JP7026662B2 - Touch panel drive device, touch panel device - Google Patents

Description

The present invention relates to a touch panel drive device and a touch panel device, and more particularly to a technique used for touch panel operation detection.

Various technologies are known for touch panels, and in Patent Document 1 below, two sets of signal lines (electrodes) of two sets (a pair of transmission signal lines and a pair of reception signal lines) are simultaneously sensed to detect the touch operation position. Sensing technology that improves resolution by doing so is disclosed.
Further, Patent Document 2 below discloses a so-called single-layer structure in which a portion where electrodes intersect is not provided in the electrode wiring in the X and Y directions.

Japanese Unexamined Patent Publication No. 2014-219961 Japanese Unexamined Patent Publication No. 2010-182277

It is important to maintain or improve the sensing accuracy of the touch panel. Then, in order to detect the operation, the signal line of the touch panel is scanned, but in the case of the capacitive touch panel, the signal voltage from the signal line according to the capacitance change due to the touch operation at the time of scanning is performed. Changes and differences will be detected.
Here, in the case of the method of detecting the touch operation by comparing the signals of the pair of received signal lines, the signal balance in the non-touch state is important. However, when the wiring resistance and parasitic capacitance at a specific location differ from the surrounding environment due to the panel lead wiring arrangement of the received signal line and the position on the wiring pattern, this external factor is a pair of received signal lines in differential detection ( A potential difference may be generated between the receiving electrodes), causing a bias in the signal value. Then, the detection accuracy is lowered.
Therefore, the present invention proposes a technique capable of suppressing a decrease in detection accuracy even due to such an event.

The touch panel drive device according to the present invention is a touch panel drive device that sequentially scans a touch panel to select a pair of adjacent transmission signal lines and a pair of adjacent reception signal lines. Then, the receiving circuit that generates the detection value of the touch panel operation by receiving and comparing each received signal whose waveform changes due to the capacitance change accompanying the operation from the pair of received signal lines of the touch panel is selected by the scanning. A correction voltage transmission circuit for outputting a correction voltage to be transmitted to a reception signal line other than the pair of reception signal lines corresponding to the pair of reception signal lines to be in a state is provided.
Further, the touch panel device according to the present invention is composed of the above touch panel drive device and a touch panel.
In the touch panel device, a state in which the pair of received signal lines are not balanced at the time of non-touch may occur, which may make correct touch detection impossible. In order to deal with this, it is possible to apply a correction voltage for the received signal value to a pair of received signal lines.

In the touch panel drive device described above, in the process of scanning, a pair of received signal lines are sequentially selected by a multiplexer and connected to the receiving circuit, and received signals other than the pair of received signal lines to be selected. It is conceivable that the wire is selected by the multiplexer and connected to the correction voltage transmission circuit.
That is, the multiplexer selects a pair of received signal lines to be connected to the receiving circuit so that the correction voltage is applied to the other received signal lines.

In the touch panel drive device described above, it is conceivable that the received signal line adjacent to the received signal line selected in the scanning can be selected as the received signal line to which the correction voltage is transmitted.
That is, when a pair of received signal lines is selected by scanning, a correction voltage can be applied to the received signal line adjacent to any of the received signal lines.

In the touch panel drive device described above, it is conceivable that a received signal line not adjacent to the received signal line selected in the scanning can be selected as the received signal line to which the correction voltage is transmitted.
That is, when a pair of received signal lines is selected by scanning, the received signal lines that are not adjacent to any of the received signal lines can be used for applying the correction voltage.

In the touch panel drive device described above, one received signal line other than the pair of received signal lines selected by the scanning is short-circuited to one of the pair of received signal lines, and the one received signal line is defined as the one. It may be possible to transmit the correction voltage to yet another reception signal line.
That is, when a pair of received signal lines is selected by scanning, the other received signal line is made to function as one of the pair of received signal lines in the selected state. Then, the correction voltage can be transmitted to, for example, another reception signal line adjacent to one reception signal line.

In the touch panel drive device described above, for each pair of the pair of transmission signal lines and the pair of reception signal lines selected in the scanning, at least the correction voltage and the reception signal line of the correction voltage transmission destination are stored according to the correction table. It is conceivable that the correction voltage is transmitted.
Calibration is performed in advance to create a correction table in which an appropriate correction operation (correction voltage value and correction voltage transmission destination) is determined for each pair of a pair of transmission signal lines and a pair of reception signal lines. At the time of actual operation, it operates according to the correction table.

According to the present invention, by applying a correction voltage to the received signal line in the selected state, it is possible to correct the pair of received signal lines so that the signal levels at the time of non-touch are balanced. As a result, a signal level difference corresponding to the touch is generated at the time of touch detection, and an appropriate touch detection operation can be realized.

It is a block diagram of the touch panel apparatus of embodiment of this invention. It is explanatory drawing of the signal line structure of the touch panel of embodiment. It is explanatory drawing of the sensing operation of embodiment. It is explanatory drawing of the capacity part for measurement of embodiment. It is a flowchart of the sensing operation procedure of embodiment. It is explanatory drawing of the correction voltage transmission to the adjacent signal line of embodiment. It is explanatory drawing of the correction voltage transmission to the non-adjacent signal line of embodiment. It is explanatory drawing of the short circuit of the non-adjacent signal line and the correction voltage transmission of embodiment. It is explanatory drawing of the correction table of embodiment. It is a flowchart of the sensing process including the correction operation of embodiment.

Hereinafter, embodiments of the present invention will be described in the following order.
<1. Touch panel device configuration>
<2. Sensing operation>
<3. Sensing operation including correction operation>
<4. Summary and modification>

<1. Touch panel device configuration>
FIG. 1 shows a configuration example of the touch panel device 1 according to the embodiment.
The touch panel device 1 is mounted as a user interface device in various devices. Here, various devices are assumed to be, for example, electronic devices, communication devices, information processing devices, manufacturing equipment, machine tools, vehicles, aircraft, building equipment, and other equipment in a wide variety of fields. The touch panel device 1 is adopted as an operation input device used for user operation input in these various equipment products.
FIG. 1 shows a touch panel device 1 and a product-side MCU (Micro Control Unit) 90, and the product-side MCU 90 shows a control device in a device to which the touch panel device 1 is mounted. The touch panel device 1 performs an operation of supplying information on the user's touch panel operation to the product side MCU 90.

The touch panel device 1 includes a touch panel 2 and a touch panel drive device 3.
The touch panel drive device 3 has a sensor IC (Integrated Circuit) 4 and an MCU 5.
The touch panel drive device 3 is connected to the touch panel 2 via the touch panel side connection terminal unit 31. The touch panel drive device 3 drives (sensing) the touch panel 2 via this connection.
When mounted on a device as an operation input device, the touch panel drive device 3 is connected to the product side MCU 90 via the product side connection terminal unit 32. Through this connection, the touch panel drive device 3 transmits the sensed operation information to the MCU 90 on the product side.

The sensor IC 4 in the touch panel drive device 3 includes a transmission circuit 41, a reception circuit 42, a multiplexer 43, an interface register circuit 44, a power supply circuit 45, and a correction voltage transmission circuit 46.

The transmission circuit 41 of the sensor IC 4 outputs a transmission signal to the terminal on the touch panel 2 selected by the multiplexer 43. Further, the receiving circuit 42 receives a signal from the terminal on the touch panel 2 selected by the multiplexer 43, and performs necessary comparison processing and the like.

FIG. 2 schematically shows the connection state of the transmission circuit 41, the reception circuit 42, the correction voltage transmission circuit 46, the multiplexer 43, and the touch panel 2.
In the touch panel 2, n transmission signal lines 21-1 to 21-n as electrodes on the transmission side are arranged on a panel plane forming a touch surface.
Similarly, on the panel plane, m reception signal lines 22-1 to 22-m as electrodes on the reception side are arranged.
When the transmission signal lines 21-1 ... 21-n and the reception signal lines 22-1 ... 22-m are not particularly distinguished, they are collectively referred to as "transmission signal line 21" and "reception signal line 22". ..

The transmission signal lines 21-1 ... 21-n and the reception signal lines 22-1 ... 22-m may be arranged intersecting each other as shown in the figure, or may be arranged as a so-called single layer structure. It may be arranged so as not to cause an intersection as in Patent Document 2 described above. In any case, the touch operation surface is formed within the range in which the transmission signal line 21 and the reception signal line 22 are arranged, and the operation position is detected by the capacitance change during the touch operation.
The figure illustrates only a part of the capacitance generated between the transmission signal line 21 and the reception signal line 22 (capacities C22, C23, C32, C33), but the transmission signal line 21 and the reception signal are applied to the entire touch operation surface. There is a capacitance generated between the lines 22 (for example, a capacitance at the crossing position), and the position where the capacitance change is generated by the touch operation is detected by the receiving circuit 42.

The transmission circuit 41 outputs a transmission signal to the transmission signal lines 21-1 ... 21-n selected by the multiplexer 43. In the present embodiment, the multiplexer 43 performs scanning by selecting two adjacent transmission signal lines 21 at each timing.
The receiving circuit 42 receives the received signal from the received signal lines 22-1 ... 22-m selected by the multiplexer 43. In the present embodiment, the multiplexer 43 selects two adjacent reception signal lines 22 at each timing.
The sensing operation by the transmission circuit 41 and the reception circuit 42 will be described later.

The correction voltage transmission circuit 46 applies a correction voltage to the required reception signal line 22 via the multiplexer 43. Specifically, the multiplexer 43 selects a reception signal line that is not selected for scanning, which is different from the pair of reception signal lines 22 that are selected by scanning, as a correction voltage transmission destination. Is connected to the correction voltage transmission circuit 46.
The operation of applying the correction voltage by the correction voltage transmission circuit 46 will be described in detail later.

It will be described back to FIG. Various setting information for the transmission circuit 41, the multiplexer 43, the reception circuit 42, the power supply circuit 45, and the correction voltage transmission circuit 46 is written in the interface register circuit 44 of the sensor IC 4 by the MCU 5.
The operation of the transmission circuit 41, the multiplexer 43, the reception circuit 42, the power supply circuit 45, and the correction voltage transmission circuit 46 is controlled by the setting information stored in the interface register circuit 44, respectively.
Further, the interface register circuit 44 stores the detection value (also referred to as “RAW value” in the description) detected by the reception circuit 42 so that the MCU 5 can acquire it.

The power supply circuit 45 generates a drive voltage AVCC and supplies it to the transmission circuit 41, the reception circuit 42, and the correction voltage transmission circuit 46. As will be described later, the transmission circuit 41 applies a pulse using the drive voltage AVCC to the transmission signal line 21 selected by the multiplexer 43.
The receiving circuit 42 also applies the drive voltage AVCC to the receiving signal line 22 selected by the multiplexer 43 during the sensing operation.
The correction voltage transmission circuit 46 applies the drive voltage AVCC to the reception signal line 22 selected by the multiplexer 43.

The MCU 5 sets and controls the sensor IC 4. Specifically, the MCU 5 controls the operation of each part of the sensor IC 4 by writing necessary setting information to the interface register circuit 44.
Further, the MCU 5 acquires the RAW value from the receiving circuit 42 by reading it from the interface register circuit 44. Then, the MCU 5 performs a coordinate calculation using the RAW value, and performs a process of transmitting the coordinate value as the user's touch operation position information to the product side MCU 90.
In FIG. 1, the RAM area, the ROM area, the non-volatile storage area, and the like are collectively shown as the memory 5a in the MCU 5. This memory 5a is used to store the setting information given to the interface register circuit 44. Further, the memory 5a also uses the detected RAW value and the coordinate value as the touch operation position information corresponding to the detected RAW value as a temporary storage area.

<2. Sensing operation>
The sensing operation by the touch panel device 1 having the above configuration will be described.
First, the operation of the transmission circuit 41 and the reception circuit 42 with respect to the touch panel 2 will be described with reference to FIG. The figure shows two transmission signal lines 21-2 and 21-3 and two reception signal lines 22-2 and 22-3 on the touch panel 2.
In the case of the present embodiment, the transmission circuit 41 and the reception circuit 42 transmit and receive two adjacent transmission and reception signals to the transmission signal line 21 and the reception signal line 22 as shown in FIG. By going, the touch operation is detected. That is, two × 2 lines of a pair of transmission signal lines 21 and a pair of reception signal lines 22 are used as basic cells, and detection scanning is sequentially performed in cell units. In FIG. 3, the part of the one cell is shown.

The transmission circuit 41 outputs the drive voltage AVCC1 from the drivers 411 and 412 to the two transmission signal lines 21 (21-2, 21-3 in the case of the figure). That is, the transmission signals T + and T-, which are the outputs of the drivers 411 and 412, are supplied to the transmission signal lines 21-2 and 21-3 selected by the multiplexer 43.
The drive voltage AVCC 1 is a drive voltage AVCC itself generated by the power supply circuit 45 of FIG. 1 or a voltage based on the drive voltage AVCC.
In this case, in the transmission circuit 41, the transmission signal T + from the driver 411 has an idle (Idle) period as a low level (hereinafter referred to as “L level”) as shown in the figure. For example, 0V. Then, during the subsequent active period, the level is set to high level (hereinafter referred to as "H level"). In this case, specifically, the drive voltage AVCC1 is applied as the H level signal.
Further, in the transmission circuit 41, the transmission signal T- from the other driver 412 has an idle period of H level (application of drive voltage AVCC1) and a subsequent active period of L level.
Here, the idle period is a period for stabilizing the potentials of the received signals R + and R-, and the active period is a period for sensing the potential changes of the received signals R + and R-.

During this idle period and active period, the receiving circuit 42 receives the received signals R + and R- from the two received signal lines 22 (22-3, 22-2 in the figure) selected by the multiplexer 43.
The receiving circuit 42 includes a comparator 421, a reference capacitance unit 422, a switch 423, 425, a measurement capacitance unit 424, and an arithmetic control unit 426.
The received signals R + and R− from the two received signal lines 22 are received by the comparator 421. The comparator 421 compares the potentials of the received signals R + and R-, and outputs the comparison result to the arithmetic control unit 426 at the H level or the L level.

A drive voltage AVCC2 is applied to one end of a capacitor constituting the reference capacitance portion 422. The drive voltage AVCC 2 is a voltage based on the drive voltage AVCC itself generated by the power supply circuit 45 of FIG. 1 or the drive voltage AVCC. The other end of the capacitor constituting the reference capacitance portion 422 is connected to the + input terminal of the comparator 421 via the terminal Ta of the switch 423.
Further, a drive voltage AVCC2 is applied to one end of the measurement capacitance unit 424. The other end of the measuring capacitance unit 424 is connected to the − input terminal of the comparator 421 via the terminal Ta of the switch 425.

For switches 423 and 425, the terminal Ti is selected during the idle period. Therefore, during the idle period, the + input terminal (received signal line 22-3) and-input terminal (received signal line 22-2) of the comparator 421 are connected to the ground, and the received signals R + and R- become ground potentials.
For switches 423 and 425, the terminal Ta is selected during the active period. Therefore, during the active period, the drive voltage AVCC2 is applied to the + input terminal (received signal line 22-3) and-input terminal (received signal line 22-2) of the comparator 421.

In FIG. 3, the waveforms of the received signals R + and R− when the cell is in the non-touch state are shown by solid lines. In the idle period, the switches 423 and 425 select the terminal Ti, so that the received signals R + and R− are stabilized at a certain potential (ground potential).
During the active period, the switch 423 and 425 select the terminal Ta, so that the drive voltage AVCC2 is applied to the received signal lines 22-3 and 22-2. As a result, the potentials of the received signals R + and R− increase by ΔV. In the non-touch state, this potential increase of ΔV occurs in both the received signals R + and R−.
On the other hand, on the transmission circuit 41 side, during the active period, the transmission signal T + rises and the transmission signal T− falls as described above. As a result, when there is a touch operation, the degree of potential increase of the received signals R + and R− changes.
If the A1 position that affects the capacitance C22 is touched, the potential of the received signal R− rises by ΔVH as shown by the broken line during the active period.
If the A2 position where the capacitance C32 changes is touched, the potential of the received signal R− rises by ΔVL indicated by the broken line during the active period.
As described above, the potential change amount of the received signal R− becomes larger or smaller than the potential change amount (ΔV) of the received signal R + depending on the touch operation position with respect to the cell.
The comparator 421 will compare such received signals R + and R−.

The potential difference itself of the received signals R + and R- changing in this way may be output as a RAW value (detection result), but in the present embodiment, the receiving circuit 42 is received by the arithmetic control unit 426. The setting of the measurement capacitance unit 424 is changed so that the voltage balance of the signals R + and R- can be obtained, and the RAW value is obtained.
The arithmetic control unit 426 performs on / off of switches 423 and 425 and switching of the capacity value of the measurement capacity unit 424 according to the setting information written in the interface register circuit 44. Further, the output of the comparator 421 is monitored, and the RAW value is calculated by the process described later. The RAW value calculated by the arithmetic control unit 426 is written to the interface register circuit 44 so that the MCU 5 can acquire it.

The measurement capacitance unit 424 indicated by the symbol of the variable capacitor in FIG. 3 is composed of a plurality of capacitance units CM (CM0 to CM7) and switches SW (SW0 to SW7) as shown in FIG. 4, for example.
Note that FIG. 4 shows an equivalent circuit in a state where the switches 423 and 425 are connected to the terminal Ta (active period), and the switches 423 and 425 are not shown.
The capacitance units CM0 to CM7 are connected in parallel between the potential of the drive voltage AVCC2 and the-input terminal of the comparator 421. Further, switches SW0 to SW7 are connected in series to each of the capacitance units CM0 to CM7. That is, by turning on / off the switches SW0 to SW7, the capacitance part CM that affects the received signal R- can be changed.
Further, the switches SW0 to SW7 are each configured by using a switch element such as a FET (Field effect transistor), but a plurality of switch elements may be provided as one switch SW.

The capacity values of the capacity units CM0 to CM7 are, for example, capacity units CM0 = 2fF (femtofarad), CM1 = 4fF, CM2 = 8fF, CM3 = 16fF, CM4 = 32fF, CM5 = 64fF, CM6 = 128fF, CM7 = 256fF. Will be done.
In FIG. 4, each of the capacitors CM0 to CM7 is composed of one capacitor, but all or part of each of the capacitors CM0 to CM7 is composed of a plurality of capacitors, and the combined capacitance is the same as the above capacitance value. It may be.
The capacitance units CM0 to CM7 are selected by 8-bit values of bits "0" to "7". The capacitance unit CM0 and the switch SW0 function as a bit “0”, the capacitance unit CM1 and the switch SW1 function as a bit “1”, and the capacitance unit CM7 and the switch SW7 function as a bit “7”.
Then, a capacity setting value from 0 (= "0000000000") to 255 (= "111111111") is given as an 8-bit value. The capacitance setting value is one of the setting information written by the MCU 5 to the interface register circuit 44.
In the receiving circuit 42, the switches SW0 to SW7 are turned on / off according to the 8-bit capacity setting value. That is, the switches SW0 to SW7 are turned off when the corresponding bit is "0" and turned on when the corresponding bit is "1". As a result, the total capacity value of the measurement capacity unit 424 is changed in 256 steps in the range of 0fF to 510fF.

On the other hand, the capacitance value of the capacitor of the reference capacitance section 422 on the reception signal R + side is, for example, 256 fF.

As described above, the degree of potential increase of the waveform of the received signal R- in the active period changes depending on the presence / absence and position of the touch. It becomes larger or smaller than the waveform rise degree (ΔV) of the received signal R +.
In the configuration of FIG. 4, the degree of potential increase of the waveform of the received signal R- can be changed by changing the capacity set value of the measuring capacity unit 424, for example, the measuring capacity equivalent to that of the received signal R +. The capacity setting value of the unit 424 can be found.
For example, assuming that the waveform Sg1 shown by the broken line of the received signal R- in FIG. 4 is in the initial state, if the capacity of the measuring capacitance unit 424 is reduced, the received signal R- becomes smaller than the waveform Sg1 like the waveform Sg2. .. Further, if the capacity of the measuring capacity unit 424 is increased, the received signal R- becomes larger than the waveform Sg1 like the waveform Sg3.
That is, the capacity setting value of the measurement capacitance unit 424 when the voltage levels of the received signals R + and R− are the same in the comparator 421 is equivalent to the value corresponding to the voltage change of the received signal R− due to the touch. Therefore, the capacity setting value of the measurement capacity unit 424 is changed while observing the output of the comparator 421, and the capacity setting value at which the voltages of the received signals R + and R- during the active period are the same is searched for. Then, the searched capacity setting value can be used as the RAW value as the sensing information of the touch operation.

The specific procedure of the above sensing operation will be described with reference to FIG. FIG. 5 shows processing mainly performed by the transmission circuit 41 and the reception circuit 42 based on various setting information written by the MCU 5 to the interface register circuit 44.
In FIG. 5, the loop processing of steps S100 to S109 shows a sensing procedure for one cell (a set of two transmission signal lines 21 and two reception signal lines 22). By the time the RAW value is obtained, the capacity setting value takes 8 different values (changed 7 times from the initial state).

In step S100, the variable n is first set to n = 7 as an initial value. Further, the receiving circuit 42 sets the capacity value of the measurement capacity unit 424 to 256 fF based on the instruction (capacity set value) of the MCU 5. That is, the capacity setting value = 128 (= 1000000), and only the switch SW7 is turned on because only the bit “7” is “1”.

In step S101, the idle period is set.
In the transmission circuit 41, the transmission signal T + from the driver 411 is the L level, and the transmission signal T- is the H level (= drive voltage AVCC1).
In the receiving circuit 42, the switches 423 and 425 are connected to the terminal Ti. As a result, the + input terminal and the-input terminal of the comparator 421 are connected to the ground.

Next, in step S102, the idle period is switched to the active period after a predetermined period elapses.
In the transmission circuit 41, the transmission signal T + from the driver 411 is H level (= drive voltage AVCC1), and the transmission signal T- from the driver 412 is L level.
In the receiving circuit 42, the switches 423 and 425 are connected to the terminal Ta. As a result, the + input terminal of the comparator 421 is connected to the drive voltage AVCC2 via the reference capacitance unit 422, and the-input terminal is connected to the drive voltage AVCC2 via the measurement capacitance unit 424.

During the active period, the received signals R + and R- increase by ΔV, but the transmitted signal T + rises and the transmitted signal T- falls, so that the received signal R according to the presence / absence of a touch operation on the cell being detected and the touch operation position. -A change occurs (the amount of increase is ΔVH or ΔVL).
In step S103, the comparator 421 compares the received signals R + and R− and outputs the comparison result. From the comparator 421, an H level output is obtained if (received signal R +)> (received signal R−), and an L level output is obtained if (received signal R +) <(received signal R−).

In step S104, the processing is branched according to the output of the comparator 421.
If the output of the comparator 421 is H level, the capacitance of the measurement capacitance unit 424 is switched in step S105. In this case, the switch of the bit "n-1" is turned on while the switch of the bit "n" is kept on.
Until then, when the capacity setting value = "10000000" and only the bit "7" was turned on in the initial state as described above, the capacity setting value = "11000000" was subsequently set and the bit "7" and the bit "6" were turned on. Is turned on. That is, the switches SW7 and SW6 are turned on, and the capacity value of the measurement capacity unit 424 is 384fF.
If the variable n> 0 in step S107, the variable n is decremented in step S108 and the process returns to step S101. That is, after increasing the capacity of the measurement capacity unit 424, the operation during the idle period and the active period is performed to confirm the output of the comparator 421.

If the output of the comparator 421 is L level in step S104, the capacity of the measurement capacitance unit 424 is switched in step S106. In this case, the switch of the bit "n" is turned off and the switch of the bit "n-1" is turned on.
If the capacity setting value = "10000000" and only the bit "7" is turned on in the initial state, then the capacity setting value = "01000000" is set and the bit "7" is turned off and the bit "6" is turned on. Is turned on. That is, the switch SW7 is turned off, the switch SW6 is turned on, and the capacity value of the measurement capacity unit 424 is 128 fF.
If the variable n> 0 in step S107, the variable n is decremented in step S108 and the process returns to step S101. That is, after reducing the capacity of the measurement capacity unit 424, the operation during the idle period and the active period is performed to confirm the output of the comparator 421.

By performing this process until the variable n = 0, the capacity setting value when the voltage value in the active period of the received signal R− and the voltage value in the active period of the received signal R + are balanced is determined.
Since the bit "n-1" does not exist in steps S105 and S106 when the variable n = 0, the processing of the bit "n-1" is not performed.
If the variable n = 0 in step S107, the process proceeds to step S109, and the receiving circuit 42 calculates the RAW value. This is a process of taking the sum of the powers of the bits of the switch SW that are turned on in the measurement capacitance unit 424. For example, if the switches SW5, SW3, and SW2 were finally turned on, ²⁵ +2 ³ +2 ² = 44, and the RAW value = 44.

The RAW value thus obtained is acquired by the MCU 5 as a detection value of one cell via the interface register circuit 44.
The processing of FIG. 5 is similarly performed for each cell (a set of two transmission signal lines 21 and two reception signal lines 22) on the touch panel 2, and a RAW value is obtained.
The MCU 5 acquires the RAW value for each cell, calculates the coordinate of the touch operation position, and transmits the obtained coordinate value to the MCU 90 on the product side.

It was shown that in step S101, the correction voltage stop process is performed as the setting of the idle period, and in step S102, the correction voltage application process is performed when the active period is reached. This will be described later.

In the present embodiment, as the sensing operation as described above, by taking the difference between the received signals R + and R-, the acquired RAW value can be made less likely to be affected by the external environment, and the touch operation can be performed. Detection accuracy can be improved.
In particular, when not touched, the potentials of the received signals R + and R-are balanced, and the potentials of the received signals R + and R- are different due to the capacitance change due to the touch. The capacity of the measurement capacity unit 424 is sequentially changed to search for a capacity value in which the received signals R + and R- are balanced, and the RAW value is obtained from the capacity setting value for which the capacity value is specified. As a result, the difference between the received signals R + and R- caused by the capacitance change due to the touch operation can be accurately detected.

There are mainly two reasons for charging the selected reception signal line 22 by applying the drive voltage AVCC2 from the reception circuit 42.
One is the situation when the touch panel 2 has a single layer structure. In the case of the single layer structure, in the non-touch state, almost no capacitance is generated between the transmission signal line 21 and the reception signal line 22. That is, the space between the transmission signal line 21 and the reception signal line 22 (between the electrodes) is in an insulated state. However, even in the non-touch state, it is necessary to make the received signal waveform rise during the active period. For this reason, by transmitting the drive voltage AVCC2, the above-mentioned sensing operation can be performed satisfactorily even in the case of a single layer.
Another reason is not limited to single layers. In the above sensing method, the potential increase width of the received signal R- is seen from the time when the active period is entered, but it is also desired to understand the influence of the falling edge of the transmitted signal T-. That is, it is necessary to observe the potential increase of ΔVL shown by the broken line in FIG. If the potentials of the received signals R + and R- in the non-touch state during the active period are 0 V, the potential of the received signal R- becomes a negative value when affected by the falling edge, and is handled by the receiving circuit 42. It will be difficult. Therefore, the potential of the received signal R- is raised so as not to be 0 V or less, and the drive voltage AVCC2 is applied to facilitate the easy and appropriate observation of the potential of the received waveform due to the influence of the falling edge of the transmitted signal T-. is doing.

<3. Sensing operation including correction operation>
Based on the above basic operation, the sensing operation including the correction operation will be described.
As described above, the RAW value is detected in the range of, for example, "0" to "255". In this case, the reference capacitance unit 422 on the received signal R + side is set to 256 fF, that is, it is always fixed to the center value "128" as the RAW value, and normally, the signal value of the pair of received signal lines 22 in the non-touch state. Takes a state of being balanced to the center value "128".
That is, in the non-touch state, as shown by the solid lines in FIGS. 3 and 4, the received signals R + and R-are balanced in the state where the potential rise of ΔV occurs during the active period.

On the other hand, depending on the panel lead wiring arrangement and the position of the sensor pattern (wiring pattern of the transmission circuit 41 and the reception signal line 22), the reception signal values of the pair of reception signal lines 22 may not be balanced to "128" even in the non-touch state. It may occur.
For example, when the wiring resistance or parasitic capacitance at a specific location differs from the surrounding environment due to the panel lead wiring arrangement or wiring pattern position, this external factor causes a potential difference between the comparison electrodes in differential detection, resulting in a bias in the signal value. Is thought to occur.
When the potential difference between the pair of received signal lines 22 becomes very large and exceeds the range of the received signal value, it is considered that the pair is completely biased to the maximum value or the minimum value of the range such as "0" or "255".

In this way, when the received signal value in the non-touch state is touched in a state of being biased toward the upper limit or the lower limit of the range, the received signal value reaches the maximum value or the minimum value of the range during the signal change due to the touch. Therefore, it becomes impossible to detect the accurate amount of change due to touch.
In particular, when the received signal value is already at the maximum value or the minimum value of the range in the initial stage of the non-touch state, no change in the signal can be obtained even if the touch is made.

If the amount of change in the received signal value that should be originally obtained by touch operation is not sufficiently obtained due to the bias in the initial state, it will not be possible to obtain the change in the signal with respect to the movement of the finger, and the accuracy and resolution of coordinate detection will be improved. It will drop.
This phenomenon tends to occur frequently in cells at edges and corners where the sensor pattern is arranged differently from the center. It may also occur in cells near the flexible wiring board where the lead wiring is concentrated.

Therefore, in the present embodiment, in order to reduce or eliminate the adverse effect of the bias in the received signal value in such a non-touch state, a correction operation is performed so that the received signal value is balanced in the vicinity of the center value. conduct.
Specifically, a reception signal line 22 different from the pair of reception signal lines 22 selected at the time of scanning is set as the correction voltage transmission channel, and a predetermined correction voltage is applied to the reception signal line 22.
At this time, since there is a parasitic capacitance between the reception signal line 22 set as the correction voltage transmission destination and one of the pair of reception signal lines 22 used for scanning, scanning is performed through this parasitic capacitance. A voltage can be applied to the received signal line 22 inside.
In this way, by applying a voltage to the received signal line 22 being scanned via the parasitic capacitance, the balance of the received signal values R + and R- in the pair of received signal lines 22 being scanned (balance in the non-touch state). ) Can be taken.

In order to realize this, the multiplexer 43 sequentially selects the reception signal line 22 of the correction voltage transmission destination during scanning.

An example is shown in FIG. In FIG. 6, similarly to FIG. 3 above, in the sensing scan, the pair of transmission signal lines 21-2 and 21-3 and the pair of reception signal lines 22-2 and 22-3 are selected by the multiplexer 43. It shows the state at a certain time.
At this time, the multiplexer 43 selects, for example, the reception signal line 22-4 adjacent to the reception signal line 22-3 as the correction voltage transmission destination.
In this state, the correction voltage transmission circuit 46 outputs the correction voltage Vc, so that the correction voltage Vc is applied to the reception signal line 22-4. Then, the correction voltage Vc is applied to the received signal line 22-3 via the parasitic capacitance Cr34 between the received signal line 22-3 and the received signal line 22-4. In this case, the received signal value R + can be corrected so that the received signal values R + and R− are well-balanced.

Although not shown, at the scanning timing of the next cell, the pair of received signal lines 22-3 and 22-4 are selected. At that time, the multiplexer 43 is adjacent to, for example, the received signal line 22-4. The reception signal line 22-5 is selected as the correction voltage transmission destination. When the correction voltage transmission circuit 46 outputs the correction voltage Vc in this state, the correction voltage Vc is applied to the reception signal line 22-5, and the parasitic capacitance between the reception signal line 22-4 and the reception signal line 22-5. A correction voltage Vc is applied to the received signal line 22-4, and the received signal value R + can be corrected.

Although the above has been described in the example of correcting the received signal value R +, the received signal value R-side may be corrected. For example, in the scanning state of FIG. 6, the multiplexer 43 selects, for example, the reception signal line 22-1 adjacent to the reception signal line 22-2 as the correction voltage transmission destination, and the correction voltage transmission circuit 46 outputs the correction voltage Vc in that state. do. As a result, the correction voltage Vc is applied to the reception signal line 22-2 via the parasitic capacitance between the reception signal line 22-2 and the reception signal line 22-1, and the reception signal value R- can be corrected.

In this way, either the received signal value R + or R− may be corrected. In some cases, the correction voltage transmission circuit 46 may output two correction voltages to correct both the received signal values R + and R−. These points are the same in each of the examples described below.

Further, the correction voltage transmission destination is not limited to the reception signal line 22 adjacent to the reception signal line 22 selected by scanning, and depending on the correction level, the reception signal line 22 adjacent to two or the reception signal line 22 adjacent to three may be received. The signal line 22 or the like may be selected.
For example, in FIG. 7, when the pair of received signal lines 22-2 and 22-3 are in the selected state as in FIG. 6, the multiplexer 43 sets the received signal line 22-5 as the correction voltage transmission destination as shown by the thick line. Indicates the selected state. Even in this way, the correction voltage can be applied to the received signal lines 22-3 via the parasitic capacitances Cr34 and Cr45.

Further, a plurality of received signal lines 22 may be used as the correction voltage transmission destination. For example, as shown by the broken line in FIG. 7, the received signal lines 22-4 and 22-5 are set as the correction voltage transmission destination.
In this case as well, the correction voltage Vc can be applied to the received signal line 22-3 being scanned.

The amount of correction voltage for the received signal value R + or the received signal value R− can be adjusted depending on which or how many received signal lines 22 are used for the correction voltage transmission destination.

Further, when the reception signal line 22 adjacent to the pair of reception signal lines 22 being scanned is desired to be the correction voltage transmission destination, but the adjacent reception signal line 22 cannot be the correction voltage transmission destination, or the adjacent reception signal line is adjacent. 22 may not exist.
For example, FIG. 8 shows a case where the received signal lines 22-1 and 22-2 are in the selected state by scanning at the time of scanning the cell at the end of the panel. Note that FIG. 8 also shows the capacitances C21, C22, C31, and C32 generated between the transmission signal lines 21-2, 21-3 and the reception signal lines 22-1, 22-2 constituting the cell being scanned.

In this case, there is no adjacent reception signal line 22 even if the correction voltage Vc is to be applied to the reception signal line 22-1.
Therefore, two received signal lines 22 that have not been selected by scanning are used. FIG. 8 shows an example in which received signal lines 22-6 and 22-7 are used, for example.
The multiplexer 43 sets, for example, the received signal line 22-6 to the same receiving channel as the received signal line 22-1 being scanned. As a result, the received signal lines 22-1 and 22-6 are electrically short-circuited.
Next, the reception signal line 22-7 adjacent to the reception signal line 22-6 is set as the correction voltage transmission destination so that the correction voltage Vc from the correction voltage transmission circuit 46 is applied.
In this case, a correction voltage is applied to the reception signal line 22-6 (and the reception signal line 22-1) via the parasitic capacitance Cr67 between the reception signal lines 22-6 and 22-7, and the reception signal value R + is corrected. Will be done.
Of course, in this case as well, the correction voltage transmission destination is not adjacent to the reception signal line 22-6, but may be another reception signal line 22 in the vicinity, or may be a plurality of reception signal lines 22.

By correcting the received signal value (R + or R-) in the non-touch state as in the above example, it is possible to secure a state in which the received signal values R + and R- are balanced in the vicinity of the center value “128” and touch. It is possible to accurately detect the amount of change in the received signal value due to.
As a result, it becomes possible to accurately obtain the change in the signal accompanying the movement of the touched finger, and it is possible to secure the accuracy (accuracy) of the coordinate calculation detection and the coordinate resolution.

By the way, the correction operation as described above needs to be executed according to each cell. This is because the situation in which the signal is balanced or unbalanced differs depending on the cell, and the amount of imbalance also differs.
Therefore, calibration is performed in the adjustment process after the panel of the touch panel device 1, correction operation information suitable for each cell is generated, and a correction table is created.

FIG. 9 shows an example of a correction table.
For example, in the correction table, calibration is performed for each cell (a set of a pair of transmission signal lines 21 and a pair of reception signal lines 22) as items of correction presence / absence, correction voltage, transmission destination line, correction target, and short-circuit line. Appropriate information determined by is stored.

In the figure, each cell shows a combination thereof using the reference numerals of the transmission signal line 21 and the reception signal line 22.
Therefore, the first line of FIG. 9 shows the correction information of the cell by the set of the transmission signal line 21-1,21-2 and the reception signal line 22-1,22-2, and the second line shows the transmission signal line 21-. It is the correction information of the cell by the set of 1,21-2 and the received signal line 22-2, 22-3.

The information on the presence / absence of correction is, for example, a flag indicating the necessity of correction for a cell. Since the correction operation is not necessary for the cell in which the signal is originally balanced when not touched, the information represents the cell that does not require correction.

The information of the correction voltage indicates the correction voltage value output from the correction voltage transmission circuit 46 corresponding to the cell. For example, 1 times, 1/2 times, 1/4 times, etc. can be set with reference to the drive voltage AVCC1 by the transmission circuit 41.

The information on the destination line indicates one or a plurality of received signal lines 22 to be the correction voltage transmission destination. For example, a setting such as whether to use a reception signal line 22 adjacent to the reception signal line 22 being scanned, a reception signal line 22 adjacent to the reception signal line 22 to be scanned, or a plurality of reception signal lines 22 to be used is stored. ..

The information to be corrected is information on whether (or both) the received signal values R + and R− are to be corrected.

The short-circuit line information is information indicating the reception signal line 22 short-circuited to the reception signal line 22 being scanned when the correction voltage is applied as shown in FIG.

For example, such a correction table is set by calibration and stored in the memory 5a of the MCU 5.
The correction table is transferred to the interface register circuit 44 and is used as one of the setting information of the sensing operation.
At the time of scanning, the correction voltage transmission circuit 46 outputs the correction voltage Vc according to the information of the correction voltage for each cell being scanned, and the multiplexer 43 responds to the information of the correction voltage transmission destination and the short-circuit line. Switch the connection status.

FIG. 10 shows the flow of processing of the sensor IC 4 from the start of the sensing scan.
Step S201 shows the selection process of the pair of transmission signal lines 21. The multiplexer 43 selects a pair of transmission signal lines 21 based on a predetermined row selection timing signal.

Step S202 shows the selection process of the pair of received signal lines 22. The multiplexer 43 selects a pair of received signal lines 22 based on a predetermined column selection timing signal.
One cell is selected in the above steps S201 and S202.

In step S203, processing according to the correction table is performed. Specifically, the necessity of correction for the cell selected by scanning is determined based on the information on the presence / absence of correction in the correction table, and if correction is required, the value of the correction voltage Vc for the cell is the correction table. It is confirmed in and set in the correction voltage transmission circuit 46.
Further, the multiplexer 43 sets the connection of the correction voltage transmission destination based on the information of the transmission destination line in the correction table. Further, the connection setting based on the short circuit line information may be performed in the multiplexer 43.
As described above, the cell to be corrected is set to the state where the correction voltage is applied at the time of sensing.

In step S204, the sensing process by the transmitting circuit 41 and the receiving circuit 42 is performed. This is the process described with reference to FIG.
Here, when correction is performed, the correction voltage is applied in step S102 of FIG. That is, the correction voltage transmission circuit 46 outputs the correction voltage Vc.
Therefore, in the active period, the received signal values R + and R− in step S103 are compared with the correction voltage Vc applied.

After that, when the process returns to step S101 via steps S107 and S108, that is, when the idle period is entered, the output of the correction voltage by the correction voltage transmission circuit 46 is stopped.
The correction voltage Vc may be continuously output until the corresponding cell is scanning, that is, from step S107 to S109 in FIG.
However, during the idle period, the received signal values R + and R- become ground levels as described above, and there is no effect due to the application of the correction voltage Vc. Therefore, as described above, power consumption can be reduced by stopping during the idle period. It is conceivable to do.

When the sensing for one cell is completed in step S204 of FIG. 10 as shown in FIG. 5, the process proceeds to step S205 of FIG.
If the cell this time is not the final set of column scans, that is, the set of received signal lines 22- (m-1) and 22-m, the process returns to step S202 and proceeds to sensing of the next set. For example, if the cell this time is a set of received signal lines 22-1, 22-2, the set of received signal lines 22-2, 22-3 is selected as the next cell in step S202 (in this case, the transmission signal). Line 21 is the same two as the previous cell).

If the cell this time is the final set of column scans (set of received signal lines 22- (m-1), 22-m), the process proceeds to step S206, it is determined whether or not the scan is completed, and the process is continued. If, the process returns to step S201 and proceeds to the next set of sensing.
For example, if the cell this time is a set of transmission signal lines 21-1, 21-2, the transmission signal lines 21-2, 21-3 and the reception signal lines 22-1, 22-2 are used as the next cells in step S201. Select a pair of.

The above processing is repeated until the sensing ends (for example, the power of the touch panel device 1 is turned off).
Therefore, based on the correction table, the correction voltage value and the connection setting of the correction voltage transmission destination are set so that the necessary correction is performed only for the cells that need to be corrected. That is, the correction for the balance of the received signal values R + and R− adapted to each cell is executed.

<4. Summary and modification>
According to the touch panel device 1 or the touch panel drive device 3 of the above embodiment, the following effects can be obtained.

The touch panel drive device 3 of the embodiment is a touch panel drive device that sequentially scans the touch panel 2 to select a pair of adjacent transmission signal lines 21 and a pair of adjacent reception signal lines 22. Then, the receiving circuit 42 receives and compares the received signals R + and R- whose waveform changes due to the capacitance change accompanying the operation from the pair of received signal lines 22 of the touch panel 2, and the detection value of the touch panel operation ( RAW value) is generated.
Further, the touch panel drive device 3 includes a correction voltage transmission circuit 46, and the correction voltage transmission circuit 46 corresponds to a pair of reception signal lines 22 that are selected in the scanning process, and receives signals other than the pair of reception signal lines 22. The correction voltage Vc to be transmitted to the signal line 22 is output.
That is, a pair of received signal lines 22 are sequentially selected in the scanning process, but when a certain pair of received signal lines 22 is selected, a predetermined correction voltage is applied to the received signal lines 22 in a non-selected state for scanning. Is applied. As a result, the correction voltage can be applied to the received signal line 22 in the selected state via the parasitic capacitance, and the levels of the received signals R + and R- by the pair of received signal lines 22 in the selected state are balanced. Can be. As a result, the receiving circuit 42 can correctly compare the received signals R + and R− to generate a detected value.
Therefore, it is possible to provide the touch panel device 1 having high accuracy in terms of coordinate detection accuracy and resolution.
Moreover, it is not necessary to change the configuration of the receiving circuit 42 or the detection processing method.
Even if the balance of the received signal values R + and R- is biased, the correction can be performed by using the function of the sensor IC4 without changing the hardware design on the touch panel 2 side such as the sensor pattern and wiring. can.

In the embodiment, in the process of scanning, a pair of received signal lines 22 are sequentially selected by the multiplexer 43 and connected to the receiving circuit 42, but the received signal lines other than the pair of received signal lines to be selected are connected to the receiving circuit 42. One of them is selected as the correction voltage transmission destination by the multiplexer 43 and is connected to the correction voltage transmission circuit 46.
The multiplexer 43 has a configuration in which transmission / reception can be arbitrarily set across all transmission signal lines 21 and reception signal lines 22 in the sensor IC 4, whereby scanning of the transmission signal line 21 and the reception signal line 22 can be performed. Make a choice for. By using this multiplexer 43 to select the reception signal line 22 to which the correction voltage is applied, the correction is performed without changing or complicating the wiring of the reception signal lines 22-1 to 22-n. It is possible to apply a voltage.

In the embodiment, as the reception signal line 22 to which the correction voltage is transmitted, the reception signal line 22 adjacent to the reception signal line 22 selected by scanning can be selected (see FIG. 6).
As a result, the correction voltage can be efficiently applied via the parasitic capacitance between the adjacent signal lines.
Further, in the embodiment, as shown in FIG. 7, an example in which a correction voltage is applied using a received signal line 22 that is not adjacent to the pair of received signal lines 22 in the selected state by scanning is also given.
By properly using the case where the correction voltage is applied to the adjacent reception signal lines 22 as shown in FIG. 6 and the case where the correction voltage is applied to the non-adjacent received signal lines 22 as shown in FIG. 7, a cell (a pair of transmission signals) is used. The correction effect can be adjusted for each set of the line 21 and the pair of received signal lines 22). That is, it is possible to realize the correction corresponding to the difference in the imbalance degree of the pair of received signal lines 22 depending on the cell.
It is also possible to apply a correction voltage to a plurality of reception signal lines 22, and the correction effect can be adjusted by the number of reception signal lines to which the correction voltage is applied.
By using the multiplexer 43, it is possible to easily realize the selection and setting of the number of the received signal lines 22 for transmitting these correction voltages Vc for each cell.
As a result, the correction effect can be adjusted by selecting the signal line to which the correction voltage is applied, so that the types of correction voltage values generated by the correction voltage transmission circuit 46 can be reduced, and the circuit configuration can be simplified.
The voltage value of the correction voltage Vc is set to 1 times, 1/2 times, 1/4 times, etc. with respect to the drive voltage AVCC1, but of course, it may be changed in more stages.
Alternatively, the voltage value of the correction voltage Vc may be fixed, and the correction level may be adjusted by selecting the reception signal line 22 for transmitting the correction voltage Vc and setting the number as described above. In particular, as shown in FIG. 7, when the correction voltage Vc is applied by selectively using the reception signal lines 22 that are not adjacent to the pair of reception signal lines 22 in the selected state by scanning, the correction voltage Vc itself is driven. Even if the voltage is 1 times, 1/2 times, 1/4 times, etc. with respect to the voltage AVCC1, the amount of correction voltage actually applied can be adjusted more finely.

In the embodiment, one received signal line 22 other than the pair of received signal lines 22 selected by scanning is short-circuited to any one of the pair of received signal lines 22 in the selected state, and becomes one received signal line 22. Is capable of transmitting the correction voltage Vc to yet another reception signal line 22 (see FIG. 8).
As a result, the correction voltage can be applied using the reception signal lines 22 that are separated from the pair of reception signal lines 22 in the selected state by scanning. For example, even when the reception signal lines 22 adjacent to the pair of reception signal lines 22 cannot be selected (or do not exist) as the correction voltage transmission destination, the correction can be performed.

In the embodiment, at least the correction voltage and the reception signal line (transmission destination line) of the correction voltage transmission destination are stored for each pair of the pair of transmission signal lines 21 and the pair of reception signal lines 22 selected by scanning. The correction voltage is transmitted according to the correction table.
As a result, an appropriate correction is realized according to the imbalance status for each cell (a pair of transmission signal lines 21 and a pair of reception signal lines 22), the necessity of correction, the wiring position, and the like.
Specifically, the correction voltage transmission circuit 46 outputs the voltage value specified in the correction table at the timing of each cell, and the multiplexer 43 outputs the reception signal line 22 of the transmission destination specified in the correction table at the timing of each cell. It is sufficient to select, and the correction operation according to each cell can be realized by the processing with less load.

Although the touch panel device 1 of the embodiment has been described as performing a touch operation that actually touches the panel surface, the present invention is a touch panel corresponding to so-called hover sensing (non-contact proximity operation) that performs an operation equivalent to a touch. The device is also included, and in that case, the correction operation can be applied in the same manner as described above. That is, the "touch" in the present invention and the embodiment also includes a non-contact proximity operation state.

Further, the configuration and operation of the embodiment are examples. In the present invention, various configuration examples and operation examples can be considered.
The receiving circuit 42 and the measuring capacitance unit 424 are not limited to the configuration shown in FIG.
Although the reception circuit 42 and the correction voltage transmission circuit 46 are connected to the reception signal line 22 via a common multiplexer 43, the connection state to the reception signal line 22 may be switched by independent switching circuits. ..

1 Touch panel device, 2 Touch panel, 3 Touch panel drive device, 4 Sensor IC, 5 MCU, 5a memory, 21,21-1 to 21-m transmission signal line, 22,22-1 to 22-n reception signal line, 41 transmission Circuit, 42 receiver circuit, 43 multiplexer, 44 interface register circuit, 45 power supply circuit, 46 correction voltage transmission circuit, 411,412 driver, 421 comparator, 422 reference capacitance section, 423,425 switch, 424 measurement capacitance section, 426 Calculation control unit

Claims (7)

A touch panel drive device that sequentially scans a touch panel to select a pair of adjacent transmission signal lines and a pair of adjacent reception signal lines.
A receiving circuit that generates a detected value for touch panel operation by receiving and comparing each received signal whose waveform changes due to a change in capacitance due to operation from the pair of received signal lines on the touch panel.
A touch panel drive device including a correction voltage transmission circuit that outputs a correction voltage to be transmitted to a reception signal line other than the pair of reception signal lines corresponding to the pair of reception signal lines selected by the scanning. In the process of scanning, a pair of received signal lines are sequentially selected by the multiplexer and connected to the receiving circuit, and received signal lines other than the pair of received signal lines to be selected are selected by the multiplexer. The touch panel drive device according to claim 1, which is connected to the correction voltage transmission circuit. The touch panel drive device according to claim 1 or 2, wherein a received signal line adjacent to the received signal line selected in the scanning can be selected as the received signal line to which the correction voltage is transmitted. The touch panel drive device according to claim 1 or 2, wherein a received signal line not adjacent to the received signal line selected in the scanning can be selected as the received signal line to which the correction voltage is transmitted. One of the received signal lines other than the pair of received signal lines selected in the scanning is short-circuited to one of the pair of received signal lines, and the received signal line is corrected to a different received signal line from the one received signal line. The touch panel drive device according to any one of claims 1 to 4, wherein a voltage can be transmitted. A claim that a correction voltage is transmitted for each pair of a pair of transmission signal lines and a pair of reception signal lines selected in the scan according to a correction table in which at least the correction voltage and the reception signal line of the correction voltage transmission destination are stored. The touch panel drive device according to any one of items 1 to 5. Touch panel and
The touch panel has a touch panel driving device that sequentially performs scanning for selecting a pair of adjacent transmission signal lines and a pair of adjacent reception signal lines.
The touch panel drive device is
A receiving circuit that generates a detected value for touch panel operation by receiving and comparing each received signal whose waveform changes due to a change in capacitance due to operation from the pair of received signal lines on the touch panel.
A correction voltage transmission circuit that outputs a correction voltage to be transmitted to a reception signal line other than the pair of reception signal lines corresponding to the pair of reception signal lines selected in the scanning.
Touch panel device equipped with.

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