Touch detection device, display device including the same, and method of driving the same

1 . A touch detection device comprising:

touch electrodes comprising a plurality of driving electrodes and a plurality of sensing electrodes intersecting the plurality of driving electrodes to form a plurality of touch nodes;

a touch driving circuit electrically connected to the plurality of driving electrodes and configured to supply driving signals generated based on an orthogonal frequency division multiplexing (OFDM) scheme and a code division multiple access (CDMA) scheme to the plurality of driving electrodes; and

a touch sensing circuit electrically connected to the plurality of sensing electrodes and configured to sense a change in capacitance of each of the plurality of touch nodes through the plurality of sensing electrodes while the driving signals are supplied to the plurality of driving electrodes,

wherein the touch driving circuit drives the driving electrodes simultaneously in groups including at least a first group and a second group, supplies first driving signals based on a designated first frequency and first orthogonal codes set to correspond to the driving electrodes of the first group, respectively, to the driving electrodes of the first group, and supplies second driving signals based on a second frequency orthogonal to the first frequency and second orthogonal codes set to correspond to the driving electrodes of the second group, respectively, to the driving electrodes of the second group,

wherein the first orthogonal codes comprise first to nth codes associated with n driving electrodes, respectively, and wherein the first to nth codes comprise data based on Walsh codes orthogonal to one another,

wherein the touch sensing circuit acquires touch sensing data items through the sensing electrodes, performs a first operation of multiplying the touch sensing data items by the first frequency and the second frequency, performs a second operation of integrating the touch sensing data items after the first operation has been performed; and generates touch identification data corresponding to a change in capacitance of each of the touch nodes from the touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes, and

wherein the touch driving circuit comprises:

a frequency generator configured to generate a first sine wave based on the first frequency and a second sine wave based on the second frequency; and

a driving signal modulator configured to generate the first driving signals by multiplying the first sine wave by the first orthogonal codes and generate the second driving signals by multiplying the second sine wave by the second orthogonal codes,

wherein the touch sensing circuit comprises:

an amplifier configured to amplify first touch sensing data items sensed through the plurality of sensing electrodes;

an analog-to-digital converter configured to generate second touch sensing data items by converting the amplified first touch sensing data items into digital data;

an OFDM demodulator configured to perform the first operation and the second operation on the second touch sensing data items; and

a CDMA demodulator configured to generate touch identification data from the second touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes,

wherein the first orthogonal codes comprise first to fourth codes associated with four driving electrodes, respectively, and wherein the first to fourth codes have respective sets of code values of (1, 1, 1, 1); (1, −1, 1, −1); (1, 1, −1, −1); and (1, −1, −1, 1), and

wherein the second orthogonal codes are the same as the first orthogonal codes and are associated with four other driving electrodes, respectively.

2 . The device of claim 1 , wherein the driving electrodes of the first group comprises n driving electrodes, and wherein the driving electrodes of the second group comprises m driving electrodes, wherein n is equal to m.

3 . A display device comprising:

a display panel; and

a touch detection device,

wherein the touch detection device comprises:

touch electrodes comprising a plurality of driving electrodes and a plurality of sensing electrodes intersecting the plurality of driving electrodes to form a plurality of touch nodes;

a touch driving circuit electrically connected to the plurality of driving electrodes and configured to supply driving signals generated based on an orthogonal frequency division multiplexing (OFDM) scheme and a code division multiple access (CDMA) scheme to the plurality of driving electrodes; and

a touch sensing circuit electrically connected to the plurality of sensing electrodes and configured to sense a change in capacitance of each of the plurality of touch nodes through the plurality of sensing electrodes while the driving signals are supplied to the plurality of driving electrodes,

wherein the touch driving circuit drives the driving electrodes simultaneously in groups comprising a first group and a second group, supplies first driving signals based on a designated first frequency and first orthogonal codes set to correspond to the driving electrodes of the first group, respectively, to the driving electrodes of the first group, and supplies a second multi-drive signal based on a second frequency orthogonal to the first frequency and second orthogonal codes set to correspond to each of the second group of drive electrodes to the second group of drive electrodes,

wherein the first orthogonal codes comprise first to nth codes associated with n driving electrodes, respectively, and wherein the first to nth codes comprise data based on Walsh codes orthogonal to one another,

wherein the touch sensing circuit acquires touch sensing data items through the sensing electrodes, performs a first operation of multiplying the touch sensing data items by the first frequency and the second frequency, performs a second operation of integrating the touch sensing data items after the first operation has been performed; and generates touch identification data corresponding to a change in capacitance of each of the touch nodes from the touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes,

wherein the touch driving circuit comprises:

a frequency generator configured to generate a first sine wave based on the first frequency and a second sine wave based on the second frequency; and

a driving signal modulator configured to generate the first driving signals by multiplying the first sine wave by the first orthogonal codes and generate the second driving signals by multiplying the second sine wave by the second orthogonal codes,

wherein the touch sensing circuit comprises:

an amplifier configured to amplify first touch sensing data items sensed through the plurality of sensing electrodes;

an analog-to-digital converter configured to generate second touch sensing data items by converting the amplified first touch sensing data items into digital data;

an OFDM demodulator configured to perform the first operation and the second operation on the second touch sensing data items; and

a CDMA demodulator configured to generate touch identification data from the second touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes,

wherein the first orthogonal codes comprise first to fourth codes associated with four driving electrodes, respectively, and wherein the first to fourth codes have respective sets of code values of (1, 1, 1, 1); (1, −1, 1, −1); (1, 1, −1, −1); and (1, −1, −1, 1), and

wherein the second orthogonal codes are the same as the first orthogonal codes and are associated with four other driving electrodes, respectively.

4 . The display device of claim 3 , wherein the driving electrodes of the first group comprises n driving electrodes, and wherein the driving electrodes of the second group comprises m driving electrodes, wherein n is equal to m.

5 . A method of driving a display device comprising a display panel and a touch detection device, the method comprising:

supplying, by a touch driving circuit, driving signals generated based on an orthogonal frequency division multiplexing (OFDM) scheme and a code division multiple access (CDMA) scheme to a plurality of driving electrodes; and

sensing a change in capacitance of each of a plurality of touch nodes through a plurality of sensing electrodes while the driving signals are supplied to the plurality of driving electrodes,

wherein the supplying of the driving signals comprises:

driving the driving electrodes simultaneously in groups comprising a first group and a second group,

supplying first driving signals based on a designated first frequency and first orthogonal codes set to correspond to the driving electrodes of the first group, respectively, to the driving electrodes of the first group, and

supplying second driving signals based on a second frequency orthogonal to the first frequency and second orthogonal codes set to correspond to the driving electrodes of the second group, respectively, to the driving electrodes of the second group;

acquiring touch sensing data items through the sensing electrodes;

performing a first operation of multiplying the touch sensing data items by the first frequency and the second frequency;

performing a second operation of integrating the touch sensing data items after the first operation has been performed; and

generating touch identification data corresponding to a change in capacitance of each of the touch nodes from the touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes,

wherein the first orthogonal codes comprise first to nth codes associated with n driving electrodes, respectively, and wherein the first to nth codes comprise data based on Walsh codes orthogonal to one another, and

wherein the method further comprises:

generating, by a frequency generator, a first sine wave based on the first frequency and a second sine wave based on the second frequency;

generating, by a driving signal modulator, the first driving signals by multiplying the first sine wave by the first orthogonal codes and generating the second driving signals by multiplying the second sine wave by the second orthogonal codes

amplifying first touch sensing data items sensed through the plurality of sensing electrodes;

generating second touch sensing data items by analog-to-digital converting the amplified first touch sensing data items into digital data;

performing, by an OFDM demodulator, the first operation and the second operation on the second touch sensing data items; and

generating, by a CDMA demodulator, touch identification data from the second touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes,

wherein the first orthogonal codes comprise first to fourth codes associated with four driving electrodes, respectively, and wherein the first to fourth codes have respective sets of code values of (1, 1, 1, 1); (1, −1, 1, −1); (1, 1, −1, −1); and (1, −1, −1, 1), and

wherein the second orthogonal codes are the same as the first orthogonal codes and are associated with four other driving electrodes, respectively.

6 . The method of claim 5 , wherein the driving electrodes of the first group comprises n driving electrodes, and wherein the driving electrodes of the second group comprises m driving electrodes, wherein n is equal to m.

7 . An electronic device comprising:

touch electrodes comprising a plurality of driving electrodes and a plurality of sensing electrodes intersecting the plurality of driving electrodes to form a plurality of touch nodes;

a touch driving circuit electrically connected to the plurality of driving electrodes and configured to supply driving signals generated based on orthogonal carriers and a code division multiple access (CDMA) scheme to the plurality of driving electrodes; and

a touch sensing circuit electrically connected to the plurality of sensing electrodes and configured to sense a change in capacitance of each of the plurality of touch nodes through the plurality of sensing electrodes while the driving signals are supplied to the plurality of driving electrodes,

wherein the touch driving circuit drives the driving electrodes simultaneously in groups including at least a first group and a second group, supplies first driving signals based on a designated first frequency and first orthogonal codes set to correspond to the driving electrodes of the first group, respectively, to the driving electrodes of the first group, and supplies second driving signals based on a second frequency orthogonal to the first frequency and second orthogonal codes set to correspond to the driving electrodes of the second group, respectively, to the driving electrodes of the second group,

wherein the first orthogonal codes comprise first to nth codes associated with n driving electrodes, respectively, and wherein each of the first to nth codes comprises 1 which refers to non-inversion of a phase, or − 1 which refers to inversion of a phase,

wherein the touch sensing circuit acquires touch sensing data items through the sensing electrodes, performs a first operation of multiplying the touch sensing data items by the first frequency and the second frequency, performs a second operation of integrating the touch sensing data items after the first operation has been performed; and generates touch identification data corresponding to a change in capacitance of each of the touch nodes from the touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes, and

wherein the touch driving circuit comprises:

a frequency generator configured to generate a first sine wave based on the first frequency and a second sine wave based on the second frequency; and

a driving signal modulator configured to generate the first driving signals by multiplying the first sine wave by the first orthogonal codes and generate the second driving signals by multiplying the second sine wave by the second orthogonal codes,

wherein the touch sensing circuit comprises:

an amplifier configured to amplify first touch sensing data items sensed through the plurality of sensing electrodes;

an analog-to-digital converter configured to generate second touch sensing data items by converting the amplified first touch sensing data items into digital data;

an OFDM demodulator configured to perform the first operation and the second operation on the second touch sensing data items; and

a CDMA demodulator configured to generate touch identification data from the second touch sensing data items after the second operation has been performed using the first orthogonal codes and the second orthogonal codes,

wherein the first orthogonal codes comprise first to fourth codes associated with four driving electrodes, respectively, and wherein the first to fourth codes have respective sets of code values of (1, 1, 1, 1); (1, −1, 1, −1); (1, 1, −1, −1); and (1, −1, −1, 1), and

wherein the second orthogonal codes are the same as the first orthogonal codes and are associated with four other driving electrodes, respectively.