Capacitive touch sensor and method

Patent metadata

Field	Value
Publication number	US-11716082-B2
Application number	US-202117547439-A
Country	US
Kind code	B2
Filing date	Dec 10, 2021
Priority date	May 6, 2014
Publication date	Aug 1, 2023
Grant date	Aug 1, 2023

Abstract

A capacitive touch sensor is disclosed for use with input signal. The capacitive touch sensor includes a number n of input/output lines. Each of the number n of input/output lines is electrically disconnected from every other of the number n of input/output lines. Each of the number n of input/output lines is arranged to cross every other of the number n of input/output lines. Each of a number β of positions includes one of the number n of input/output lines crossing another of the number n of input/output lines.

First claim

What is claimed is:

1. A method, the method comprising:
transmitting a first signal on a first input/output line of a capacitive touch sensor device, wherein each input/output line of the capacitive touch sensor device comprises a first portion extending in a first direction and a second portion extending in a second direction orthogonal to the first direction, the first portion coupled to the second portion, wherein each input/output line of the capacitive touch sensor device is arranged so that it is electrically disconnected from each other input/output line of the capacitive touch sensor device while crossing each other input/output line of the capacitive touch sensor device, wherein at least one of the first portion or the second portion of each input/output line crosses a respective other portion of each other input/output line, and wherein a number of input/output lines of the capacitive touch sensor device is greater than or equal to 3;
receiving a second signal on a second input/output line; and
determining that a touch event has occurred in the capacitive touch sensor device based on the second signal.

2. The method of claim 1 , wherein:
the capacitive touch sensor device includes a plurality of button areas, each button area corresponds to a location at which an input/output line crosses another input/output line, and wherein the plurality of button areas is equal to:
Σ 1 (n−1) x.

3. The method of claim 2 , wherein:
the second signal represents a change in capacitance.

4. The method of claim 3 , wherein:
the change in capacitance is responsive to a user touching one of the plurality of button areas.

5. The method of claim 1 , wherein:
each input/output line is coupled to a controller; and
each input/output line is configurable, by the controller, to transmit the first signal or receive the second signal.

6. The method of claim 5 , wherein:
the controller configures all other input/output lines other than the first input/output line to receive the second signal.

7. The method of claim 1 , wherein:
the second signal is above a threshold.

8. The method of claim 1 , wherein:
the capacitive touch sensor device includes a database having fault data stored therein and a fault determining component.

9. The method of claim 8 , further comprising:
detecting a respective parameter value for each input/output line; and
generating comparison values based on a comparison between the respective parameter value for each of then input/output line and the fault data; and
wherein the fault determining component is operable to output a fault signal based on the comparison values.

10. The method of claim 8 , wherein:
the fault data includes one of an open circuit, a short circuit, a damaged touch sensor, and an indication of overheating.

11. An apparatus, the apparatus comprising:
a capacitive touch sensor device including a plurality of input/output lines; and
a controller coupled to the plurality of input/output lines, the controller configured to:
transmit a first signal on a first input/output line of the plurality of input/output lines of the capacitive touch sensor device, wherein each input/output line of the plurality of input/output lines comprises a first portion extending in a first direction and a second portion extending in a second direction orthogonal to the first direction, the first portion coupled to the second portion, wherein each of the plurality of input/output lines is arranged so that it is electrically disconnected from each other one of the plurality of input/output lines while crossing each other one of the plurality of input/output lines, wherein at least one of the first portion or the second portion of each of the plurality of input/output lines crosses a respective other portion of each other one of the plurality of input/output lines, and wherein a number of input/output lines of the plurality of input/output lines is greater than or equal to 3;
receive a second signal on an input/output line of the plurality of input/output lines other than the first input/output line; and
determine that a touch event has occurred in the capacitive touch sensor device based on the second signal.

12. The apparatus of claim 11 , wherein:
the capacitive touch sensor device includes a plurality of button areas, each button area corresponds to a location at which one of the plurality of input/output lines crosses another one of the plurality of input/output lines, and wherein the plurality of button areas is equal to:
Σ 1 (n−1) x.

13. The apparatus of claim 12 , wherein:
the second signal represents a change in capacitance.

14. The apparatus of claim 13 , wherein:
the change in capacitance is responsive to a user touching one of the plurality of button areas.

15. The apparatus of claim 11 , wherein:
the plurality of input/output lines are each configurable, by the controller, to transmit the first signal or receive the second signal.

16. The apparatus of claim 15 , wherein:
the controller configures all of the plurality of input/output lines other than the first input/output line to receive the second signal.

17. The apparatus of claim 11 , wherein:
the second signal is above a threshold.

18. The apparatus of claim 11 , further comprising:
a database having fault data stored therein; and
a fault determining component.

19. The apparatus of claim 18 , wherein:
the controller is further configured to:
detect a respective parameter value for each of the plurality of input/output lines; and
generate comparison values based on a comparison between the respective parameter value for each of the plurality of input/output lines and the fault data; and
wherein the fault determining component is operable to output a fault signal based on the comparison values.

20. The apparatus of claim 18 , wherein:
the fault data includes one of an open circuit, a short circuit, a damaged touch sensor, and an indication of overheating.

Assignees

• Texas Instruments Inc

Inventors

• Jun Zhang
• Ge Shen
• Cheng xu kang
• Yi Zhou
• Meng Hao
• Jun Ji Ru

Classifications

• H03K17/9622 Primary

  using a plurality of detectors, e.g. keyboard · CPC title

• H03K2017/9613

  using two electrodes per touch switch · CPC title

• H03K2217/96066

  Thumbwheel, potentiometer, scrollbar or slider simulation by touch switch · CPC title