Capacitive panel scanning with reduced number of sensing circuits

Patent metadata

Field	Value
Publication number	US-11320946-B2
Application number	US-201113247779-A
Country	US
Kind code	B2
Filing date	Sep 28, 2011
Priority date	Apr 19, 2011
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Embodiments described herein provide capacitive sensor devices and methods for operating capacitive sensor devices. A first number of electrodes on the capacitive sensor array is activated. A signal is received from each of the first number of electrodes with a second number of receiver circuits on a controller associated with the capacitive sensor array. The first number is greater than the second number. It is determined if an object is proximate the capacitive sensor array based on the signals received from the first number of electrodes.

First claim

What is claimed is:

1. A method for operating a capacitive sensor array comprising:
receiving a plurality of signals from each of a first number of electrodes with a second number of receiver circuits on a controller associated with the capacitive sensor array,
wherein the first number is greater than the second number, and wherein the received plurality of signals on the second number of receiver circuits is an algebraic sum of signals from at least two of the first number of electrodes; and
determining if an object is proximate the capacitive sensor array based on the signals received from the first number of electrodes,
wherein the capacitive sensor array comprises a plurality of transmitter electrodes and a plurality of receiver electrodes,
wherein the plurality of transmitter electrodes are separate and distinct from the plurality of receiver electrodes,
wherein the determining if the object is proximate the capacitive sensor array comprises adjusting the polarity of at least some of the signals received from the first number of receiver electrodes during one of the scanning cycles

wherein the polarity of the signal received from each of the first number of receiver electrodes is adjusted.

2. The method of claim 1 , wherein the determining if the object is proximate the capacitive sensor array comprises deconvoluting the signals received from the first number of receiver electrodes.

3. The method of claim 1 , wherein the first number of receiver electrodes comprises all of the plurality of receiver electrodes.

4. The method of claim 1 , wherein the determining if the object is proximate the capacitive sensor array further comprises scanning the signals received from the first number of receiver electrodes in a plurality of scanning cycles.

5. The method of claim 1 , wherein the first number of electrodes comprises a plurality of groups of receiver electrodes, and wherein during each of the scanning cycles, the polarity of the signals received from one of the groups of receiver electrodes is adjusted.

6. The method of claim 1 , wherein the determining if the object is proximate the capacitive sensor array comprises determining if the object is in contact with the capacitive sensor array.

7. The method of claim 6 , wherein the first number of receiver electrodes comprises only a portion of the plurality of receiver electrodes, and wherein the plurality of receiver electrodes comprises a plurality of groups of receiver electrodes, the determining if the object is within the predetermined proximity of the capacitive sensor array further comprises scanning the signals received from the first number of receiver electrodes in a plurality of scanning cycles, and wherein during each of the scanning cycles one of the groups of receiver electrodes is deactivated.

8. A capacitive sensor device comprising:
a capacitive sensor array comprising a plurality of transmitter electrodes and a plurality of receiver electrodes perpendicular to the transmitter electrodes and wherein the plurality of transmitter electrodes are separate and distinct from the plurality of receiver electrodes,
wherein a plurality of capacitive sensors is formed at intersections of each of the plurality of transmitter electrodes and receiver electrodes; and
a controller coupled to the capacitive sensor array and comprising a first number of receiver channels, the controller being configured to:
activate a second number of the plurality of receiver electrodes on the capacitive sensor array, wherein the second number is greater than the first number;

receive a plurality of signals signal from each of the second number of receiver electrodes with the first number of receiver channels,
wherein the received signal on the first number of receiver circuits is an algebraic sum of signals from at least two of the second number of receiver electrodes; and
determine if an object is proximate the capacitive sensor array based on the signals received from the second number of the plurality of receiver electrodes,
wherein the determining if the object is proximate the capacitive sensor array comprises adjusting the polarity of at least some of the signals received from the second number of the plurality of receiver electrodes.

9. The capacitive sensor device of claim 8 , wherein the determining if an object is proximate the capacitive sensor array comprises deconvoluting the signals received from the second number of the plurality of receiver electrodes.

10. The capacitive sensor device of claim 8 , wherein the determining if the object is proximate the capacitive sensor array further comprises scanning the signals received from the second number of the plurality of receiver electrodes in a plurality of scanning cycles.

11. A method for operating a capacitive sensor array comprising:
activating a first number of electrodes on the capacitive sensor array, wherein the capacitive sensor array comprises a plurality of transmitter electrodes and a plurality of receiver electrodes, the first number of electrodes comprises all of the receiver electrodes, and wherein the plurality of transmitter electrodes are separate and distinct from the plurality of receiver electrodes;
receiving a plurality of signals signal from each of the first number of receiver electrodes with a second number of receiver channels on a controller associated with the capacitive sensor array, wherein the first number is greater than the second number, and wherein the received signal on the second number of receiver circuits is an algebraic sum of signals from at least two of the first number of receiver electrodes; and
determining if an object is proximate the capacitive sensor array based on the signals received from the first number of receiver electrodes,
wherein the determining if the object is within a predetermined proximity of the capacitive sensor array comprises adjusting the polarity of at least some of the signals received from the first number of receiver electrodes, and
wherein the polarity of the signal received from each of the plurality of receiver electrodes is adjusted during one of the scanning cycles.

12. The method of claim 11 , wherein the determining if an object is proximate the capacitive sensor array further comprises deconvoluting the signals received from the first number of receiver electrodes.

13. The method of claim 12 , wherein the determining if the object is proximate the capacitive sensor array further comprises scanning the signals received from the first number of receiver electrodes in a plurality of scanning cycles.

14. The method of claim 13 , wherein the plurality of receiver electrodes comprises a plurality of groups of receiver electrodes, and wherein during each of the scanning cycles, the polarity of the signals received from one of the groups of receiver electrodes is adjusted.

Assignees

• Kremin Viktor
• Ogirko Roman
• Cypress Semiconductor Corp

Inventors

• Kremin Viktor
• Ogirko Roman

Classifications

• G06F3/0446 Primary

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title

• G06F3/04166

  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 title