# US 11,907,476 B2 · Touch display device and touch sensing circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,907,476 B2 - Document ID: US11907476B2 - Status: Granted - Kind: B2 - Application number: 18/119,365 - Filed: 2023-03-09 - Published: 2023-07-06 - Granted: 2024-02-20 - Earliest claimed: 2020-12-16 - Assignees: LG Display Co., Ltd. - Applicants: LG Display Co., Ltd. - Inventors: Jeongseop Lee; SungUk Byun; Woorim Jeong; Hankyu Yang - Web page: https://patentgrep.com/patent/US11907476B2 ## CPC - G06F 3/0412: {Digitisers structurally integrated in a display} - G06F 3/0418: {for error correction or compensation, e.g. based on parallax, calibration or alignment} - G06F 3/04166: {Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving (Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184)} - G06F 3/04184: {Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally} - G06F 3/0443: {using a single layer of sensing electrodes} - G09G 3/20: for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix {no fixed position being assigned to or needed to be assigned to the individual characters or partial characters} - G09G 2310/08: Details of timing specific for flat panels, other than clock recovery - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract Embodiments of the present disclosure relate to a touch display device and a touch sensing circuit that apply a load-free driving signal having a phase difference or amplitude difference from the touch driving signal to a touch display panel. According to embodiments of the present disclosure, electromagnetic noise immunity may be improved and touch accuracy may be increased. The touch sensing circuit comprises: a touch driving circuit configured to output a pulse type touch driving signal to at least one of a plurality of touch electrodes disposed on a touch display panel; and a load-free driving signal output circuit configured to output at least one load-free driving signal having a frequency equal to a frequency of the touch driving signal and having a phase difference or amplitude difference from the touch driving signal. ## Claims ### Claim 1 A touch display device, comprising: a touch display panel including touch electrodes, data lines, gate lines, sensing lines, and sub-pixels; a data driving circuit connected to the data lines; a gate driving circuit connected to the gate lines; and a touch sensing circuit configured to output a touch driving signal to at least one touch electrode among the touch electrodes through at least one corresponding sensing line among the sensing lines, wherein a first driving signal is configured to be applied to at least one of the gate lines while the touch driving signal is output to the at least one touch electrode, and wherein the first driving signal has a same frequency as the touch driving signal and has a phase difference from the touch driving signal. ### Claim 2 (depends on 1) The touch display device of claim 1, wherein the gate driving circuit is configured to provide the first driving signal to the at least one of the gate lines. ### Claim 3 (depends on 1) The touch display device of claim 1, wherein a second driving signal is configured to be applied to at least one of the data lines, or a third driving signal is configured to be applied to one or more of the touch electrodes other than the at least one touch electrode, while the touch driving signal is output to the at least one touch electrode. ### Claim 4 (depends on 3) The touch display device of claim 3, wherein the data driving circuit is configured to provide the second driving signal to the at least one of the data lines. ### Claim 5 (depends on 3) The touch display device of claim 3, wherein the touch sensing circuit is configured to provide the third driving signal to the one or more of the touch electrodes other than the at least one touch electrode through one or more corresponding sensing lines among the sensing lines. ### Claim 6 (depends on 3) The touch display device of claim 3, wherein the touch driving signal and the second driving signal are signals whose phases are delayed compared to the first driving signal, and wherein the phase difference between the touch driving signal and the first driving signal is smaller than a phase difference between the second driving signal and the first driving signal. ### Claim 7 (depends on 6) The touch display device of claim 6, wherein the phase difference between the second driving signal and the first driving signal is less than a half of a wavelength of the touch driving signal. ### Claim 8 (depends on 3) The touch display device of claim 3, wherein the at least one touch electrode, a peripheral pattern adjacent to the at least one touch electrode, and the at least one corresponding sensing line electrically connecting the at least one touch electrode and the touch sensing circuit constitute a low pass filter, wherein a cutoff frequency of the low pass filter is determined according to a capacitance between the at least one touch electrode and the peripheral pattern and according to a resistance of the at least one corresponding sensing line, wherein the peripheral pattern includes at least one of the at least one the gate lines applied with the first driving signal, the at least one of the data lines applied with the second driving signal, and the one or more of the touch electrodes applied with the third driving signal, and wherein the cutoff frequency of the low pass filter becomes smaller as a phase difference between at least one of the first, second and third driving signals and the touch driving signal is greater than zero. ### Claim 9 (depends on 8) The touch display device of claim 8, wherein the peripheral pattern is disposed to overlap the at least one touch electrode. ### Claim 10 (depends on 3) The touch display device of claim 3, wherein a waveform of each of the touch driving signal and at least one of the first, second and third driving signals is a sine wave, a square wave, or a triangular wave. ### Claim 11 (depends on 1) The touch display device of claim 1, further comprising a phase delay circuit configured to delay a phase of the first driving signal. ### Claim 12 (depends on 11) The touch display device of claim 11, further comprising: a touch driving signal generator configured to generate the touch driving signal according to a touch driving generation signal and to output the generated touch driving signal to a touch driving circuit of the touch sensing circuit, wherein the phase delay circuit is disposed between the touch driving signal generator and one of the data driving circuit, the gate driving circuit, and the touch driving circuit. ### Claim 13 (depends on 1) The touch display device of claim 1, wherein the phase difference between the first driving signal and the touch driving signal is greater than zero and less than a half of a wavelength of the touch driving signal.