Interleaving sense elements of a capacitive-sense array

• US 8,872,526 B1
• Filed: 12/05/2013
• Issued: 10/28/2014
• Est. Priority Date: 09/10/2013
• Status: Active Grant

• Current Assignee: Monterey Research, LLC (Vector Capital Corporation)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Hoshtanar, Oleksandr, Kravets, Igor
• Primary Examiner(s): Hollington, Jermele M
• Assistant Examiner(s): CURTIS, SEAN M
• Application Number:
  US14/098,057
• Time in Patent Office: 327 Days
• Field of Search: 324/658
• US Class Current: 324/658
• CPC Class Codes: G01D 5/24 by varying capacitance
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: G06F 3/0442 using active external devices, e.g. active pens, for transmitting changes in electrical potential to be received by the digitiser
• 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: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard

Abstract

Apparatuses and methods of sense arrays with interleaving sense elements are described. One capacitive-sense array includes a first electrode and a second electrode disposed adjacent to the first electrode in a first axis. The capacitive-sense array comprises a sensor pitch in the first axis. The first electrode includes a first sense element including a first shape and a first interleaving sense element that interleaves with a first portion and a second portion of the second electrode to extend a first dimension of the first electrode to be greater than the sensor pitch in the first axis. The second electrode includes a second sense element including the first shape and a second interleaving sense element that interleaves with a first portion and a second portion of the first electrode to extend a second dimension of the second electrode to be greater than the sensor pitch in the first axis.

Claims

1. A capacitive-sense array comprising:

a first electrode disposed along a first axis; and

a second electrode disposed along the first axis, the second electrode disposed adjacent to the first electrode, wherein the capacitive-sense array comprises a sensor pitch in the first axis,

wherein the first electrode comprises;

a first sense element comprising a first shape; and

a first interleaving sense element, wherein the first interleaving sense element is disposed to interleave with an extended portion and a base portion of the second electrode to extend a first dimension of the first electrode to be greater than the sensor pitch in the first axis,

wherein the second electrode comprises;

a second sense element comprising the first shape; and

a second interleaving sense element, wherein the second interleaving sense element is disposed to interleave with an extended portion and a base portion of the first electrode to extend a second dimension of the second electrode to be greater than the sensor pitch in the first axis,

wherein an area defined by a maximum width of the first electrode and a maximum of height of the first electrode is at least two times a product of the first dimension and the second dimension.

2. The capacitive-sense array of claim 1, wherein the first sense element and the first interleaving sense element comprise a same surface area.

3. The capacitive-sense array of claim 1, wherein the first interleaving sense element comprises a connecting line, wherein the extended portion of the first electrode is coupled to the base portion of the first electrode by the connecting line, and wherein the extended portion of the first electrode is disposed to interleave with the extended portion and the base portion of the second electrode.

4. The capacitive-sense array of claim 3, wherein the first shape is a solid diamond, and wherein the extended portion comprises a smaller diamond shape than the first shape.

5. The capacitive-sense array of claim 1, wherein the first electrode and the second electrode are part of a first set of electrodes along the first axis, and wherein the capacitive-sense array further comprises a second set of electrodes disposed along a second axis, wherein at least one of the second set of electrodes comprises:

a third sense element comprising a third shape; and

a third interleaving sense element, wherein the third interleaving sense element interleaves with an extended portion and a base portion of another one of the second set of electrodes to extend a third dimension of the at least one of the second set of electrodes to be greater than a second sensor pitch of the capacitive-sense array in the second axis.

6. The capacitive-sense array of claim 5, wherein the first set of electrodes intersect the second set of electrodes to form a plurality of unit cells each corresponding to an intersection of a pair of electrodes comprising one electrode from the first set and one electrode from the second set.

7. The capacitive-sense array of claim 5, wherein the first set of electrodes comprise a modified double solid diamond (DSD) pattern, wherein the modified DSD pattern comprises:

a first line of interconnected electrodes comprising first diamond shape elements and first interleaving elements that interleave with portions of the second electrode on a first side;

a second line of interconnected electrodes comprising second diamond shape elements and second interleaving elements that interleave with portions of a third electrode on a second side.

8. The capacitive-sense array of claim 1, wherein the first electrode and the second electrode are part of a first set of electrodes in the first axis, and wherein the capacitive-sense array further comprises a second set of electrodes disposed in a second axis, and wherein the first set of electrodes and the second set of electrodes are disposed in a single layer.

9. The capacitive-sense array of claim 8, wherein the first set of electrodes and the second set of electrodes comprise a swirl region used for interleaving in the single layer.

10. The capacitive-sense array of claim 9, wherein the swirl region comprise at least one of a square swirl region, a triangle swirl region, or a sector swirl region.

11. The capacitive-sense array of claim 1, wherein the first dimension is two or more times greater than the sensor pitch in the first axis.

12. A method comprising:

applying a transmit (TX) signal on a first electrode of a first set of electrodes of a capacitive-sense array comprising a sensor pitch along a first axis, the first set of electrodes disposed along the first axis;

measuring a receive (RX) signal on a second electrode of a second set of electrodes, wherein the second set of electrodes is disposed along a second axis, wherein the first set of electrodes intersect the second set of electrodes to form a plurality of unit cells each corresponding to an intersection of a pair of electrodes comprising one electrode from the first set and one electrode from the second set, wherein the second electrode comprises;

a first sense element comprising a first shape; and

a first interleaving sense element, wherein the first interleaving sense element is disposed to interleave with an extended portion and a base portion of a third electrode of the second set of electrodes, wherein the first interleaving sense element extends a first dimension of the second electrode to be greater than the sensor pitch in the first axis, wherein the third electrode comprises a second sense element comprising the first shape and a second interleaving sense element disposed to interleave with an extended portion and a base portion of the second electrode to extend a second dimension of the third electrode to be greater than the sensor pitch in the first axis; and

converting the measured RX signal into a first digital value, wherein the first digital value represents a first capacitance at the intersection between the first electrode and the second electrode.

13. The method of claim 12, further comprising:

measuring a second RX signal on the third electrode of the second set of electrodes; and

converting the second RX signal into a second digital value, wherein the second digital value represents a second capacitance at the intersection between the first electrode and the third electrode.

14. The method of claim 13, further comprising:

applying the TX signal on a fourth electrode of the first set of electrodes;

measuring a third RX signal on the second electrode;

converting the third RX signal into a third digital value, wherein the third digital value represents a third capacitance at the intersection between the fourth electrode and the second electrode;

measuring a fourth RX signal on the third electrode; and

converting the fourth RX signal into a fourth digital value, wherein the fourth digital value represents a fourth capacitance at the intersection between the fourth electrode and the third electrode.

15. An apparatus comprising:

a capacitive-sense array of a plurality of electrodes, wherein the plurality of electrodes comprises;

a first set of electrodes disposed along a first axis; and

a second set of electrodes disposed along a second axis,

wherein the first set of electrodes intersect the second set of electrodes to form a plurality of unit cells each corresponding to an intersection of a pair of electrodes comprising one electrode from the first set and one electrode from the second set,

wherein a first electrode of the first set of electrodes comprises a first sense element comprising a first shape and a first interleaving sense element,

wherein the first interleaving sense element interleaves with an extended portion and a base portion of a second electrode of the second set of electrodes,

wherein the first interleaving sense element extends a first dimension of the first electrode to be greater than the sensor pitch in the first axis,

wherein the first dimension is two times or greater than the sensor pitch; and

a processing device coupled to the capacitive-sense array, wherein the processing device is configured to measure signals from the capacitive sense-array to determine capacitance values for the plurality of unit cells.

16. The apparatus of claim 15, wherein the first sense element and the first interleaving sense element comprise a same surface area, and wherein the first interleaving sense element comprises a connecting line, wherein the extended portion of the first electrode of the first set of electrodes is coupled to the base portion of the first electrode of the first set of electrodes via the connecting line.

17. The apparatus of claim 15, wherein the second electrode comprises:

a second sense element comprising the first shape; and

a second interleaving sense element, wherein the second interleaving sense element interleaves with an extended portion and a base portion of the first interleaving sense element to extend a second dimension of the second electrode to be greater than the sensor pitch in the first axis, wherein the second dimension is two times or greater than the sensor pitch.

18. The apparatus of claim 17, wherein at least one of the second set of electrodes comprises:

a third sense element comprising a third shape; and

a third interleaving sense element, wherein the third interleaving sense element is disposed to interleave with an extended portion and a base portion of another one of the second set of electrodes to extend a third dimension of the at least one of the second set of electrodes to be greater than a sensor pitch of the capacitive-sense array in the second axis, wherein the third dimension is at least two times or greater than the sensor pitch in the second axis.

19. The apparatus of claim 17, wherein the first set of electrodes and the second set of electrodes are disposed in a single layer.