels, a data driving circuit for driving the plurality of data lines, and a plurality of gate lines. Provided is a touch display device including a gate driving circuit for driving, a timing controller for controlling the data driving circuit and the gate driving circuit, and a touch circuit for sensing a touch by sequentially driving a plurality of common electrodes constituting a display panel. The touch circuit may include a first switching element connected between the sensing unit and the touch channel connected to the display panel and the first input terminal of the sensing unit, and a second switching device connected to the touch channel and the second input terminal of the sensing unit. device, and a discharge switch connected between the touch channel and the ground and controlled independently of the first switching device and the second switching device.

In another aspect, embodiments of the present invention provide a sensing unit, a first switching element connected between a touch channel connected to a touch screen panel and a first input terminal of the sensing unit, and a second input terminal of the touch channel and the sensing unit. A second switching element connected therebetween, a discharge switch connected between the second input terminal of the sensing unit and the ground, and controlled independently of the first switching element and the second switching element, and a second input terminal of the sensing unit It is possible to provide a touch circuit including a switch for a common voltage connected between and the common voltage.

In another aspect, embodiments of the present invention provide a display panel on which a plurality of data lines and a plurality of gate lines are disposed and a plurality of subpixels, a data driving circuit for driving the plurality of data lines, and a plurality of gates. A touch display device including a gate driving circuit for driving a line, a timing controller for controlling the data driving circuit and the gate driving circuit, and a touch circuit for sensing a touch by sequentially driving a plurality of common electrodes constituting a display panel. The touch circuit may include a sensing unit, a first switching element connected between a touch channel connected to the touch screen panel and the first input terminal of the sensing unit, and a connection between the touch channel and the second input terminal of the sensing unit. A second switching element, a discharge switch connected between the second input terminal of the sensing unit and the ground, and controlled independently of the first switching element and the second switching element, and a common voltage with the second input terminal of the sensing unit A switch for a common voltage connected therebetween may be included.

In another aspect, embodiments of the present invention provide a display panel on which a plurality of data lines, a plurality of gate lines, and a plurality of subpixels are disposed, a data driving circuit for driving the plurality of data lines, and driving the plurality of gate lines. A method of driving a touch display device including a gate driving circuit for controlling a gate driving circuit, a timing controller for controlling the data driving circuit and the gate driving circuit, and a touch circuit for sensing a touch by sequentially driving a plurality of common electrodes constituting a display panel. Before entering the display mode or the touch mode, turning on a discharge switch connected between the touch channel of the display panel and the ground to discharge noise introduced into the display panel; A driving method comprising turning on a first switching element connected between sensing units of a touch circuit and turning on a second switching element connected between a touch channel and a sensing unit in a display mode. can do.

In another aspect, embodiments of the present invention may further include a noise detection circuit connected to the sensing unit, wherein the noise detection circuit receives an analog-to-digital converter connected to an output terminal of the sensing unit and an output signal of the analog-to-digital converter. A touch circuit and a touch display device including a plurality of XNOR gates receiving signals and an AND gate receiving output signals of the plurality of XNOR gates may be provided.

According to embodiments of the present invention, it is possible to provide a touch circuit, a touch display device, and a method for driving the same that prevent blur caused by noise flowing into a touch screen panel.

In addition, according to embodiments of the present invention, it is possible to provide a touch circuit, a touch display device, and a method for driving the same that prevent blur caused by noise by discharging noise introduced into a touch screen panel.

In addition, according to embodiments of the present invention, when noise is introduced into a touch screen panel, it is possible to provide a touch circuit, a touch display device, and a method for driving the same that prevent blur caused by noise by detecting and discharging the noise. .

1 is a system configuration diagram illustrating an example of a touch display device according to the present embodiments.
2 is a diagram illustrating an example of touch driving and sensing operations in the touch display device according to the present embodiments.
3 is a diagram illustrating an example of a touch screen panel embedded in a display panel of a touch display device according to the present embodiments.
4 is a diagram illustrating a connection relationship between a touch screen panel and a sensing unit in the touch display device according to the present embodiments.
5 is a diagram illustrating an example of an operation mode of a touch display device according to the present embodiments.
6 is a diagram illustrating an example of a case in which a display error occurs on a touch screen panel when a noise signal such as a radio signal is introduced into the touch display device.
7 is a diagram illustrating a signal timing diagram in which noise such as a radio signal is introduced in a touch display device.
8 and 9 are diagrams illustrating circuit operations when a display error occurs due to noise such as a radio signal.
10 is a diagram showing the configuration of a touch circuit according to an embodiment of the present invention.
11 is a diagram illustrating signal timing for discharging noise such as a radio signal in a touch display device according to an embodiment of the present invention.
12 is a diagram illustrating a circuit operation of discharging noise such as a radio signal in a touch display device according to an embodiment of the present invention.
13 is a diagram illustrating signal timing for discharging noise such as a radio signal in a touch display device according to another embodiment of the present invention.
14 is a diagram illustrating a timing diagram of a switching signal controlling a multiplexer to discharge noise such as a radio signal in a touch display device according to an embodiment of the present invention.
15 is a diagram showing the configuration of a touch circuit according to another embodiment of the present invention.
16 is a diagram showing the configuration of a touch circuit according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention are described in detail below with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted. When "comprises", "has", "consists of", etc. mentioned in this specification is used, other parts may be added unless "only" is used. In the case where a component is expressed in the singular, it may include the case of including the plural unless otherwise explicitly stated.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the corresponding component is not limited by the term.

In the description of the positional relationship of components, when it is described that two or more components are "connected", "coupled" or "connected", the two or more components are directly "connected", "coupled" or "connected". ", but it will be understood that two or more components and other components may be further "interposed" and "connected", "coupled" or "connected". Here, other components may be included in one or more of two or more components that are “connected”, “coupled” or “connected” to each other.

In the description of the temporal flow relationship related to components, operation methods, production methods, etc., for example, "after", "continued to", "after", "before", etc. Alternatively, when a flow sequence relationship is described, it may also include non-continuous cases unless “immediately” or “directly” is used.

On the other hand, when a numerical value or corresponding information (eg, level, etc.) for a component is mentioned, even if there is no separate explicit description, the numerical value or its corresponding information is not indicated by various factors (eg, process factors, internal or external shocks, noise, etc.) may be interpreted as including an error range that may occur.

1 is a system configuration diagram illustrating an example of a touch display device according to the present embodiments.

Referring to FIG. 1 , a touch display device 100 according to the present embodiments is a display device capable of providing both an image display function and a touch sensing function.

In the touch display device 100 according to the present embodiments, in order to provide an image display function, a plurality of data lines (DL) and a plurality of gate lines (GL) are disposed, and a plurality of sub a display panel 110 on which pixels (subpixels) are disposed, a data driving circuit 120 driving a plurality of data lines DL, and a gate driving circuit 130 driving a plurality of gate lines GL; A timing controller 140 controlling the data driving circuit 120 and the gate driving circuit 130 is included.

The timing controller 140 controls the data driving circuit 120 and the gate driving circuit 130 by supplying various control signals to the data driving circuit 120 and the gate driving circuit 130 .

The timing controller 140 starts scanning according to the timing implemented in each frame, converts externally input image data according to the data signal format used by the data driving circuit 120, and outputs the converted image data. and controls data driving at an appropriate time according to the scan signal.

The data driving circuit 120 drives the plurality of data lines DL by supplying data voltages to the plurality of data lines DL.

The gate driving circuit 130 sequentially drives the plurality of gate lines GL by sequentially supplying scan signals to the plurality of gate lines GL.

The gate driving circuit 130 sequentially supplies scan signals of an on voltage or an off voltage to the plurality of gate lines GL under the control of the timing controller 140 .

When a specific gate line GL is opened by the gate driving circuit 130, the data driving circuit 120 converts the image data received from the timing controller 140 into analog data voltages to form a plurality of data lines DL. supply with

Although FIG. 1 shows the case where the data driving circuit 120 is located on only one side (eg, upper or lower side) of the display panel 110, depending on the driving method or panel design method, both sides (eg, the display panel 110) Example: upper and lower) may be located on both sides.

Similarly, although FIG. 1 shows the case where the gate driving circuit 130 is located on only one side (eg, the left or right side) of the display panel 110, the display panel 110 may be located on both sides (eg, left and right) of

The aforementioned timing controller 140 includes a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input data enable (DE) signal, a clock signal (CLK), and the like, together with input image data. Receives various timing signals from the outside (eg host system).

The timing controller 140 converts image data input from the outside to suit the format of the data signal used by the data driving circuit 120 and outputs the converted image data, as well as the data driving circuit 120 and gate driving. In order to control the circuit 130, timing signals such as a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input data enable signal, and a clock signal are input, and various control signals are generated to generate the data driving circuit 120 ) and the gate driving circuit 130.

For example, the timing controller 140 controls the gate driving circuit 130 by using a gate start pulse (GSP), a gate shift clock (GSC), and a gate output enable signal (GOE). : Gate Output Enable) and various gate control signals (GCS: Gate Control Signal) are output.

Here, the gate start pulse GSP controls the start timing at which the gate driving circuit 130 operates. The gate shift clock GSC is a clock signal commonly input to the gate driving circuit 130 and controls the shift timing of the scan signal. The gate output enable signal GOE designates timing information of the gate driving circuit 130 .

In addition, the timing controller 140 controls the data driving circuit 120 by using a source start pulse (SSP), a source sampling clock (SSC), and a source output enable signal (SOE). It outputs various data control signals (DCS: Data Control Signal) including Output Enable) and the like.

Here, the source start pulse SSP controls the timing at which the data driving circuit 120 starts sampling data. The source sampling clock SSC is a clock signal that controls data sampling timing in the data driving circuit 120 . The source output enable signal SOE controls output timing of the data driving circuit 120 .

Each data drive circuit 120 is connected to a bonding pad of the display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) method, or It may be directly disposed on the panel 110 or, in some cases, may be integrated and disposed on the display panel 110 .

In addition, each data driving circuit 120 may be implemented in a chip on film (COF) method mounted on a film 121 connected to the display panel 110 .

Each data driving circuit 120 may include a shift register, a latch circuit, a digital to analog converter (DAC), an output buffer, and the like.

Each gate driving circuit 130 is connected to a bonding pad of the display panel 110 using a tape automated bonding (TAB) method or a chip on glass (COG) method, or implemented in a Gate In Panel (GIP) type. and may be directly disposed on the display panel 110 or, in some cases, may be integrated and disposed on the display panel 110 .

In addition, each gate driving circuit 130 may be implemented in a chip on film (COF) method mounted on a film 131 connected to the display panel 110 .

Each gate driving circuit 130 may include a shift register, a level shifter, and the like.

The touch display device 100 according to the present embodiments includes at least one S-PCB (Source Printed Circuit Board, 160) required for circuit connection to the data driving circuit 120, and control components. , and a control printed circuit board (C-PCB: Control Printed Circuit Board, 170) for mounting various electrical devices.

The data driving circuit 120 may be mounted on at least one source printed circuit board 160 or the film 121 on which the data driving circuit 120 is mounted may be connected.

The control printed circuit board 170 includes a timing controller 140 that controls operations of the data driving circuit 120 and the gate driving circuit 130, the display panel 110, the data driving circuit 120, and the gate driving circuit. A power control circuit 150 or the like that supplies various voltages or currents to 130 or the like or controls various voltages or currents to be supplied may be mounted.

The at least one source printed circuit board 160 and the control printed circuit board 170 may be circuitically connected through at least one connecting member 180 .

Here, the connecting member 180 may be a flexible printed circuit (FPC) or a flexible flat cable (FFC).

At least one source printed circuit board 160 and the control printed circuit board 170 may be integrated into one printed circuit board.

The touch display device 100 according to the present embodiments may be a device of various types such as a liquid crystal display device, an organic light emitting display device, and a plasma display device. can

2 is a diagram illustrating an example of touch driving and sensing operations in the touch display device according to the present embodiments.

Referring to FIG. 2 , the touch display device 100 according to the present embodiments includes a plurality of common electrodes (CE) serving as touch sensors (touch electrodes) to provide a touch sensing function, and a plurality of common electrodes (CE). and a touch circuit 190 that senses a touch by sequentially driving the common electrodes CE.

The touch circuit 190 sequentially drives and senses the plurality of common electrodes CE, detects whether or not there is a touch, and calculates touch coordinates.

More specifically, the touch circuit 190 selects at least one of the plurality of common electrodes CE as the common electrode CEs to be sensed, and supplies the touch driving signal TDS to the selected common electrode CEs. . Then, based on the touch sensing signal TSS received for each of the selected common electrodes CEs and non-selected common electrodes CEo, the amount of change in capacitance (or the amount of change in voltage or amount of charge) for each common electrode CE is determined. By recognizing, the presence or absence of a touch may be detected or touch coordinates may be calculated.

The touch circuit 190 may include, for example, a micro control unit (MCU) 192 that controls signal generation related to touch sensing, and performs processes for detecting touch presence and calculating touch coordinates, and a touch screen panel ( A touch sensing circuit that supplies the touch driving signal TDS to the TSP, detects the touch sensing signal TSS from the common electrodes CEs to which the touch driving signal TDS is supplied, and transfers it to the micro control unit 192 ( 194), etc.

3 is a diagram illustrating an example of a touch screen panel embedded in a display panel of a touch display device according to the present embodiments.

Referring to FIG. 3 , a plurality of common electrodes CE may be disposed inside the display panel 110 . That is, the display panel 110 of the touch display device 100 according to the present embodiments may be said to have a built-in touch screen panel (TSP).

The plurality of common electrodes CE embedded in the display panel 110 not only operate as touch electrodes (touch sensors) as described above, but also display to which a common voltage Vcom opposite to a pixel voltage is applied to display an image. It can also act as an electrode.

Meanwhile, supplying the touch driving signal TDS to the plurality of common electrodes CE that can operate as touch electrodes and supplying the common voltage Vcom to the plurality of common electrodes CE that can operate as display electrodes To this end, one touch channel 300 may be connected to one common electrode CE. That is, one common electrode CE may be connected to the touch circuit 190 and the common voltage supply circuit through one touch channel 300 .

The common electrodes CE include transparent electrodes made of a transparent conductive material such as indium tin oxide (ITO). Each of the transparent electrodes is formed as a transparent electrode pattern larger than the size of the subpixels so as to overlap a plurality of subpixels and supply a common voltage to the plurality of subpixels.

In the common electrode CE described in this specification, “common” means that the common electrode CE is shared as a touch electrode and a display electrode. That is, “common” means that the touch mode and the display mode are common. In addition to this meaning, “common” may mean that a “common voltage Vcom” is applied to a plurality of common electrodes CE operating as display electrodes.

As described above, the touch display device 100 according to the present embodiments may provide both an image display function and a touch sensing function. For example, it may be a display device such as a TV or a monitor, or a computer such as a laptop computer. or a mobile device such as a smart phone or a tablet.

The touch display device 100 according to the present embodiments can operate in a display mode for providing an image display function and a touch mode for providing a touch sensing function.

4 is a diagram illustrating a connection relationship between a touch screen panel (TSP) and a sensing unit (SSU) in the touch display device according to the present embodiments.

Referring to FIG. 4 , n touch channels 300 are respectively connected to n common electrodes CE formed on the touch screen panel TSP. Here, since the common electrode CE supplies the touch sensing signal TSS to the touch sensing circuit 194 through the touch channel 300 by a touch input applied to the touch screen panel TSP, the touch electrode or the touch It serves as a sensor.

The touch sensing circuit 194 including the plurality of sensing units SSU receives the touch sensing signal TSS through n touch channels 300 . That is, the n sensing units SSU are respectively connected to the n touch channels 300 and receive the self-capacitance signal as the touch sensing signal TSS.

In this case, each of the sensing units SSU may be connected to a second touch channel adjacent to the first touch channel to which it is connected. In this case, each of the sensing units SSU may differentially receive a first touch sensing signal input from a first touch channel and a second touch sensing signal input from a second touch channel. The touch sensing circuit 194 detects a change in the capacitance value of the common electrode CE and generates touch sensing output data Sout of a predetermined bit.

The sensing unit (SSU) connected to a specific touch channel consists of an OP Amp (Operational Amplifier), and is connected between the inverting input terminal (-) and the touch screen panel (TSP), and the first multiplexer (MUX_0) for touch sensing and the non-inverting It is connected between the input terminal (+) and the touch screen panel (TSP) and includes a second multiplexer (MUX_1) for applying a common voltage (Vcom), and a common voltage (Vcom) is applied to the non-inverting input terminal (+). do.

The touch sensing circuit 194 is an inverter (INV) between the first multiplexer MUX_0 connected to the inverting input terminal (-) of the sensing unit SSU and the second multiplexer MUX_1 connected to the non-inverting input terminal (+) of the sensing unit SSU. ), so that when the first multiplexer MUX_0 is turned on by the switching signal SW0, the second multiplexer MUX_1 is automatically turned off.

Therefore, the first multiplexer MUX_0 is turned on by the switching signal SW0, the touch sensing signal TSS is introduced to the inverted input terminal (-) of the sensing unit SSU, and the ratio of the sensing unit SSU When the common voltage Vcom is applied to the inverting input terminal (+), the sensing unit SSU compares the touch sensing signal TSS and the common voltage Vcom to generate touch sensing output data Sout.

Conversely, when the first multiplexer MUX_0 is turned off by the switching signal SW0 and the second multiplexer MUX_1 connected to the non-inverting input terminal (+) is turned on, the common voltage Vcom touches It will be applied to the screen panel (TSP).

The first multiplexer (MUX_0) and the second multiplexer (MUX_1) connected to the sensing unit (SSU) are composed of one group, and according to the pixel configuration of the touch screen panel (TSP), the touch screen panel (TSP) can be connected to

For example, the gate line GL of the touch screen panel TSP is divided into 10 blocks with a certain number of columns, and the first multiplexer MUX_0 and the second multiplexer MUX_1 are connected to each block. In this case, 10 groups of multiplexers MUX0 to MUX9 including the first multiplexer MUX_0 and the second multiplexer MUX_1 as one group may be connected to the touch sensing circuit 194 .

Although the first multiplexer MUX_0 and the second multiplexer MUX_1 have been described above for the purpose of sensing a touch signal of the touch screen panel TSP or applying a common voltage Vcom to the touch screen panel TSP, Since it is used for the purpose of controlling the signal direction between the screen panel (TSP) and the sensing unit (SSU), it may be expressed as a switch.

5 is a diagram illustrating an example of an operation mode of a touch display device according to the present embodiments.

Referring to FIG. 5 , the touch display device 100 according to the present embodiments has two operation modes including a display mode for providing an image display function and a touch mode for providing a touch sensing function. These operation modes may be temporally divided or overlapped in the same time interval.

For example, in Case A, the touch display device 100 may operate in a display mode or a touch mode at any point in time. In this case, the display mode and the touch mode may proceed in a time division manner, and the display mode section and the touch mode section are temporally separated.

The display mode and the touch mode may be temporally divided by the time division control signal TsyncN. For example, when the time division control signal TsyncN is at a low level (“0”), the touch mode operates, and the time division control When the signal TsyncN has a high level (“1”), the display mode may be operated. Also, the number of operations in the display mode and the touch mode can be controlled by allowing the voltage level of the time division control signal TsyncN to be changed only once or twice or more during one frame period.

When the display mode and the touch mode are temporally separated, the second multiplexer MUX_1 is turned on in the display period in which display is performed, and the common voltage Vcom is applied to the touch screen panel TSP. The multiplexer MUX_0 is turned on to apply the touch sensing signal TSS from the touch screen panel TSP to the sensing unit SSU.

On the other hand, in Case B and Case C, the touch display device 100 can operate both in the display mode and in the touch mode at the same time. In this case, the display mode and the touch mode may proceed spatially independently, and the display mode section and the touch mode section may temporally overlap.

Below, a case in which the touch display device 100 is operated by temporally dividing the display mode and the touch mode will be described as an example, but the operation of the display mode and the touch mode may be variously changed.

In the case of a currently used touch display device, when a noise signal such as a high-output radio signal (RF) or ESD (Electro-Static Discharge) flows into the touch screen panel (TSP) in the display section, this causes the touch It affects the screen panel (TSP) and causes errors in display operation as well as touch sensing.

6 is a diagram illustrating an example of a case in which a display error occurs on a touch screen panel when a noise signal such as a radio signal is introduced into the touch display device.

6(a) is a diagram illustrating a case in which touch sensing proceeds from the top of the touch screen panel TSP in a downward direction, and (b) shows a case in which touch sensing proceeds in a direction from the bottom to the top of the touch screen panel TSP. This is a diagram showing the case.

In each case, the case where there are 10 group multiplexers (MUX) used in the touch sensing circuit 194 is shown as an example, and blurring occurs in block units of the touch screen panel (TSP) due to noise such as a radio signal. (Dim) occurs. In particular, considering the sensing order of the touch screen panel (TSP), it can be seen that block dimming occurs in the first multiplexer (1st MUX) that performs touch sensing.

7 is a diagram showing a signal timing diagram in which noise such as a radio signal is introduced into a touch display device, and FIGS. 8 and 9 are diagrams showing circuit operation when a display error occurs due to noise such as a radio signal.

Here, for touch sensing of the touch screen panel TSP, 10 group multiplexers MUX0 to MUX9 are connected to the touch sensing circuit 194, and each group multiplexer MUX0 to MUX9 is connected to a first multiplexer MUX_0. ) and a second multiplexer MUX_1. 7 to 9, in the case of the touch display device 100 in which the display mode and the touch mode are temporally divided, a group multiplexer connected to the touch sensing circuit 194 before entering the display mode or the touch mode ( Among MUX0 to MUX9, the first multiplexer MUX_0 maintains a turn-off state, and the touch screen panel TSP is connected to the common voltage Vcom through the second multiplexer MUX_1.

In this state, when high-output noise such as a radio signal flows into the touch display device 100, charges are accumulated in the common voltage Vcom line and the potential of the common voltage Vcom rises.

When the touch mode is entered in a state where charges due to high output noise are accumulated in the common voltage (Vcom) line, the first multiplexer (MUX0_0) of the first group multiplexer (MUX0) is turned on. At this time, the common voltage ( Charges accumulated in the Vcom) line flow into the first group multiplexer (MUX0), causing malfunction.

In this state, when the touch mode is terminated and the display mode is entered, the second multiplexer (MUX0_1) of the first group multiplexer (MUX0) is turned on and the common voltage (Vcom) must be applied to the touch screen panel (TSP). , Since the common voltage (Vcom) is floating due to a malfunction of the first group multiplexer (MUX0), blurring occurs in the block of the touch screen panel (TSP) to which the first group multiplexer (MUX0) is connected. will be.

On the other hand, since the interval between the time when the second group multiplexer (MUX1) is turned on and the time when the first group multiplexer (MUX0) is turned on is relatively short, the possibility that noise such as a radio signal may be introduced is low. , Since the incoming noise is not large, it can be said that the possibility of causing a malfunction of the second group multiplexer MUX1 or blurring of the touch screen panel TSP is low.

To solve this problem, the touch circuit 190 is configured to independently control the connection between the touch screen panel (TSP) and the sensing unit (SSU) and to discharge noise when it is introduced.

10 is a diagram showing the configuration of a touch circuit according to an embodiment of the present invention.

Here, only one arbitrary group multiplexer among a plurality of group multiplexers (MUX) is shown as an example. Referring to FIG. 10, a touch circuit according to an embodiment of the present invention is connected between a sensing unit (SSU), a touch channel connected to a touch screen panel (TSP), and an inverted input terminal (-) of the sensing unit (SSU). A first multiplexer (MUX_0), a second multiplexer (MUX_1) connected between the touch channel and the non-inverting input terminal (+) of the sensing unit (SSU), and connected between the touch channel and the ground (GND) and the first multiplexer ( MUX_0) and a second multiplexer (MUX_1) and a discharge switch (SW_D) independently controlled. A common voltage Vcom is applied to the non-inverting input terminal (+) of the sensing unit SSU.

At this time, the inverter INV is not connected between the first multiplexer MUX_0 connected to the inverting input terminal (-) of the sensing unit SSU and the second multiplexer MUX_1 connected to the non-inverting input terminal (+) of the sensing unit SSU. . Therefore, since the first multiplexer MUX_0 and the second multiplexer MUX_1 are independently controlled, the first and second multiplexers MUX_0 and MUX_1 generate the first switching signal SW0 and the second switching signal SW1. As a result, each independently on-off operation may be performed. Due to this, it is possible to prevent a short circuit from occurring between the ground GND and the common voltage Vcom when the discharge switch SW_D is operated.

The discharge switch SW_D is a part for removing noise accumulated in the touch screen panel TSP before the first multiplexer MUX_0 or the second multiplexer MUX_1 operates in a display mode or a touch mode.

Therefore, before entering the display mode or the touch mode, the discharge switch (SW_D) is turned on for the discharge time (Dis_0) to discharge noise accumulated in the touch screen panel (TSP), thereby generating blocks in the display section. block dimming can be prevented.

Similarly, the first multiplexer MUX_0 and the second multiplexer MUX_1 connected to the sensing unit SSU constitute one group, and according to the pixel configuration of the touch screen panel TSP, the touch screen panel ( TSP) can be connected.

For example, the gate line GL of the touch screen panel TSP is divided into 10 blocks each having a certain number of columns, and a first multiplexer MUX_0 and a second multiplexer MUX_1 are provided for each block. In the case of configuring one group by connecting, ten groups of multiplexers MUX0 to MUX9 may be connected to the touch sensing circuit 194 .

In addition, although the first multiplexer MUX_0 and the second multiplexer MUX_1 have been described for the purpose of sensing a touch signal of the touch screen panel TSP or applying a common voltage Vcom to the touch screen panel TSP, Since it is used for the purpose of controlling a signal direction between the screen panel TSP and the sensing unit SSU, the multiplexer MUX may be expressed as a switching element such as a switch.

11 is a diagram showing a signal timing diagram for discharging noise such as a radio signal in the touch display device according to an embodiment of the present invention, and FIG. 12 is a diagram illustrating a circuit operation for discharging noise such as a radio signal.

Here, the case where 10 group multiplexers (MUX0 to MUX9) are connected to the touch sensing circuit 194 for touch sensing of the touch screen panel (TSP) is shown, and each group multiplexer (MUX0 to MUX9) is a sensing unit (SSU) It may include a first multiplexer MUX_0 connected to the inverting input terminal (-) of and a second multiplexer MUX_1 connected to the non-inverting input terminal (+).

11 and 12, in the touch display device 100 in which the display mode and the touch mode are temporally divided, a group multiplexer (MUX0) connected to the touch sensing circuit 194 before entering the display mode or the touch mode ~ MUX9), both the first multiplexer MUX_0 and the second multiplexer MUX_1 maintain a turned-off state.

In addition, the discharge switches (SW0_D to SW9_D) connected between the touch channel and the ground (GND) maintain a turned-on state.

Therefore, even if noise such as a radio signal flows into the touch display device 100 in this state, since it is discharged to the ground (GND) through the discharge switches (SW0_D to SW9_D), noise is not accumulated in the common voltage (Vcom) line. will not be

As a result, it is possible to prevent block dimming in a specific block of the touch screen panel TSP, in particular, a pixel connected to the first group multiplexer MUX0 in the display mode.

13 is a diagram illustrating signal timing for discharging noise such as a radio signal in a touch display device according to another embodiment of the present invention.

Since the touch display device 100 requires high-speed signal processing as the resolution increases, a time for discharging noise such as a radio signal cannot be maintained for a long time. Therefore, it is desirable to secure a discharge time (Dis_0) long enough to effectively discharge noise before entering the touch mode.

However, in some cases, when a high-output radio signal is introduced, it may be difficult to discharge all the introduced noise in one discharge time (Dis_0). Therefore, considering this case, the discharge switch SW_D is turned on during the first discharge time (Dis_0) at the time when the touch mode starts, and selectively, the second discharge time (Dis_0) at the time when the touch mode ends. During this time, the discharge switch SW_D may be turned on again to additionally discharge noise. This secondary discharge may selectively proceed.

14 is a diagram illustrating a timing diagram of a switching signal controlling a multiplexer to discharge noise such as a radio signal in a touch display device according to an embodiment of the present invention.

14, before entering the touch mode, the first switching signal SW0 applied to the first multiplexer MUX_0 and the second switching signal SW1 applied to the second multiplexer MUX_1 are set to a low level. is applied to turn off the first multiplexer MUX_0 and the second multiplexer MUX_1. Accordingly, even if noise is introduced into the touch screen panel TSP, the noise is not transmitted to the common voltage Vcom.

In this state, the discharge switching signal (SW2) applied to the discharge switch (SW_D) is applied at a high level to turn on the discharge switch (SW_D) so that the noise introduced into the touch screen panel (TSP) is grounded. (GND) causes the first discharge (Dis_0).

When the secondary discharge (Dis_1) is required at the time the touch mode ends, the discharge switch (SW_D) may be turned on again to proceed with additional noise discharge.

15 is a diagram showing the configuration of a touch circuit according to another embodiment of the present invention.

Referring to FIG. 15 , a touch circuit according to another embodiment of the present invention is provided between a sensing unit (SSU), a touch channel connected to a touch screen panel (TSP) and an inverted input terminal (-) of the sensing unit (SSU). The second multiplexer MUX_1 connected between the connected first multiplexer MUX_0, the touch channel and the non-inverting input terminal (+) of the sensing unit SSU, and the non-inverting input terminal (+) of the sensing unit SSU ) and the ground (GND) and a discharge switch (SW_D) independently controlled by the first multiplexer (MUX_0) and the second multiplexer (MUX_1), and the non-inverting input terminal (+) of the sensing unit (SSU) and It may be composed of a common voltage switch (SW_C) connected between the common voltage (Vcom).

The discharge switch SW_D is a part for removing noise accumulated in the touch screen panel TSP before the first multiplexer MUX_0 or the second multiplexer MUX_1 operates in a display mode or a touch mode.

The first multiplexer MUX_0 connected to the inverting input terminal (-) of the sensing unit SSU and the second multiplexer MUX_1 connected to the non-inverting input terminal (+) are connected through an inverter INV, thereby performing a first switching operation. When the first multiplexer MUX_0 is turned on by the signal SW0, the second multiplexer MUX_1 is automatically turned off.

However, the second switching signal SW1 and the discharging switching signal SW2 applied to the common voltage switch SW_C and the discharging switch SW_D are independently controlled from the first switching signal SW0.

Therefore, before entering the display mode or the touch mode, the second multiplexer MUX1 and the discharge switch SW_D are simultaneously turned on for a certain discharge time Dis_0 to reduce noise accumulated in the touch screen panel TSP. By discharging, it is possible to prevent block dimming occurring in the display section.

At this time, the common voltage switch SW_C is turned off during the discharge time Dis_0 during which the discharge switch SW_D is turned on so that the noise introduced into the touch screen panel TSP is connected to the common voltage Vcom line. should not accumulate.

Then, in the touch mode, the first switching signal SW0 is applied with a high level to turn on the first multiplexer MUX_0 and turn off the second multiplexer MUX_1. Conversely, in the display mode, the first switching signal SW0 is applied at a low level to turn off the first multiplexer MUX_0, turn on the second multiplexer MUX_1, and generate the common voltage switching signal SW_C. By applying a high level, the common voltage (Vcom) is controlled to be supplied to the touch screen panel (TSP) through the second multiplexer (MUX_1).

Here, the first multiplexer MUX_0 and the second multiplexer MUX_1 have been described for the purpose of sensing a touch signal of the touch screen panel TSP or applying a common voltage Vcom to the touch screen panel TSP. Since it is used for the purpose of controlling a signal direction between the touch screen panel (TSP) and the sensing unit (SSU), the multiplexer (MUX) may be expressed as a switching element such as a switch.

16 is a diagram showing the configuration of a touch circuit according to another embodiment of the present invention.

Referring to FIG. 16, the touch circuit according to another embodiment of the present invention does not unconditionally turn on the discharge switch SW_D before entering the touch mode, but checks whether noise is introduced into the touch screen panel TSP. and may be configured so that the discharge switch SW_D is turned on when noise is introduced.

To this end, a noise detection circuit 196 may be configured at the output terminal of the sensing unit SSU. The noise detection circuit 196 may include an analog-to-digital converter (ADC) connected to the output terminal of the sensing unit (SSU) and a noise determination circuit. The noise determination circuit determines whether the signal applied through the analog-to-digital converter (ADC) is noise, and if it is noise, outputs a discharge control signal (DIS_C) to perform an operation for discharging the noise.

The noise determination circuit may include a plurality of XNOR gates receiving output signals of analog-to-digital converters (ADC) as input signals and an AND gate receiving output signals of the plurality of XNOR gates. Here, a case of 11 XOR gates for receiving 12-bit analog-to-digital converter signals and AND gates receiving output signals of the 11 XOR gates as inputs is shown as an example.

The analog-to-digital converter (ADC) receives the touch sensing signal (TSS) transmitted from the touch screen panel (TSP) through the sensing unit (SSU). Then, the touch input level is fixed at 4095 or 0. Therefore, since the XNOR gate transfers the output signal of all 1s to the AND gate when all input signals are 1 or 0, the AND gate also outputs the output signal of 1 indicating the inflow of noise as the discharge control signal (DIS_C). will do

When the discharge control signal DIS_C of 1 is generated in the noise detection circuit 194, as described above, the second multiplexer MUX_1 connected to the common voltage Vcom is turned off and the discharge switch SW_D is turned off. The second switching signal SW1 and the discharging switching signal SW2 are controlled to turn on.

Meanwhile, in the touch display device 100 of the present invention, the operation of controlling the touch circuit 190 to discharge noise flowing into the touch screen panel TSP is the touch screen driving circuit 130 or various integrated circuits combined therewith. (IC).

For example, when parts of the touch screen driving circuit 130 and the data driving circuit 120 are configured as one integrated circuit (IC), this may be referred to as a SRIC (Source & Readout IC). In this case, the SRICs may be directly attached to the touch screen panel TSP through a COG (Chip On Glass) process, and the SRICs may be connected to the microcontrol unit 192 through the interface SPI.

Alternatively, a case in which a part of the touch screen driving circuit 130 is configured in the form of an integrated circuit (IC) may be referred to as a read out IC (ROIC).

Accordingly, the discharge control signal DIS_C generated by the noise detection circuit 194 may be applied to the SRIC, ROIC, or the timing controller 140 to control the noise discharge operation of the touch screen panel TSP.

Eventually, before entering the display mode or the touch mode, or when noise is detected in the touch screen panel (TSP), the discharge switch (SW_D) is turned on for a certain discharge time (Dis_0) to turn on the touch screen panel (TSP). ), it is possible to prevent block dimming occurring in the display section.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present invention. In addition, since the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are intended to explain, the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

100: touch display device
110: display panel
120: data driving circuit
130: gate driving circuit
121, 131: film
140: timing controller
150: power control circuit
160: source printed circuit board
170: control printed circuit board
180: connecting member
190: touch circuit
192: micro control unit
194: touch sensing circuit
196: noise detection circuit
300: touch channel

Claims (19)

sensing unit;
a first switching element connected between a touch channel connected to the touch screen panel and a first input terminal of the sensing unit;
a second switching element connected to the touch channel and the second input terminal of the sensing unit;
A discharge switch connected between the touch channel and the ground and independently controlled from the first switching element and the second switching element,
The touch circuit according to claim 1 , wherein the discharge switch is controlled to be turned on for a predetermined time before the touch screen panel enters a display mode or a touch mode.
According to claim 1,
A touch circuit in which a common voltage is applied to a second input terminal of the sensing unit.
According to claim 1,
The switching element is a touch circuit that is a multiplexer or a switch.
delete According to claim 1,
The touch circuit of claim 1 , wherein the first switching element is turned on in a touch mode and the second switching element is turned on in a display mode.
According to claim 1,
A touch circuit further comprising a noise detection circuit connected to an output terminal of the sensing unit.
According to claim 6,
The noise detection circuit
an analog-to-digital converter connected to an output terminal of the sensing unit;
a plurality of XNOR gates receiving the output signal of the analog-to-digital converter as an input signal; and
A touch circuit comprising an AND gate receiving output signals of the plurality of XNOR gates.
a display panel on which a plurality of data lines and a plurality of gate lines are disposed, and a plurality of subpixels are disposed;
a data driving circuit driving the plurality of data lines;
a gate driving circuit for driving the plurality of gate lines;
a timing controller controlling the data driving circuit and the gate driving circuit; and
A touch circuit configured to sense a touch by sequentially driving a plurality of common electrodes constituting the display panel;
the touch circuit
sensing unit;
a first switching element connected between a touch channel connected to the display panel and a first input terminal of the sensing unit;
a second switching element connected to the touch channel and the second input terminal of the sensing unit;
A discharge switch connected between the touch channel and the ground and independently controlled from the first switching element and the second switching element,
The touch display device according to claim 1 , wherein the discharge switch is controlled to be turned on for a predetermined time before the display panel enters a display mode or a touch mode.
sensing unit;
a first switching element connected between a touch channel connected to the touch screen panel and a first input terminal of the sensing unit;
a second switching element connected between the touch channel and the second input terminal of the sensing unit;
a discharge switch connected between the second input terminal of the sensing unit and the ground and controlled independently of the first switching element and the second switching element; and
A common voltage switch connected between a second input terminal of the sensing unit and a common voltage,
The second switching element and the discharge switch are controlled to be turned on for a predetermined time before the touch screen panel enters a display mode or a touch mode.
According to claim 9,
The switching element is a touch circuit that is a multiplexer or a switch.
delete According to claim 9,
The touch circuit further comprises an inverter connected between the first switching element and the second switching element.
According to claim 10,
The touch circuit of claim 1 , wherein the first switching element is turned on in a touch mode, and the second switching element and the common voltage switch are controlled to be turned on in a display mode.
According to claim 9,
A touch circuit further comprising a noise detection circuit connected to an output terminal of the sensing unit.
15. The method of claim 14,
The noise detection circuit
an analog-to-digital converter connected to an output terminal of the sensing unit;
a plurality of XNOR gates receiving the output signal of the analog-to-digital converter as an input signal; and
A touch circuit comprising an AND gate receiving output signals of the plurality of XNOR gates.
a display panel on which a plurality of data lines and a plurality of gate lines are disposed, and a plurality of subpixels are disposed;
a data driving circuit driving the plurality of data lines;
a gate driving circuit for driving the plurality of gate lines;
a timing controller controlling the data driving circuit and the gate driving circuit; and
A touch circuit configured to sense a touch by sequentially driving a plurality of common electrodes constituting the display panel;
the touch circuit
sensing unit;
a first switching element connected between a touch channel connected to the touch screen panel and a first input terminal of the sensing unit;
a second switching element connected between the touch channel and the second input terminal of the sensing unit;
a discharge switch connected between the second input terminal of the sensing unit and the ground and controlled independently of the first switching element and the second switching element; and
A common voltage switch connected between a second input terminal of the sensing unit and a common voltage,
The second switching element and the discharge switch are controlled to be turned on for a predetermined time before the touch screen panel enters a display mode or a touch mode.
A display panel on which a plurality of data lines, a plurality of gate lines, and a plurality of subpixels are disposed, a data driving circuit driving the plurality of data lines, a gate driving circuit driving the plurality of gate lines, and the data driving circuit A method of driving a touch display device including a timing controller for controlling the circuit and the gate driving circuit, and a touch circuit for sensing a touch by sequentially driving a plurality of common electrodes constituting the display panel, the method comprising:
Discharging noise introduced into the display panel by turning on a discharge switch connected between a touch channel of the display panel and a ground before entering a display mode or a touch mode;
turning on a first switching element connected between the touch channel and the sensing unit of the touch circuit in a touch mode; and
and turning on a second switching element connected between the touch channel and the sensing unit in a display mode.
18. The method of claim 17,
Before the display mode or the touch mode is terminated, turning on a discharge switch connected between the touch channel of the display panel and the ground to additionally discharge noise introduced into the display panel. .
18. The method of claim 17,
detecting noise introduced into the display panel; and
The driving method further comprising controlling an operation of the discharge switch according to the detection result.

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