Touch driving circuit, touch display device, and touch driving method thereof

Abstract

A touch display device includes a display panel including a plurality of touch electrodes, a touch driving circuit configured to operate in a first mode and a second mode according to a touch sensing type and detect a touch presence or a touch position based on a touch sensing signal received from the plurality of touch electrodes, and a timing controller. The timing controller can generate a first type of touch synchronization signal having a first level for displaying a first image during a first display period of a first display frame and a second level for detecting the touch position during a touch driving period of the first display frame, and supply the first type of touch synchronization signal to the touch driving circuit to operate the touch driving circuit in the first mode.

What is claimed is: 
     
         1 . A touch display device, comprising:
 a display panel including a plurality of touch electrodes;   a touch driving circuit configured to:
 operate in a first mode and a second mode according to a touch sensing type, and 
 detect a touch presence or a touch position based on a touch sensing signal received from the plurality of touch electrodes; and 
   a timing controller configured to:
 generate a first type of touch synchronization signal having a first level for displaying a first image during a first display period of a first display frame and a second level for detecting the touch position during a touch driving period of the first display frame, and supply the first type of touch synchronization signal to the touch driving circuit to operate the touch driving circuit in the first mode, and 
 generate a second type of touch synchronization signal having the first level for displaying a second image during a second display period of a second display frame and the second level for detecting the touch presence during a touch driving period of the second display frame, and supply the second type of touch synchronization signal to the touch driving circuit to operate the touch driving circuit in the second mode, 
   wherein the touch driving period of the second display frame for the second mode is different than the touch driving period of the first display frame for the first mode, or the second display period of the second display frame for the second mode is different than the first display period of the first display frame for the first mode.   
     
     
         2 . The touch display device according to  claim 1 , wherein the first mode is a mode for detecting the touch position, and the second mode is a mode for detecting the touch presence. 
     
     
         3 . The touch display device according to  claim 1 , wherein the touch driving period of the second display frame for the second mode is shorter than the touch driving period of the first display frame for the first mode. 
     
     
         4 . The touch display device according to  claim 1 , wherein the second display period of the second display frame for the second mode is longer than the first display period of the first display frame for the first mode. 
     
     
         5 . The touch display device according to  claim 1 , wherein in a long horizontal blank (LHB) driving operation in which two or more touch driving periods are included in one display frame period,
 the first mode includes two or more touch driving periods in one display frame period, and the second mode includes a shorter touch driving period than the first mode within one display frame period.   
     
     
         6 . The touch display device according to  claim 5 , wherein the second mode includes one touch driving period within one display frame period. 
     
     
         7 . The touch display device according to  claim 5 , wherein the touch driving period has a same time interval in the first mode and the second mode. 
     
     
         8 . The touch display device according to  claim 7 , wherein the same time interval is 60 Hz. 
     
     
         9 . The touch display device according to  claim 1 , wherein the timing controller turns off a memory for temporarily storing digital image data supplied to the display panel in the second mode. 
     
     
         10 . The touch display device according to  claim 1 , wherein the timing controller transmits a data packet to the touch driving circuit through a point-to-point interface, transmits the data packet through paired signal lines in the first mode, and transmits the data packet through one signal line of the paired signal lines in the second mode. 
     
     
         11 . The touch display device according to  claim 1 , wherein in the second mode,
 an uplink signal is transmitted from the display panel to a stylus during a first touch driving period, and   a downlink signal is received from the stylus during a second touch driving period.   
     
     
         12 . The touch display device according to  claim 11 , wherein the uplink signal includes a beacon signal to drive the stylus and a ping signal for synchronization. 
     
     
         13 . The touch display device according to  claim 11 , wherein the downlink signal is a signal including at least one of the position, a slope, and additional information of the stylus. 
     
     
         14 . The touch display device according to  claim 1 , wherein the timing controller is further configured to:
 in response to sensing a touch presence while in the second mode, transition the touch display device from the second mode to the first mode for sensing the touch position.   
     
     
         15 . The touch display device according to  claim 1 , wherein in the second mode, a same touch driving signal is simultaneously supplied to all of the plurality of touch electrodes in the display panel. 
     
     
         16 . The touch display device according to  claim 1 , wherein a pulse of the first type of touch synchronization signal during the first display frame in the first mode is shorter than a pulse of the second type of touch synchronization signal during the second display frame in the second mode.