Switching circuitry for touch sensitive display

• US 9,996,175 B2
• Filed: 11/21/2014
• Issued: 06/12/2018
• Est. Priority Date: 02/02/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Hotelling, Steven P., Yousefpor, Marduke, Chang, Shih Chang
• Primary Examiner(s): MERCEDES, DISMERY E
• Application Number:
  US14/550,686
• Publication Number:
  US 20150077375A1
• Time in Patent Office: 1,299 Days
• CPC Class Codes: G06F 1/3218 of display devices
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections

Abstract

A circuit for switching an LCD between display and touch modes is disclosed. The circuit can include one or more switches configured to switch one or more drive, sense, and data lines in LCD pixels according to the mode. During touch mode, the circuit switches can be configured to switch one or more drive lines to receive stimulation signals, one or more sense lines to transmit touch signals, and one or more data lines to transmit residual data signals. During display mode, the circuit switches can be configured to switch one or more drive lines and sense lines to receive common voltage signals and one or more data lines to receive data signals. The circuit can be formed around the border of the LCD chip or partially or fully on a separate chip.

Claims

1. An integrated touch screen comprising:

a plurality of pixels configured to;

display data on the touch screen during a display mode of the touch screen by applying first voltages to first electrodes and second voltages to second electrodes included in the plurality of pixels, each first electrode being one of a pixel electrode or a common electrode, and each second electrode being the other of the pixel electrode or the common electrode, and

sense one or more touch events on the touch screen during a touch mode of the touch screen;

a plurality of regions including first regions and second regions, each region including first electrodes of at least one of the plurality of pixels; and

switching circuitry configured to;

couple, using one or more first switches of the switching circuitry, the first electrodes of the first regions to a third voltage driven by a first circuitry during a first mode, the first mode associated with the touch mode, and

couple, using one or more second switches of the switching circuitry different from the first switches, the first electrodes of the second regions to a fourth voltage different from the third voltage driven by a second circuitry during the first mode, wherein the second circuitry is different from the first circuitry.

2. The integrated touch screen of claim 1, wherein the switching circuity is further configured to couple the second electrodes to a first common voltage source during the display mode with one or more conductive traces.

3. The integrated touch screen of claim 1, wherein each first and second region includes a touch plate.

4. The integrated touch screen of claim 1, wherein:

the one or more first switches of the switching circuitry decouple the first regions from the first circuitry during a second mode, and

the one or more second switches of the switching circuitry decouple the second regions from the second circuitry during the second mode.

5. The integrated touch screen of claim 1, wherein at least one of the plurality of pixels comprises a data line coupled to the first electrode of the at least one of the plurality of pixels, and the circuitry is configured to couple the data line to receive a data signal during the display mode.

6. The integrated touch screen of claim 1, wherein the first and second electrodes are located on a same layer of a stackup of the touch screen.

7. The integrated touch screen of claim 1,

wherein the plurality of regions further includes third regions, each third region including at least one of the plurality of pixels, and

wherein the circuity is further configured to:

concurrently couple the first electrodes of the first regions to the third voltage and couple first electrodes of the third regions to a voltage lower than the third voltage during the first mode.

8. The integrated touch screen of claim 7, wherein at least one third region is located adjacent to at least one first region and at least one second region.

9. The integrated touch screen of claim 1,

wherein the plurality of regions further includes third regions, each third region including at least one of the plurality of pixels, and

wherein circuitry is further configured to:

concurrently couple first electrodes of the third regions to ground and couple the first electrodes of the first regions to the third voltage during the first mode.

10. A method comprising:

displaying data on a touch screen during a display mode by applying first voltages to first electrodes and applying second voltages to second electrodes, wherein the first and second electrodes are included in a plurality of pixels, each first electrode is one of a pixel electrode or a common electrode, and each second electrode is the other of the pixel electrode or the common electrode, and

sensing one or more touch events on the touch screen during a touch mode, the sensing comprising;

coupling, with one or more first switches, the first electrode of at least one of the plurality of pixels included in first regions to a third voltage driven by a first circuitry during a first mode, the first mode associated with the touch mode; and

coupling, with one or more second switches, the first electrode of at least one of the plurality of pixels included in second regions to a fourth voltage different from the third voltage driven by a second circuitry during the first mode, the second circuitry different from the first circuitry.

11. The method of claim 10, further comprising coupling the second electrodes to a common voltage source during the display mode with one or more conductive traces.

12. The method of claim 10, further comprising:

decoupling, using the one or more first switches, the first electrode of the at least one of the plurality of pixels included in the first regions from the first circuitry during a second mode; and

decoupling, using the one or more first switches, first electrode of the at least one of the plurality of pixels included in the second regions from the second circuitry during the second mode.

13. The method of claim 10, further comprising coupling data lines to the first electrodes of the at least one of the plurality of pixels in the first and second regions to data signals during the display mode.

14. The method of claim 10, wherein the third voltage is same as the fourth voltage during the first mode.

15. The method of claim 10, further comprising:

concurrently coupling first electrodes of third regions, the third regions including at least one of the plurality of pixels, to ground and coupling the first electrodes of the at least one of the plurality of pixels included in the first regions to the third voltage during the first mode.

16. The method of claim 10, wherein coupling of the first electrode of the at least one of the plurality of pixels included in first regions is concurrent with coupling first electrodes of third regions to a voltage lower than the third voltage.

17. A non-transitory computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a device, cause the device to perform a method comprising:

displaying data on a touch screen during a display mode by applying first voltages to first electrodes and applying second voltages to second electrodes, wherein the first and second electrodes are included in a plurality of pixels, each first electrode is one of a pixel electrode or a common electrode, and each second electrode is the other of the pixel electrode or the common electrode, and

sensing one or more touch events on the touch screen during a touch mode, the sensing comprising;

coupling, using one or more first switches the first electrode of at least one of the plurality of pixels included in first regions to a third voltage driven by a first circuitry during a first mode, the first mode associated with the touch mode; and

coupling, using one or more second switches, the first electrode of at least one of the plurality of pixels included in second regions to a fourth voltage different from the third voltage driven by a second circuitry during-the first mode, the second circuitry different from the first circuitry.

18. An electronic device comprising:

A touch screen comprising a plurality of regions including first and second regions;

one or more first switches, the first switches configured to dynamically switch a first plurality of electrodes between first and second circuitry, wherein the first circuitry is separate and distinct from the second circuitry;

the plurality of first regions including the first plurality of electrodes, the first plurality of electrodes configured to receive a first voltage from the first circuitry during a first mode and receive a second voltage different from the first voltage from the second circuitry during a second mode,

wherein the first mode is associated with a touch mode of the electronic device; and

one or more second switches, the second switches configured to dynamically switch the second plurality of electrodes between third and fourth circuitry, wherein the third circuitry is separate and distinct from the fourth circuitry; and

the plurality of second regions including the second plurality of electrodes, the second plurality of electrodes configured to receive a third voltage different from the first voltage from the third circuitry during the first mode and receive a fourth voltage different from the third voltage and the second voltage, from the fourth circuitry during the second mode.

19. A method comprising:

during a first mode, the first mode associated with a touch mode of an electronic device, the electronic device comprising a touch screen comprising a plurality of regions including first and second regions, each region including a first plurality of electrodes and a second plurality of electrodes;

coupling, with one or more first switches, the first plurality of electrodes to receive a first voltage from a first circuitry, the first plurality of electrodes included in the first regions of the touch screen; and

coupling, with one or more second switches, the second plurality of electrodes to receive a third voltage different from the first voltage from a third circuitry, the second plurality of electrodes included in the second regions of the touch screen; and

during a second mode of the electronic device;

coupling, with the one or more first switches, the first plurality of electrodes to receive a second voltage different from the first voltage from a second circuitry, the second circuitry separate and distinct from the first circuitry; and

coupling, with the one or more second switches, the second plurality of electrodes to receive a fourth voltage, different from the second voltage and the third voltage, from a fourth circuitry, the fourth circuitry separate and distinct from the second circuitry.