KR102384762B1 - Touch sensing driving circuit - Google Patents

Abstract

The present invention relates to a touch sensing driving circuit. The touch sensing driving circuit is a touch sensing driving circuit in which a gate driving unit for displaying an image is operated during a display driving time TD and a touch sensing unit sensing a touch input is operated during a touch sensing time TS, a timing controller a touch driving circuit TPIC that receives the blank reset signal BRST transmitted to the gate driver, and a touch synchronization signal ( Tsync) as a touch controller (MCU).

Description

Touch sensing driving circuit {TOUCH SENSING DRIVING CIRCUIT}

The present invention relates to a touch sensing driving circuit.

A touch sensor capable of inputting information by touch on the screen of a display is being applied to various displays such as a laptop computer, a monitor, and a home appliance as well as a portable information device such as a smart phone.

The touch technology applied to the display is divided into an add-on type and an in-cell type according to the location of the touch sensor. The add-on type is an external type in which a touch screen panel is attached to the display panel, and the in-cell type is an integrated type in which the display panel and the touch screen are integrated by embedding a touch electrode in the display panel.

The in-cell type is further advanced for slimming the display device and is being developed into an Advanced In-cell Touch (AIT) display device in which a common electrode of a liquid crystal display is divided and used as a touch electrode.

In an in-cell touch display device including an AIT display device, in order to reduce the mutual influence due to coupling between pixels and touch sensors, a plurality of display driving times for dividing and driving pixels into a plurality of blocks in each frame period; , divides the time into a plurality of touch sensing times, and drives the touch display panel so that the display driving time and the touch sensing time alternate.

Also, the in-cell touch display apparatus may operate in a VBS mode (Vertical Blanking Sensing Mode) in which touch sensing is performed in a vertical blanking period among the operation periods of the display panel.

In this case, in the display driving time, the gate driving circuit should sequentially drive the gate lines of the corresponding block, and in the touch sensing time between the display driving times, the gate driving circuit should maintain sequential circuit characteristics. To this end, the gate driving circuit requires different control signals at the display driving time and the touch sensing time.

To this end, the timing controller needs to generate and supply different control signals required for the display driving time and the touch sensing time. For this reason, the number of output pins of the timing controller must be increased, and the number of signal lines on the printed circuit board and the routing area corresponding thereto must be increased, so there is a problem of cost increase.

1 and 2 are diagrams illustrating a timing controller and a touch sensing unit included in a conventional touch and dual display device.

Specifically, referring to FIGS. 1 and 2 , a conventional display device includes a timing controller 10 and a touch sensing unit 60 . A conventional display device includes an advanced-in-cell touch (AIT) display device and may operate in a VBS mode.

Here, the timing controller 100 receives image data and timing signals from a host system (not shown). In this case, the timing signal includes a data enable signal, a vertical sync signal, a horizontal sync signal, a reset signal BRST, and a touch sync signal Tsync.

The touch driving circuit (TPIC) 62 supplies the common voltage Vcom to the signal line TL during the display driving time P1 and the touch driving signal Vtouch to the signal line TL during the touch sensing time P2. ) is supplied. In this case, the touch driving circuit 62 supplies the common voltage Vcom or the touch driving signal Vtouch to the signal line TL based on the reset signal BRST received from the timing controller 10 .

The touch controller (MCU) 64 receives a feedback signal from the corresponding touch electrode TE. Then, the touch controller 64 differentially amplifies the touch driving signal Vtouch and the feedback signal for each touch electrode TE to sense the change in the self-capacitance (signal delay amount) of each touch 　 electrode TE due to the touch. Generates sensing information. Next, the touch controller 64 processes the sensing information to calculate touch coordinate information, and outputs the touch coordinate information to a host system (not shown). In this case, the touch controller 64 determines whether it is the touch sensing time TS using the touch synchronization signal Tsync received from the timing controller 10 .

However, the display device including the conventional advanced-in-cell touch (AIT) type GIP has a larger number of output signal wirings than the normal model, and as the number of output signal wirings increases, the number of pins of the timing controller 10 increases, so that the overall There was a problem in that the size of the PCB increased and the design became complicated.

In addition, as the timing controller 10 simultaneously provides the reset signal BRST and the touch synchronization signal Tsync to the touch sensing unit 60, mutual interference between the reset signal BRST and the touch synchronization signal Tsync causes There was a problem that a defect occurred in the touch sensing.

An object of the present invention is to provide a touch sensing driving circuit capable of reducing the number of output pins of a timing controller and simplifying a layout by integrating and replacing the touch synchronization signal Tsync with the blank reset signal BRST.

In addition, the present invention provides a touch sensing driving circuit capable of reducing a touch sensing recognition error caused by mutual interference of two signals by integrating and replacing the touch synchronization signal Tsync with the blank reset signal BRST. for other purposes.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned may be understood by the following description, and will be more clearly understood by the examples of the present invention. It will also be readily apparent that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the appended claims.

In one aspect of the touch sensing driving circuit according to an embodiment of the present invention, a gate driver for displaying an image is operated during a display driving time TD, and sensing a touch input during a touch sensing time TS. A touch sensing driving circuit in which a touch sensing unit operates, the touch driving circuit (TPIC) receiving a blank reset signal BRST transmitted from a timing controller to the gate driving unit, and the touch driving circuit transmitted from the timing controller to the touch driving circuit and a touch controller MCU that inverts the blank reset signal BRST and uses it as a touch synchronization signal Tsync.

In addition, the touch controller may include an inverter that logically inverts and outputs the blank reset signal BRST, and a buffer that delays the output signal of the inverter for a predetermined time.

Also, the touch controller MCU may include a plurality of buffers connected in series.

In addition, a gate driver including a plurality of GIP blocks for respectively driving a plurality of blocks in a plurality of display driving periods TD by dividing the gate lines of the panel for a touch display into a plurality of blocks, and the blank reset signal BRST ) may be generated and output, and a timing controller that does not output the touch synchronization signal Tsync may be further included.

In addition, the display device further includes a panel including a plurality of touch electrode rows included in the pixel array, wherein the panel includes a plurality of touch electrodes TE arranged in a longitudinal direction of a data line, and the plurality of touch electrodes TE It may include a plurality of signal lines TL individually connected to the touch controller and connected to the touch controller.

In addition, the touch driving circuit provides a common voltage Vcom to the plurality of touch electrodes TE during the display driving time TD, and provides the plurality of touch electrodes TE during the touch sensing time TS. A touch driving signal Vtouch may be provided to the .

In addition, the touch controller receives a feedback signal for the touch driving signal Vtouch provided to the plurality of touch electrodes TE during the touch sensing time TS through the plurality of signal lines TL, A change in self-capacitance of the touch electrode TE may be sensed through differential amplification of the touch driving signal Vtouch and the feedback signal, and touch coordinate information may be calculated.

Another aspect of the touch sensing driving circuit according to an embodiment of the present invention is a touch sensing driving circuit that operates by dividing the display driving time TD and the touch sensing time TS based on the touch synchronization signal Tsync. In the above, a data driver charging a data voltage to the pixel array of the panel during the display driving time TD, and a touch sensing for sensing touch inputs on a plurality of touch electrodes TE built in the panel during the touch sensing time TS and a timing controller providing a blank reset signal BRST used to generate the touch synchronization signal Tsync to the data driver and the touch sensing unit, wherein the touch sensing unit includes the blank reset signal BRST ) based on a touch driving circuit providing different voltages to the touch electrode TE at the display driving time TD and the touch sensing time TS, and inverting the blank reset signal BRST. and a touch controller that generates and uses the touch synchronization signal Tsync and calculates touch coordinate information on the touch electrode TE.

In addition, the touch controller may include an inverter that logically inverts and outputs the blank reset signal BRST, and a buffer that delays the output signal of the inverter for a predetermined time.

In addition, the minimum interval G1 between the rising time of the blank reset signal BRST and the polling time of the touch synchronization signal Tsync is the falling time of the blank reset signal BRST and the touch synchronization signal Tsync. It may be equal to the minimum time (G2) between the rising times of .

According to the present invention, by integrating and replacing the touch synchronization signal Tsync with the blank reset signal BRST, the number of output pins of the timing controller can be reduced and the layout of the driving circuit can be simplified. Through this, the production cost of the driving circuit can be reduced, the overall size of the layout can be reduced, and the layout design can be optimized.

In addition, according to the present invention, by integrating and replacing the touch synchronization signal Tsync with the blank reset signal BRST, a touch sensing recognition error caused by mutual interference between the two signals can be reduced, and a response according to a user's touch operation you can speed up

1 and 2 are diagrams illustrating a timing controller and a touch sensing unit included in a conventional touch display device.
3 is a block diagram schematically illustrating a touch sensing driving circuit according to an embodiment of the present invention.
4 is a driving waveform diagram of a panel according to an embodiment of the present invention.
5 is a driving timing diagram of a panel according to an embodiment of the present invention.
6 is a diagram illustrating a signal connection relationship between a timing controller and a gate driver via a PMIC according to an embodiment of the present invention.
7 is a diagram illustrating a signal connection relationship between a timing controller and a touch sensing unit according to an embodiment of the present invention.
8 is a driving waveform diagram of a touch sensing unit according to an embodiment of the present invention.

The above-described objects, features and advantages will be described below in detail with reference to the accompanying drawings, and accordingly, those of ordinary skill in the art to which the present invention pertains will be able to easily implement the technical idea of the present invention. In describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

Hereinafter, a touch sensing driving circuit according to an embodiment of the present invention will be described in detail with reference to the drawings.

3 is a block diagram schematically illustrating a touch sensing driving circuit according to an embodiment of the present invention. 4 is a driving waveform diagram of a panel according to an embodiment of the present invention. 5 is a driving timing diagram of a panel according to an embodiment of the present invention. 6 is a diagram illustrating a signal connection relationship between a timing controller and a gate driver via a PMIC according to an embodiment of the present invention.

First, referring to FIG. 3 , a touch display device according to an embodiment of the present invention includes a timing controller 100 , a PMIC 200 , a gate driver 300 , a data driver 400 , a panel 500 , and a touch A sensing unit 600 and the like are provided.

The timing controller 100 receives image data and timing signals from a host system (not shown). The timing signals include a dot clock, a data enable signal, a vertical sync signal, and a horizontal sync signal. Since the vertical synchronization signal and the horizontal synchronization signal can be generated by counting the data enable signal, they can be omitted.

The timing controller 100 supplies the image data supplied from the host system to the data driver 400 by performing various image processing such as image quality correction.

The timing controller 100 generates data control signals DCS for controlling the operation timing of the data driver 400 using the timing signals supplied from the host system and supplies them to the data driver 400 . For example, the data control signals DCS include a source start pulse used to control latch timing of data, a source sampling clock, a source output enable signal to control an output period of data, and the like.

The timing controller 100 generates simple timing signals TC used to generate gate control signals for controlling the driving timing of the gate driver 300 using the timing signals supplied from the host system to the PMIC 200 . supply For example, the simple timing signals TC include first and second initial start pulses iVST1 and iVST2 (refer to FIG. 6), an on clock (ON_CLK; see FIG. 6), an off clock (OFF_CLK; see FIG. 6), and a blank reset signal BRST (refer to FIG. 6 ).

The timing controller 100 uses the timing signals supplied from the host system to time-divide each frame period into at least one display driving time TD1 to TDN and at least one touch sensing time TS1 to TSN. A blank reset signal for time division (BRST) is generated and supplied to the PMIC 200 and the 　touch 　 sensing unit 600 .

The blank reset signal BRST is an inverted signal of the touch synchronization signal Tsync, and the PMIC 200 may generate and use the touch synchronization signal Tsync using the blank reset signal BRST. However, the present invention is not limited thereto, and in another embodiment of the present invention, the PMIC 200 may directly receive and use the touch synchronization signal Tsync from the timing controller 100 .

The timing controller 100 stores the image data received from the host system in the internal memory, and supplies the image data stored in the memory to the data driver 400 at a reading speed faster than the writing speed at each display driving time TD. By controlling the operation timings of the gate driver 300 and the data driver 400 , the data voltage is written into the pixel array of the panel 500 at the display driving time TD. The timing controller 100 does not supply image data to the data driver 400 during the touch sensing time TS.

The PMIC 200 generates and supplies various driving voltages required by the touch display device, and the touch generated using the simple timing signals TC and the blank reset signal BRST supplied from the timing controller 100 . The gate control signals GCS for controlling the gate driver 300 are generated and supplied using the synchronization signal Tsync.

The PMIC 200 uses the input voltage supplied from the outside to configure all the circuits of the 　 touch and combined display device, that is, the timing controller 100 , the gate driver 300 , the data driver 400 , the panel 500 , and the touch sensing unit. Various driving voltages necessary for driving the 600 are generated and output. For example, the PMIC 200 uses the input voltage to provide digital driving voltages VCC and GND supplied to the timing controller 100 , the data driver 400 , and the touch sensing unit 600 , and to the panel 500 . The common voltage Vcom supplied, the analog driving voltage VDD supplied to the data driver 400 , the gate-on voltage VGH and the gate-off voltage VGL supplied to the gate driver 300 are generated and output. .

The PMIC 200 uses the touch synchronization signal Tsync generated based on the simple timing signals TC supplied from the timing controller 100 and the blank reset signal BRST to perform the operation timing of the gate driver 300 . The gate control signals GCS are generated, level-shifted, and supplied to the gate driver 300 .

For example, the PMIC 200 includes an initial start pulse (iVST1, iVST2; see FIG. 6) supplied from the timing controller 100, an on clock (ON_CLK; see FIG. 6), an off clock (OFF_CLK; see FIG. 6), Start pulses VST1 and VST2 (refer to FIG. 6 ) for instructing the gate driver 300 to start driving for each frame using a blank reset signal BRST (refer to FIG. 6 ), and scan output at each display driving time TD A plurality of shift clocks GCLK1 to GCLK8 (refer to FIG. 6 ), etc., used as the ?, are generated and level-shifted to increase the swing width of the generated gate control signals GCS, and then supplied to the gate driver 300 .

In response to the data control signal supplied from the timing controller 100 , the data driver 400 converts the image data supplied from the timing controller 100 into an analog signal at the display driving time TD to display the data of the panel 500 . It is supplied to the lines DL. The data driver 400 subdivides a reference gamma voltage set supplied from a gamma voltage generator (not shown) that is built into itself or is separately provided outside (not shown) into gray voltages respectively corresponding to gray values of data. The data driver 400 converts digital data into positive or negative analog data voltages (Vdata+, Vdata-) at the display driving time TD using the subdivided grayscale voltages, and the voltage polarity is inverted in a predetermined unit. The data voltages Vdata+ and Vdata- are respectively supplied to the data lines DL of the panel 500 .

The gate driver 300 sequentially drives the gate lines GL of the panel 500 at each display driving time TD in response to the gate control signal GCS supplied to the PMIC 200 . At each display driving time TD, the gate driver supplies a scan pulse of the gate-on voltage VGH to the gate line GL of the corresponding block for each scan period, and during the remaining period when other gate lines GL are driven, the gate driver The off voltage (VGH) is supplied. At each 　 touch sensing time TS, the gate driver 300 does not output a scan pulse.

To this end, the gate driver 300 divides the gate lines GL into a plurality of display driving times TD1 to TDN, respectively, and drives a plurality of GIP blocks (#1 to #N; see FIG. 6 ) and adjacent ones. It includes a bridge GIP circuit (BGIP1, BGIP2, ...) that is located between the GIP blocks and maintains the sequential circuit characteristics of the GIP circuit at the touch sensing time (TS) between adjacent display driving times, and includes GIP blocks Each of (#1 to #N) includes a plurality of GIP circuits for individually and sequentially driving a plurality of gate lines of a corresponding block. In addition, the gate driver 300 further includes a dummy circuit (not shown) for stably driving the GIP circuit.

The panel 500 has a touch and display function, displays an image through a pixel array in which pixels P are arranged in a matrix form, and uses a common electrode combined 　 touch 　 electrode (TE) to determine whether 　 touch is a capacitance method. sense

The panel 500 may be an organic light emitting diode display panel or a liquid crystal display panel, and in the embodiment of the present invention, a liquid crystal display panel will be described as an example. As the capacitive touch method, either a mutual capacitance touch method or a self-capacitance touch method may be used. In the embodiment of the present invention, the self-capacitance touch method will be described as an example.

Each of the pixels P of the panel 500 includes a thin film transistor TFT connected to a gate line GL and a data line DL, a liquid crystal capacitor Clc and a storage capacitor connected to the thin film transistor TFT Cst) is provided. The liquid crystal capacitor Clc charges a difference voltage between the data signal supplied to the pixel electrode through the thin film transistor TFT and the common voltage supplied to the common electrode and touch electrode TE, and drives the liquid crystal according to the charged voltage. to adjust the light transmittance. The storage capacitor Cst stably maintains the voltage charged in the liquid crystal capacitor Clc.

The panel 500 includes a plurality of touch electrode columns included in a pixel array, and each of the plurality of touch electrode columns includes a plurality of touch 　 electrodes TE and a plurality of touch electrodes arranged in the longitudinal direction of the data line DL. It includes a plurality of signal lines TL individually connected to the TE and connected to the touch sensing unit 600 . The plurality of touch electrodes TE are formed by dividing a common electrode formed in a pixel array, and each touch electrode TE is formed to have a predetermined size including a plurality of pixels in consideration of the size of the touch point.

In response to the touch synchronization signal Tsync generated based on the blank reset signal BRST supplied from the timing controller 100 , the touch sensing unit 600 generates the signal lines TL at the touch sensing time TS. A touch driving signal Vtouch is supplied to the touch electrode TE through the Subsequently, the touch sensing unit 600 receives a feedback signal from the corresponding touch electrode TE. The touch sensing unit 600 differentially amplifies the touch driving signal Vtouch and the feedback signal for each touch electrode TE to sense and sense a change in self-capacitance (signal delay amount) of each touch electrode TE due to the touch. Information is generated, the sensed information is signal-processed to calculate touch coordinate information, and the touch coordinate information is output to the host system.

In FIG. 3 , the touch sensor 600 receives the blank reset signal BRST from the timing controller 100 , but the present invention is not limited thereto, and the touch sensor 600 receives the blank reset signal BRST from the PMIC 200 . The blank reset signal BRST′ transmitted to the gate driver 300 may be received and an operation may be performed based on the received blank reset signal BRST′.

The touch/sensing unit 600 may be integrated as a touch IC, integrated as a driving IC together with the data driving unit 400 , or integrated as a driving IC together with the data driving unit 400 and the timing controller 100 . The data driver 400 may include at least one IC and may be connected to the panel 500 .

The gate driver 300 is formed together with the thin film transistor array of the panel 500 in a GIP (Gate In Panel) method and is embedded in the non-display area.

Referring to FIG. 4 , in the first display driving time TD1 indicated by the touch sync signal Tsync generated based on the blank reset signal BRST, the gate driving unit 300 operates the first GIP block #1; FIG. 6) sequentially drives the gate lines GL11 to G1i, the data driver 400 supplies the data voltages Vdata+ and Vdata- to the data lines DL, and the touch 　 sensing unit 600 is powered from the power supply. The data voltages Vdata+ and Vdata− are written in the pixels of the first block by supplying the common voltage Vcom to the touch electrodes TE through the signal lines TL.

In the first touch sensing time TS1 indicated by the touch synchronization signal Tsync generated based on the blank reset signal BRST, the touch sensing unit 600 is connected to the touch electrodes TE through the signal lines TL. A touch driving signal Vtouch is supplied to each, and feedback signals from the corresponding touch electrodes TE are received through the signal lines TL to sense a touch.

Subsequently, in the second display driving time TD2 , the gate lines GL21 to GL2i of the second GIP block #2 of the gate driver 300 are sequentially driven and data is transmitted to the pixels of the second block as described above. The voltages Vdata+ and Vdata- are written, and then, as described above in the touch sensing time TS2, the touch 　 electrodes TE are driven to sense whether the touch is 　.

The display driving time TD and the touch sensing time TS are alternately repeated. As the gate lines GLN1 to GLNi of the N-th block #N are sequentially driven, the data voltages Vdata+ and Vdata- are written to the pixels of the N-th block. Subsequently, during the touch sensing time TSN, as described above, the touch 　 electrodes TE may be driven to sense a touch.

Meanwhile, as shown in FIG. 5 , at each touch sensing time TS, the touch/sensing unit 600 performs the gate lines GL and data lines DL through the gate driver 300 and the data driver 400 . ) by supplying the touch 　 driving signal (Vtouch) to load-free driving, thereby minimizing the RC load (resistor capacitor load) of the touch 　 electrode (TE) and signal line (TL) to improve the touch sensing sensitivity. there is.

To this end, an output selector (not shown) may be additionally provided at an output terminal of the gate driver 300 and an output terminal of the data driver 400 , respectively. The output selector provided at the output terminal of the gate driver 300 selects and outputs the scan signal supplied from the gate driver 300 at the display driving time TD in response to the touch driving signal Vtouch, and outputs the touch sensing time TS ), the touch driving signal Vtouch supplied from the touch sensing unit 600 may be selected and output. The output selector provided at the output terminal of the data driver 400 selects and outputs the data signal supplied from the data driver 400 at the display driving time TD in response to the touch synchronization signal Tsync, and 　touch sensing time ( TS) may select and output the touch driving signal Vtouch supplied from the touch sensing unit 600 .

Here, the display driving time TD and the touch sensing time TS may be divided based on the touch synchronization signal Tsync generated using the blank reset signal BRST received from the timing controller 100 . . In this case, the touch synchronization signal Tsync is an inverted signal of the blank reset signal BRST.

Also, in another embodiment of the present invention, the touch synchronization signal Tsync may be a signal obtained by delaying the blank reset signal BRST for a predetermined time. In this case, the predetermined time may be smaller than the display driving time TD or the touch sensing time TS. A detailed description thereof will be provided later.

6 is a diagram illustrating a signal connection relationship between a timing controller and a gate driver via a PMIC according to an embodiment of the present invention.

Referring to FIG. 6 , as shown in FIG. 6 , the timing controller 100 includes a plurality of initial start pulses iVST1 and iVST2 , an on clock ON_CLK, an OFF clock OFF_CLK, and a blank reset signal BRST. simple timing signals TC are supplied to the PMIC 200 through each transmission line.

At this time, the timing controller 100 supplies the blank reset signal BRST to the touch sensing unit 600 and the PMIC 200 . That is, the touch sensing unit 600 shares a transmission line for supplying the blank reset signal BRST from the timing controller 100 to the PMIC 200 .

The PMIC 200 generates the gate control signal GCS by using the simple timing signals TC supplied from the timing controller 100 and the touch synchronization signal Tsync generated based on the blank reset signal BRST. do. The gate control signal GCS includes start pulses VST1 and VST2, a plurality of shift clocks, for example, eight shift clocks CLK1 to CLK8, and a reset signal BRST', and the gate control signal GCS ) is supplied to the gate driver 300 through each transmission line. A method of generating the touch synchronization signal Tsync generated based on the blank reset signal BRST will be described later with reference to FIG. 7 .

The start pulses VST1 and VST2 serve to instruct the start of the operation of the gate driver 300 at the display driving time TD1 for each frame. The PMIC 200 level-shifts the initial start pulses iVST1 and iVST2 supplied from the timing controller 100 and supplies them to the gate driver 300 as start pulses VST1 and VST2 . Two start pulses VST1 and VST2 having a phase difference so that high sections do not overlap each other are respectively supplied to first and second gate drivers (not shown) that alternately drive gate lines on both sides of the panel 500 . If the gate driver 300 is not divided, only one start pulse VST may be supplied to the gate driver 300 .

The PMIC 200 generates and level-shifts the shift clocks CLK1 to CLK8 at each display driving time TD using the on clock ON_CLK and the OFF clock OFF_CLK, and supplies them to the gate driving unit 300 . The shift clocks GCLK1 to GCLK8 supplied from the PMIC 200 to the gate driver 300 rise sequentially in response to the rising time of the on clock ON_CLK, and sequentially in response to the falling time of the off clock OFF_CLK , and has a form in which adjacent shift clocks and some sections overlap each other. In the gate driver 300 , each of the GIP blocks #1, #2, ..., #N sequentially alternately selects the shift clocks GCLK1 to GCLK8 to sequentially select the phase shifted scan outputs GL11 to GL11 to GL1i, GL21 to GL2i, ..., GLN11 to GLNi).

The reset signal BRST' is supplied to initialize the dummy circuit and the GIP circuit included in the gate driver 300 in the blank period of the vertical synchronization signal. The pulse of the reset signal DRST' is supplied to the dummy circuit or the GIP circuit of the gate driver 300 in the blank period before the start pulse VST1, and drives the dummy circuit or the GIP circuit for stable initial driving. serves as a guide. The PMIC 200 level-shifts the blank reset signal BRST supplied from the timing controller 100 and supplies it to the gate driver 300 as a reset signal BRST'.

7 is a diagram illustrating a signal connection relationship between a timing controller and a touch sensing unit according to an embodiment of the present invention. 8 is a driving waveform diagram of a touch sensing unit according to an embodiment of the present invention.

Referring to FIG. 7 , the touch sensing unit 600 according to an embodiment of the present invention receives a blank reset signal BRST from the timing controller 100 .

The touch sensing unit 600 includes a touch driving circuit (TPIC) 610 and a touch controller (MCU) 620 . In this case, the touch driving circuit 610 and the touch controller 620 receive a common blank reset signal BRST from the timing controller 100 .

The touch driving circuit 610 supplies the common voltage Vcom to the touch electrode TE through the signal line TL for the display driving time TD, and through the signal line TL for the touch sensing time TS. A touch driving signal Vtouch is supplied to the touch electrode TE. At this time, the touch driving circuit 610 transmits the common voltage Vcom or the touch 　 driving signal Vtouch based on the blank reset signal BRST received from the timing controller 10 through the signal line TL to the touch electrode TE ) is supplied to

For example, when the blank reset signal BRST has a low logic level, the touch driving circuit 610 supplies the common voltage Vcom to the touch electrode TE. Conversely, when the blank reset signal BRST has a high logic level, the touch driving circuit 610 supplies the touch driving signal Vtouch to the touch electrode TE.

The touch controller 620 receives a feedback signal from the corresponding touch electrode TE while the touch driving circuit 610 supplies the touch driving signal Vtouch to the touch electrode TE. Then, the touch controller 620 differentially amplifies the touch driving signal Vtouch and the feedback signal for each touch electrode TE to sense the change in self-capacitance (signal delay amount) of each touch 　 electrode TE due to the touch. Generates sensing information. Next, the touch controller 620 processes the sensing information to calculate touch coordinate information, and outputs the touch coordinate information to a host system (not shown). In this case, the touch controller 620 generates a touch synchronization signal Tsync based on the blank reset signal BRST received from the timing controller 10 , and uses the touch synchronization signal Tsync to determine the touch sensing time TS. decide whether or not

The touch controller 620 includes an inverter 622 that logically inverts and outputs the blank reset signal BRST, and a buffer 624 that delays the output signal of the inverter for a predetermined time.

In general, when the rising time of the blank reset signal BRST and the polling time of the touch synchronization signal Tsync overlap, there may be a problem in that an error temporarily occurs in touch sensing. Accordingly, the touch controller 620 delays the inverted signal of the blank reset signal BRST by a predetermined time using the buffer 624 , so that the rising time of the blank reset signal BRST and the polling of the touch synchronization signal Tsync You can make sure that the times do not overlap. Through this, it is possible to stabilize the touch sensing section in the display device combined with touch, and thus, the recognition rate of touch sensing can be improved.

Referring to FIG. 8 , the touch synchronization signal Tsync has a polling time T2 delayed by a first time G1 from the rising time T1 of the blank reset signal BRST by the buffer 624 . In other words, the rising time T1 of the blank reset signal BRST and the falling time T2 of the touch synchronization signal Tsync do not occur simultaneously and have an interval of the first time G1 .

Similarly, the falling time T3 of the blank reset signal BRST and the rising time T4 of the touch synchronization signal Tsync also have an interval of the second time G2 . In this case, the second time period G2 may be the same as the first time period G1 .

In this case, the touch sensing unit 600 may provide the touch driving signal Vtouch to the touch electrode TE through the signal line TL and receive a feedback signal for the touch driving signal Vtouch.

Here, the display driving time TD may be from the rising time T0 of the touch synchronization signal Tsync to the rising time T1 of the blank reset signal BRST. The touch sensing time TS may be from the polling time T2 of the touch synchronization signal Tsync to the polling time T3 of the blank reset signal BRST. Through this, the touch display device of the present invention can normally perform an operation of displaying an image on a panel and an operation of sensing a user's touch without mutual interference, and can minimize an error in touch recognition.

In an embodiment of the present invention, it is illustrated that the touch controller 620 includes only one buffer 624 as an example, but the present invention is not limited thereto. For example, although not clearly shown in the drawings, in another embodiment of the present invention, the touch controller 620 may adjust the delay time of the touch synchronization signal Tsync by using the plurality of buffers 624 .

Through this, the touch sensing driving circuit of the present invention integrates and replaces the touch synchronization signal Tsync with the blank reset signal BRST. A touch sensing recognition error may be reduced, and a reaction speed according to a user's touch operation may be increased.

In addition, the touch sensing driving circuit of the present invention may reduce the number of output pins of the timing controller and simplify the layout of the driving circuit by integrating and replacing the touch synchronization signal Tsync with the blank reset signal BRST. Through this, the production cost of the driving circuit can be reduced, the overall size of the layout can be reduced, and the layout design can be optimized.

For those of ordinary skill in the art to which the present invention pertains, various substitutions, modifications and changes are possible within the scope of the present invention without departing from the technical spirit of the present invention. is not limited by

100: timing controller 200: PMIC
300: gate driver 400: data driver
500: panel 600: touch sensing unit
610: touch driving circuit 620: touch controller

Claims (12)

In the touch sensing driving circuit in which the gate driving unit 300 for displaying an image is operated during the display driving time TD and the touch sensing unit 600 sensing a touch input is operated during the touch sensing time TS,
a touch driving circuit (TPIC) 610 receiving a blank reset signal BRST transmitted from the timing controller 100 to the gate driving unit 300 ; and
and a touch controller (MCU) 620 that inverts the blank reset signal BRST transmitted from the timing controller 100 to the touch driving circuit 610 and uses it as a touch synchronization signal Tsync,
The touch synchronization signal Tsync has a falling time T2 delayed for a first time G1 from the rising time T1 of the blank reset signal BRST.
According to claim 1,
The touch controller 620,
an inverter 622 for logically inverting and outputting the blank reset signal BRST;
including a buffer 624 for delaying the output signal of the inverter for a predetermined time
Touch sensing driving circuit.
3. The method of claim 2,
The touch controller (MCU) is a touch sensing driving circuit including a plurality of buffers connected in series.
According to claim 1,
A gate driver 300 including a plurality of GIP blocks for dividing the gate lines of the panel for a touch display 500 into a plurality of blocks and respectively driving the plurality of blocks in a plurality of display driving periods TD;
and a timing controller 100 that generates and outputs the blank reset signal BRST and does not output the touch synchronization signal Tsync.
Touch sensing driving circuit.
According to claim 1,
Further comprising a panel 500 including a plurality of touch electrode rows included in the pixel array,
The panel 500,
a plurality of touch electrodes TE arranged in the longitudinal direction of the data line;
and a plurality of signal lines TL individually connected to the plurality of touch electrodes TE and connected to the touch controller 620 .
Touch sensing driving circuit.
6. The method of claim 5,
The touch driving circuit 610,
A common voltage Vcom is provided to the plurality of touch electrodes TE during the display driving time TD based on the blank reset signal BRST, and the plurality of touch electrodes during the touch sensing time TS (TE) to provide a touch drive signal (Vtouch)
Touch sensing driving circuit.
6. The method of claim 5,
The touch controller 620,
receiving a feedback signal for a touch driving signal Vtouch provided to the plurality of touch electrodes TE during the touch sensing time TS through the plurality of signal lines TL;
Sensing a change in self-capacitance of the touch electrode TE through differential amplification of the touch driving signal Vtouch and the feedback signal to calculate touch coordinate information
Touch sensing driving circuit.
In the touch sensing driving circuit that operates by dividing the display driving time (TD) and the touch sensing time (TS) based on the touch synchronization signal (Tsync),
a data driver 400 for charging a data voltage to the pixel array of the panel 500 during the display driving time TD;
a touch sensing unit 600 for sensing touch inputs on a plurality of touch electrodes TE built into the panel 500 during the touch sensing time TS; and
a timing controller 100 for providing a blank reset signal BRST used to generate the touch synchronization signal Tsync to the data driver 400 and the touch sensing unit 600;
The touch sensing unit 600,
a touch driving circuit 610 for providing different voltages to the touch electrode TE during the display driving time TD and the touch sensing time TS based on the blank reset signal BRST;
and a touch controller 620 that generates and uses the touch synchronization signal Tsync obtained by inverting the blank reset signal BRST, and calculates touch coordinate information on the touch electrode TE.
Touch sensing driving circuit.
9. The method of claim 8,
The touch controller 620,
an inverter 622 for logically inverting and outputting the blank reset signal BRST;
including a buffer 624 for delaying the output signal of the inverter for a predetermined time
Touch sensing driving circuit.
10. The method of claim 9,
The minimum time G1 between the rising time of the blank reset signal BRST and the falling time of the touch sync signal Tsync is the falling time of the blank reset signal BRST and the rising time of the touch sync signal Tsync. equal to the minimum time between times (G2)
Touch sensing driving circuit. According to claim 1,
A falling time T3 of the blank reset signal BRST and a rising time T4 of the touch synchronization signal Tsync have an interval of a second time G2.
According to claim 1,
The display driving time TD is from a rising time T0 of the touch sync signal Tsync to a rising time T1 of the blank reset signal BRST, and the touch sensing time TS is the touch sync signal A touch sensing driving circuit that is from a polling time T2 of (Tsync) to a polling time T3 of the blank reset signal BRST.

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