Time-division driving type touch sensing device and method for driving the same

• US 9,612,646 B2
• Filed: 01/29/2016
• Issued: 04/04/2017
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Cho, Namkyun, Kwon, Keuksang
• Primary Examiner(s): Amadiz, Rodney
• Application Number:
  US15/011,352
• Publication Number:
  US 20160147283A1
• Time in Patent Office: 431 Days
• Field of Search: 345156, 345173-178, 178 1801- 1811
• CPC Class Codes: G06F 1/3262 Power saving in digitizer or tablet
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: 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
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G09G 2310/065 Waveforms comprising zero voltage phase or pause
• CPC Class Codes: G09G 3/2092 Details of a display terminals using a flat panel, the details relating to the control arrangement of the display terminal and to the interfaces thereto suitable for both CRT and flat panel G09G5/003; specific for a CRT G09G1/165
• CPC Class Codes: G09G 3/3696 Generation of voltages supplied to electrode drivers

Abstract

A touch sensing display device supporting a pixel driving period and a touch driving period in each frame period. The device comprises a display panel having data lines and touch sensing lines, the data lines coupled to pixels of the display panel. A data driving circuit drives data signals onto the data lines during the pixel driving period of the frame period. A touch readout circuit generates touch data of signals of the touch sensing lines during the touch driving period of the frame period, the touch driving period distinct of the pixel driving period. A supply voltage of the data driving circuit can be cut off during the touch driving period, and a supply voltage of the touch readout circuit can be cut off during the pixel driving period.

Claims

1. A power controller for a touch sensing display device supporting a pixel driving period and a touch driving period in each frame period, the display device comprising a data driving circuit to drive data signals onto data lines of a display panel during the pixel driving period of each frame period and being powered by a first power supply voltage and a second power supply voltage, the power controller comprising:

a power control circuit to cut off the first power supply voltage and the second power supply voltage from powering the data driving circuit during the touch driving period of each frame period, touch data being generated from signals of touch sensing lines of the display panel during the touch driving period,

wherein the first power supply voltage that is cut off during the touch driving period of each frame period is a power supply voltage for an analog portion of the data driving circuit, and

wherein the second power supply voltage that is cut off during the touch driving period of each frame period is a power supply voltage for a digital portion of the data driving circuit.

2. The power controller of claim 1, wherein the power control circuit applies the first power supply voltage and the second power supply voltage to the data driving circuit responsive to a wake up signal provided by a timing controller.

3. The power controller of claim 1, wherein the data driving circuit comprises a digital-to-analog converter (DAC) to convert video data into analog data voltages and an output circuit to drive the analog data voltages onto the data lines, wherein the first power supply voltage that is cut off during the touch driving period of each frame period is cut off to the output circuit but is not cut off to the DAC.

4. The power controller of claim 1, wherein the touch driving period is distinct from the pixel driving period in each frame period.

5. A power controller for a touch sensing display device supporting a pixel driving period and a touch driving period in each frame period, the display device comprising a touch readout circuit to generate touch data from signals of touch sensing lines of the display panel during the touch driving period of each frame period, the touch readout circuit powered by a power supply voltage, the power controller comprising:

a power control circuit to cut off the power supply voltage from powering the touch readout circuit during the pixel driving period of each frame period, data signals being driven onto data lines of the display panel during the pixel driving period.

6. The power controller of claim 5, wherein the power control circuit cuts off the power supply voltage of the touch readout circuit responsive to a timing division synchronization signal provided by a timing controller.

7. The power controller of claim 5, wherein the power supply voltage that is cut off during the pixel driving period of each frame period is a power supply voltage for an analog portion of the touch readout circuit.

8. The power controller of claim 5, wherein the power supply voltage that is cut off during the pixel driving period of each frame period is a power supply voltage for a digital portion of the touch readout circuit.

9. The power controller of claim 5, wherein the touch driving period is distinct from the pixel driving period in each frame period.

10. A method of operation in a power controller for a touch sensing display device driven in a touch driving period and a pixel driving period in each frame period, the method comprising:

providing a first power supply voltage and a second power supply voltage to a data driving circuit during the pixel driving period of each frame period, the data driving circuit driving data voltages onto data lines of a display panel during the pixel driving period, the first power supply voltage being a power supply voltage for an analog portion of the data driving circuit, the second power supply voltage being a power supply voltage for a digital portion of the data driving circuit;

cutting off the first power supply voltage from powering the analog portion of the data driving circuit during the touch driving period of each frame period, touch data being generated from signals of touch sensing lines of the display panel during the touch driving period; and

cutting off the second power supply voltage from powering the digital portion of the data driving circuit during the touch driving period of each frame period.

11. The method of claim 10 wherein the first power supply voltage and the second power supply voltage are provided to the data driving circuit responsive to a wake up signal provided by a timing controller.

12. The method of claim 10, wherein the touch driving period is distinct from the pixel driving period in each frame period.

13. A method of operation in a power controller for a touch sensing display device driven in a touch driving period and a pixel driving period in each frame period, the method comprising:

providing a power supply voltage to a touch readout circuit during the touch driving period of each frame period, the touch readout circuit generating touch data from signals of touch sensing lines of a display panel during the touch driving period of each frame period; and

cutting off the power supply voltage from powering the touch readout circuit during the pixel driving period of each frame period, data signals being driven onto data lines of the display panel during the pixel driving period.

14. The method of claim 13, wherein the power supply voltage of the touch readout circuit is cut off responsive to a timing division synchronization signal provided by a timing controller.

15. The method of claim 13, wherein the power supply voltage that is cut off during the pixel driving period of each frame period is a power supply voltage for an analog portion of the touch readout circuit.

16. The method of claim 13, wherein the power supply voltage that is cut off during the pixel driving period of each frame period is a power supply voltage for a digital portion of the touch readout circuit.

17. The method of claim 13, wherein the touch driving period is distinct from the pixel driving period in each frame period.