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

• US 9,285,912 B2
• Filed: 05/13/2015
• Issued: 03/15/2016
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kwon, Keuksang, Cho, Namkyun
• Primary Examiner(s): Amadiz, Rodney
• Application Number:
  US14/711,561
• Publication Number:
  US 20150346887A1
• Time in Patent Office: 307 Days
• Field of Search: 345/156, 345173-178, 178 1801- 1811
• US Class Current: 1/1
• 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 touch sensing display device supporting a pixel driving period and a touch driving period in each frame period, the device comprising:

a display panel having data lines and touch sensing lines, the data lines coupled to pixels of the display panel;

a data driving circuit to drive data signals onto the data lines during the pixel driving period of the frame period, the data driving circuit powered by a first power supply voltage VDD or VCC;

a touch readout circuit to generate touch data from signals of the touch sensing lines during the touch driving period of the frame period, the touch driving period distinct from the pixel driving period; and

a first power controller to cut off the first power supply voltage VDD or VCC from powering the data driving circuit during the touch driving period of the frame period.

2. The touch sensing display device of claim 1, wherein the touch readout circuit is powered by a second power supply voltage, and further comprising:

a second power controller to cut off the second supply power voltage from powering the touch readout circuit during the pixel driving period of the frame period.

3. The touch sensing display device of claim 1, further comprising:

a timing controller to generate a shut down control signal,

wherein the first power controller cuts off the first power supply voltage VDD or VCC powering the data driving circuit responsive to the shut down control signal.

4. The touch sensing display device of claim 3, wherein the timing controller generates a wake up signal, wherein the first power controller applies the first power supply voltage VDD or VCC powering the data driving circuit responsive to the wake up signal.

5. The touch sensing display device of claim 1, wherein the first power supply voltage VDD or VCC that is cut off during the touch driving period of the frame period is a power supply voltage for an analog portion of the data driving circuit.

6. The touch sensing display device of claim 1, wherein the first power supply voltage VDD or VCC that is cut off during the touch driving period of the frame period is a power supply voltage for a digital portion of the data driving circuit.

7. The touch sensing display device 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 VDD or VCC that is cut off during the touch driving period of the frame period is cut off to the output circuit but is not cut off to the DAC.

8. The touch sensing display device of claim 7, wherein the data driving circuit comprises a data sampler and de-serializer, and wherein the power controller receives a shutdown control signal from the data sampler and de-serializer of the data driving circuit and cuts off the first power supply voltage VDD or VCC from powering the output circuit of the data driving circuit based on the shutdown control signal.

9. The touch sensing display device of claim 1, further comprising:

common electrode patterns corresponding to the pixels, the common electrode patterns driven with at least one touch driving signal during the touch driving period and driven with a common voltage during the pixel driving period.

10. A touch sensing display device supporting a pixel driving period and a touch driving period in each frame period, the device comprising:

a display panel having data lines and touch sensing lines, the data lines coupled to pixels of the display panel;

a data driving circuit to drive data voltages onto the data lines during the pixel driving period of the frame period;

a touch readout circuit to generate touch data from signals of the touch sensing lines during the touch driving period of the frame period, the touch driving period distinct from the pixel driving period, the touch readout circuit powered by a first power supply voltage; and

a first power controller to cut off the first power supply voltage from powering the touch readout circuit during the pixel driving period of the frame period.

11. The touch sensing display device of claim 10, wherein the data driving circuit is powered by a second power supply voltage, and further comprising:

a second power controller to cut off the second power supply voltage from powering the data driving circuit during the touch driving period of the frame period.

12. The touch sensing display device of claim 10, further comprising:

a timing controller to generate a timing division synchronization signal indicative of whether the frame period is in the pixel driving period or the touch driving period;

wherein the first power controller cuts off the first power supply voltage of the touch readout circuit responsive to the timing division synchronization signal.

13. The touch sensing display device of claim 10, wherein the first power supply voltage that is cut off during the pixel driving period of the frame period is a power supply voltage for an analog portion of the touch readout circuit.

14. The touch sensing display device of claim 10, wherein the first power supply voltage that is cut off during the pixel driving period of the frame period is a power supply voltage for a digital portion of the touch readout circuit.

15. The touch sensing display device of claim 10, further comprising:

common electrode patterns corresponding to the pixels, the common electrode patterns driven with at least one touch driving signal during the touch driving period and driven with a common voltage during the pixel driving period.

16. A method of operation in a touch sensing display device, comprising:

driving, by a data driving circuit powered by a first power supply voltage VDD or VCC, data voltages onto data lines of a display panel during a pixel driving period of a frame period, the data lines coupled to pixels of the display panel;

generating touch data from signals of touch sensing lines of the display panel during a touch driving period of the frame period, the touch driving period distinct from the pixel driving period; and

cutting off the first power supply voltage VDD or VCC from powering the data driving circuit during the touch driving period of the frame period.

17. The method of claim 16, further comprising:

generating a shut down control signal at a timing controller,

wherein the first power supply voltage VDD or VCC powering the data driving circuit is cut off responsive to the shut down control signal.

18. The method of claim 17, further comprising:

generating a wake up signal at the timing controller,

wherein the first power supply voltage is applied to the data driving circuit responsive to the wake up signal.

19. The method of claim 16, wherein the touch data is generated by a touch readout circuit powered by a second power supply voltage, and the method further comprises:

cutting off the second power supply voltage from powering the touch driving circuit during the pixel driving period of the frame period.

20. The method of claim 19, further comprising:

generating a timing division synchronization signal indicative of whether the frame period is in the pixel driving period or the touch driving period;

wherein the second power supply voltage powering the touch readout circuit is cut off responsive to the timing division synchronization signal.