Patent Publication Number: US-11650702-B2

Title: Sensing device including a first electrode receiving a first driving signal and a second electrode receiving a second driving signal

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 16/813,943 filed Mar. 10, 2020, which claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2019-0066785, filed on Jun. 5, 2019 in the Korean Intellectual Property Office, the disclosures of which are incorporated by reference herein in their entirety. 
    
    
     TECHNICAL FIELD 
     Exemplary embodiments of the present inventive concept relate to a touch panel controller and a sensing device including the same. 
     DISCUSSION OF RELATED ART 
     As display devices have been miniaturized, interference between a touch panel and a display panel included in display devices has increased. Accordingly, magnitudes of noise signals generated in display devices have also increased. 
     In a display device, noise signals flowing into a touch panel from a display panel may degrade sensing sensitivity, and noise signals flowing into the display panel from the touch panel may degrade image quality. 
     SUMMARY 
     According to an exemplary embodiment of the present inventive concept, a sensing device includes a touch panel including a plurality of first sensor electrodes and a plurality of second sensor electrodes, and a touch panel controller acquiring a sensing signal from the touch panel and detecting a user input based on the sensing signal. The touch panel controller acquires the sensing signal from at least one of the plurality of first sensor electrodes and the plurality of second sensor electrodes in a first mode operating at a first power. The touch panel controller selects a first transmitting electrode, a second transmitting electrode, and a plurality of receiving electrodes from one of the plurality of first sensor electrodes and the plurality of second sensor electrodes, inputs a first driving signal to the first transmitting electrode, and inputs a second driving signal to the second transmitting electrode in a second mode operating at a second power lower than the first power, and a third mode in which a proximity sensing operation is performed. The second power has a phase difference of 180 degrees with respect to the first driving signal. 
     According to an exemplary embodiment of the present inventive concept, a sensing device includes a first electrode receiving a first driving signal and a second electrode receiving a second driving signal, a plurality of third electrodes disposed between the first electrode and the second electrode and extending in a direction that is the same as directions of the first electrode and the second electrode, an electric charge amplifier outputting a first voltage signal corresponding to a change in capacitance between a portion of the plurality of third electrodes and the first electrode, and outputs a second voltage signal corresponding to a change in capacitance between the other portion of the plurality of third electrodes and the second electrode, and a processor detecting a user input using the first voltage signal and the second voltage signal. The first driving signal and the second driving signal have a phase difference of 180 degrees therebetween. 
     According to an exemplary embodiment of the present inventive concept, a touch panel controller includes a sensing circuit driving a touch panel including a plurality of first sensor electrodes and a plurality of second sensor electrodes, selecting a plurality of first receiving electrodes, a plurality of second receiving electrodes, and at least one shielding electrode from one of the plurality of first sensor electrodes and the plurality of second sensor electrodes, and acquiring a sensing signal from among the plurality of first receiving electrodes and the plurality of second receiving electrodes, and a processor controlling the sensing circuit and detecting a user input using the sensing signal. The shielding electrode is disposed between the plurality of first receiving electrodes and the plurality of second receiving electrodes. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and other aspects and features of the present inventive concept will be more clearly understood by describing in detail exemplary embodiments thereof with reference to the accompanying drawings. 
         FIG.  1    is a diagram illustrating a sensing device including a touch panel controller according to an exemplary embodiment of the present inventive concept. 
         FIG.  2    is a diagram illustrating an operational mode of a sensing device according to an exemplary embodiment of the present inventive concept. 
         FIG.  3    is a block diagram illustrating configuration of the touch panel controller of  FIG.  1    according to an exemplary embodiment of the present inventive concept; 
         FIG.  4    is a circuit diagram illustrating the touch panel controller of  FIG.  1    according to an exemplary embodiment of the present inventive concept. 
         FIGS.  5  and  6    are diagrams illustrating a method for driving a touch panel with a touch panel controller according to exemplary embodiments of the present inventive concept. 
         FIG.  7    is a diagram illustrating a method of removing a noise signal by a touch panel controller according to an exemplary embodiment of the present inventive concept. 
         FIGS.  8 A to  8 C  are diagrams illustrating an effect of reducing the number of driving channels of a touch panel controller according to exemplary embodiments of the present inventive concept. 
         FIGS.  9  and  10    are diagrams illustrating a method of driving a touch panel with a touch panel controller according to exemplary embodiments of the present inventive concept. 
         FIGS.  11  to  13    are diagrams illustrating a method of driving a touch panel with a touch panel controller according to exemplary embodiments of the present inventive concept. 
         FIG.  14    is a block diagram illustrating an electronic device including a sensing device according to an exemplary embodiment of the present inventive concept. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Exemplary embodiments of the present inventive concept provide a touch panel controller which may remove noise signals between a touch panel and a display panel and may significantly reduce power consumption, and a sensing device including the same. 
     Hereinafter, exemplary embodiments of the present inventive concept will be described in detail with reference to the accompanying drawings. Like reference numerals may refer to like elements throughout this application. 
       FIG.  1    is a diagram illustrating a sensing device including a touch panel controller according to an exemplary embodiment. 
     Referring to  FIG.  1   , a display device may include a touch panel  100 , a touch panel controller  200 , and a display panel  300 . The touch panel  100  and the touch panel controller  200  may be included in a sensing device. 
     The touch panel  100  may be disposed on an upper portion of the display panel  300  and may overlap the display panel  300 . For example, the touch panel  100  may be disposed in an upper portion of an image display surface of the display panel  300 .  FIG.  1    illustrates an example in which the touch panel  100  is spaced apart from the display panel  300 , but the inventive concept is not limited thereto. For example, the touch panel  100  may be integrated with the display panel  300 . 
     The touch panel  100  may include at least one or more transparent substrates and a plurality of sensor electrodes  110  and  120  disposed on the at least one or more transparent substrates. The plurality of sensor electrodes  110  and  120  may be formed of a transparent conductive material such as indium tin oxide (ITO), zinc oxide (ZnO), indium zinc oxide (IZO), a carbon nanotube, or the like, or may include an extremely thin metal pattern. 
     The plurality of sensor electrodes  110  and  120  may include a plurality of first sensor electrodes  110  extending in a first direction DIR 1  and a plurality of second sensor electrodes  120  extending in a second direction DIR 2  perpendicular to the first direction DIR 1 , disposed on the at least one or more transparent substrates. 
     In  FIG.  1   , the first sensor electrodes  110  and the second sensor electrodes  120  may have a matrix shape, but the shape is not limited thereto. For example, the first sensor electrodes  110  and the second sensor electrodes  120  may have various other shapes, such as a diamond shape, a circular shape, or the like. 
     The first sensor electrodes  110  may be electrically isolated from the second sensor electrodes  120 . For example, the first sensor electrodes  110  may be electrically isolated from the second sensor electrodes  120  by being spaced apart from the second sensor electrodes  120  in a third direction DIR 3  perpendicular to the first and second directions DIR 1  and DIR 2 . In this case, a space between the first sensor electrodes  110  and the second sensor electrodes  120  may be insulated using an insulating material such as silicon oxide or the like. 
     The touch panel controller  200  may be electrically connected to the touch panel  100  and may transmit and receive various signals required for detecting a user input. For example, when the sensing device operates based on a mutual-capacitance method, the touch panel controller  200  may transmit a driving signal to at least one of the first sensor electrodes  110  and the second sensor electrodes  120  of the touch panel  100 , and may receive a sensing signal from at least one of the first sensor electrodes  110  and the second sensor electrodes  120 . Additionally, when the sensing device operates based on a self-capacitance method, the touch panel controller  200  may receive a sensing signal from at least one of the first sensor electrodes  110  and the second sensor electrodes  120 . In exemplary embodiments of the present inventive concept, the sensor electrodes receiving a driving signal may be referred to as transmitting electrodes TXE, and the sensor electrodes outputting a sensing signal may be referred to as receiving electrodes RXE. 
     The touch panel controller  200  may include an analog circuit, an analog-digital converter, a processor, or the like, for transmitting and receiving various signals for detecting a user input. 
     The display panel  300  may include a plurality of scan lines and a plurality of data lines. The display panel  300  may also include a plurality of pixels connected to the scan lines and the data lines. The display panel  300  may receive various driving signals via the scan lines and the data lines and may drive the plurality of pixels, to display various images. The display panel  300  may include a liquid crystal display (LCD), a light emitting diode (LED) display, an organic light emitting diode (OLED) display, or the like. 
       FIG.  2    is a diagram illustrating an operational mode of a sensing device according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG.  2   , an operational mode of a sending device may include first to third modes of which operational timings are different from one another depending on a level of driving power, a method of driving a sensor line (referred to interchangeably as “a sensor electrode”), or the like. 
     In the first mode, the sensing device may be supplied with first power P 1  that is the same as or higher than a predetermined threshold value Pth, and may perform a sensing operation. In exemplary embodiments of the present inventive concept, the sensing device may perform the sensing operation based on a self-capacitance method. In this case, the sensing device may select a plurality of transmitting electrodes and a plurality of receiving electrodes from first sensor electrodes and second sensor electrodes. 
     In the first mode, a single frame period of the sensing device may include an active section act 1  and an inactive section inact 1 . In the active section act 1 , the sensing device may detect whether a user input occurs and a position (a coordinate value) in which the user input occurs. In the inactive section inact 1 , the sensing device may not perform a sensing operation to reduce power consumption. In exemplary embodiments of the present inventive concept, a time period t act1  of the active section act 1  may be longer than a time period t inact1  of the inactive section inact 1 . 
     In the second mode, the sensing device may be supplied with second power P 2  that is less than the predetermined threshold value Pth, and may perform a sensing operation. In exemplary embodiments of the present inventive concept, the sensing device may perform a sensing operation based on a self-capacitance method. In this case, the sensing device may select a plurality of transmitting electrodes and a plurality of receiving electrodes from one of the first sensor electrodes and the second sensor electrodes. 
     In the second mode, a single frame period of the sensing device may include an active section act 2  and an inactive section inact 2 . In the active section act 2 , the sensing device may only detect whether a user input occurs. In the inactive section inact 2 , the sensing device may not perform a sensing operation to reduce power consumption. In exemplary embodiments of the present inventive concept, a time period t act2  of the active section act 2  may be shorter than a time period t inact2  of the inactive section inact 2 . 
     In the third mode, the sensing device may perform a sensing operation based on a self-capacitance method without a limitation in driving power. For example, the sensing device may be supplied with power that is the same as or higher than the first power P 1 , and may perform a proximity sensing operation to acquire a hovering signal in which a signal-to-noise ratio (SNR) is at a maximum. In this case, the sensing device may select a plurality of transmitting electrodes and a plurality of receiving electrodes from one of the first sensor electrodes and the second sensor electrodes. 
     In the third mode, a single frame period of the sensing device may only include an active section act 3 . During the active section act 3 , the sensing device may perform a proximity sensing operation. In the proximity sensing operation, a change in capacitance of the sensing device may be relatively small as compared to a touch sensing operation, and accordingly, it may be necessary to increase sensing sensitivity. Thus, in the third mode, the sensing device may lengthen a time period t act3  of the active section act 3  in which a sensing operation is performed to be longer than the time periods t act1  and t act2  of the other modes, or may increase a magnitude of a driving signal. 
       FIG.  3    is a block diagram illustrating a configuration of the touch panel controller of  FIG.  1    according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG.  3   , a touch panel controller  200  may include a sensing circuit  210  and a processor  230 . 
     The sensing circuit  210  may be electrically connected to the touch panel  100  and may receive various signals required for detecting a user input. For example, when the sensing device operates based on a mutual-capacitance method, the sensing circuit  210  may transmit a driving signal to a transmitting electrode TXE, and may receive a sensing signal from a receiving electrode RXE. When the sensing device operates based on a self-capacitance method, the sensing circuit  210  may receive a sensing signal from the receiving electrode RXE. In exemplary embodiments of the present inventive concept, a driving signal may be a square wave signal, and the sensing signal may be an electrical signal corresponding to electric charge generated by the sensor electrodes. 
     The sensing circuit  210  may include a driver selecting a transmitting electrode TXE and a receiving electrode RXE and transmitting a driving signal to the transmitting electrode TXE, an electric charge amplifier converting electric charge generated in the receiving electrode RXE to a voltage signal and outputting the voltage signal, an analog-digital converter converting the voltage signal output from the electric charge amplifier to a digital signal, and the like. 
     The processor  230  may control overall operations of the touch panel controller  200 , may receive a digital signal from the sensing circuit  210 , and may detect whether a user input occurs, a position in which a user input occurs (a coordinate value), or the like. The processor  230  may be implemented as a digital signal processor (DSP) or the like. 
       FIG.  4    is a circuit diagram illustrating the touch panel controller of  FIG.  1    according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG.  4   , the touch panel controller  200  may include the sensing circuit  210  and the processor  230 . 
     The sensing circuit  210  may include a driver  211 , an electric charge amplifier  213 , an analog-digital converter  215 , and a timing controller  217 . 
     The driver  211  may select at least one transmitting electrode TXE and at least one receiving electrode RXE from among first sensor electrodes and second sensor electrodes. In exemplary embodiments of the present inventive concept, the driver  211  may include a multiplexer MUX for selecting a transmitting electrode TXE and a receiving electrode RXE. 
     The driver  211  may input a driving signal to the transmitting electrode TXE through a transmitter T X , and may receive a sensing signal from the receiving electrode RXE through a receiver R X . In exemplary embodiments of the present inventive concept, a driving signal may be a square wave voltage signal having a peak-to-peak V TX  of a certain level. 
     The electric charge amplifier  213  may include an operational amplifier AMP, a feedback resistor R FB , and a feedback capacitor C FB . The feedback resistor R FB  may be connected between an inverting input terminal and an output terminal of the operational amplifier AMP, and the feedback capacitor C FB  may be connected to the feedback resistor R FB  in parallel. A reference voltage V REF  having a certain level may be input to a non-inverting input terminal of the operational amplifier AMP. In exemplary embodiments of the present inventive concept, the reference voltage V REF  may be a display noise signal VDN generated between the receiving electrode RXE and a common electrode of a display panel. The electric charge amplifier  213  may perform an amplifying operation using the display noise signal VDN as the reference voltage V REF , thus removing the display noise signal VDN. The feedback resistor R FB  and the feedback capacitor C FB  may perform a filtering function to remove a ripple element from a voltage signal output from the electric charge amplifier  213 . 
     The analog-digital converter  215  may convert a voltage signal output from the electric charge amplifier  213  to a digital signal, and may output the digital signal. 
     In exemplary embodiments of the present inventive concept, the sensing circuit  210  may further include a gain amplifier, such as a programmable gain amplifier (PGA), or an integrator, connected between an output terminal of the electric charge amplifier  213  and an input terminal of the analog-digital converter  215 , to secure a maximum dynamic range. 
     The sensing circuit  210  may further include an offset compensator  219  connected to the inverting input terminal of the electric charge amplifier  213  to remove an offset of electric charge generated by the receiving electrode RXE to secure a maximum dynamic range. 
     The driver  211 , the offset compensator  219 , and the other elements described above may operate in accordance with timing signals TCON 1  to TCON 4  generated by the timing controller  217  under control of the processor  230 . 
     The digital noise signal VDN, or a first noise signal VDN, flowing into the touch panel  100  from the display panel may be generated due to a first parasitic capacitance C S  element generated between the receiving electrode RXE of the touch panel  100  and a common electrode of the display panel. The first noise signal VDN may decrease a magnitude of a sensing signal output from the receiving electrode RXE and may degrade sensing sensitivity. 
     A second noise signal VTN flowing into the display panel from the touch panel  100  may be generated due to a second parasitic capacitance C D  element generated between the transmitting electrode TXE of the touch panel  100  and a common electrode of the display panel. The second noise signal VTN may degrade quality of an image of the display panel. 
     A mutual capacitance C M  formed between the receiving electrode RXE and the transmitting electrode TXE will be described in detail below. 
     A magnitude of each of the first noise signal VDN and the second noise signal VTN may increase as a gap between the touch panel  100  and the display panel decreases. Thus, the touch panel controller  200  may drive the touch panel  100  differently depending on an operational mode of the sensing device to remove the first noise signal VDN and the second noise signal VTN and to significantly reduce power consumption. 
     In the description below, a method of driving a touch panel by a touch panel controller in accordance with an operational mode will be described in more detail with reference to  FIGS.  5  to  7   . 
       FIGS.  5  and  6    are diagrams illustrating a method for driving a touch panel with a touch panel controller according to exemplary embodiments of the present inventive concept.  FIG.  7    is a diagram illustrating a method of removing a noise signal by a touch panel controller according to an exemplary embodiment of the present inventive concept. 
       FIG.  5    illustrates a method of driving a touch panel  500  when a sensing device operates in the first mode, and  FIG.  6    illustrates a method of driving a touch panel  600  when a sensing device operates in the second mode and the third mode. In the exemplary embodiments of  FIGS.  5  and  6   , the sensing device may perform a sensing operation based on a mutual-capacitance method. 
     Referring to  FIG.  5   , when the sensing device operates in the first mode, the touch panel controller  200  may select first sensor electrodes  510  as transmitting electrodes TXE, and may select second sensor electrodes  520  as receiving electrodes RXE. 
     The touch panel controller  200  may input a driving signal to the transmitting electrodes TXE through a transmitter TX. Additionally, the touch panel controller  200  may receive a sensing signal from the receiving electrodes RXE through a receiver RX and may detect whether a user input occurs and a position (a coordinate value) in which the user input occurs. 
       FIG.  5    illustrates an example in which the first sensor electrodes  510  are the transmitting electrodes TXE and the second sensor electrodes  520  are the receiving electrodes RXE, but the inventive concept is not limited thereto. For example, the touch panel controller  200  may select the first sensor electrodes  510  as the receiving electrodes RXE and may select the second sensor electrodes  520  as the transmitting electrodes TXE. 
     Referring to  FIG.  6   , when the sensing device operates in the second mode or the third mode, the touch panel controller  200  may select at least a pair of transmitting electrodes TXE+ and TXE− from one of first sensor electrodes  610  and second sensor electrodes  620 . Each pair of the transmitting electrodes TXE+ and TXE− may include a first transmitting electrode TXE+connected to a transmitter TX+ and a second transmitting electrode TXE− connected to a transmitter TX−. A plurality of sensor electrodes may be disposed between the first transmitting electrode TXE+ and the second transmitting electrode TXE−. 
     The touch panel controller  200  may select a plurality of receiving electrodes RXE+ and RXE− from among a plurality of sensor electrodes disposed between the first transmitting electrode TXE+ and the second transmitting electrode TXE−. The plurality of receiving electrodes RXE+ and RXE− may include a first receiving electrode RXE+ connected to a receiver RX+ and a second receiving electrode RXE− connected to a receiver RX−. The first receiving electrode RXE+ may form a mutual capacitance C M  with an adjacent first transmitting electrode TXE+, and the second receiving electrode RXE− may form the mutual capacitance C M  with an adjacent second transmitting electrode TXE−. 
     In exemplary embodiments of the present inventive concept, the touch panel controller  200  may select at least one shielding electrode disposed between the first transmitting electrode TXE+ and the second transmitting electrode TXE− to prevent the mutual capacitance C M  from being formed between the first transmitting electrode TXE+ and the second receiving electrode RXE− and between the second transmitting electrode TXE− and the first receiving electrode RXE+. In an exemplary embodiment of the present inventive concept, the touch panel controller  200  may select at least one of the plurality of sensor electrodes disposed between the first transmitting electrode TXE+ and the second transmitting electrode TXE− adjacent to the first transmitting electrode TXE+, and may connect the selected sensor electrode to a ground power or may float the selected sensor electrode, thus forming the shielding electrode. 
     The touch panel controller  200  may input a first driving signal IN 1  to the first transmitting electrode TXE+ through the transmitter TX+. The touch panel controller  200  may also input a second driving signal IN 2 , having a phase difference of 180 degrees with respect to the first driving signal IN 1 , to the second transmitting electrode TXE− through the transmitter TX−. 
     The touch panel controller  200  may remove the second noise signal VTN flowing into the display panel from the touch panel  600  due to the second parasitic capacitance C D  element by inputting the first driving signal IN 1  and the second driving signal IN 2  having a phase difference of 180 degrees therebetween to each pair of the transmitting electrodes TXE+ and TXE−. The touch panel controller  200  may also remove the first noise signal VDN flowing into the touch panel  600  from the display panel due to the first parasitic capacitance C S  element by inputting the first driving signal IN 1  and the second driving signal IN 2  having a phase difference of  180  degrees therebetween to each pair of the receiving electrodes RXE+ and RXE−. 
     The touch panel controller  200  may connect one of the first sensor electrodes  610  and the second sensor electrodes  620 , from which none of the transmitting electrodes TXE or the receiving electrodes RXE are selected, to a ground power or may float the sensor electrode, thus significantly reducing an effect of non-driven sensor electrodes affecting the transmitting electrodes TXE and the receiving electrodes RXE. 
       FIG.  6    illustrates an example in which the transmitting electrodes TXE and the receiving electrodes RXE are selected from among the second sensor electrodes  620 , but the inventive concept is not limited thereto. The touch panel controller  200  may select the transmitting electrodes TXE and the receiving electrodes RXE from among the first sensor electrodes  610 . 
     In the description below, an example of removing the first noise signal VDN and the second noise signal VTN by the touch panel controller  200  will be described in greater detail with reference to  FIG.  7   . 
     In  FIG.  7   , only five first sensor electrodes  711  to  715  included in a touch panel  700  are illustrated for ease of description. 
     Referring to  FIG.  7   , the touch panel controller  200  may select a 1st first sensor electrode  711  as a first transmitting electrode TXE+, and may select a 5th first sensor electrode  715  as a second transmitting electrode TXE−. Additionally, the touch panel controller  200  may select a 2nd first sensor electrode  712  as a first receiving electrode RXE+, and may select a 4th first sensor electrode  714  as a second receiving electrode RXE−. The touch panel controller  200  may float a 3rd first sensor electrode  713  and may select the 3rd first sensor electrode  713  as a shielding electrode. 
     The touch panel controller  200  may input the first driving signal IN 1  to the first transmitting electrode TXE+, and may input the second driving signal IN 2  having a magnitude the same as a magnitude of the first driving signal IN 1  and having a phase different from a phase of the first driving signal INT 1  by 180 degrees. In this case, the mutual capacitance CM may be formed between the first transmitting electrode TXE+ and the first receiving electrode RXE+, and a current path may be formed through the mutual capacitance CM. The mutual capacitance CM may also be formed between the second transmitting electrode TXE− and the second receiving electrode RXE−, and a current path may be formed through the mutual capacitance CM. 
     The first sensor electrodes  711  to  715  may have substantially the same area and substantially the same length. Accordingly, when an error in process is not considered, first parasitic capacitances C S  formed in each of the receiving electrodes RXE+ and RXE− may be substantially the same, and second parasitic capacitances C D  formed in each of the transmitting electrodes TXE+ and TXE− may be substantially the same. 
     Noise flowing into a common electrode of the display panel from the first transmitting electrode TXE+ may be C D ×V TX , and noise flowing into a common electrode of the display panel from the second transmitting electrode TXE− may be −C D ×V TX . Thus, the noises may be offset by each other and may be removed. 
     A first sensing signal OUT 1  output from the first receiving electrode RXE+ may be represented by Equation 1 below.
 
OUT1=Δ C   M   V   TX   +C   S   V   DN   [Equation 1]
 
     In Equation 1, “V DN ” may refer to display noise generated between the receiving electrode RXE+ and the common electrode of the display panel. 
     A second sensing signal OUT 2  output from the second receiving electrode RXE− may be represented by Equation 2 below.
 
OUT2=−Δ C   M   V   TX   +C   S   V   DN   [Equation 2]
 
     In Equation 2, “V DN ” may refer to display noise generated between the receiving electrode RXE− and the common electrode of the display panel. 
     The touch panel controller  200  may differentiate the second sensing signal OUT 2  from the first sensing signal OUT 1 , thus generating a final sensing signal OUT used for detecting a user input. Accordingly, the final sensing signal OUT may be represented by Equation 3 below.
 
OUT=OUT1−OUT2=(Δ C   M   V   TX   +C   S   V   DN )−(−Δ C   M   V   TX   +C   S   V   DN )=2Δ C   M   V   TM   [Equation 3]
 
     Referring to Equation 3, the display noises V DN  may be offset by each other and may be removed. Additionally, a magnitude of the final sensing signal OUT may increase by twice the magnitudes of the first and second sensing signals OUT 1  and OUT 2 . 
     Consequently, the touch panel controller  200  in the present exemplary embodiment may configure the transmitting electrodes TXE+ and TXE− as a pair of transmitting electrodes in which signals having a phase difference of 180 degrees therebetween are input, respectively, may select the receiving electrodes RXE+ and RXE− to be disposed in parallel to the transmitting electrodes TXE+ and TXE−, and may perform a differential calculation with respect to the first and second sensing signals OUT 1  and OUT 2  output from the receiving electrodes RXE+ and RXE−, respectively As such, all noise elements caused by mutual interference between the touch panel  600  and the display panel may be removed. Thus, without considering noise elements, the touch panel controller  200  may increase a magnitude V TX  of the driving signals IN 1  and IN 2 , and accordingly, sensing sensitivity and image quality of the display panel may improve. 
     Additionally, the touch panel controller  200  in the present exemplary embodiment may increase a magnitude of the final sensing signal OUT to twice the magnitude of each of the first and second sensing signals OUT 1  and OUT 2 . Accordingly, the touch panel controller  200  may decrease the number of sensor lines required for detecting a user input in the same size of a sensing area, thus reducing power consumption. 
       FIGS.  8 A to  8 C  are diagrams illustrating an effect of reducing the number of driving channels of a touch panel controller according to exemplary embodiments of the present inventive concept. 
     In the exemplary embodiments illustrated in  FIGS.  8 A to  8 C , the sensing areas SA may have substantially the same area. 
     Referring to  FIG.  8 A , when a sensing device operates in the first mode, five transmitting lines TXE (selected from second sensor electrodes  820 ) respectively connected to transmitters TX and three receiving lines RXE (selected from first sensor electrodes  810 ) respectively connected to receivers RX may perform a sensing operation based on a mutual-capacitance method, in the sensing area SA. 
     Referring to  FIG.  8 B , when the sensing device operates in the first mode, five receiving lines RXE respectively connected to receivers RX may perform a sensing operation based on a self-capacitance method, in the sensing area SA. 
     Referring to  FIG.  8 C , different from the aforementioned exemplary embodiments, when the sensing device operates in the second mode or the third mode, two transmitting lines TXE+ and TXE− respectively connected to transmitters TX+ and TX− and two receiving lines RXE+ and RXE− respectively connected to receivers RX+ and RX− may perform a sensing operation based on the mutual-capacitance method, in the sensing area SA. 
     As described above, the touch panel controller  200  in the present exemplary embodiment may sense the sensing area SA having the substantially the same size while using a reduced number of sensor lines, thus reducing power consumption. 
     In the description below, one or more modified exemplary embodiments of driving a touch panel with a touch panel controller will be described with reference to  FIGS.  9  and  10   . 
       FIGS.  9  and  10    are diagrams illustrating a method of driving a touch panel with a touch panel controller according to exemplary embodiments of the present inventive concept. 
     Referring to  FIG.  9   , a sensing device may include the touch panel controller  200  and a touch panel  900  including first sensor electrodes  910  and second sensor electrodes  920 . When the sensing device operates in the second mode or the third mode, the touch panel controller  200  may select a  2 nd second sensor electrode  922  of the second sensor electrodes  920  of the touch panel  900  as a first transmitting electrode TXE+ connected to a first transmitter TX+, and may select an n−1st second sensor electrode  928  of the second sensor electrodes  920  as a second transmitting electrode TXE− connected to a second transmitter TX−. 
     The touch panel controller  200  may select 1st and 3rd second sensor electrodes  921  and  923  adjacent to the first transmitting electrode TXE+ (the 2nd second sensor electrode  922 ) as first receiving electrodes RXE+ respectively connected to first receivers RX+. Each of the first receiving electrodes RXE+ may form the mutual capacitance C M  with the first transmitting electrode TXE+. Additionally, the touch panel controller  200  may select n−2nd and nth sensor electrodes  927  and  929  adjacent to the second transmitting electrode TXE− (the n−1st second sensor electrode  928 ) as second receiving electrodes RXE− respectively connected to second receivers RX−. Each of the second receiving electrodes RXE− may form the mutual capacitance CM with the second transmitting electrode TXE−. 
     When a gap between the first transmitting electrode TXE+ and the second transmitting electrode TXE− is relatively large as illustrated in  FIG.  9   , the touch panel controller  200  may not select a shielding electrode. 
     Thus, when only detecting whether a user input occurs, a minimum number of sensor electrodes may be driven using the driving method illustrated in  FIG.  9   . Accordingly, power consumption may be reduced, and a user input may be detected instantly. 
     Referring to  FIG.  10   , a sensing device may include the touch panel controller  200  and a touch panel  1000  including first sensor electrodes  1010  and second sensor electrodes  1020 . When the sensing device operates in the second mode or the third mode, the touch panel controller  200  may select a 1st second sensor electrode  1021  of the second sensor electrodes  1020  of the touch panel  1000  as a first transmitting electrode TXE+ connected to a first transmitter TX+, and may select a 7th second sensor electrode  1027  of the second sensor electrodes  1020  as a second transmitting electrode TXE− connected to a second transmitter TX−. Accordingly, the 1st second sensor electrode  1021  and the 7th second sensor electrode  1027  may be configured as a pair of transmitting electrodes TXE+ and TXE−. 
     The touch panel controller  200  may select 2nd and 3rd second sensor electrodes  1022  and  1023  as first receiving electrodes RXE+ respectively connected to first receivers RX+, and forming the mutual capacitance C M  with the first transmitting electrode TXE+ (the 1st second sensor electrode  1021 ). Additionally, the touch panel controller  200  may select 5th, 6th, 8th, and 9th second sensor electrodes  1025 ,  1026 ,  1028 , and  1029  as second receiving electrodes RXE− respectively connected to second receivers RX−, and forming the mutual capacitance C M  with the second transmitting electrode TXE− (the 7th second sensor electrode  1027 ). 
     Using the above-described method, the touch panel controller  200  may include the plurality of receiving electrodes RXE+ and RXE−, thus increasing a magnitude of a sensing signal. Thus, using the driving method illustrated in  FIG.  10   , a user input may be detected while significantly reducing an effect from noise and increasing sensing sensitivity. 
       FIGS.  11  to  13    are diagrams illustrating a method of driving a touch panel with a touch panel controller according to exemplary embodiments of the present inventive concept. 
       FIG.  11    is a diagram illustrating a method of driving a touch panel  1100  when a sensing device operates in the first mode, and  FIGS.  12  and  13    are diagrams illustrating a method of driving touch panels  1200  and  1300  when the sensing device operates in the second mode and the third mode. In the exemplary embodiment illustrated in  FIGS.  11  to  13   , the sensing device may perform a sensing operation based on a self-capacitance method. 
     Referring to  FIG.  11   , the touch panel  1100  may include first sensor electrodes  1110  and second sensor electrodes  1120 . When the sensing device operates in the first mode, the touch panel controller  200  may select the second sensor electrodes  1120  as receiving electrodes RXE respectively connected to receivers RX. 
     The touch panel controller  200  may receive an electrical signal output from the receiving electrodes RXE and may detect whether a user input occurs and a position (a coordinate value) in which the user input occurs. 
     Referring to  FIG.  12   , when the sending device operates in the second mode or the third mode, the touch panel controller  200  may select at least a pair of receiving electrodes RXE+ and RXE− from among first sensor electrodes  1210  of the touch panel  1200 . Each pair of the receiving electrodes RXE+ and RXE− may include a first receiving electrode RXE+ outputting first sensing signals OUT 2  and OUT 4  through a first receiver RX+ and a second receiving electrode RXE− outputting second sensing signals OUT 1  and OUT 3  through a second receiver RX−. The first sensing signals OUT 2  and OUT 4  may correspond to a change in a first self capacitance produced by the first receiving electrode RXE+. The second sensing signals OUT 1  and OUT 3  may correspond to a change in a second self capacitance produced by the second receiving electrode RXE−. The first sensing signals OUT 2  and OUT 4  and the second sensing signals OUT 1  and OUT 3  may have the same magnitude V sig , and may have a phase difference of 180 degrees therebetween. The user input may be detected by using a summation signal of the first sensing signals OUT 2  and OUT 4  and the second sensing signals OUT 1  and OUT 3 . 
     At least one sensor electrode may be disposed between the first receiving electrode RXE+ and the second receiving electrode RXE−. The touch panel controller  200  may select at least one of the at least one sensor electrode disposed between the first receiving electrode RXE+ and the second receiving electrode RXE− as a shielding electrode. In an exemplary embodiment of the present inventive concept, the touch panel controller  200  may connect one of the at least one sensor electrode disposed between the first receiving electrode RXE+ and the second receiving electrode RXE− adjacent to each other to a ground power, or may float it, to configure the shielding electrode. 
     Alternatively, the touch panel controller  200  may select second sensor electrodes orthogonal to the first sensor electrodes  1210  as the receiving electrodes RXE respectively connected to receivers RX. 
     Referring to  FIG.  13   , when the sensing device operates in the second mode or the third mode, the touch panel controller  200  may select at least a pair of the receiving electrodes RXE+ and RXE− from among first sensor electrodes  1310  of the touch panel  1300 . Each pair of the receiving electrodes RXE+ and RXE− may include a plurality of first receiving electrodes RXE+ and a plurality of second receiving electrodes RXE−. 
     The first receiving electrodes RXE+ may output first sensing signals OUT 3 , OUT 4 , OUT 7 , and OUT 8  through receivers RX+. The second receiving electrodes RXE− may output second sensing signals OUT 1 , OUT 2 , OUT 5 , and OUT 6  through receivers RX−. The first sensing signals OUT 3 , OUT 4 , OUT 7 , and OUT 8  and the second sensing signals OUT 1 , OUT 2 , OUT 5 , and OUT 6  may have the same magnitude V sig , and may have a phase difference of 180 degrees therebetween. 
     At least one sensor electrode may be disposed between the first receiving electrodes RXE+ and the second receiving electrodes RXE− in each pair of the receiving electrodes. The touch panel controller  200  may select at least one of the at least one sensor electrode as a shielding electrode. As the shielding electrode is connected to a ground power or floats, the shielding electrode may remove interference between the first receiving electrodes RXE+ and the second receiving electrodes RXE−. 
     Alternatively, the touch panel controller  200  may select second sensor electrodes orthogonal to the first sensor electrodes  1310  as the receiving electrodes RXE. 
       FIG.  14    is a block diagram illustrating an electronic device including a sensing device according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG.  14   , an electronic device  1400  may include a display device  1410 , an input and output device  1420 , a memory  1430 , a processor  1440 , a port  1450 , and the like. For example, the electronic device  1400  may further include a wired and wireless communication device, a power device, or the like. Among the elements illustrated in  FIG.  14   , the port  1450  may be implemented as a device provided for the electronic device  1400  to communicate with a video card, a sound card, a memory card, or the like. The electronic device  1400  may include a general desktop computer and a laptop computer, and may also include a smartphone, a tablet personal computer (PC), a smart wearable device, or the like. 
     The processor  1440  may perform a certain calculation and may process a command word, a task, or the like. The processor  1440  may be implemented as a central processing unit (CPU), a microcontroller unit (MCU), a system-on-chip (SoC), or the like, and may communicate with the display device  1410 , the input and output device  1420 , and the memory  1430 , as well as other devices connected to the port  1450 , through a bus  1460 . The processor  1440  may be integrated with the processor  230  of the display device described with reference to  FIGS.  1  to  13   . 
     The memory  1430  may be implemented as a storage medium storing data required for operation of the electronic device  1400 , multimedia data, or the like. The memory  1430  may include a volatile memory, or a non-volatile memory such as a flash memory or the like. The memory  1430  may also include at least one of a solid state drive (SSD), a hard disk drive (HDD), and an optical disk drive (ODD) as a storage device. The input and output device  1420  may include an input device such as a keyboard, a mouse, a touchscreen, or the like, provided to a user, and an output device such as a display, an audio output unit, or the like. 
     The display device  1410  may be connected to the processor  1440  by the bus  1460  or another communication means. The display device  1410  may be implemented in the electronic device  1400  according to the aforementioned exemplary embodiments described with reference to  FIGS.  1  to  13   . 
     According to the aforementioned exemplary embodiments of the present inventive concept, the touch panel controller of the sensing device may remove noise signals flowing into the touch panel from the display panel, thus improving sensing sensitivity. 
     The touch panel controller may improve sensing sensitivity in relation to an object having the same area. The touch panel controller may also remove noise signals flowing into the display panel from the touch panel, thus improving image quality of the display panel. 
     The sensing device may decrease the number of sensor electrodes for detecting a user input, thus significantly reducing power consumption. The sensing device may also drive a minimal number of sensor electrodes and may swiftly detect whether a user input occurs. 
     While the present inventive concept has been shown and described with reference to exemplary embodiments thereof, it will be apparent to those of ordinary skill in the art that modifications and variations in form and details could be made thereto without departing from the spirit and scope of the present inventive concept as set forth by the appended claims.