KR101108703B1 - A touch screen device, a driving device and a driving method for a touch panel - Google Patents

Abstract

Disclosed are a touch screen device and a method of driving a touch panel to which a direct sequence spread spectrum technology is applied. The touch panel includes a plurality of operation signal lines, a plurality of detection signal lines insulated from the plurality of operation signal lines, and a plurality of node capacitors formed by the corresponding operation signal lines and the corresponding detection signal lines, respectively. In order to drive the touch panel, an on / off operation of a plurality of driving switches electrically connected to the operation signal line or the detection signal line is selectively driven in a first driving mode or a second driving mode. In this case, the first driving mode and the second driving mode are arranged in a direct sequence.
By driving the touch panel by applying a direct sequence spreading technique as described above, EMI generated during operation of the touch screen device can be reduced and malfunction of the touch screen device can be prevented by external noise.

Description

A touch screen device, a driving device and a driving method for a touch panel}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch screen device, a drive device and a drive method of the touch panel, and more particularly, to a touch screen device, a drive device and a drive method of reducing the emission of electromagnetic interference (EMI).

Display devices such as liquid crystal displays, organic light emitting displays, portable transmission devices, and other information processing devices perform functions using various input devices. Recently, as such an input device, a touch screen device is widely used for a mobile phone, a smart phone, a palm-size PC, an automated teller machine (ATM) device, and the like.

The touch screen device touches a finger or a touch pen (stylus) on the screen to write a character, draw a picture, and execute an icon to execute a desired command.

Since the touch screen device is generally installed on a display device such as a liquid crystal display device and used as an input means of the display device, the display device malfunctions due to EMI emission from the touch screen device or touched by an external device such as a display device. There was a problem that the screen device malfunctions.

The present invention is to provide a touch screen device, a driving device of the touch panel and a driving method for reducing the EMI emission to solve such problems.

Touch screen device according to a feature of the present invention

A touch panel including a plurality of operation signal lines, a plurality of sensing signal lines insulated from the plurality of operating signal lines, and a plurality of node capacitors respectively formed by corresponding operation signal lines and sensing signal lines; A driving circuit electrically connected to the plurality of operation signal lines and configured to apply a driving waveform of a first mode or a driving waveform of a second mode to at least one of the plurality of operation signal lines; A sensing circuit electrically connected to the plurality of sensing signal lines and measuring capacitance of the node capacitor; And arranging the first switch control signal and the second switch control signal in one sequence and outputting the first switch control signal and the second switch control signal to the driving circuit so that the driving circuit outputs the driving waveform of the first mode and the driving waveform of the second mode in the first sequence. It includes a timing controller to make.

The driving circuit may include a plurality of driving switches, and the plurality of driving switches may be selectively selected into a first operation mode corresponding to the first switch control signal or a second operation mode corresponding to the second switch control signal. It can work.

Driving device for a touch panel according to a feature of the present invention

A driving device for driving a touch panel including a plurality of operation signal lines, a plurality of sensing signal lines insulated from the plurality of operating signal lines, and a plurality of node capacitors respectively formed by corresponding operation signal lines and sensing signal lines,

A driving circuit electrically connected to the plurality of operation signal lines and configured to apply a driving waveform of a first mode or a driving waveform of a second mode to a first sequence to at least one of the plurality of operation signal lines in a first sequence; And a sensing circuit electrically connected to the plurality of sensing signal lines and measuring capacitance of the node capacitor.

The driving method of the touch panel according to the characteristics of the present invention

A method of driving a touch panel comprising a plurality of operation signal lines, a plurality of sensing signal lines insulated from the plurality of operating signal lines, and a plurality of node capacitors respectively formed by corresponding operation signal lines and sensing signal lines,

The on / off operation of the plurality of drive switches electrically connected to the operation signal line or the detection signal line is selectively driven in a first driving mode or a second driving mode, wherein the first driving mode and the second driving mode are selected from the first driving mode and the second driving mode. It is arranged in 1 sequence.

In this case, an on / off operation sequence of the plurality of driving switches operating in the first operation mode and an on / off operation sequence of the plurality of driving switches operating in the second operation mode may be different.

The length of the on / off section of the plurality of drive switches operating in the first operation mode may be different from the length of the on / off section of the plurality of driving switches operating in the second operation mode.

According to the present invention, direct sequence spread spectrum (DSSS) technology is applied to a driving device of a touch screen device to reduce EMI generated when the touch screen device is operated and to prevent the touch screen device from malfunctioning due to external noise.

1 is a view showing a touch screen device according to an embodiment of the present invention.
2 is a diagram illustrating a driving circuit and a sensing circuit according to a first embodiment of the present invention.
3 to 9 are diagrams showing a driving method according to the first embodiment of the present invention.
10 is a view showing the characteristics of the low pass filter according to the first embodiment of the present invention.
11 is a view showing a driving circuit and a sensing circuit according to a second embodiment of the present invention.
12 and 13 illustrate a driving method according to a second embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The terms used below are merely for referring to specific embodiments, and are not intended to limit the present invention. Also, the singular forms used below include the plural forms unless the phrases clearly indicate the opposite meanings.

An embodiment of the present invention described below uses spread spectrum technology used in the wireless communication technology field to suppress EMI emission of a touch screen device. Spread spectrum technology is a technique for transmitting information using a bandwidth wider than the theoretical bandwidth required for transmitting specific information, and is mainly used to improve error efficiency or signal-to-noise ratio (S / N).

In an embodiment of the present invention, such a spread spectrum technology is applied to a system such as a touch screen device so that the system is less affected by ambient noise or reduces EMI generated during system operation.

In order to apply the spread spectrum technology to the touch screen device, the operating frequency must be continuously changed without fixing the spread spectrum technology. Such spread spectrum technology can be classified into the following three types.

First, as a method of varying the frequency of an oscillator in real time, a technique of giving a slight frequency jitter to the main clock of a computer CPU corresponds to this.

Second, as a method of selecting and transmitting a plurality of oscillator frequencies in real time, a frequency hopping technique corresponds to this.

Third, a direct sequence spread spectrum technique, which is referred to as a DSSS technique, is applied as a method of applying a manipulation to a digital signal before being transmitted by radio waves so that the frequency is not concentrated on a specific frequency.

An embodiment of the present invention is to apply the direct sequence spread spectrum (DSSS) technology of the spread spectrum technology to the touch screen device, to reduce the EMI generated during the operation of the touch screen device and to prevent the system from malfunctioning due to ambient noise It is for.

In general, a touch screen device may be classified into a resistive type and a capacitive type according to a method of sensing a touch.

The resistive touch screen device has a structure in which a resistive material is coated on a glass or transparent plastic plate and a polyester film is covered thereon. The resistive touch screen device detects a touch point by detecting a change in a resistance value that changes when the screen is touched.

The capacitive touch screen device forms electrodes on both sides or one side of glass or transparent plastic, applies a voltage between the two electrodes, and analyzes the amount of capacitance change between two electrodes that changes when an object such as a finger contacts the screen. Detect touch points.

Hereinafter, a capacitive touch screen device will be described as an example of the touch screen device, but the present invention is not limited thereto and may be applied to other touch screen devices. In addition, although the present invention describes a touch screen device as an example, the idea applied to the present invention can be applied to other devices.

1 illustrates a touch screen device according to an embodiment of the present invention.

As shown in FIG. 1, a touch screen device according to an embodiment of the present invention includes a touch panel 100, a driving circuit 200, a sensing circuit 300, and a timing controller 400.

The touch panel 100 includes a plurality of operation signal lines X1, X2, X3, .. Xn and a plurality of sensing signal lines Y1, Y2, Y3,... In FIG. 1, the operation signal lines and the detection signal lines are respectively indicated by lines for convenience, but are actually implemented as electrode patterns. In the present specification, the sensing signal line may be used interchangeably with terms such as sensing line, sensing line, sensing electrode, and the like, and the operation signal line may be mixed with terms such as operating line, operating line, and operating electrode. In addition, in FIG. 1, the plurality of operation signal lines and the plurality of detection signal lines are shown to cross each other by being insulated from each other. However, the present invention is not limited thereto, and the operation signal lines and the detection signal lines may not cross each other.

The sensing node 110 representing the touch point is defined by one sensing signal line and one operation signal line, and each sensing node 110 includes a node capacitor 112. The node capacitor 112 is formed by an operation signal line and a detection signal line that are insulated from and separated from each other. In FIG. 1, the capacitance of the node capacitor 112 formed by the i-th operation signal line and the j-th detection signal line is denoted by Cij.

The driving circuit 200 is electrically connected to the plurality of operation signal lines X1, X2, X3, .. Xn, and applies driving waveforms to the plurality of operation signal lines sequentially or simultaneously. At this time, the driving waveform is made up of a combination of a positive power supply voltage (or negative power supply voltage) and ground voltage as described later, the specific drive waveform is the on / off operation sequence or operation time of the drive switch of the drive circuit 200 Determined by The driving circuit 200 according to an embodiment of the present invention uses a plurality of operation signal lines X1, X2, and X3 in a predetermined sequence using two modes of operating waveforms (ie, a driving waveform of the first mode and a driving waveform of the second mode). , .. Xn).

The sensing circuit 300 is electrically connected to the plurality of sensing signal lines Y1, Y2, Y3, ... Ym, and measures the capacitance Cij of the node capacitor 112 corresponding to the sensing signal line to which a driving waveform is applied. do. At this time, the capacitance (Cij) measurement of each node capacitor 112 is implemented by the operation of the sensing switch of the sensing circuit 300, according to the embodiment of the present invention according to the mode of the driving waveform applied to the operation signal line sensing circuit The sensing switch of 300 is also operated differently.

The timing controller 400 outputs the driving switch control signals Sx1 and Sx2 and the sensing switch control signals Sy1 and Sy2 to the driving circuit 200 and the sensing circuit 300, respectively, to drive the driving switches of the driving circuit 200. And control the on / off operation of the sensing switch of the sensing circuit 300. In this case, according to an exemplary embodiment of the present invention, the timing controller 400 operates one of the driving switch control signals Sx1 and Sx2 and the sensing switch control signal to operate the touch panel 200 in one of two modes. One control signal of Sy1 and Sy2 is output to the driving circuit 200 and the sensing circuit 300, respectively. Hereinafter, for convenience of description, the first operation switch control signal Sx1 and the first detection switch control signal Sy1 will be referred to as a "first switch control signal", and the second operation switch control signal Sx2 and the second operation switch will be described. The sensing switch control signal Sy2 is referred to as a "second switch control signal".

That is, when operating the touch panel 100 in the first mode, the timing controller 400 outputs the first switch control signal so that the driving circuit 200 outputs the driving waveform in the first mode. In the case of operating 100 in the second mode, the second switch control signal is output so that the driving circuit 200 outputs the driving waveform of the second mode.

At this time, according to an exemplary embodiment of the present invention, the timing controller 400 outputs the first switch control signal or the second switch control signal in a predetermined sequence so that the driving circuit 200 generates the first waveform driving waveform or the first mode in the predetermined sequence. The driving waveforms of the two modes are output to the plurality of operation signal lines X1, X2, X3, .. Xn.

Next, the driving circuit 200 and the sensing circuit 300 according to the first embodiment of the present invention will be described in more detail with reference to FIG. 2.

In FIG. 2, only the driving circuit 200 and the sensing circuit 300 connected to the i-th operation signal line Xi and the j-th detection signal line Yj are shown for convenience, but in practice, n operation signal lines and m detection signal lines are illustrated. The driving circuit 200 and the sensing circuit 300 are electrically connected to each other.

The driving circuit 200 includes a positive power supply voltage VDD, a negative power supply voltage (-VDD), and first to third driving switches S1, S2, and S3, and is an end of the node capacitor 112. The driving waveform of the first mode and the driving waveform of the second mode are output to the signal line Xi in a predetermined sequence.

In FIG. 2, the first driving switch S1 is electrically connected between the positive power supply voltage VDD and the operation signal line Xi which is one end of the node capacitor 112, and the second driving switch S2 is connected to the ground and the node. The third driving switch S3 is electrically connected between one end of the capacitor 112 and the third driving switch S3 is electrically connected between the negative power supply voltage -VDD and one end of the node capacitor 112.

According to the first embodiment of the present invention, according to the on / off operation of the first driving switch S1, the second driving switch S2, and the third driving switch S3, the positive power supply voltage VDD and the ground The driving waveform of the first mode composed of the combination of the voltages or the driving waveform of the second mode composed of the combination of the negative power supply voltage (-VDD) and the ground voltage is output to the operation signal line Xi.

The sensing circuit 300 includes first and second sensing switches S4 and S5, an integration capacitor 310, and an amplifier 320.

The first sensing switch S4 is electrically connected between the sensing signal line Yj, which is the other end of the node capacitor 112, and the ground.

The amplifier 320 is a differential amplifier. The inverting terminal is electrically connected to the sensing signal line Yj, which is the other end of the node capacitor, and the non-inverting terminal is grounded. Hereinafter, a typical operational amplifier (OP AMP) will be described as an example of the amplifier 320. However, the present invention is not limited thereto, and other differential amplifiers may be used.

The integration capacitor 310 is electrically connected between the inverting terminal and the output terminal of the operational amplifier 320. That is, the integrating capacitor 310 plays a role of negative feedback from the output of the operational amplifier 320 to the input of the operational amplifier 320.

The second sensing switch S5 is electrically connected between the other end of the node capacitor 112 and the integrating capacitor 310 (that is, the inverting terminal of the operational amplifier 320), and the voltage charged in the node capacitor 112 is It serves to switch what is delivered to the integral capacitor.

According to an embodiment of the present invention, a voltage proportional to the product of the capacitance Cij of the node capacitor and the number of charge / discharge cycles in response to the charge / discharge operation of the node capacitor 112 at both ends of the integration capacitor 310 as will be described later. Is charged.

Next, a method of driving a touch screen device according to a first embodiment of the present invention will be described with reference to FIGS. 3 to 9.

The driving method of the touch screen device according to the first embodiment of the present invention includes a first operation mode (hereinafter referred to as a 'first charge and discharge operation mode') and a second operation mode (hereinafter referred to as a 'second charge and discharge operation'). Drive mode ").

First, the charging / discharging operation of the first operation mode will be described with reference to FIGS. 3 to 5.

According to the first operation mode, the third operation switch S3 maintains the off state, and the node capacitor 112 is charged or discharged according to the on / off operation of the other switches S1, S2, S4, and S5.

Referring to the charging operation of the node capacitor 112, the first driving switch S1 and the first sensing switch S4 are turned on, and the second driving switch S2 and the second sensing switch S5 are turned off. In this case, as shown in FIG. 5, both ends Vx of the node capacitor 112 are charged with the positive power supply voltage VDD.

Then, the discharge operation of the node capacitor 112 is performed. As shown in FIG. 4, the first driving switch S1 and the first sensing switch S4 are turned off, and the second driving switch S2 and the second driving switch S2 and the second sensing switch S4 are turned off. The sensing switch S5 is turned on. In this case, both ends Vx of the node capacitor 112 are discharged to the ground potential, and the unit charge voltage Vd is charged (transmitted) at both ends Vy of the integration capacitor 310.

At this time, the unit charge voltage (Vd) is determined by the following equation.

Where Vd is the unit charge voltage, Cij is the capacitance of the node capacitor, Ct is the capacitance of the integrating capacitor, and VDD is the supply voltage.

According to the first operation mode, in the discharging operation of the node capacitor 112, the unit charging voltage Vd is charged at both ends of the integration capacitor 310 in proportion to the capacitance of the node capacitor 112.

In FIG. 5, "charge" and "discharge" mean charging and discharging operations of a node capacitor, respectively, and "delivery" means an operation in which a unit charging voltage is charged (transmitted) to an integrated capacitor.

Next, the charge / discharge operation in the second operation mode will be described. The operation of the switch of the second charging section is the same as in FIG. 3. In this case, as shown in FIG. 5, the VDD voltage is charged at both ends Vx of the node capacitor 112 and both ends of the integration capacitor 310. Vy is maintained at the unit charging voltage Vd.

Thereafter, the second discharge operation is started, and the operation of the switch of the second discharge section is the same as in FIG. 4. In this case, as shown in FIG. 5, both ends Vx of the node capacitor 112 are discharged to the ground potential, and the unit charging voltage Vd is further charged (transmitted) at both ends of the integration capacitor 310. The voltage Vy at both ends of the integration capacitor 310 eventually becomes 2Vd.

As described above, according to the first operation mode, the integrating capacitor 310 maintains the previous voltage during the charging operation of the node capacitor 112, and the unit charging voltage Vd is applied to the integrating capacitor 310 during the discharging operation of the node capacitor. It is additionally charged (delivered).

Next, the charging and discharging operation of the second operation mode will be described with reference to FIGS. 6 to 8.

According to the second operation mode, the first operation switch S1 maintains the off state, and the node capacitor is charged or discharged according to the on / off operation of the other switches S2, S3, S4, and S5.

Referring to the charging operation of the node capacitor 112, the third driving switch S3 and the second sensing switch S5 are turned on, and the second driving switch S2 and the first sensing switch S4 are turned off. In this case, as shown in FIG. 8, a negative voltage voltage (−VDD) is charged at both ends Vx of the node capacitor 112, and a positive unit charge voltage is provided at both ends Vy of the integration capacitor 310. Vd) is charged (delivered). At this time, the voltage Vd is determined by the above equation. According to the second operation mode, unlike the charging / discharging operation of the first mode, in the charging operation of the node capacitor 112, the unit charge voltage Vd proportional to the capacitance of the node capacitor 112 is charged in the integration capacitor 310. (Delivered).

Then, the discharge operation of the node capacitor 112 is performed. As shown in FIG. 7, the third driving switch S3 and the second sensing switch S5 are turned off, and the second driving switch S2 and the second driving switch S2 and the second sensing switch S5 are turned off. 1 Detection switch S4 is turned on. In this case, as shown in FIG. 8, both ends Vx of the node capacitor 112 are discharged to the ground potential, and the voltage Vy of both ends of the integration capacitor 310 is maintained at Vd.

In FIG. 8, "charge" and "discharge" refer to charging and discharging operations of the node capacitor, respectively, and "delivery" refers to an operation of charging (delivering) unit charging voltage to the integrating capacitor.

Next, the charge / discharge operation in the second operation mode will be described. The operation of the switch of the second charging section is the same as in FIG. 6. In this case, as shown in FIG. 8, the voltage Vx of the node capacitor 112 is charged with the -VDD voltage, and the integrating capacitor 310 is applied. Both ends Vy of Vd are further charged by Vd, and the voltage Vy of both ends of the integrating capacitor 310 is charged to 2Vd.

Subsequently, the second discharge operation is started, and the operation of the switch in the second discharge period is the same as in FIG. 7, in which case, as shown in FIG. 8, both ends Vx of the node capacitor 112 are connected to the ground potential. Is discharged to and the voltage Vy across the integration capacitor 310 is maintained at 2Vd.

As described above, according to the second operation mode, the unit charging voltage Vd is additionally charged (transmitted) to the integrating capacitor 310 during the charging operation of the node capacitor 112, and the integrating capacitor 310 during the discharging operation of the node capacitor. Maintains the previous voltage.

Next, a driving method according to a first embodiment of the present invention will be described with reference to FIG. 9.

According to the first embodiment of the present invention, it operates in two modes (first operation mode and second operation mode), and each operation mode has two phases (phase 0, phase 1). In this case, "phase 0" and "phase 1" refer to "charge operation period" and "discharge operation period" of the node capacitor, respectively.

The on / off operation of the switches corresponding to these modes and phases is summarized in the following table.

First operation mode (mode 1) Second operation mode (mode 2) phase 0 phase 1 phase 0 phase 1 ON switch S1, S5 S2, S5 S3, S5 S2, S4 OFF switch S2, S3, S5 S1, S3, S4 S1, S2, S4 S1, S3, S5 action charge Discharge + delivery Charge + Forward Discharge

As shown in Table 1, in the first operation mode (mode 1), the "transfer operation" in which the unit charge voltage is charged (transmitted) to the integrating capacitor in the state of "phase 1" (ie, the discharge operation period of the node capacitor). In the second operation mode (mode 2), the difference in that the "transfer operation" in which the unit charging voltage is charged (transferred) to the integrating capacitor is performed in the state of "phase 0" (ie, the charging operation period of the node capacitor). There is this.

As shown in FIG. 9, according to the exemplary embodiment of the present invention, the EMI is emitted from the touch screen device by driving the touch screen device by combining the first operation mode and the second operation mode in a predetermined sequence.

In FIG. 9, the first operation mode is denoted by "0", and the second operation mode is denoted by "1". According to the first embodiment of the present invention, a touch screen device is driven by combining two operation modes using a barker sequence having a direct sequence of “01001000111”. In FIG. 9, for convenience, a voltage waveform charged in an integrated capacitor in response to “01001” which is a part of the barker sequence is illustrated. However, a person skilled in the art may easily understand the voltage waveform corresponding to the entire barker sequence from FIG. 9. As shown in FIG. 9, when the touch screen device is driven by the Barker sequence, the voltage Vy charged to the integration capacitor may be irregular, as shown in FIG. 9. When the charging voltage (ie, the output voltage) is converted into the frequency domain, it can be seen that the frequency band is spread spectrum. In FIG. 9, the Barker sequence is used as a direct sequence, but the present invention is not limited thereto, and other direct sequences may be used.

Therefore, according to the first embodiment of the present invention, the spread spectrum technology is applied, so that EMI generated by the output voltage can be reduced. In addition, when the two operation modes are operated in a combination of predetermined sequences, the operation of the switches of each driving circuit and the sensing circuit is driven irregularly, so that EMI generated by the on / off operation of the switch can be reduced.

On the other hand, since the driving circuit and the sensing circuit according to the first embodiment of the present invention use a switched capacitor, it basically has the characteristics of a finite impulse response (FIR) filter. In other words, when the touch screen device is driven in "phase 0" and "phase 1" in one circuit, it operates as an FIR filter having N taps for N drivings.

Specifically, the driving circuit and the sensing circuit according to the first embodiment of the present invention operate as a low pass filter having a different frequency response according to the driving frequency N. As shown in FIG. It can be seen that the characteristics of the filter are excellent.

Therefore, according to the first embodiment of the present invention, it is possible to prevent the touch screen device from malfunctioning due to noise generated by an external device such as a display device.

According to the first exemplary embodiment of the present invention described above, the on / off order of the switches is different for each operation mode when the first operation mode and the second operation mode are operated, but the present invention is not limited thereto. As in the second embodiment of the present invention, the on / off operation order of the switches may be the same for each mode, and only the on / off period may be set differently.

Next, the driving circuit 500 and the sensing circuit 300 according to the second embodiment of the present invention will be described in more detail with reference to FIG. 11.

As shown in FIG. 11, the driving circuit 500 according to the second embodiment of the present invention includes a positive power supply voltage VDD and first and second driving switches S10 and S20.

In FIG. 11, the first driving switch S10 is electrically connected between the positive power supply voltage VDD and the operation signal line Xi which is one end of the node capacitor 112, and the second driving switch S2 is connected to the ground and the node. It is electrically connected between one end of the capacitor 112. According to the on / off operation of the first driving switch S10 and the second driving switch S20, a driving waveform formed of a combination of a positive power supply voltage VDD and a ground voltage is output to the operation signal line Xi. In this case, according to the second exemplary embodiment of the present invention, the operation signal line Xi is combined by varying the on / off period of the driving switching by combining the driving waveform of the third mode having the width of the driving waveform and the square waveform of the fourth mode in a predetermined sequence. )

Since the sensing circuit 300 performs the same configuration as the sensing circuit 300 shown in FIG. 2 except for the reference numerals, redundant description will be omitted.

Next, a driving method of a touch screen device according to a second embodiment of the present invention will be described with reference to FIGS. 12 and 13.

According to the second embodiment of the present invention, the touch screen device is driven by the combination of the third operation mode (mode 3) and the fourth operation mode (mode 4). The charge / discharge operation of the third operation mode and the fourth operation mode is driven in the same manner as the first operation mode according to the first embodiment of the present invention. That is, in the third operation mode and the fourth operation mode, the on / off order of each driving and sensing switch is driven in the same manner, and the unit charge voltage is charged (transmitted) to the integrating capacitor when the node capacitor is discharged. 12 and 13, "charging" means a charging operation section of the node capacitor, and "delivery" means a section in which the unit charging voltage is transferred to the integrating capacitor (that is, the discharging operation section of the node capacitor).

12 and 13, according to the second embodiment of the present invention, the charge / discharge section L1 of the third operation mode is set longer than the charge / discharge section L2 of the fourth operation mode, and the third The touch screen device is driven by combining the operation mode and the fourth operation mode in a predetermined sequence. Then, as shown in FIG. 13, it can be seen that the voltage in which the frequency band is spread is charged in the integrating capacitor.

Therefore, like the first embodiment, the second embodiment of the present invention can reduce the EMI generated by the output voltage.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications, and variations will readily occur to those skilled in the art without departing from the spirit and scope of the invention. Therefore, it should be understood that the disclosed embodiments are to be considered in an illustrative rather than a restrictive sense, and that the true scope of the invention is indicated by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof, .

100: touch panel 200: driving circuit
300: detection circuit 400: timing controller
112: node capacitor 310: integral capacitor
320: operational amplifier S1, S2, S3, S10, S20: drive switch
S4, S5, S30, S40: Sense Switch

Claims (19)

A touch panel including a plurality of operation signal lines, a plurality of sensing signal lines insulated from the plurality of operating signal lines, and a plurality of node capacitors respectively formed by corresponding operation signal lines and sensing signal lines;
A driving circuit electrically connected to the plurality of operation signal lines and configured to apply a driving waveform of a first mode or a driving waveform of a second mode to at least one of the plurality of operation signal lines;
A sensing circuit electrically connected to the plurality of sensing signal lines and measuring capacitance of the node capacitor; And
Arranging a first switch control signal and a second switch control signal in one sequence and outputting them to the driving circuit so that the driving circuit outputs the driving waveform of the first mode and the driving waveform of the second mode in the first sequence; Touch screen device comprising a timing controller. The method of claim 1,
The driving circuit
And a plurality of driving switches, wherein the plurality of driving switches selectively operate in a first operation mode corresponding to the first switch control signal or in a second operation mode corresponding to the second switch control signal. Touch screen device. The method of claim 2,
And an on / off operation sequence of the plurality of drive switches operating in the first operation mode and an on / off operation sequence of the plurality of drive switches operating in the second operation mode. The method of claim 2,
The length of the on / off section of the plurality of drive switches operating in the first operation mode and the length of the on / off section of the plurality of drive switches operating in the second operation mode is different. . The method according to any one of claims 1 to 4,
The first sequence is a touch screen device, characterized in that the Barker sequence. A driving apparatus for driving a touch panel comprising a plurality of operation signal lines, a plurality of sensing signal lines insulated from the plurality of operating signal lines, and a plurality of node capacitors respectively formed by corresponding operation signal lines and sensing signal lines. ,
A driving circuit electrically connected to the plurality of operation signal lines and configured to apply a driving waveform of a first mode or a driving waveform of a second mode to a first sequence to at least one of the plurality of operation signal lines in a first sequence; And
And a sensing circuit electrically connected to the plurality of sensing signal lines and measuring capacitance of the node capacitor. The method of claim 6,
The driving circuit
A first driving switch electrically connected between one end of the node capacitor and a first voltage;
A second driving switch electrically connected between one end of the node capacitor and a second voltage, and
And a third driving switch electrically connected between one end of the node capacitor and a third voltage having a polarity opposite to the first voltage. The method of claim 7, wherein
The sensing circuit
A first sense switch electrically connected between the other end of the node capacitor and a fourth voltage;
An integrating capacitor electrically connected to the other end of the node capacitor and configured to receive and charge a unit charge voltage corresponding to the voltage charged in the node capacitor; And
And a second sensing switch electrically connected between the other end of the node capacitor and the integrating capacitor and switching the unit charge voltage from being transferred to the integrating capacitor. The method of claim 8,
And wherein the second voltage and the fourth voltage are ground voltages. 10. The method of claim 9,
The sensing circuit
And a differential amplifier having one end and a ground connected to the first input terminal and the second input terminal, respectively, and the other end of the integrated capacitor connected to the output terminal. The method according to any one of claims 8 to 10,
The first to third driving switches and the first and second sensing switches may be selectively configured as a first operation mode corresponding to the square waveform of the first mode or a second operation mode corresponding to the driving waveform of the second mode. Driving device for a touch panel, characterized in that the operation. The method of claim 11,
The first to third driving switches operating in the first operation mode, the on / off operation sequence of the first and second sensing switches, and the first to third driving switches operating in the second operation mode, and The on / off operation sequence of the first and second sensing switches is different. The method of claim 12,
In the first operation mode, the unit charge voltage is transferred to the integrating capacitor when the node capacitor is discharged.
And the unit charging voltage is transferred to the integrating capacitor when the node capacitor is charged in the second operation mode. The method of claim 6,
The driving circuit
A first driving switch electrically connected between one end of the node capacitor and a first voltage, and a second driving switch electrically connected between one end of the node capacitor and a second voltage,
The sensing circuit
A first sense switch electrically connected between the other end of the node capacitor and a third voltage;
An integrating capacitor electrically connected to the other end of the node capacitor and configured to receive and charge a unit charge voltage corresponding to the voltage charged in the node capacitor;
A second sensing switch electrically connected between the other end of the node capacitor and the integrating capacitor, the second sensing switch switching the transfer of charge charged in the integrating capacitor to the integrating capacitor; And
And a differential amplifier having one end of the integration capacitor and the third voltage connected to a first input terminal and a second input terminal, respectively, and the other end of the integration capacitor connected to an output terminal. The method of claim 14,
The first and second driving switches and the first and second sensing switches may be selectively configured as a first operation mode corresponding to the square waveform of the first mode or a second operation mode corresponding to the driving waveform of the second mode. Driving device for a touch panel, characterized in that the operation. 16. The method of claim 15,
A length of an on / off section of the first and second driving switches, the first and second sensing switches operating in the first operation mode, and the first and second driving switches operating in the second operation mode, The length of the on / off section of the first, second sensing switch is a drive device of the touch panel, characterized in that different. A method of driving a touch panel comprising a plurality of operation signal lines, a plurality of detection signal lines insulated from the plurality of operation signal lines, and a plurality of node capacitors respectively formed by corresponding operation signal lines and the detection signal lines.
The on / off operation of the plurality of drive switches electrically connected to the operation signal line or the detection signal line is selectively driven in a first driving mode or a second driving mode, wherein the first driving mode and the second driving mode are configured to be the first driving mode. Method of driving a touch panel, characterized in that arranged in one sequence The method of claim 17,
The on / off operation sequence of the plurality of drive switches operating in the first operation mode and the on / off operation sequence of the plurality of drive switches operating in the second operation mode are different. . The method of claim 17,
The length of the on / off section of the plurality of driving switches operating in the first operation mode and the length of the on / off section of the plurality of driving switches operating in the second operation mode is different. Driving method.

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