Apparatus and method for detecting multiple buttons with one pin

• US 20070296709A1
• Filed: 06/27/2006
• Published: 12/27/2007
• Est. Priority Date: 06/27/2006
• Status: Active Grant

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: GuangHai, Li
• Granted Patent: US 8,068,097 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/0227 Cooperation and interconnection of the input arrangement with other functional units of a computer G06F3/023 - G06F3/037 take precedence
• CPC Class Codes: G06F 3/023 Arrangements for converting discrete items of information into a coded form, e.g. arrangements for interpreting keyboard generated codes as alphanumeric codes, operand codes or instruction codes
• 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
• 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

Abstract

An apparatus and method for distinguishing a particular button operation from among multiple button operations on a sensing device having multiple sensor elements that are electrically coupled together. The apparatus may include a sensing device having a first sensor element and a second element that are electrically coupled to detect a presence of a conductive object on the sensing device. The method may include detecting a presence of a conductive object on a sensing device having multiple sensor elements that are electrically coupled, each sensor element corresponding to a button operation, and distinguishing between the multiple button operations.

Claims

1. A method, comprising:

detecting a presence of a conductive object on a sensing device having a plurality of sensor elements that are electrically coupled, wherein the plurality of sensor elements correspond to a plurality of button operations; and

distinguishing a particular button operation from among the plurality of button operations.

2. The method of claim 1, wherein distinguishing the particular button operation comprises recognizing two or more button operations performed by the conductive object on the sensing device using one pin of a processing device.

3. The method of claim 1, wherein the plurality of sensor elements comprise different sensitivities.

4. The method of claim 1, wherein the plurality of sensor elements comprise different surface areas.

5. The method of claim 1, wherein distinguishing the particular button operation comprises:

recognizing a first button operation of the plurality of button operations when the presence of the conductive object is detected on a first sensor element of the plurality of sensor elements of the sensing device, wherein the presence of the conductive object is detected on the first sensor element when a measurement of the presence of the conductive object is greater than a first sensitivity threshold; and

recognizing a second button operation of the plurality of button operations when the presence of the conductive object is detected on a second sensor element of the plurality of sensor elements of the sensing device, wherein the presence of the conductive object is detected on the first sensor element when a measurement of the presence of the conductive object is less than the first sensitivity threshold and greater than a second sensitivity threshold.

6. The method of claim 5, wherein the first and second sensitivity thresholds are greater than a presence threshold, wherein the presence threshold is configured to indicate the detected presence of the conductive object.

7. The method of claim 1, wherein distinguishing the particular button operation comprises:

determining a capacitance of the conductive object on the sensing device;

detecting the presence of the conductive object on the first sensor element when the capacitance is greater than a first sensitivity threshold; and

detecting the presence of the conductive object on the second sensor element when the capacitance is less than the first sensitivity threshold and greater than a second sensitivity threshold.

8. The method of claim 7, further comprising:

recognizing a first button operation of the plurality of button operations when the presence of the conductive object is detected on the first sensor element of the sensing device; and

recognizing a second button operation of the plurality of button operations when the presence of the conductive object is detected on the second sensor element of the sensing device.

9. An apparatus, comprising:

a sensing device having a first sensor element and a second element that are electrically coupled to detect a presence of a conductive object on the sensing device, wherein the first sensor element corresponds to a first button operation and the second sensor element corresponds to a second button operation; and

a processing device coupled to the sensing device to distinguish a particular button operation from among the first and second button operations.

10. The apparatus of claim 9, wherein the first sensor element comprises a first surface area and the second sensor element comprises a second surface area, and wherein the first surface area is greater than the second surface area.

11. The apparatus of claim 9, wherein the first sensor element comprises a first sensitivity and the second sensor element comprises a second sensitivity, wherein the first sensitivity is greater than the second sensitivity, and wherein the processing device is configured to distinguish the particular button operation based on the first sensitivity of the first sensor element and the second sensitivity of the second sensor element.

12. The apparatus of claim 9, wherein the first and second sensor elements are electrically coupled.

13. The apparatus of claim 9, wherein the first and second sensor elements are coupled to the processing device using one pin.

14. The apparatus of claim 9, wherein the processing device is configured to recognize the first button operation when the presence of the conductive object is detected on the first sensor element of the sensing device, and to recognize the second button operation when the presence of the conductive object is detected on the second sensor element of the sensing device.

15. The apparatus of claim 9, wherein the processing device is configured to determine a capacitance of the conductive object on the sensing device.

16. The apparatus of claim 15, wherein the first button operation is recognized when the capacitance is greater than a first sensitivity threshold, and wherein the second button operation is recognized when the capacitance is less than the first sensitivity threshold and greater than a second sensitivity threshold.

17. The apparatus of claim 16, wherein the first and second sensitivity thresholds are greater than a presence threshold, wherein the presence threshold is configured to indicate the detected presence of the conductive object.

18. An apparatus, comprising:

a sensing device having a plurality of sensor elements that are electrically coupled, wherein the plurality of sensor elements correspond to a plurality of button operations; and

means for distinguishing a particular button operation, performed by a conductive object on the sensing device, from among the plurality of button operations.

19. The apparatus of claim 18, wherein means for distinguishing the particular button operation comprises means for distinguishing the particular button operation from among the plurality of button operations using one pin.

20. The apparatus of claim 18, further comprising means for detecting a presence of the conductive object on the sensing device.

21. The apparatus of claim 18, further comprising:

means for determining a capacitance of the conductive object on the sensing device; and

means for detecting the presence of the conductive object on a particular sensor element among the plurality of sensor elements based on sensitivity ranges of the plurality of sensor elements.

22. An apparatus, comprising:

a sensing device having a plurality of sensor elements that are electrically coupled to detect a presence of a conductive object on the sensing device, wherein the plurality of sensor elements correspond to a plurality of button operations;

a keyboard coupled to the sensing device, wherein the keyboard comprises a plurality of keys that correspond to the plurality of sensor elements; and

a processing device coupled to the sensing device to distinguish a particular button operation from among the plurality of button operations when a particular key of the plurality of keys of the keyboard is pressed.

23. The apparatus of claim 22, wherein the sensing device comprises:

a pad layer comprising conductive material that corresponds to the plurality of keys and the plurality of sensor elements, wherein the conductive material of the particular key is detected on the sensing device when pressed;

a routing layer comprising the plurality of sensor elements, wherein the routing layer is coupled to the processing device; and

an insulating layer coupled to electrically isolate the pad layer and the routing layer.

24. The apparatus of claim 23, further comprising a plastic film coupled between the plurality of keys and the pad layer of the sensing device.