KR101182399B1 - 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 autocorrelation technology is applied. The driving circuit corresponds to each driving waveform in which the driving waveform of the first mode for charging the node capacitor with the positive voltage and the driving waveform of the second mode for charging the node capacitor with the negative voltage are combined in a predetermined binary sequence. Output to the operation signal line. The sensing circuit is electrically connected to the plurality of sensing signal lines, and measures the sensing voltage transferred from the plurality of node capacitors to the one integration capacitor. The sensing recognition unit adds or subtracts a sensing voltage measured by the sensing circuit in a predetermined binary sequence for each driving time, thereby measuring capacitance corresponding to each node capacitor.
By applying the autocorrelation technology generally used in the communication system to drive the touch screen device, it is possible to shorten the driving time and to prevent the touch screen device from malfunctioning due to external noise.

Description

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

The present invention relates to a touch screen device, a driving device and a driving method of the touch panel, and more particularly, to a touch screen device, a driving device and a driving method of the touch panel that can reduce the driving time.

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.

Such touch screen devices 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 resistive touch screen device has a disadvantage in that it cannot detect when the pressure is weak.

On the other hand, in the capacitive touch screen device, electrodes are formed on both surfaces or one surface of glass or transparent plastic, and a voltage is applied between the two electrodes, and then the amount of capacitance change between the two electrodes changes when an object such as a finger contacts the screen. Analyze and detect touch points.

In order to detect a touch point in a capacitive touch screen device, a driving device for measuring a capacitance formed between two electrodes and sensing a change amount of capacitance is required. The driving device includes a driving circuit for driving each node capacitor and a sensing circuit for sensing an amount of change in capacitance of the node capacitor.

According to the driving device of the conventional touch panel, since each node capacitor is sequentially driven and then the amount of change in capacitance of each node capacitor is sequentially measured, there is a long driving time for detecting a touch point. In addition, since touch panels used in mobile phones and the like are formed on display devices such as LCDs, there has been a problem of malfunction due to external noise.

The present invention is to provide a touch screen device, a drive device and a drive method of the touch panel that can reduce the driving time and prevent the malfunction due to external noise.

Touch screen device according to a feature of the present invention

A touch panel including 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 corresponding operation signal lines and corresponding detection signal lines, respectively; A corresponding operation waveform in which a driving waveform of a first mode for charging the node capacitor with a positive voltage and a driving waveform of a second mode for charging the node capacitor with a negative voltage are combined in a predetermined binary sequence A drive circuit output to a signal line; A sensing circuit electrically connected to the plurality of sensing signal lines, the sensing circuit measuring a sensing voltage transmitted from one node capacitor to one integration capacitor electrically connected to a corresponding sensing signal line; And a sensing recognition unit for measuring capacitance corresponding to each node capacitor by performing an addition or subtraction operation of the sensing voltage measured by the sensing circuit for each driving time in a predetermined binary sequence.

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

A driving apparatus 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 operating signal lines and corresponding sensing signal lines. Each driving waveform in which a driving waveform of a first mode for charging the node capacitor with a positive voltage and a driving waveform of a second mode for charging the node capacitor with a negative voltage are combined in a predetermined binary sequence. A driving circuit for outputting to an operation signal line; A sensing circuit electrically connected to the plurality of sensing signal lines, the sensing circuit measuring a sensing voltage transmitted from one node capacitor to one integration capacitor electrically connected to a corresponding sensing signal line; And a sensing recognition unit for measuring capacitance corresponding to each node capacitor by performing an addition or subtraction operation of the sensing voltage measured by the sensing circuit for each driving time in a predetermined binary sequence.

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

A method of driving a touch panel including 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 corresponding operation signal lines and corresponding detection signal lines, respectively.

A corresponding operation waveform in which a driving waveform of a first mode for charging the node capacitor with a positive voltage and a driving waveform of a second mode for charging the node capacitor with a negative voltage are combined in a predetermined binary sequence Outputting to a signal line; Measuring a sensing voltage transmitted to each integrated capacitor from each of the plurality of node capacitors electrically connected to the corresponding sensing signal lines for each driving time point; And adding or subtracting the sensed voltage measured for each driving time in a predetermined binary sequence, thereby measuring capacitance corresponding to each node capacitor.

According to the present invention, autocorrelation used in a communication system is applied to a driving device of a touch screen device, thereby reducing driving time of the touch screen device and preventing malfunction of the touch screen device 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 an embodiment of the present invention.
3 to 7 are diagrams illustrating a driving method of each unit driving unit according to an exemplary embodiment of the present invention.
8A to 8D are views illustrating a method of driving a touch screen device according to an 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 terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. Also, the singular forms as used below include plural forms unless the phrases expressly have the opposite meaning.

According to an embodiment of the present invention described below, by applying autocorrelation generally used in a communication system to drive the touch screen device, it is possible to reduce the influence of external noise and to shorten the driving time.

In general, autocorrelation in signal transmission indicates a correlation between a signal sent from a transmitter and a signal received at a receiver. Since a communication system using such autocorrelation can know the signal characteristics at the transmitting side in advance, there is a feature that can reduce the influence of external noise coming between the transmitting side and the receiving side. Specifically, the transmitting side transmits a plurality of transmission signals having binary sequences of 1 or 0 (binary sequences of different transmission signals have orthogonality), and the receiving side performs autocorrelation using the same binary sequence of the transmitting binary sequence. In this way, the influence of external noise or other transmission signals can be eliminated.

In the touch screen device according to the embodiment of the present invention described below, the driving circuit for driving each node capacitor is simultaneously driven using a binary sequence, and the sensing voltage delivered by the plurality of node capacitors is binary at each driving time point. By operating in a sequence, the driving time can be reduced while eliminating the influence of external noise.

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, a timing controller 400, and a sensing recognition unit 500. Include.

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. Hereinafter, the capacitance of the node capacitor will be referred to simply as "node capacitance".

The driving circuit 200 is electrically connected to the plurality of operation signal lines X1, X2, X3, .. Xn, and simultaneously applies driving waveforms to the plurality of operation signal lines. In this case, the driving waveform is a combination of a positive power supply voltage, a negative power supply voltage and a ground voltage as described below, and the specific driving waveform is determined by the on / off operation sequence of the drive switch of the driving circuit 200. In the embodiments of the present invention described below, "applying" a driving waveform to a plurality of operating signal lines at the same time does not mean that the driving waveforms are simultaneously applied to the plurality of operating signal lines at the exact same time point. The concept includes applying with a time difference.

The driving circuit 200 according to the embodiment of the present invention has a driving waveform of a first mode for charging a positive voltage to the node capacitor 112 and a second mode for charging a negative voltage to the node capacitor 112. Each of the drive waveforms in which the drive waveforms are combined in a predetermined sequence is simultaneously output to the corresponding operation signal lines X1, X2, X3, .. Xn. In this case, when the driving waveforms of the first mode and the driving waveforms of the second mode are denoted as "1" and "0", respectively, the driving waveforms of the first mode and the second mode are simultaneously displayed on the plurality of operation signal lines X1, X2, X3, .. Xn at an arbitrary driving point. The output driving waveform forms a predetermined binary sequence (BS).

In this case, the binary sequences applied to the operation signal lines at different driving points may be formed of different binary sequences having orthogonality. For example, a binary sequence BS1 simultaneously applied to a plurality of operation signal lines at a driving point of t1 and a binary sequence BS2 simultaneously applied to a plurality of operation signal lines at a driving point of t2 have orthogonality. Here, the number of driving time points of the driving circuit is set equal to the number of operation signal lines X1, X2, X3, .. Xn to which the driving waveforms are simultaneously applied.

The sensing circuit 300 is electrically connected to the plurality of sensing signal lines Y1, Y2, Y3, ... Ym, and the capacitances C1j, of the plurality of node capacitors 112 corresponding to the sensing signal lines to which a driving waveform is applied. The sensing voltage SV transmitted by C2j, C3j, ..., Cnj) is measured. At this time, the sensing voltage is a value of adding (+) or subtracting (-) the capacitances C1j, C2j, C3j, ..., Cnj of the plurality of node capacitors corresponding to each sensing signal line Yj to a predetermined sequence. Proportional.

The timing controller 400 outputs a driving switch control signal and a sensing switch control signal to the driving circuit 200 and the sensing circuit 300, respectively, so that the driving switch of the driving circuit 200 and the sensing switch of the sensing circuit 300 are controlled. Control on / off operation.

The sensing recognizer 500 stores the sensing voltage (corresponding to the calculated multi-node capacitance value) in the memory (not shown) detected by the sensing circuit 300 at each driving time point, and then detects each sensing time point. By adding or subtracting the voltages SV1, SV2, ..., SVn in a predetermined sequence, the capacitance corresponding to each node capacitor can be measured. In this case, the combination sequence of the "add" operation and the "subtraction" operation performed by the sensing recognizer 500 may be set to be the same as the sequence of the driving waveform applied to the corresponding operation signal line.

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

The driving circuit 200 includes a plurality of unit drivers 200a, 200b, 200c, and 200d that apply driving waveforms to corresponding node capacitors C1j, C2j, C3j, and C4j, respectively. In the embodiment of the present invention, four unit driving units are described as an example, but the number of unit driving units is not limited and may be appropriately selected within a range not exceeding the number of operation signal lines.

Each unit driver 200a, 200b, 200c, or 200d includes a positive power supply voltage VDD, a negative power supply voltage VDD, first drive switches S11, S12, S13, and S14, and a second drive switch, respectively. S21, S22, S23, and S24 and third driving switches S31, S32, S33, and S34, and applying a driving waveform and a negative voltage in a first mode to apply a positive voltage to a corresponding node capacitor. The driving waveforms in which the driving waveforms of the second mode are combined in a predetermined sequence are applied.

In this case, the sequence of the driving waveforms applied to the corresponding node capacitors by the unit driving units 200a, 200b, 200c, and 200d may be formed in different sequences having orthogonality.

In FIG. 2, the first driving switches S11, S12, S13, and S14 are electrically connected between the positive power supply voltage VDD and the operation signal lines X1, X2, X3, and X4, which are ends of the node capacitor 112. The second driving switches S21, S22, S23, and S24 are electrically connected between the ground and one end of the node capacitor 112, and the third driving switches S31, S32, S33, and S34 may have a negative power supply voltage ( -VDD) and one end of the node capacitor 112 is electrically connected.

According to an embodiment of the present invention, the first driving switch S11, S12, S13, the second driving switch S21, S22, S23, and the third driving switch S31, S32, S33 may be operated. The driving waveform of the first mode consisting of a combination of a positive power supply voltage (VDD) and a ground voltage and the driving waveform of a second mode consisting of a combination of a negative power supply voltage (-VDD) and a ground voltage are formed in a predetermined sequence. It is output to the corresponding operation signal lines X1, X2, X3, and X4.

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 each node capacitor C1j, C2j, C3j, and C4j, 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 common other end of the node capacitors C1j, C2j, C3j, and C4j and the integrating capacitor 310 (that is, the inverting terminal of the operational amplifier 320). C1j, C2j, C3j, C4j) serves to switch the transfer of the voltage corresponding to the operation value of the voltage charged in the integrated capacitor, respectively.

Next, an operation of the unit driver according to an exemplary embodiment of the present invention will be described with reference to FIGS. 3 to 7.

Hereinafter, for convenience of description, the operation of the first unit driver 200a will be described, but the other unit drivers 200b, 200c, and 200d operate in the same manner.

In the driving method of the unit driver 200a according to an exemplary embodiment of the present invention, a first driving mode for applying a positive voltage VDD to a node capacitor and a second driving mode for applying a negative power supply voltage -VDD are provided. Driven by a combination of.

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

According to the first driving mode, the third operation switch S31 maintains the off state, and the node capacitor 112 is charged or discharged according to the on / off operation of the other switches S11, S21, S4, and S5.

Referring to the charging operation of the node capacitor 112, as shown in FIG. 4, the first driving switch S11 and the first sensing switch S4 are turned on, and the second driving switch S21 and the second sensing switch are turned on. (S5) is turned off. In this case, 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. 5, the first driving switch S11 and the first sensing switch S4 are turned off, and the second driving switch S21 and the second driving switch S21 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 (1).

Where Vd is the unit charge voltage, C1j is the capacitance of the node capacitor formed by the first driving signal line and the jth sensing signal line, Ct is the capacitance of the integrating capacitor, and VDD is the power supply voltage.

According to the first driving mode, a positive power supply voltage VDD is charged at both ends of the node capacitor during the charging operation of the node capacitor 112, and at both ends of the integrating capacitor 310 during the discharging operation of the node capacitor 112. The unit charging voltage Vd proportional to the capacitance C1j of the capacitor 112 is charged.

In the embodiment of the present invention, "charge" and "discharge" refer to charging and discharging operations of the node capacitor, respectively, and "delivery" refers to an operation in which the unit charging voltage is charged (transmitted) to the integrating capacitor.

Next, the charging and discharging operation of the second driving mode will be described with reference to FIGS. 6 and 7.

According to the second driving mode, the first operation switch S11 maintains the off state, and the node capacitor 112 is charged or discharged according to the on / off operation of the other switches S21, S31, S4, and S5.

Referring to the charging operation of the node capacitor 112, as shown in FIG. 6, the third driving switch S31 and the first sensing switch S4 are turned on, and the second driving switch S21 and the second sensing switch are turned on. (S5) is turned off. In this case, both ends Vx of the FIG. Node capacitor 112 are charged with a negative power supply voltage (−VDD).

Then, the discharging operation of the node capacitor 112 is performed. As shown in FIG. 7, the third driving switch S31 and the first sensing switch S4 are turned off, and the second driving switch S21 and the second driving switch S21 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 a negative unit charge voltage Vd is charged (transmitted) at both ends Vy of the integration capacitor 310. At this time, the voltage Vd is determined by the above equation (1).

According to the second driving mode, a negative power supply voltage (-VDD) is charged at both ends of the node capacitor during the charging operation of the node capacitor 112, and at both ends of the integral capacitor 310 during the discharging operation of the node capacitor 112. The negative unit charge voltage (-Vd), which is proportional to the capacitance C1j of the node capacitor 112, is charged.

Next, a method of driving a touch screen device according to an embodiment of the present invention will be described with reference to FIGS. 8A to 8D.

According to the exemplary embodiment of the present invention, each unit driver 200a, 200b, 200c, or 200d drives the first driving mode and the second driving mode in a predetermined sequence. According to FIGS. 8A to 8D, a first driving mode for applying a positive power supply voltage to a node capacitor is denoted as "1", and a second driving mode for applying a negative power supply voltage to the node capacitor is denoted as "0". It was. According to an exemplary embodiment of the present invention, a driving waveform simultaneously output to a plurality of operation signal lines X1, X2, X3, and X4 at an arbitrary driving time may be represented by a predetermined binary sequence (BS). As shown in Figs. 8A to 8D, the binary sequence BS1 of the driving waveform driven by each of the unit driving units 200a, 200b, 200c, and 200d at the driving time point t1 is " 0111 " The binary sequence BS2 of the drive waveform driven by the unit driver is "1011", and the binary sequence BS3 of the drive waveform driven by each unit driver at the drive time t3 is "1101", and each of the drive sequence is driven at t4. The binary sequence BS4 of the drive waveform driven by the unit driver is " 1110 ". That is, according to the embodiment of the present invention, the binary sequence of each driving time point is the same as shifting the binary sequence of the previous driving time point to the right.

Here, the binary sequences BS1, BS2, BS3, and BS4 applied to the respective operation signal lines at different driving points may be formed of different binary sequences having orthogonality. For example, 0111, which is a binary sequence BS1 that is simultaneously applied to four operation signal lines at a driving point of t1, and 1011, which is a binary sequence BS2 that is simultaneously applied to four operation signal lines at a driving point of t2, have orthogonality. .

In addition, according to an exemplary embodiment of the present invention, the unit driver 200a is driven in the order of 0, 1, 1, 1 (the binary sequence is 0111) and the unit at the sequential driving time points t1, t2, t3, and t4. The driver 200b is driven in the order of 1, 0, 1, 1 (binary sequence is 1011), and the unit driver 200c is driven in the order of 1, 1, 0, 1 (binary sequence is 1101), The unit driver 200d is driven in the order of 1, 1, 1, 0 (the binary sequence is 1110).

As shown in FIG. 8A, the unit driver 200a, the unit driver 200b, the unit driver 200c, and the unit driver 200d are respectively driven at 0, 1, 1, and 1 at a driving time point t1. Accordingly, each node capacitor is charged with the voltages -VDD, VDD, VDD, and VDD.

At this time, the sensing voltage SV1 transferred from each node capacitor to the integration capacitor Ct at the time t = t1 is expressed by Equation 2 below.

Where k is a constant value of VDD / Ct

In addition, according to the driving method illustrated in FIGS. 8B to 8D, the sensing voltages SV2, SV3, and SV4 transferred from the node capacitors to the integrating capacitor Ct at the time points t2, t3, and t4 are represented by the following Equations 3 and 3 below. same.

As shown in Equations 2 and 3, when the sensing voltages SV1, SV2, SV3, and SV4 sensed by the sensing circuit 300 are added or subtracted in a predetermined sequence as shown in Equations 2 and 3, Likewise, capacitances C1j, C2j, C3j, and C4j of each node capacitor can be obtained.

That is, according to the exemplary embodiment of the present invention, the sensing recognizer 500 stores the sensing voltages SV1, SV2, SV3, and SV4 sensed by the sensing circuit 300 at each driving time in a memory (not shown). Then, when the sensing voltages SV1, SV2, SV3, SV4 are added or subtracted in a predetermined sequence, the capacitances C1j, C2j, C3j, and C4j of each node capacitor can be obtained as shown in Equation 4. In this case, the combination sequence of the "add" operation and the "subtraction" operation performed by the detection recognition unit 500 may be set to be the same as the sequence of the driving waveform applied to the corresponding operation signal line.

Specifically, the unit driver 200a applying the driving waveform to the operation signal line X1 is driven by a binary sequence of 0111 at each driving time, and the sensing recognition unit 500 detects the sensing voltages SV1, SV2, and SV3 detected at each driving time. , SV4) is calculated in the order of-, +, +, + (that is, the binary sequence is 0111), whereby the node capacitance C1j corresponding to the unit driver 200a is measured. In addition, the node capacitances C2j, C3j, and C4j corresponding to the other unit drivers 200b, 200c, and 200d may also have the sense voltages SV1 and SV2 in the same binary sequence as that of the driving binary sequence of the unit drivers 200b, 200c, and 200d. , SV3, SV4).

As described above, according to the exemplary embodiment of the present invention, unlike a conventional driving method in which each node capacitor is sequentially driven, and then the capacitance of each node capacitor is sequentially measured, a driving waveform having a predetermined binary sequence at an arbitrary driving time point. As a result, the driving time can be shortened by simultaneously driving a plurality of unit drivers and measuring the sensed voltage transferred from each node capacitor to one integrated capacitor and calculating the calculated voltage in the sensing unit.

In addition, according to the driving method according to an embodiment of the present invention, by measuring the node voltage by calculating the sensed voltage (ie, using autocorrelation) in the same binary sequence that is driven to the plurality of node capacitors at each driving time point Therefore, there is an advantage that the influence of external noise can be eliminated.

8A through 8D illustrate the case in which four unit driving units are driven by a binary sequence including 0111 having perfect orthogonality, but the present invention is not limited thereto. It can also be applied using binary sequences with good orthogonality, such as a Barker sequence.

In addition, when the touch screen device having n unit driving units is driven, an embodiment of the present invention may be expressed by generalizing the following Equation 5 similarly to Equations 2 and 3 below.

Here, V is a voltage transmitted and sensed by one node capacitor by a plurality of node capacitors at each driving time point, and is a matrix of n × 1, and k is a ratio of the power supply voltage VDD and the capacitance Ct of the integration capacitor. Where A is an n × n matrix of −1 and 1, and C is n × 1 corresponding to the capacitance of each node capacitor. Here, "1" in A matrix means the first driving mode (the positive power supply voltage is applied to the node capacitor), and "-1" means the second driving mode (the negative power supply voltage is applied to the node capacitor). do.

The capacitance matrix C of each node capacitor can be obtained from Equation 6 from Equation 5 below.

는 A의 역행렬의 의미한다. here,

Is the inverse of A.

Therefore, as can be seen from Equation 6, each node voltage can be obtained by calculating each sensing voltage with the same value as the sequence obtained by the inverse of the matrix A consisting of -1 and 1.

On the other hand, if each node capacitor is driven for each driving time by the matrix A satisfying the following equation (7), as described in the embodiment of the present invention, the same binary as the binary sequence driven to the plurality of node capacitors for each driving time Since each node capacitance can be measured by calculating the sense voltage in sequence (that is, using autocorrelation), there is an advantage that the influence of external noise can be eliminated.

Where n is an integer and I is a unit matrix of n × n.

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
500: detection unit 112: node capacitor
310: integral capacitor 320: operational amplifier

Claims (21)

A touch panel including 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 corresponding operation signal lines and corresponding detection signal lines, respectively;
A corresponding operation waveform in which a driving waveform of a first mode for charging the node capacitor with a positive voltage and a driving waveform of a second mode for charging the node capacitor with a negative voltage are combined in a predetermined binary sequence A drive circuit output to a signal line;
A sensing circuit electrically connected to the plurality of sensing signal lines, the sensing circuit measuring a sensing voltage transmitted from one node capacitor to one integration capacitor electrically connected to a corresponding sensing signal line; And
And a sensing recognizer configured to measure capacitance corresponding to each node capacitor by performing an addition or subtraction operation of the sensing voltage measured by the sensing circuit in a predetermined binary sequence for each driving time point. The method of claim 1,
The driving circuit includes a plurality of unit driving units for applying respective driving waveforms to corresponding operation signal lines. The method of claim 2,
And the positive voltage charged in the node capacitor and the negative voltage charged in the node capacitor are equal in magnitude. 4. The method according to any one of claims 1 to 3,
And a first binary sequence simultaneously applied to the plurality of operation signal lines at a first driving time and a second binary sequence simultaneously applied to the plurality of operation signal lines at a second driving time are orthogonal to each other. 4. The method according to any one of claims 1 to 3,
And a third binary sequence applied to the first operation signal line by a plurality of driving time points and a fourth binary sequence applied to the second operation signal line by a plurality of driving time points are orthogonal to each other. The method of claim 5,
The detection recognition unit
A touch screen device for measuring the capacitance of a corresponding node capacitor by performing an addition or subtraction operation of the sensed voltage measured by the sensing circuit for each driving time in the same sequence as the binary sequence applied for each driving time. . 4. The method according to any one of claims 1 to 3,
The sensing voltage delivered to the integrating capacitor measured by the sensing circuit is

Where V is a voltage transmitted and sensed to the integrating capacitor by a plurality of node capacitors at each driving time point, and n is a matrix of n × 1, k is a constant, and A is an n × n matrix of −1 and 1, When C satisfies the n × 1 matrix corresponding to the capacitance of each node capacitor,
The capacitance of each node capacitor is given by

(here,

Is the inverse of A)
Touch screen device, characterized in that obtained through. The method of claim 7, wherein
The matrix A is

Where n is an integer and I is a unit matrix of n × n.
Touch screen device, characterized in that to satisfy. A driving apparatus 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 operating signal lines and corresponding sensing signal lines. To
A corresponding operation waveform in which a driving waveform of a first mode for charging the node capacitor with a positive voltage and a driving waveform of a second mode for charging the node capacitor with a negative voltage are combined in a predetermined binary sequence A drive circuit output to a signal line;
A sensing circuit electrically connected to the plurality of sensing signal lines, the sensing circuit measuring a sensing voltage transmitted from one node capacitor to one integration capacitor electrically connected to a corresponding sensing signal line; And
And a sensing recognition unit for measuring capacitance corresponding to each node capacitor by performing an addition or subtraction operation of the sensing voltage measured by the sensing circuit in a predetermined binary sequence for each driving time point. 10. The method of claim 9,
The driving circuit includes a plurality of unit drivers for applying respective driving waveforms to corresponding operation signal lines,
Each unit driving unit
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 10,
And the first voltage and the second voltage have the same magnitude. The method of claim 10,
The sensing circuit
A first sensing switch electrically connected between the common other ends of the plurality of node capacitors and a fourth voltage;
An integrating capacitor electrically connected to the other ends of the plurality of node capacitors, the integrating capacitor being charged by transferring a sense voltage proportional to an operation value of capacitances of the plurality of node capacitors; And
And a second sensing switch electrically connected between the common ends of the plurality of node capacitors and the integrating capacitor, the second sensing switch being configured to switch a unit charge voltage to the integrating capacitor. The method of claim 12,
And wherein the second voltage and the fourth voltage are ground voltages. 14. The method according to any one of claims 9 to 13,
And a first binary sequence simultaneously applied to the plurality of operation signal lines at a first driving time and a second binary sequence simultaneously applied to the plurality of operation signal lines at a second driving time are orthogonal to each other. 14. The method according to any one of claims 9 to 13,
And a third binary sequence applied to the first operation signal line by a plurality of driving time points and a fourth binary sequence applied to the second operation signal line by a plurality of driving time points are orthogonal to each other. 16. The method of claim 15,
The detection recognition unit
By adding or subtracting the sensed voltage measured by the sensing circuit for each driving time in the same sequence as the binary sequence applied for each driving time, the capacitance of the corresponding node capacitor is measured. Drive system. 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 formed by corresponding operation signal lines and corresponding detection signal lines, respectively. ,
A corresponding operation waveform in which a driving waveform of a first mode for charging the node capacitor with a positive voltage and a driving waveform of a second mode for charging the node capacitor with a negative voltage are combined in a predetermined binary sequence Outputting to a signal line;
Measuring a sensing voltage transmitted to each integrated capacitor from each of the plurality of node capacitors electrically connected to the corresponding sensing signal lines for each driving time point; And
And measuring capacitance corresponding to each node capacitor by performing an addition or subtraction operation of the sensed voltage measured for each driving time in a predetermined binary sequence. 18. The method of claim 17,
The positive voltage charged in the node capacitor and the negative voltage is the same size, the driving method of the touch panel. 19. The method of claim 18,
And a first binary sequence simultaneously applied to the plurality of operation signal lines at a first driving time and a second binary sequence simultaneously applied to the plurality of operation signal lines at a second driving time are orthogonal to each other. 19. The method of claim 18,
And a third binary sequence applied to the first operation signal line by a plurality of driving time points and a fourth binary sequence applied to the second operation signal line by a plurality of driving time points are orthogonal to each other. 21. The method of claim 20,
And wherein the binary sequence of the add or subtract operation is the same as the binary sequence applied for each driving time point to the corresponding operation signal line.

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