KR101926546B1 - Position sensing method of touch panel and integrated circuit - Google Patents

Abstract

A method of detecting a position of a touch panel according to an exemplary embodiment of the present invention is a method of detecting a position of a Y electrode pair pair according to a position where a plurality of X electrode lines and Y electrode lines cross each other and are adjacent to each other Into at least one comparator connected between adjacent Y electrode line pairs; Inputting a constant sum signal to the at least one comparator; And comparing the position signal and the addition signal by a comparator to detect a position.

Description

TECHNICAL FIELD [0001] The present invention relates to a position detecting method and an integrated circuit for a touch panel,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of detecting the position of a capacitive touch panel and an integrated circuit.

2. Description of the Related Art Generally, personal computers, portable communication devices, and other personal-purpose information processing devices constitute interfaces with users by using various input devices such as a keyboard, a mouse, and a digitizer.

On the other hand, as the use of personal computers is expanded, input devices such as a keyboard and a mouse are difficult to enhance the completeness of the product, so that it is simpler and can reduce malfunctions, .

In response to this demand, a touch panel has been proposed in which a user directly touches the screen with a hand or a pen to input information. The touch panel is simple, has few malfunctions, is easy to carry, can input characters without any other input device, and has a merit that a user can easily recognize a usage method.

Such a touch panel senses the coordinates of a contact point, and a metal electrode is formed on the upper plate or the lower plate, and a resistive type (Resistive type A capacitance type in which an equal potential is formed on a conductive film and a position where a voltage change of the upper and lower plates due to the contact is sensed, a LC value derived from the contact of the electronic pen with the conductive film is read, And an electromagnetic induction type (electro magnetic type) for sensing.

It is an object of the present invention to provide a method of detecting a position of a touch panel which is resistant to noise and an integrated circuit

A method of detecting a position of a touch panel according to an exemplary embodiment of the present invention is a method of detecting a position of a Y electrode pair pair according to a position where a plurality of X electrode lines and Y electrode lines cross each other and are adjacent to each other Into at least one comparator connected between adjacent Y electrode line pairs; Inputting a constant sum signal to the at least one comparator; And comparing the position signal and the addition signal by a comparator to detect a position.

According to an embodiment of the present invention, an integrated circuit includes a plurality of comparators having a plurality of input terminals for receiving different position signals and addition signals according to a touched position, and an output terminal for outputting a comparison signal of the position signal and the addition signal; And an operation unit for reading a comparison signal of the plurality of comparators and generating a position signal.

According to embodiments of the present invention, there is provided a method and an integrated circuit for detecting a position of a touch panel that is strong against noise and improved in efficiency by detecting contact positions according to output values of a plurality of comparators connected between adjacent Y electrode lines .

1 is a circuit diagram showing a configuration of a touch panel according to a first embodiment of the present invention.
2 is a view for explaining a change in capacitance due to the contact of an object.
Figs. 3 to 11 are views for explaining embodiments of a method of detecting a touch position on a touch screen. Fig.
12 is a circuit diagram showing a configuration of a touch panel according to a second embodiment of the present invention.
13 is a circuit diagram showing an embodiment of a configuration of a comparator provided in a touch panel.
14 is a diagram for explaining another embodiment of a method of detecting a touch position on a touch screen.
15 is a diagram illustrating a touch panel signal sensing circuit including a CMP block according to an embodiment of the present invention.
16 is a diagram illustrating an example of a CMP block according to an embodiment of the present invention.
17 and 18 are diagrams showing CMP block control signal timing in a normal operation mode according to an embodiment of the present invention

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

1 is a circuit diagram showing a configuration of a touch panel according to a first embodiment of the present invention.

Referring to FIG. 1, the touch panel includes a plurality of X electrode lines TX ₁ to TX _n and a plurality of Y electrode lines RX ₁ to RX _m (Not shown).

The contact position on the touch screen 100 detects whether the capacitance generated between the X electrode lines TX ₁ to TX _n and the Y electrode lines RX ₁ to RX _m is fluctuated, As shown in FIG.

2, when a finger of a user touches a specific position on the touch screen 100, an effective value of a coupling capacitor at an intersection of an X electrode line and a Y electrode line corresponding to the contact position the effective value may be reduced by a certain value (e.g., C _M ).

On the other hand, as shown in Fig. 1, the touch panel may be configured to include another electronic component for detecting the contact position on the touch screen 100, and the other electronic components may be an " on- The other electronic components may be implemented as a separate IC chip from the touch screen 100 or in the same film as the electrode lines on the touch screen 100 in the case of an " in-cell " touch panel.

Further, according to the embodiment of the present invention, a plurality of comparators are connected between two Y electrode lines adjacent to each other, and a touch position on the touch screen 100 is detected according to an output code configured using output values of the comparators .

Hereinafter, it is assumed that the two adjacent Y electrode lines are two Y electrode lines arranged continuously in one direction, but the adjacent two Y electrode lines are arranged close to each other and one or more Y electrode lines are arranged therebetween And the like.

Hereinafter, embodiments of a method for detecting a touch position on the touch screen 100 will be described in detail with reference to FIGS. 3 to 11. FIG.

Referring to FIG. 3, when the user touches the finger T in the region T where the TX ₁ electrode line and the RX ₂ electrode line intersect, the coupling capacitance between the TX ₁ electrode line and the RX ₂ electrode line is the same as that of the conventional C _E Lt _; RTI ID = 0.0 > C < / RTI > That is, the coupling capacitance between the X electrode line and the Y electrode line in the region corresponding to the contact position may have a value of (C _E -C _M ).

4 to 7, a ground voltage GND is applied to the X electrode lines TX ₁ to TX _n and a voltage V _DD / 2 is applied to the Y electrode lines RX ₁ to RX _m .

For this purpose, a ground voltage (GND) is applied to another TD electrode line (TD) formed in a direction crossing the Y electrode lines (RX ₁ to RX _m ) and? 3, and V _DD A voltage can be applied.

The touch panel according to an exemplary embodiment of the present invention includes a TX decoder 110 for applying a voltage to the electrode lines as described above and includes a voltage generator 120 for applying a voltage of V _DD / can do.

Then t0 time, φ1 and the ground voltage (GND) to φ4 is applied, is applied to the V _DD voltage φ3, the X electrode lines (TX ₁ ~ TX _n) and the comparator (i.e., the 1 Y electrode lines The two comparators C1-1 and C1-2 connected between the first Y electrode line RX1 and the second Y electrode line RX2 have a sampling hold voltage level of V _DD / 2.

Then, at time t1, when the VDD voltage is applied to the TX ₁ electrode line, the voltages of the RX ₁ electrode line, the RX ₂ electrode line, and the RX ₃ electrode line may be as shown in the following equation (1).

Where C _E represents the capacitance of each of the coupling capacitors at the intersections of the X and Y electrode lines, n is the number of X electrode lines arranged on the touch screen 100, and C _{And M} represents a negative capacitance formed according to the finger contact of the user.

Also, C _s represents the capacitance of the sampling voltage holding capacitors, and C _D represents the capacitance of the dummy capacitors.

The dummy capacitor C _D is formed in the same manner as the dielectric material in which the C _E or C _M is formed so that the differential gating off-balance resulting from the dielectric parameter fluctuation Can be reduced.

A TD electrode line TD and a dummy TX line may be added to form the dummy capacitor C _D and a ground voltage GND may be applied to the dummy TX line. have. A dummy capacitor (CD) is formed between the TD electrode line (TD) and the Y electrode line (RX). On the other hand, the capacitance formed between the TD electrode line TD and the dummy TX line does not affect the signal sensing operation, but the dummy TX line is electrically connected to the TD electrode line TD And functions as an electric field shielding layer and functions as a C _M formed between the finger of the user and the Y electrode line RX. When a user's finger touches the glass plate, an electric field is formed between the finger and the Y electrode line RX, and the electric field between the X electrode line TX and the Y electrode line RX is distorted , Whereby the effective capacitance value coupled to the Y electrode line RX can be reduced by CM. In this case, the finger acts like a ground electrode, because the human body is like a huge capacitor.

When a voltage is applied from time t2 to φ5 changed to VDD, S1b becomes a S2c and cut off from the tearing (disconnected), RX ₂ electrode lines S1c from the electrode RX1 line S2b becomes the RX ₃ cut off from the electrode lines.

Thus, the capacitor C _s is connected to the S1b, S1c, S2b and S2c may maintain a _{V RX1 (t1), V RX2} (t1) and V _RX3 (t1).

On the other hand, in the t3 time, when the voltage to be applied to the TD electrode lines (TD) changes from the ground voltage (GND) to V _DD / 2, the voltage of the RX ₁ electrode line, RX ₂ electrode lines and RX ₃ electrode line is then of (2) " (2) " In the above, the added voltage applied to the TD is set to V _DD / 2, but is not limited thereto.

Thereafter, when the ground voltage (GND) to φ6 from the t4 time of application, the S1a is disconnected from RX ₁ electrode line, that S1d and S2a becomes disconnected from the RX ₂ electrode lines, it becomes S2d is disconnected from the RX ₃ electrode lines.

Thus, the capacitor C _s is connected to the S1a, S1d, S2a and S2d may maintain _RX1 V (t3), V _RX2 (t3) and _RX3 V (t3).

Therefore, the difference of the input levels for each of the comparators C1-1, C1-2, C2-1, and C2-2 can be calculated as Equation (3).

Assuming that C _D and C _M are equal in Equation (3), the output values of the comparators (C1-1, C1-2, C2-1, C2-2) are 1, 1, 0, 0 .

At this time, the output code for detecting the touch position on the touch screen 100 may be configured using the output values of the comparators C1-1, C1-2, C2-1, and C2-2. For example, As shown in FIG. 1, the logical AND of the output values of the first comparator C1-1 and the second comparator C1-2 is set to a first value, and the output of the first comparator C1-1 Value to the second value.

Specifically, the output codes [O _{1 -1} , O _1-0 ] for the RX ₁ and RX ₂ electrode lines are [1, 1], and the output codes for the RX ₂ and RX ₃ electrode lines The output code [O _{2 -1} , O _{2 -0} ] can be [0,0].

That is, it can be seen that the contact position exists on the RX ₂ electrode line by the output code [1, 1] for the RX ₁ electrode line and the RX ₂ electrode line.

On the other hand, it can be seen that the contact position exists on the RX ₂ electrode line because the output code for the RX ₂ electrode line and the RX ₃ electrode line is [0, 0].

According to the above method of detecting the contact position, when the output code for any two Y electrode lines is [1, 1], there is a contact position on the Y electrode line located on the right of the two Y electrode lines .

Conversely, when the output code for any two Y electrode lines is [0, 0], it can be determined that a contact position exists on the Y electrode line located to the left of the two Y electrode lines.

In addition, as shown in Figs. 8 and 9, if both of the finger electrodes are not in contact with two Y electrode lines adjacent to each other, or if two fingers are present on both Y electrode lines adjacent to each other as shown in Figs. 10 and 11 The difference of the input levels for the comparators C3-1, C3-2, C5-1, and C5-2 may be expressed by Equation (4).

According to Equation (4), the output codes [O _{3 -1} , O _{3 -0} ] for the RX ₃ electrode line and the RX ₄ electrode line both of which are not in contact with the finger are [0, 1] The output codes [O _{5 -1} , O _{5 -0} ] for the RX ₅ electrode line and the RX ₆ electrode line are both [0, 1], so that the case where both of the fingers are not in contact with each other May not be distinguished from each other by the output code.

In this case, whether or not the two adjacent Y electrode lines having the [0, 1] output code are in contact with each other can be determined according to the output codes for the Y electrode lines adjacent to each other.

For example, if the output code [O _1-1 , O _{1 -0} ] for the Y electrode lines adjacent to the leftmost _one is [0, 0], there is a contact position on the RX ₁ electrode line, There is no contact position on the RX ₂ electrode line.

If the output code [O _{2 -1} , O _{2 -0} ] for the next adjacent Y electrode lines is [0, 1], the voltage difference between the RX ₂ electrode line and the RX ₃ electrode line is 0, _{a three-electrode} in-line to the contact position does not _{exist, [O 3 -1, O 3} -0] may be determined that the contact position in the [0, 1] when the RX line electrode ₄ is not present.

On the other hand, the output codes for the adjacent Y electrode lines arranged on the left side _[-1 O _1, O _{1 -0]} is [1,1] is, the contact position present on the RX line electrode _2, and RX ₁ There is no contact position on the electrode line.

If the output code [O _{2 -1} , O _{2 -0} ] for the next adjacent Y electrode lines is [0, 1], the voltage difference between the RX ₂ electrode line and the RX ₃ electrode line is 0, _The contact position is also present on the _3- electrode line, and when [O _{3 -1} , O _{3 -0} ] is [0, 1], it can be judged that the contact position exists also on the RX ₄ electrode line.

If the output codes [O _1-1 , O _{1 -0} ] for the adjacent Y electrode lines disposed at the leftmost side are [0, 1], they are all located on the RX ₁ electrode line and the RX ₂ electrode line Or there may be a contact position on both the RX ₁ electrode line and the RX ₂ electrode line.

In this case, until the output code of [0,0] or [1,1] appears, it can be assumed that the contact position does not exist first.

For example, when [O _{5 -1} , O _{5 -0} ] is [0, 0], it is judged that all the contacts are from the RX ₁ electrode line to the RX ₅ electrode line and there is no contact position on the RX ₆ electrode line .

On the other hand, if [O _{5 -1} , O _{5 -0} ] is [1, 1], it is judged that no contact is made from the RX ₁ electrode line to the RX ₅ electrode line and a contact position exists on the RX ₆ electrode line .

On the other hand, when all the output codes are [0, 1], it can be judged that they are in contact with or not in contact with all the Y electrode lines. In this case, All the points are intentionally contacted, so that a specific operation according to the touch input can be prevented from being performed.

12 is a circuit diagram showing the configuration of the touch panel according to the second embodiment of the present invention. The description of the same structure as that described with reference to Figs. 1 to 11 of the structure and operation of the touch panel shown in Fig. 12 Hereinafter, it will be omitted.

12, a? 2 line is added in place of the TD electrode line TD shown in FIG. 1, and a voltage applied to the TD electrode line TD is applied to the? 2 line to make reference to FIGS. 1 to 11 The operation of the touch panel as described above can be performed.

In this case, a change in capacitance due to the contact of the user's finger or the like with the region where the TD electrode line TD is disposed can be prevented.

Meanwhile, the touch sensitivity of the touch can be increased or decreased by changing the high level voltage (TD high level) applied to the TD electrode line (or the? 2 line).

For example, when the high level voltage applied to the TD electrode line is V _DD / 2 as described above, the input voltage differences of the first comparator C1-1 and the second comparator C1-2 are (5) " (5) "

Assuming that the capacitance variation C _M due to the finger contact of the user has a value between 0 and C _m , the following equation 6 can be derived from the equation (5).

In this case, the output value of the first comparator (C1-1) regardless of the value of the capacitance C _M is 1, but the output value of the second comparator (C2-1) is the capacitance value of the C _{M m} is less than 0.5C Can have a value of zero.

Meanwhile, when the high level voltage applied to the TD electrode line is 0.2V _DD , the input voltage differences of the first comparator C1-1 and the second comparator C1-2 can be expressed by the following Equation (7) have.

Assuming that C _{M, which} is a change amount of capacitance due to the finger contact of the user, has a value between 0 and C _m , the following relation can be derived from the above Equation (7).

In this case, the output value of the first comparator (C1-1) regardless of the value of the capacitance C _M is 1, but the output value of the second comparator (C2-1) is the capacitance value of the C _{M m} is less than 0.2C Can have a value of zero.

That is, as the high level voltage applied to the TD electrode line decreases from 0.5V _DD to 0.2V _DD , the finger contact and non-contact capacitance threshold can be enlarged by 60%.

The touch sensitivity can be adjusted in the case of the second comparator C2-1 and the fourth comparator C2-2.

That is, when the high level voltage applied to the TD electrode line is V _DD / 2, the input voltage differences of the third comparator C2-1 and the fourth comparator C2-2 are expressed by Equation (9) .

When the high level voltage applied to the TD electrode line is 0.2V _DD , the input voltage differences of the third comparator C2-1 and the fourth comparator C2-2 can be expressed by Equation 10 below have.

In this case, although the output value of the third comparator (C2-1) regardless of the value of the capacitance C _M is 1, the output value of the fourth comparator (C2-2) is the capacitance value of the C _{M m} is less than 0.2C Can have a value of zero.

As a result, as the high level voltage applied to the TD electrode line decreases from 0.5V _DD to 0.2V _DD , the finger contact and non-contact capacitance thresholds can be enlarged by 60%.

If the high level voltage applied to the TD electrode line is 0.5 V _DD, then the differences of the input voltages of the respective comparators are the following: Can be calculated as shown in Equation (11).

If the high level voltage applied to the TD electrode line is 0.2 V _DD, then the differences of the input voltages of the respective comparators are the following: (12) " (12) "

In the above Equations (11) and (12), the output values of the comparators are the same regardless of the high level voltage applied to the TD electrode line.

As a result, the sensitivity of the finger contact can be increased by decreasing the high level voltage applied to the TD electrode line.

FIG. 13 is a circuit diagram showing an embodiment of a configuration of a comparator provided in a touch panel, and FIG. 14 is a view for explaining another embodiment of a method of detecting a touch position on a touch screen. The description of the detection method shown in Fig. 14 that is the same as that described with reference to Figs. 1 to 12 will be omitted below.

13, the comparator may be operated at a time t5 shown in FIG. 14, for example, after the voltage difference at the input terminals of the comparator occurs, and the operation of the comparator is deactivated until the time point (i.e., t5) or de-activated.

The control signals? 5 to? 9 for the comparator can follow the timing diagram as shown in FIG. 14, and? 7 is set to V _DD up t5, and? 8 and? 9 are set to the ground voltage GND Can be set.

Then, when V _DD is applied to? 8 at time t5, the operation of the comparator is started and the same series of operation sequences as those used in DRAMs are performed.

In the above, for the two comparators (e.g., between Fig. 1 through 14 with reference to the one-way two of Y electrode lines continuously arranged in a (e. G., RX _first electrode line and the RX _second electrode lines), C1 -1 and C1-2) are connected to each other. However, the present invention is not limited thereto.

For example, two comparators may be connected between two Y electrode lines (e.g., RX ₁ electrode line and RX ₃ electrode line) in which at least one Y electrode line is disposed.

1, when Y electrode lines arranged in a line are alternately connected to IC chips provided on both sides of the touch screen 100 (for example, odd-numbered Y electrode lines And the even-numbered Y electrode lines are connected to the second IC chip provided on the right side), two Y electrode lines arranged adjacent to each other with one Y electrode line therebetween, Two comparators may be connected between the two comparators.

According to another embodiment of the present invention, two comparators are connected between two adjacent Y electrode lines. However, according to another embodiment of the present invention, three Or more comparators may be connected.

Also, as the number of the comparators connected between two adjacent Y electrode lines increases, the touch sensitivity for detecting the touch position of the touch panel according to the embodiment of the present invention can be improved.

The driving algorithm related to the above-described method of operating the touch panel may be applied to an integrated circuit (IC), and the integrated circuit may be implemented by being applied to a driving chip of a touch panel.

The IC includes a plurality of comparators having a plurality of input terminals for receiving different position signals and addition signals according to a touched position, and an output terminal for outputting a comparison signal of the position signal and the addition signal; And an operation unit 150 for reading a comparison signal of the plurality of comparators and generating a position signal.

Wherein the plurality of comparators include a first comparator and a second comparator connected in parallel, a first input terminal is connected to one end of the first comparator and the second comparator, and a second input terminal is connected to the other end of the first comparator and the second comparator, 2 input terminal is connected.

And one of the position signal and the add signal is input to a first input terminal of the first comparator and a second input terminal of the second comparator and the other of the position signal and the add signal is input to a second input terminal of the first comparator, Input terminal and the first input terminal of the second comparator.

When the plurality of comparators connected in parallel are grouped, the calculating unit 100 may generate a position signal by receiving a comparison signal of a comparator of another adjacent group.

Also, a capacitor element may be mounted on the integrated circuit chip Chip to form the dummy capacitor C _D.

The capacitor element may be formed of, for example, a MOS capacitor.

In addition, the integrated circuit can be mounted on a touch panel alone, or in a single chip (ONE-CHIP) integrated with at least one of a chip of an individual portable terminal or an LCD driving chip.

15 is a diagram illustrating a touch panel signal sensing circuit including a CMP block according to another embodiment of the present invention. 16 is a diagram illustrating a CMP block according to another embodiment of the present invention. 17 and 18 are views showing CMP block control signal timing in a normal operation mode according to another embodiment of the present invention.

15 and 16, CTCMP, RST, and VRAMP may be input to the CMP block. The output terminal of the CMP block may be connected to the Y electrode line.

The CMP block includes a logic circuit, and a plurality of XOR gates can be connected in parallel. The output of the CTCMP 2b and the output of the 2b memory may be input to the XOR gate, and the plurality of XOR gate outputs may be respectively connected to the input of the NOR gate.

The output of the NOR gate is input to S of the RS latch circuit, and the grounded RST after t0 can be input to the RS of the RS latch circuit. N2 may be determined according to the input combination of S and R of the RS latch circuit.

Referring to FIG. 17, a ground voltage (GND) is applied to the X electrode lines (TX1 to TXn) and a voltage of VDD / 2 is applied to the Y electrode lines (RX1 to RXm) before t0.

For this purpose, a ground voltage (GND) may be applied to another TD electrode line (TD) formed in a direction crossing the Y electrode lines (RX1 to RXm) and? 9.

The touch panel according to an embodiment of the present invention includes a TX decoder 110 for applying a voltage to the electrode lines, and a voltage generator 120 for applying a voltage of VDD / 2 .

The ground voltage GND is applied to the first and second Y electrode lines RX1 and RX2 at the time point t0 so that the X electrode lines TX1 to TXn and the comparators (i.e., the first Y electrode line RX1 and the second Y electrode line RX2 ) Have a sampling hold voltage level of VDD / 2. In this case, the comparators C1-1 and C1-2 have a sampling hold voltage level of VDD / 2.

Then, at time t1, when the VDD voltage is applied to the TX1 electrode line, the voltages of the RX1 electrode line and the RX2 electrode line are raised by CE1 and CE2. The CE represents the capacitance of each of the coupling capacitors at the intersections of the X electrode line and the Y electrode line.

Ideally, the coupling capacitors at the intersections of the X electrode line and the Y electrode line are the same but are not so, so that the voltage difference (DELTA VRX1-2) between the RX1 electrode line and the RX2 electrode line is generated.

The voltage difference can be caused by the coupling capacitance due to CE1 and CE2 and / or the parasitic capacitance of the RX electrode line due to the difference between CR1P and CR2P, and all kinds of non-symmetries structures.

In order to reduce the reliability of the touch panel by the voltage difference DELTA VRX1-2, a voltage difference DELTA VRX1-2 compensation (CMP) block is provided for each of the RX1 electrode line and the RX2 electrode line As shown in FIG.

Δ VRX1-2 The CMP block can add 0, ΔVCMP, 2ΔCMP, and 3ΔCMP values to VRX1 and VRX2 in the 2b (bit) system. In the 3b compensation system, it can be compensated in 8 steps from 0 to 7 △ VCMP.

The 2b CMP code is generated before the normal touch sensing operation and can be stored in the memory as shown in FIG.

The? VRX1-2 compensation voltage added to VRX1 and VRX2 in the normal touch sensing operation mode is as follows.

When? VRX1-2? 2.5 VCMP, i.e., VRX1? VRX2 + 2.5? VCMP, the voltage of 3? VCMP is added to VRX2. Here,? VCMP is a set value and can have different values depending on the circuit. Similar to the above formula,

1.5? VCMP? DELTA VRX1-2 < 2.5 DELTA VCMP, the value of 2 DELTA VCMP is added to VRX2.

0.5? VCMP? DELTA VRX1-2 < 1.5 DELTA VCMP, the value of DELTA VCMP is added to VRX2.

-0.5? VCMP?? VRX1-2 <0.5? VCMP, no value is added.

-1.5 DELTA VCMP &lt; DELTA VRX1-2 &lt; -0.5 DELTA VCMP, the value of 2 DELTA VCMP is added to VRX1.

-2.5 DELTA VCMP &amp;le; DELTA VRX1-2 &lt; -1.5 DELTA VCMP, the value of 2 DELTA VCMP is added to VRX1.

If? VRX1-2 <-2.5? VCMP, the value of 3? VCMP is added to VRX1.

The voltage difference compensation block may be formed on each Y electrode line.

Hereinafter, an output generation process of the voltage difference compensation block will be described. For the sake of explanation, when the CMP code is 00, it is assumed that the DELTA VRX1-2 CMP block is formed in the RX1 electrode line.

The following relation can be established between the compensation voltage [Delta] VCMP and the output voltage [Delta] VCMP_B of the CMP block.

The CCMP represents the capacitance inside the DELTA VRX1-2 CMP block as shown in Fig. And CPRX represents a parasitic capacitance formed in the Y electrode line.

In the standby state, that is, in the state before t0, since RST is a high (H) signal and VRAMP is 0V, the voltage of the node N2 is 0V.

As shown in Fig. 17, VRAMP is synchronized to? VCMP_B at time t1-1, to 2? VCMP_B at time t1-2, and to 3? VCMP_B at time t1-3.

Next, the time t0 will be described. 2b If the CMP code is 00, N1 is H. S, R and Q have a value of H, and Q-bar has a value of L. Q and Q-bar are not inverted to the state of H and L until t8 where touch is sensed. That is, when RST becomes H at t8, Q becomes L and Q-bar becomes H. Since the gate of the transfer is off, the output voltage of the N2 node is 0 V, and therefore the voltage does not fluctuate.

Then, at t1-1, VRAMP rises to? VCMP_B, N2 rises to? VCMP_B, and VRX2 rises by? VCMP. 2b If the CMP code is 01, the node N1 will have an H value, S, R and Q will be H, and Q-bar will have a value of L. The transfer gate switch is turned off, and? VCMP_B is held at the node N2, so that RX2 has values of VRX2 and? VCMP.

If the CMP 2b code is not 01, N1 will maintain a value of L, S, R and Q will be L, and Q-bar will have a value of H.

In a similar way, depending on the CMP code, 2? VCMP or 3? VCMP may be added to VRX2.

Hereinafter, a process of generating a CMP code will be described with reference to FIG.

In the normal touch sensing operation mode, the value of VRAMP sequentially increases from 0 V to 3 VCMP-B. In the CMP code generation mode, the value of VRAMP is increased to one of 0.5ΔC VCMP-B, 1.5ΔCMP-B, and 2.5ΔCMP-B at one time in one sequence period, ie, at 0V.

As shown in Fig. 18, the value of VRAMP increases from 0 V to 0.5 DELTA VCMP-B in the first sequence period, the value of VRAMP increases from 0 V to 1.5 DELTA VCMP-B in the second sequence period, In the sequence period, the value of VRAMP increases from 0 V to 2.5 DELTA VCMP-B.

In this embodiment, the value of VRAMP varies from 0 V to 0.5 DELTA VCMP-B in the first sequence period, from 1.5 V to 1.5 DELTA VCMP-B in the second sequence period, and from 2.5 V to 0.9 DELTA VCMP-B in the third sequence period As an example.

In the first sequence period, the value of VRAMP increases from 0 V to 0.5 DELTA VCMP-B. The comparator C1-1 compares the values of VRX1 and VRX2 + 0.5 DELTA VCMP. The comparator C1-2 compares the values of VRX1 + 0.5 DELTA VCMP and VRX2.

In the second sequence period, the comparator C1-1 compares the values of VRX1 and VRX2 + 1.5 DELTA VCMP. The comparator C1-2 compares the values of VRX1 + 1.5ΔVCMP and VRX2.

In the third sequence cycle, the comparator C1-1 compares the values of VRX1 and VRX2 + 2.5 DELTA VCMP. The comparator C1-2 compares the values of VRX1 + 2.5ΔVCMP and VRX2.

When VRX1 &gt; VRX2 + 2.5 DELTA VCMP, the comparator (C1-1) and the comparator (C1-2) output the code of 11 in every sequence period.

When VRX1 = VRX2 + 2.5 DELTA VCMP, the comparator (C1-1) and the comparator (C1-2) output a code of 11 in the first and second sequence periods, but in the third sequence period, 00, 10, 01 or 11 Can be output. That is, the output code value in the third sequence period is unpredictable. Since the code of 11 is output in the previous second sequence period, when 10 or 00 is output in the third sequence period, it can be seen that VRX1≈VRX2 + 2.5ΔCVPM. If a code of 11 or 01 is output in the third sequence period, the situation that VRX1≈VRX2 + 2.5ΔVCMP is erroneously classified as ΔVRX1-2> 2.5ΔVCMP or 1.5ΔVCMP <ΔVRX1-2 <2.5ΔCMP . However, this is a problem in the boundary region, so it does not greatly affect the sensing sensitivity.

1.5? VCMP <? VRX1-2 <2.5? VCMP, the comparator (C1-1) and the comparator (C1-2) output a code of 11 in the first and second sequence periods and a code of 01 Output the code.

When? VRX1-2? 1.5? VCMP, the comparator (C1-1) and the comparator (C1-2) output 11 code in the first sequence period and 01 code in the third sequence period. In the second sequence cycle, one of 11, 10, 01, or 00 can be output.

0.5 VCAM <DELTA VRX1-2 <1.5 DELTA VCMP, the comparators C1-1 and C1-2 output a code of 11 in the first sequence period and a code of 11 in the second and third sequence periods Output the code.

The comparator C1-1 and the comparator C1-2 output a code of 01 in the second and third sequence periods, and 11, 10, 01, or 11 in the first sequence period when? VRX1-2? 00 &lt; / RTI &gt;

-0.5? VCMP <? VRX1-2 <0.5? VCMP, the comparator (C1-1) and the comparator (C1-2) output a code of 01 in every sequence cycle.

In the case of? VRX1-2? -0.5? VCMP, the comparator C1-1 and the comparator C1-2 output a code of 01 in the second and third sequence periods and 11, 10, 01 Or 00 can be output.

-1.5 DELTA VCMP &lt; DELTA VRX1-2 &lt; -0.5 DELTA VCMP, the comparator C1-1 and the comparator C1-2 output a code of 00 in the first sequence period, and the second and third sequence cycles The code of 01 is output.

In the case of? VRX1-2? -1.5? VCMP, the comparator C1-1 and the comparator C1-2 output a code of 00 in the first sequence period, a code of 01 in the third sequence period, In the second sequence cycle, one of 11, 10, 01, or 00 can be output.

-2.5 DELTA VCMP <DELTA VRX1-2 <-1.5 DELTA VCMP, the comparator C1-1 and the comparator C1-2 output a code of 00 in the first and second sequence periods, and the third sequence cycle The code of 01 is output.

In the case of? VRX1-2? -2.5? VCMP, the comparator C1-1 and the comparator C1-2 output a code of 00 in the first and second sequence periods, and 11, 10, 01 &quot; or &quot; 00 &quot;.

When? VRX1-2 <-2.5? VCMP, the comparator (C1-1) and the comparator (C1-2) output a code of 00 in every sequence period.

Based on the above code value,? VRX1-2 can be determined as follows.

In the case of? VRX1-2? 2.5 VCMP, the code output values of the first, second, and third sequence periods are all 11. In this case, in order to reduce the voltage difference, no voltage is added to VRX1 in the normal operation mode, and a voltage of 3 DELTA VCMP is added to VRX2. In FIG. 15, the 2b memory of the left block connected to RX1 outputs a code of 00, and the 2b memory of the right block connected to RX2 outputs 11 code.

1.5? VCMP? VRX1-2 <2.5? VCMP, the code output value of the first and second sequence periods is 11, and the output value of the third sequence period is not 11. In this case, no voltage is added to VRX1, and a voltage of 2ΔCVMP is added to VRX2. The 2b memory of the left block connected to RX1 outputs the code of 00, and the 2b memory of the right block connected to RX2 outputs the code of 10.

0.5 VCMP &amp;le; VRX1-2 &lt; 1.5 DELTA VCMP, the code output value of the first sequence period is 11 and the output value of the second sequence period is not 11. And the output value of the third sequence period is 01. In this case, no voltage is added to VRX1, and a voltage of DELTA VCMP is added to VRX2. The 2b memory of the left block connected to RX1 outputs the code of 00, and the 2b memory of the right block connected to RX2 outputs 01 code.

-0.5 DELTA VCMP &lt; DELTA VRX1-2 &lt; 0.5 DELTA VCMP, the code output value of the first sequence period is 01 or 10, and the output value of the second sequence period is 01. And the output value of the third sequence period is 01. In this case, no voltage is added to VRX1 and VRX2. 2b memory of the left block connected to RX1 outputs 00 code, and 2b memory of right block connected to RX2 outputs 00 code.

-1.5 DELTA VCMP <DELTA VRX1-2? -0.5 DELTA VCMP, the code output value of the first sequence cycle is 00, the output value of the second sequence cycle is not 00, and the output value of the third sequence cycle is 01. In this case, the voltage of? VCMP is added to VRX1, and the voltage is not added to VRX2. The 2b memory of the left block connected to RX1 outputs 01 code, and the 2b memory of the right block connected to RX2 outputs 00 code.

-2.5? VCMP <? VRX1-2? -1.5? VCMP, the code output value of the first sequence period is 00, the output value of the second sequence period is 00, and the output value of the third sequence period is not 00. In this case, the voltage of 2 △ VCMP is added to VRX1, and no voltage is added to VRX2. 2b memory of the left block connected to RX1 outputs 10 code, and 2b memory of right block connected to RX2 outputs 00 code.

DELTA VRX1-2? -2.5? VCMP, the code output value of the first sequence period is 00, the output value of the second sequence period is 00, and the output value of the third sequence period is 00. In this case, a voltage of 3ΔCMP is added to VRX1, and no voltage is added to VRX2. 2b memory of the left block connected to RX1 outputs 11 code, and 2b memory of right block connected to RX2 outputs 00 code.

The above is a case of two RX line systems, and the case of two or more electrode lines will be described below.

0.5? VCMP <? VRX1-2? 1.5? VCMP, the case where? VCMP is added to VRX2 has been described above. In this case, when -1.5 DELTA VCMP &amp;le; VRX2-3 &lt; -0.5 DELTA VCMP, DELTA VCMP is added to VRX2 and no voltage is added to VRX3. That is, no voltage is added to VRX1, the voltage of DELTA VCMP is added to VRX2, and no voltage is added to VRX3.

For example, when 0.5? VCMP <? VRX1-2? 1.5? VCMP and 0.5? VCMP <? VRX2-3? 1.5? VCMP, no voltage is added to VRX1 and a voltage of? VCMP is added to VRX2 And the voltage of DELTA VCMP is added to VRX3. As described above, the present invention can also be applied to two or more electrode lines.

Meanwhile, the method of detecting the touch position of the touch panel according to the present invention may be stored in a computer-readable recording medium. The computer readable recording medium may be a ROM, A RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like, as well as a carrier wave (for example, transmission via the Internet).

The computer readable recording medium may be distributed over a networked computer system so that computer readable code can be stored and executed in a distributed manner. And, functional programs, codes and code segments for implementing the above method can be easily inferred by programmers of the technical field to which the present invention belongs.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

Claims (15)

A plurality of X electrode lines and a plurality of Y electrode lines intersecting with each other are arranged such that a position signal of a Y electrode pair pair different from each other depending on a position adjacent to and in contact with each other is connected to at least one Inputting to a comparator;
Inputting a constant sum signal to the at least one comparator; And
Comparing the position signal and the addition signal by a comparator to detect a position,
Wherein the at least one comparator includes a first comparator and a second comparator connected in parallel, and wherein the at least one comparator has a first input terminal of the first comparator and a second input terminal of the second comparator, Detection method. delete The method according to claim 1,
The position signal is input to a second input terminal of the first comparator and a first input terminal of the second comparator,
A comparator for comparing a position signal inputted to the first comparator and a second comparator with a sum signal to input a comparison value to a logic circuit,
The position of the touch panel is detected by the output code value of the Y electrode line pair and the output code value of the Y electrode line pair adjacent to the right and left sides of the Y electrode line pair. delete delete A plurality of comparators having a plurality of input terminals for receiving different position signals and addition signals according to positions to be touched and output terminals for outputting comparison signals of the position signals and the addition signals; And
And an operation unit for reading a comparison signal of the plurality of comparators to generate a position signal,
The plurality of comparators including a first comparator and a second comparator connected in parallel,
Wherein a first input terminal is connected to one end of the first comparator and a second comparator and a second input terminal is connected to the other end of the first comparator and the second comparator. delete The method according to claim 6,
Wherein one of the position signal and the addition signal is input to a first input terminal of the first comparator and a second input terminal of the second comparator and the other of the position signal and the addition signal is input to a second input of the first comparator Terminal and a first input terminal of the second comparator,
Wherein when the plurality of comparators connected in parallel are grouped into one group, the operation unit receives the comparison signal of the adjacent group of comparators, generates a position signal,
Wherein the integrated circuit is integrated into at least one of a chip of a personal portable terminal and an LCD driving chip, and is integrated with a single chip (ONE-CHIP). delete delete delete delete delete delete delete

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