Method and apparatus for discriminating between user interactions

• US 10,437,381 B2
• Filed: 12/20/2017
• Issued: 10/08/2019
• Est. Priority Date: 01/17/2007
• Status: Active Grant

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Wright, David G.
• Primary Examiner(s): Cerullo, Liliana
• Application Number:
  US15/849,204
• Publication Number:
  US 20180113560A1
• Time in Patent Office: 657 Days
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

Abstract

Described herein is a car entertainment and navigation system that includes a user interface controller, a detecting circuit, and a selection circuit. The detecting circuit includes a selection circuit, capacitance-sensing circuitry to determine a location of a touch proximate to one or more electrodes of the touch screen display based on capacitance measurements of a plurality of electrodes of the touch screen made during a first mode of operation of the detecting circuit, and user-detecting circuitry to determine a location of a user corresponding to the touch based on signal measurements of a capacitively-coupled signal at the one or more electrodes made during a second mode of operation of the detecting circuit. The selection circuit is configurable to selectively couple the capacitance-sensing circuitry to the plurality of electrodes during the first mode and selectively coupling the user-detecting circuitry to the one or more electrodes during the second mode.

Claims

1. A car entertainment and navigation system comprising:

a user interface controller configured to output graphical display data to a touch screen display of a car; and

a detecting circuit coupled to the user interface controller, the detecting circuit comprising;

capacitance-sensing circuitry coupled to a plurality of electrodes of the touch screen display, the capacitance-sensing circuitry to determine a location of a touch proximate to one or more electrodes of the plurality of electrodes based on capacitance measurements of the plurality of electrodes of the touch screen display made during a first mode of operation of the detecting circuit; and

user-detecting circuitry coupled to the one or more electrodes, the user-detecting circuitry to determine a location of a user corresponding to the same touch proximate to the same one or more electrodes of the plurality of electrodes based on signal measurements of a capacitively-coupled signal at the one or more electrodes made by the same touch proximate to the same one or more electrodes of the plurality of electrodes during a second mode of operation of the detecting circuit.

2. The car entertainment and navigation system of claim 1, wherein the detecting circuit is configured to receive a signal from a device coupled to the car entertainment and navigation system and determine that the car is in motion based on the signal.

3. The car entertainment and navigation system of claim 1, wherein the detecting circuit is configured to receive a signal from a car system and determine a state of the car based on the signal.

4. The car entertainment and navigation system of claim 1, wherein the user-detecting circuitry further comprises a frequency detector circuit to detect a frequency of the capacitively-coupled signal.

5. The car entertainment and navigation system of claim 4, wherein the frequency detector circuit comprises a phase-locked loop (PLL).

6. The car entertainment and navigation system of claim 5, wherein the frequency detector circuit further comprises an amplifier coupled to the PLL.

7. The car entertainment and navigation system of claim 4, wherein the frequency detector circuit comprises a demodulator that is configured to demodulate a carrier frequency to detect a modulated frequency on the carrier frequency, wherein the modulated frequency corresponds to a specific location of the user.

8. The car entertainment and navigation system of claim 1, wherein the first mode is a touch sensing mode and the second mode is a user sensing mode, wherein, when the touch is detected proximate to the one or more electrodes in the touch sensing mode, the same one or more electrodes are reconfigured to sense the capacitively-coupled signal in the user sensing mode.

9. The car entertainment and navigation system of claim 1, wherein the capacitance-sensing circuitry and the user-detecting circuitry operate sequentially in the first mode and the second mode, respectively.

10. The car entertainment and navigation system of claim 1, further comprises a selection circuit configurable to selectively couple the capacitance-sensing circuitry to the one or more electrodes in the first mode and selectively couple the user-detecting circuitry to the one or more electrodes in the second mode.

11. The car entertainment and navigation system of claim 10, wherein the capacitance-sensing circuitry comprises a single capacitance sensor coupled to the selection circuit.

12. The car entertainment and navigation system of claim 11, wherein the single capacitance sensor comprises at least one of a relaxation oscillator, a sigma-delta modulation circuit, a successive approximation circuit, a voltage phase shift measurement circuit, a resistor-capacitor charge timing circuit, a capacitive bridge divider circuit, a charge transfer circuit, or a charge-accumulation circuit.

13. The car entertainment and navigation system of claim 10, wherein the capacitance-sensing circuitry comprises a plurality of capacitance sensors coupled to the selection circuit.

14. The car entertainment and navigation system of claim 1, wherein the user interface controller comprises a logic block configured to receive a digital code from the capacitance-sensing circuitry and an indication of the location of the user from the user-detecting circuitry, wherein the indication of the location is either a driver seat of the car or a passenger seat of the car.

15. The car entertainment and navigation system of claim 14, wherein the logic block is configured to receive a signal from a device coupled to the car entertainment and navigation system and determine that the car is in motion based on the signal.

16. An integrated circuit comprising:

capacitance-sensing circuitry to determine a location of a touch proximate to one or more electrodes of a plurality of electrodes based on capacitance measurements of the plurality of electrodes of a touch screen made during a first mode of operation of the integrated circuit; and

user-detecting circuitry to determine a location of a user corresponding to the same touch proximate to the one or more electrodes based on signal measurements of a capacitively-coupled signal at the one or more electrodes made by the same touch proximate to the same one or more electrodes of the plurality of electrodes during a second mode of operation of the integrated circuit; and

a multiplexer coupled to the capacitance-sensing circuitry and the user-detecting circuitry, wherein multiplexer is configurable to selectively couple the capacitance-sensing circuitry to the plurality of electrodes during the first mode and selectively coupling the user-detecting circuitry to the one or more electrodes during the second mode.

17. The integrated circuit of claim 16, further comprising a user interface controller coupled to the capacitance-sensing circuitry and the user-detecting circuitry, wherein the user interface controller is configured to receive a signal from a device coupled to the integrated circuit and determine that a car is in motion based on the signal.

18. A touch screen device comprising:

a touch screen display comprising electrodes and display elements;

a processing device coupled to the touch screen display, wherein the processing device comprises;

a user interface controller coupled to the touch screen display;

a detecting circuit coupled to the user interface controller, the detecting circuit comprising a capacitance measurement circuit and a user-detector circuit; and

a selection circuit coupled to the detecting circuit, wherein the selection circuit is configurable to selectively couple the capacitance measurement circuit to one or more of the electrodes during a first mode and selectively couple the user-detector circuit to the one or more electrodes during a second mode, wherein;

the capacitance measurement circuit is configured to determine a location of a touch proximate to the one or more electrodes of a plurality of electrodes based on capacitance measurements made during the first mode; and

the user-detector circuit is configured to determine a location of a user corresponding to the same touch based on signal measurements of a capacitively-coupled signal at the same one or more electrodes of the plurality of electrodes made during the second mode.

19. The touch screen device of claim 18, wherein the processing device is configured to control a first drive circuit located at a driver seat of a car and a second drive circuit located at a passenger seat of the car.

20. The touch screen device of claim 18, wherein the detecting circuit is configured to receive a signal from a speedometer and determine that a car is in motion based on the signal.