Display apparatus that changes touch-panel driving frequency when it matches display-panel driving frequency and control method thereof
A display apparatus is disclosed that includes a touch panel, a display panel, and a touch integrated circuit (IC) configured to determine whether a first frequency, which is a driving frequency of the display panel, matches a second frequency, which is a driving frequency of the touch panel, and change the second frequency to a third frequency that is different from the first frequency when the first frequency matches the second frequency.
1 . A display apparatus comprising:
a touch panel;
a display panel; and
a touch integrated circuit (IC) configured to determine whether a first frequency, which is a driving frequency of the display panel, matches a second frequency, which is a driving frequency of the touch panel, and change the second frequency to a third frequency that is different from the first frequency when the first frequency matches the second frequency,
wherein the touch IC changes the second frequency by changing an analog parameter or a digital bit stored in the touch IC.
2 . The display apparatus of claim 1 , wherein the first frequency is determined based on a display mode of the display panel.
3 . The display apparatus of claim 2 , further comprising a processor connected to the display panel and configured to recognize a change in information about the first frequency, wherein the touch IC receives information about the first frequency from the processor.
4 . The display apparatus of claim 2 , wherein the display panel is directly connected to the touch IC and the touch IC is further configured to monitor a change in information about the first frequency.
5 . The display apparatus of claim 3 , wherein the touch IC is further configured to determine whether a user touch signal includes harmonic noise based on whether the first frequency matches the second frequency.
6 . The display apparatus of claim 5 , wherein, when it is determined that the user touch signal includes the harmonic noise,
the touch IC changes the second frequency to the third frequency by changing the second frequency to a hopping frequency selected from a plurality of predetermined hopping frequencies by changing the analog parameter.
7 . The display apparatus of claim 5 , wherein, when it is determined that the user touch signal includes the harmonic noise, the touch IC changes the second frequency to the third frequency by dithering the second frequency to a predetermined frequency band by changing the digital bit.
8 . The display apparatus of claim 7 , wherein the predetermined frequency band is within a range of and including 233 kHz to 264 kHz.
9 . The display apparatus of claim 3 , wherein the touch IC and the processor are disposed on a printed board,
the touch panel and the touch IC are connected to each other by a plurality of sensing signal lines and a plurality of driving signal lines,
the display panel and the processor are connected to each other by a mobile industry processor interface (MIPI) transfer line, and
the plurality of sensing signal lines and the plurality of driving signal lines at least partially intersect the MIPI transfer line.
10 . A method of controlling a display apparatus comprising a display panel and a touch panel, the method comprising:
receiving, by a touch integrated circuit (IC) connected to the touch panel, information about a first frequency, which is a driving frequency of the display panel;
determining, by the touch IC, whether the first frequency matches a second frequency, which is a driving frequency of the touch panel; and
changing, by the touch IC, the second frequency to a third frequency that is different from the first frequency when the first frequency matches the second frequency,
wherein the receiving of the information about the first frequency comprises switching a first display mode of the display panel to a second display mode; and
receiving, by the touch IC, information about the first frequency, which is determined based on the second display mode of the display panel.
11 . The method of claim 10 , wherein the receiving of the information about the first frequency comprises:
receiving, by the touch IC, the information about the first frequency from a processor configured to recognize a change in the information about the first frequency, which is determined based on a mode of the display panel.
12 . The method of claim 10 , further comprising monitoring, by the touch IC that is directly connected to the display panel by an external pin, a change in the information about the first frequency.
13 . The method of claim 11 , wherein the determining of whether the first frequency matches the second frequency comprises determining whether a user touch signal includes harmonic noise based on whether the first frequency matches the second frequency.
14 . The method of claim 13 , wherein the changing of the second frequency to the third frequency comprises changing the second frequency to the third frequency by changing the second frequency to a hopping frequency selected from a plurality of predetermined hopping frequencies when the user touch signal includes the harmonic noise.
15 . The method of claim 14 , wherein the changing of the second frequency to the third frequency comprises changing the second frequency to the third frequency by changing an analog parameter stored in the touch IC.
16 . The method of claim 13 , wherein the changing of the second frequency to the third frequency comprises changing the second frequency to the third frequency by dithering the second frequency to a predetermined frequency band when the user touch signal includes the harmonic noise.
17 . The method of claim 16 , wherein the changing of the second frequency to the third frequency comprises changing the second frequency to the third frequency by changing a digital bit stored in the touch IC.