JP2010176469A - Touch panel device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a "touch panel device" capable of reducing power consumption for applying a reference voltage to an A/D converter. <P>SOLUTION: A reference voltage control means 26 is formed so as to control the voltage value of the reference voltage when the duration of a non-operation state measured by a timing means 27 in the non-operation state reaches the threshold time to be a value lower than the voltage value of the reference voltage when a touch panel 2 is being operated and when the duration of the non-operation state measured by the timing means 27 in the non-operation state does not reach the threshold time. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a touch panel device, and more particularly to an analog touch panel device.

  2. Description of the Related Art Conventionally, a touch panel that allows a user to perform an input operation by bringing an operating body such as a finger into contact has been used as an input device for operating an electronic device such as a vehicle-mounted device.

  Such touch panels include an analog type in which an operation result to the touch panel is input as an analog signal, and a digital type in which an operation result is input as a digital signal. The A / D converter converts an input analog signal into a digital signal in order to detect the coordinates of the operation position of the touch panel (see, for example, Patent Document 1).

  In addition, for an A / D converter used in this type of analog touch panel, a reference voltage is used as a reference voltage for converting an analog signal input from the touch panel into a digital signal (A / D conversion). Applying was done. The A / D converter converts an input analog signal into a digital signal based on the applied reference voltage.

JP 2001-306255 A

  However, conventionally, the operation of the touch panel is not performed, and the reference voltage is applied to the A / D converter even in the state where the detection of the coordinates of the operation position is not required, so that the power consumption increases. Has occurred.

  Therefore, the present invention has been made in view of such problems, and an object of the present invention is to provide a touch panel device that can reduce power consumption associated with application of a reference voltage to an A / D converter. It is.

  In order to achieve the above-described object, a touch panel device according to the present invention includes an analog type touch panel that inputs an analog signal indicating a voltage value corresponding to an operation position, and the analog signal input from the touch panel is converted to the operation position. An A / D converter that converts the signal into a digital signal in order to detect the coordinates, reference voltage application means that applies a reference voltage to the A / D converter, and the reference voltage application means that is applied to the A / D converter. A reference voltage control means for controlling the voltage value of the reference voltage, and a time measuring means for measuring a duration of a no-operation state in which the touch panel is not operated, the reference voltage control means, The continuation measured by the timing means in the no-operation state The voltage value of the reference voltage when the interval reaches a preset threshold time, the duration time measured by the timing means when the touch panel is operated and in the no-operation state is the threshold value. It is characterized in that it is configured to control to a value lower than the voltage value of the reference voltage when the time has not been reached.

  According to such a configuration, the voltage value of the reference voltage can be reduced by the reference voltage control means when the duration of the no-operation state reaches the threshold time, and accordingly, the reference voltage is applied. Power consumption can be reduced.

  Further, the reference voltage control means has reached the threshold time when the voltage value of the reference voltage when the touch panel is operated and the duration time measured by the time measuring means in the no-operation state. It may be formed so as to control the voltage value of the reference voltage to the same value when there is not.

  And according to such a structure, control of a reference voltage can be simplified and the burden of a reference voltage control means can be reduced.

  Furthermore, it comprises a resolution control means for controlling the resolution of the A / D converter, and the resolution control means is configured to control the voltage value of the reference voltage by the reference voltage control means in the no operation state. The resolution of the A / D converter when the continuation time measured by the time reaches the threshold time when the touch panel is operated and the continuation measured by the time measuring means in the non-operation state It may be configured to control to a value lower than the resolution of the A / D converter when the time does not reach the threshold time.

  According to such a configuration, further power saving can be achieved by reducing the resolution of the A / D converter with the resolution control means as the voltage value of the reference voltage decreases.

  Furthermore, the resolution control means reaches the threshold time when the resolution of the A / D converter when the touch panel is operated and the duration time measured by the time measuring means in the non-operation state. In this case, the resolution of the A / D converter in the case where the A / D converter is not used may be controlled to the same value.

  And according to such a structure, control of resolution can be simplified and the burden of the resolution control means can be reduced.

  The touch panel may be an analog resistive film type touch panel.

  According to such a configuration, when the duration of the non-operation state of the analog resistive touch panel reaches the threshold time, the voltage value of the reference voltage can be reduced, and the reference voltage is applied. Power consumption can be reduced.

  According to the present invention, power consumption accompanying application of a reference voltage to the A / D converter can be reduced.

1 is a schematic exploded perspective view showing a touch panel in an embodiment of a touch panel device according to the present invention. In the embodiment of the touch panel device according to the present invention, it is an explanatory diagram for explaining a method for detecting a coordinate of an operation position, where (a) is an X coordinate detection method and (b) is a Y coordinate detection. Explanatory diagram for explaining each method 1 is an overall view showing an embodiment of a touch panel device according to the present invention. The block diagram which shows the internal structure of a microcomputer in embodiment of the touchscreen apparatus which concerns on this invention. The time chart which shows the setting state of the voltage value of the reference voltage according to the voltage value which an analog signal shows in embodiment of the touchscreen device which concerns on this invention The flowchart which shows embodiment of the touchscreen apparatus which concerns on this invention.

  Hereinafter, embodiments of a touch panel device according to the present invention will be described with reference to FIGS. 1 to 6.

  As shown in FIG. 1, the touch panel device 1 in the present embodiment includes an analog resistive film type touch panel 2. The touch panel 2 has two electrode plates 3 and 4 including a fixed electrode plate 3 and a movable electrode plate 4 facing the fixed electrode plate 3 in the upper part of FIG. 4 are arranged with a predetermined gap therebetween via a spacer (not shown).

  As shown in FIG. 1, a fixed-side transparent conductive film 5 made of ITO (indium tin oxide) or the like is formed on the upper surface of a fixed-side substrate (not shown) made of glass or the like. 5 is formed by forming a pair of electrodes 7 and 8 of a positive electrode 7 and a negative electrode 8 that are long in the X direction and made of silver paste or the like at both ends in the Y direction in FIG.

  Further, the movable electrode plate 4 has a movable-side transparent conductive film 10 made of ITO or the like formed on the lower surface of a movable-side substrate (not shown) made of PET or the like, as shown in FIG. 1 is formed by forming a pair of electrodes 11 and 12 of a positive electrode 11 and a negative electrode 12 that are long in the Y direction and made of silver paste or the like at both ends in the X direction.

  Then, the user performs an operation (input operation) of the touch panel 2 by pressing the movable electrode plate 4 from above to bring the fixed-side transparent conductive film 5 and the movable-side transparent conductive film 10 into contact with each other. Is possible.

  That is, the contact point of the transparent conductive films 5 and 10 becomes the operation position P of the touch panel 2, and the touch panel device 1 is configured to detect the X coordinate and the Y coordinate of the operation position P alternately.

Specifically, when detecting the X coordinate of the operation position P, the touch panel device 1 applies a voltage only between the electrodes 11 and 12 of the movable electrode plate 4 as shown in FIG. , The potential gradient generated in the movable transparent conductive film 10 in accordance with the operation of the touch panel 2 is detected through the fixed electrode plate 3. Here, as shown in FIG. 2, the voltage applied between the electrodes 11 and 12 of the movable electrode plate 4 is E [V], and between the operation position P and the positive electrode 11 in the transparent conductive film 10 on the movable side. If the equivalent resistance in the X direction is R _X1 [Ω] and the equivalent resistance in the X direction between the operating position P and the negative electrode 12 in the transparent conductive film 10 on the movable side is R _X2 [Ω], the fixed electrode plate 3 A voltage of {R _X2 / (R _X1 + R _X2 )} × E [V] (hereinafter referred to as X coordinate voltage) is detected. The touch panel device 1 detects the X coordinate corresponding to the X coordinate voltage by, for example, extracting it from a table in which the correspondence relationship between the X coordinate voltage and the X coordinate value is described. Yes. However, the touch panel device 1 detects the X coordinate voltage as a digital quantity through A / D conversion by an A / D converter 20 (see FIG. 3) described later.

When the touch panel device 1 detects the Y coordinate of the operation position P, as shown in FIG. 2B, the touch panel device 1 applies a voltage only between the electrodes 7 and 8 of the fixed electrode plate 3. The potential gradient generated in the transparent conductive film 5 on the fixed side in accordance with the operation 2 is detected through the movable electrode plate 4. Here, as shown in FIG. 2, the voltage applied between the electrodes 7 and 8 of the fixed electrode plate 3 is E [V], and between the operation position P and the positive electrode 7 in the transparent conductive film 5 on the fixed side. When the equivalent resistance in the Y direction is R _Y1 [Ω] and the equivalent resistance in the Y direction between the operating position P and the negative electrode 8 in the transparent conductive film 5 on the fixed side is R _Y2 [Ω], the movable electrode plate 4 A voltage of {R _Y2 / (R _Y1 + R _Y2 )} × E [V] (hereinafter referred to as Y coordinate voltage) is detected. The touch panel device 1 detects the Y coordinate corresponding to the Y coordinate voltage by, for example, extracting it from a table in which the correspondence relationship between the Y coordinate voltage and the Y coordinate value is described. Yes. However, the touch panel device 1 detects this Y coordinate voltage as a digital quantity through A / D conversion by an A / D converter 20 described later.

  Next, FIG. 3 is an overall view of the touch panel device 1 according to the present embodiment. As shown in FIG. 3, the touch panel device 1 includes a power supply device 14 and a microcomputer 15 in addition to the touch panel 2. . In FIG. 3, the touch panel 2 is shown as an equivalent circuit.

  The power supply device 14 selectively applies a voltage for detecting the coordinates of the operation position P between the electrodes 11 and 12 of the movable electrode plate 4 and between the electrodes 7 and 8 of the fixed electrode plate 3. As a configuration for this, the first switch 17 connected to the positive terminal of the power supply device 14 is provided. The first switch 17 includes the positive electrode 11 of the movable electrode plate 4 and the positive electrode of the fixed electrode plate 3. 7 can be selectively connected. The second switch 18 is connected to the ground, and the second switch 18 can be selectively connected to the negative electrode 12 of the movable electrode plate 4 and the negative electrode 8 of the fixed electrode plate 3. Has been. Furthermore, as shown in FIG. 4, the microcomputer 15 has a switch control unit 19 that controls the operations of the first switch 17 and the second switch 18. The switch control unit 19 connects the first switch 17 to the positive electrode 11 of the movable electrode plate 4 and connects the second switch 18 to the negative electrode 12 of the movable electrode plate 4 in order to detect the X coordinate. Thus, application of voltage between the electrodes 11 and 12 of the movable electrode plate 4 by the power supply device 14 is permitted. The switch control unit 19 connects the first switch 17 to the positive electrode 7 of the fixed electrode plate 3 and connects the second switch 18 to the negative electrode 8 of the fixed electrode plate 3 in order to detect the Y coordinate. As a result, application of voltage between the electrodes 7 and 8 of the fixed electrode plate 3 by the power supply device 14 is allowed. The switch control unit 19 performs such control of the switches 17 and 18 for detecting the X coordinate and control of the switches 17 and 18 for detecting the Y coordinate regardless of whether or not the touch panel 2 is operated. It is designed to be performed alternately.

  As shown in FIGS. 3 and 4, the microcomputer 15 includes an A / D converter 20, and the AVREF (Analog Reference Voltage) terminal 22 of the A / D converter 20 is connected to the power supply device 14. A reference voltage is applied. That is, the power supply device 14 functions as reference voltage application means. The reference voltage may be the same voltage as the voltage supplied from the power supply device 14 to the fixed electrode plate 3 and the movable electrode plate 4 of the touch panel 2. In the present embodiment, the power supply device 14 includes a power supply voltage setting circuit 21 that sets the voltage value of the reference voltage in accordance with control of a reference voltage control unit 26 described later. The power supply device 14 may be a known variable voltage power supply.

  Further, as shown in FIG. 3, a third switch 24 is connected to the analog input terminal 23 of the A / D converter 20, and the third switch 24 is a movable electrode under the control of the switch control unit 19. The negative electrode 12 of the plate 4 and the negative electrode 8 of the fixed electrode plate 3 can be selectively connected. That is, the switch control unit 19 connects the third switch 24 to the negative electrode 8 of the fixed electrode plate 3 to detect the X coordinate, so that an analog signal indicating the voltage value of the X coordinate voltage is generated. It is allowed to input from the side to the A / D converter 20 side. In addition, the switch control unit 19 connects the third switch 24 to the negative electrode 12 of the movable electrode plate 4 to detect the Y coordinate, whereby an analog signal indicating the voltage value of the Y coordinate voltage is transferred to the movable electrode plate 4. It is allowed to input from the side to the A / D converter 20 side. The switch control unit 19 controls the third switch 24 for detecting the X coordinate in conjunction with the control of the first switch 17 and the second switch 18 for detecting the X coordinate described above. The control of the third switch 24 for detecting the Y coordinate is performed in conjunction with the control of the first switch 17 and the second switch 18 for detecting the Y coordinate described above. Therefore, the control of the third switch 24 for detecting the X coordinate and the control of the third switch 24 for detecting the Y coordinate are alternately performed regardless of whether or not the touch panel 2 is operated. . Thus, in a non-operation state in which the operation of the touch panel 2 is not performed, an analog signal indicating an X coordinate voltage of 0 [V] and an analog signal indicating a Y coordinate voltage of 0 [V] are A / D converter 20 is alternately input.

  When detecting the X coordinate, the A / D converter 20 uses the reference voltage input to the AVREF terminal 22 as a reference voltage, and an analog signal indicating the reference voltage and the X coordinate voltage input from the fixed electrode plate 3 side. Are compared with each other, the input analog signal is A / D converted into a digital signal for detection of the X coordinate by the microcomputer 15. The microcomputer 15 detects the X coordinate based on the digital amount of the X coordinate voltage indicated by the digital signal obtained by the A / D conversion.

  Further, when detecting the Y coordinate, the A / D converter 20 uses the reference voltage input to the AVREF terminal 22 as a reference voltage to indicate the reference voltage and the Y coordinate voltage input from the movable electrode plate 4 side. By comparing the analog signal with the analog signal, the input analog signal is A / D converted into a digital signal for detection of the Y coordinate by the microcomputer 15. The microcomputer 15 detects the Y coordinate based on the digital amount of the Y coordinate voltage indicated by the digital signal obtained by the A / D conversion.

  Although not shown, such detection results of the X coordinate and the Y coordinate are input to the command execution unit in the operation target device of the touch panel device 1 as a command corresponding to the detection result, and input to the command execution unit. The command will be executed. The command execution unit may be built in the microcomputer 15.

  Furthermore, in the present embodiment, as shown in FIG. 4, the microcomputer 15 includes a reference voltage control unit 26 as a reference voltage control unit. The voltage value of the reference voltage applied to the D converter 20 is controlled.

  The microcomputer 15 has a built-in timer 27 as a timer, and the timer 27 measures the duration of the non-operation state of the touch panel 2 based on the analog signal input from the touch panel 2. It is like that.

  In this embodiment, as shown in FIG. 5A, the reference voltage control unit 26 inputs the analog signal indicating the X coordinate voltage (see FIG. 5B) and the analog signal indicating the Y coordinate voltage. The voltage value of the reference voltage is controlled in accordance with the input state (see FIG. 5C) and the measurement result of the duration of the no-operation state by the time measuring unit 27. When the operation of the touch panel 2 is performed, the value of the X coordinate voltage in FIG. 5B and the value of the Y coordinate voltage in FIG. 5C are alternately greater than 0 [V]. When the touch panel 2 is not operated, both the value of the X coordinate voltage in FIG. 5B and the value of the Y coordinate voltage in FIG. 5C are 0 [V].

  Here, as shown in FIG. 5 (c), the reference voltage control unit 26 sets the threshold time set in advance by the time measuring unit 27 when the operation of the touch panel 2 is performed and in the non-operation state. When the time has not been reached, the power supply voltage setting circuit 21 (in other words, the power supply device) is set so that the voltage value of the reference voltage is set to a preset high voltage side value (+5 [V] in FIG. 5). 14) is controlled.

  On the other hand, when the duration time measured by the time measuring unit 27 reaches the threshold time in the non-operation state, the reference voltage control unit 26 sets the reference voltage value to a preset low voltage side value (FIG. 5). The power supply voltage setting circuit 21 is controlled to be set to +1 [V]).

  That is, the reference voltage control unit 26 determines the voltage value of the reference voltage when the duration time measured by the time measuring unit 27 in the non-operation state reaches the threshold time when the touch panel 2 is operated and when there is no operation. In the operation state, the duration time measured by the time measuring unit 27 is controlled to a value lower than the voltage value of the reference voltage when the threshold time is not reached. In addition, the reference voltage control unit 26 is configured so that the voltage value of the reference voltage when the operation of the touch panel 2 is performed and the duration time measured by the time measuring unit 27 in the non-operation state does not reach the threshold time. The voltage value of the reference voltage is controlled to the same value.

  According to such a configuration, the voltage value of the reference voltage can be reduced when the duration of the no-operation state reaches the threshold time, so that power consumption associated with application of the reference voltage can be reduced. . Further, since the control of the reference voltage by the reference voltage control unit 26 can be simplified, the processing burden on the reference voltage control unit 26 can be reduced.

  As shown in FIG. 5, the reference voltage control unit 26 switches the reference voltage value from the high voltage side value to the low voltage side value and then performs an operation on the touch panel 2. Is configured to return the voltage value of the reference voltage to a value on the high voltage side by controlling the power supply voltage setting circuit 21 (power supply device 14).

  Thereby, when the operation of the touch panel 2 is resumed, the coordinates of the operation position of the touch panel 2 can be detected with high accuracy by applying a reference voltage having a sufficiently high voltage value again.

  In addition to the above configuration, in the present embodiment, the microcomputer 15 includes a resolution control unit 28 as resolution control means, and the resolution control unit 28 has a resolution [bit] of the A / D converter 20. Is to control.

  The resolution control unit 28 is a value on the high resolution side, in which the resolution of the A / D converter 20 is set in advance as the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the high voltage side. (For example, 10 [bit]).

  On the other hand, the resolution control unit 28 controls the resolution of the A / D converter 20 on the low resolution side set in advance as the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the low voltage side. It is controlled to a value (for example, 1 [bit]).

  In other words, the resolution control unit 28 controls the A / D converter when the duration time measured by the time measuring unit 27 reaches the threshold time in the no-operation state as the reference voltage control unit 26 controls the voltage value of the reference voltage. The resolution of 20 is set to a value lower than the resolution of the A / D converter 20 when the touch panel 2 is operated and when the duration time measured by the time measuring unit 27 does not reach the threshold time. It comes to control. Further, the resolution control unit 28 is configured so that the resolution of the A / D converter 20 when the touch panel 2 is operated and the duration time measured by the time measuring unit 27 in the non-operation state does not reach the threshold time. The resolution of the A / D converter 20 is controlled to the same value.

According to such a configuration, the resolution control unit 28 can further reduce power consumption by reducing the resolution of the A / D converter 20 as the voltage value of the reference voltage decreases. In addition, since the resolution control of the A / D converter 20 by the resolution control unit 28 can be simplified, the processing load on the resolution control unit 28 can be reduced.
The resolution control unit 28 switches the resolution of the A / D converter 20 from a value on the high resolution side to a value on the low resolution side, and then the voltage value of the reference voltage is restored to the value on the high voltage side. Along with this, the resolution of the A / D converter 20 is restored to the value on the high resolution side.

  Thereby, when the operation 2 of the touch panel is resumed, the coordinates of the operation position of the touch panel 2 can be detected with high accuracy by setting the resolution of the A / D converter 20 to a sufficiently high value again.

  Next, the effect | action of this embodiment is demonstrated using the flowchart of FIG.

  For convenience, the operation of the touch panel 2 is performed in the initial state, and the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the high voltage side (see FIG. 5A). In addition, it is assumed that the resolution of the A / D converter 20 is controlled to a value on the high resolution side by the control of the resolution control unit 28.

  From the initial state, first, in step 1 (ST1) in FIG. 6, whether or not the reference voltage control unit 26 has entered the no-operation state based on the voltage value indicated by the analog signal input from the touch panel 2 side. If it is determined that there is no operation, the process proceeds to step 2 (ST2). If it is not, the process returns to step 1 (ST1). When returning to step 1 (ST1), the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the high voltage side in the initial state, and accordingly, the resolution control unit 28 also controls the A / The resolution of the D converter 20 is controlled to a value on the high resolution side in the initial state.

  Next, in step 2 (ST2), the time measuring unit 27 starts measuring the duration of the no-operation state.

  Next, in step 3 (ST3), the reference voltage control unit 26 determines whether or not the measurement result of the time measuring unit 27 has reached the threshold time. If the threshold time has been reached, step 4 (ST4) If the threshold time has not been reached, the process proceeds to step 9 (ST9).

  In step 4 (ST4), the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the low voltage side, and the process proceeds to step 5 (ST5).

  On the other hand, in step 9 (ST9), the reference voltage control unit 26 determines whether or not the operation of the touch panel 2 has been performed based on the voltage value indicated by the analog signal input from the touch panel 2 side. If so, the process returns to step 1 (ST1), and if it remains in the no-operation state, the process proceeds to step 10 (ST10).

  Here, when returning from step 9 (ST9) to step 1 (ST1), the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the high voltage side while maintaining the initial state. The resolution control unit 28 also controls the resolution of the A / D converter 20 to a value on the high resolution side in the initial state.

  In step 10 (ST10), the reference voltage control unit 26 determines whether or not the power of the touch panel device 1 is turned off. When the touch panel device 1 is turned off, the processing is terminated and turned off. If not, the process returns to step 3 (ST3).

  Next, in step 5 (ST5), the resolution controller 28 controls the resolution of the A / D converter 20 to a value on the low resolution side, and proceeds to step 6 (ST6).

  Next, in step 6 (ST6), the reference voltage control unit 26 determines whether or not the operation of the touch panel 2 has been performed based on the voltage value indicated by the analog signal input from the touch panel 2 side. If so, the process proceeds to step 7 (ST7), and if it remains in the no-operation state, the process proceeds to step 11 (ST11).

  Next, in step 7 (ST7), the reference voltage control unit 26 controls the voltage value of the reference voltage again to a value on the high voltage side, and proceeds to step 8 (ST8).

  On the other hand, in step 11 (ST11), the reference voltage control unit 26 determines whether or not the power supply of the touch panel device 1 is turned off. If it is turned off, the process is terminated and turned off. If not, the process returns to step 6 (ST6).

  Next, in step 8 (ST8), the resolution controller 28 controls the resolution of the A / D converter 20 to a value on the high resolution side again, and the process returns to step 1 (ST1).

  As described above, according to the present embodiment, the reference voltage control unit 26 controls the voltage value of the reference voltage to a value on the low voltage side when the duration of the no-operation state reaches the threshold time. Therefore, power consumption associated with application of the reference voltage can be reduced.

  In addition, this invention is not limited to embodiment mentioned above, A various change is possible as needed.

  For example, the present invention may be applied to an analog capacitive coupling type touch panel.

DESCRIPTION OF SYMBOLS 1 Touch panel device 2 Touch panel 14 Power supply device 20 A / D converter 26 Reference voltage control part 1 Timekeeping part

Claims (5)

An analog touch panel that inputs an analog signal indicating a voltage value according to the operation position;
An A / D converter that converts the analog signal input from the touch panel into a digital signal to detect the coordinates of the operation position;
A reference voltage applying means for applying a reference voltage to the A / D converter;
Reference voltage control means for controlling the voltage value of the reference voltage applied to the A / D converter by the reference voltage application means;
A time measuring means for measuring a duration of a no-operation state in which the touch panel is not operated,
The reference voltage control means operates the touch panel to determine the voltage value of the reference voltage when the duration time measured by the time measuring means in the no-operation state has reached a preset threshold time. And when the duration time measured by the time measuring means in the no-operation state does not reach the threshold time, the voltage is controlled to be lower than the voltage value of the reference voltage. Touch panel device. The reference voltage control means is configured such that the voltage value of the reference voltage when the touch panel is operated and the duration time measured by the time measuring means in the no operation state does not reach the threshold time. The touch panel device according to claim 1, wherein the touch panel device is configured to control the voltage value of the reference voltage in the same value. A resolution control means for controlling the resolution of the A / D converter;
The resolution control unit is configured to control the A when the duration time measured by the time measuring unit reaches the threshold time in the no-operation state in accordance with the control of the voltage value of the reference voltage by the reference voltage control unit. The resolution of the A / D converter when the touch panel is operated and when the duration time measured by the time measuring means in the no-operation state has not reached the threshold time The touch panel device according to claim 1, wherein the touch panel device is formed to be controlled to a lower value. The resolution control unit is configured such that the resolution of the A / D converter when the touch panel is operated and the duration time measured by the time measuring unit in the no-operation state does not reach the threshold time. The touch panel device according to claim 3, wherein the touch panel device is configured to control the resolution of the A / D converter in the same value. The touch panel device according to any one of claims 1 to 4, wherein the touch panel is an analog resistive film type touch panel.

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