Apparatus and method for controlling an electrical switch array

• US 20030206155A1
• Filed: 05/02/2002
• Published: 11/06/2003
• Est. Priority Date: 10/15/2001
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Mitchell, Michael Lane
• Granted Patent: US 6,869,011 B2
• Time in Patent Office: Days
• US Class Current: 345/168
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3271 Power saving in keyboard
• CPC Class Codes: H03M 11/20 Dynamic coding, i.e. by key scanning H03M11/26 takes precedence
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

An electrical switching apparatus configured for low power operation includes: (a) a plurality of switching devices arranged in a switching array permitting sensing of individual switching events by selected switching devices; (b) a switching control device coupled with the switching array that provides power to the switching array for sensing and for a first time interval after a first switching device is actuated. The control device identifies the first switching device during the first time interval and interrupts power to the switching array after the first time interval until the first switching device is deactuated. The control device provides power to the switching array for a second time interval after the first switching device is deactuated. The control device determines during the second time interval whether a second switching device other than the first switching device is actuated.

Claims

1. An electrical switching apparatus configured for low power operation;

the apparatus comprising;

(a) a plurality of switching devices;

said plurality of switching devices being arranged in a switching array permitting sensing of individual switching events by selected switching devices of said plurality of switching devices;

(b) a switching control device coupled with said switching array;

said control device providing power to said switching array for said sensing and for a first time interval after a first said switching device of said plurality of switching devices is actuated;

said control device identifying said first switching device during said first time interval;

said control device interrupting power to said switching array after said first time interval until said first switching device is deactuated;

said control device providing power to said switching array for a second time interval after said first switching device is deactuated;

said control device determining during said second time interval whether a second said switching device of said plurality of switching devices other than said first switching device is actuated.

2. An electrical switching apparatus configured for low power operation as recited in claim 1 wherein said control device responds to a second said switching device of said plurality of switching devices being actuated during said second time interval by identifying said second switching device during said second time interval;

said control device interrupting power to said switching array after said second time interval until said second switching device is deactuated.

3. An electrical switching apparatus configured for low power operation as recited in claim 1 wherein said control device responds to no second said switching device of said plurality of switching devices being actuated during said second time interval by restoring power to said switching array after said second time interval.

4. An electrical switching apparatus configured for low power operation as recited in claim 2 wherein said control device responds to no second said switching device of said plurality of switching devices being actuated during said second time interval by restoring power to said switching array after said second time interval.

5. A switching control apparatus for controlling an electrical keyswitch array including a plurality of keyswitches;

the apparatus comprising;

(a) a switching control device coupled with said keyswitch array;

said switching control device controlling application of electrical power to said keyswitch array; and

(b) a sensing device coupled with said keyswitch array;

said sensing device cooperating with said switching device to effect periodic sensing of respective keyswitches of said plurality of keyswitches;

said switching control device providing said electrical power to said keyswitch array for said sesnsing and during a first time interval after a first keyswitch of said plurality of keyswitches is actuated;

said sensing device identifying said first keyswitch during said first time interval;

said switching device interrupting power to said keyswitch array after said first time interval until said sensing device senses said first keyswitch is deactuated;

said switching device providing said electrical power to said keyswitch array for a second time interval after said first keyswitch is deactuated;

said sensing device sensing during said second time interval whether a second said keyswitch of said plurality of keyswitches other than said first keyswitch is actuated.

6. A switching control apparatus for controlling an electrical keyswitch array including a plurality of keyswitches as recited in claim 5 wherein said sensing device responds to a second said keyswitch of said plurality of keyswitches being actuated during said second time interval by identifying said second keyswitch during said second time interval;

said switching device responding to said second keyswitch being actuated during said second time interval by interrupting power to said keyswitch array after said second time interval until said second keyswitch is deactuated.

7. A switching control apparatus for controlling an electrical keyswitch array including a plurality of keyswitches as recited in claim 5 wherein said switching device responds to no second keyswitch of said plurality of keyswitches being actuated during said second time interval by restoring power to said keyswitch array after said second time interval.

8. A switching control apparatus for controlling an electrical keyswitch array including a plurality of keyswitches as recited in claim 6 wherein said switching device responds to no second keyswitch of said plurality of keyswitches being actuated during said second time interval by restoring power to said keyswitch array after said second time interval.

9. A method for operating an electrical switching apparatus;

said electrical switching apparatus including a plurality of switching devices arranged in a switching array;

said switching array being configured to permit sensing of individual switching events by selected switching devices of said plurality of switching devices;

the method comprising the steps of;

(a) detecting when a first switching device of said plurality of switching devices is actuated;

(b) providing power to said switching array for said sensing and for a first time interval after said first switching device is actuated;

(c) identifying said first switching device during said first time interval;

(d) interrupting power to said switching array after said first time interval until said first switching device is deactuated;

(e) providing power to said switching array for a second time interval after said first switching device is deactuated; and

(f) determining during said second time interval whether a second said switching device of said plurality of switching devices other than said first switching device is actuated.

10. A method for operating an electrical switching apparatus as recited in claim 9 wherein the method comprises the further steps of:

(g) when a second said switching device is actuated during said second time interval, identifying said second switching device during said second time interval; and

(h) interrupting power to said switching array after said second time interval until said second switching device is deactuated.

11. A method for operating an electrical switching apparatus as recited in claim 9 wherein the method comprises the further steps of:

(g) when no second said switching device is actuated during said second time interval, restoring power to said switching array after said second time interval.