Electronic device, power control method and storage medium storing program thereof

• US 9,915,997 B2
• Filed: 03/10/2014
• Issued: 03/13/2018
• Est. Priority Date: 03/18/2013
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Asano, Kohei
• Primary Examiner(s): LEE, THOMAS C
• Assistant Examiner(s): Rahman, Mohammad A
• Application Number:
  US14/203,148
• Publication Number:
  US 20140281631A1
• Time in Patent Office: 1,464 Days
• CPC Class Codes: G06F 1/3231 Monitoring the presence, absence or movement of users
• CPC Class Codes: G06F 1/325 Power saving in peripheral device
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

In an electronic device, a first sensor detects a detection target on a first region. A second sensor detects a detection target on a second region. A third sensor detects a detection target on a third region. A power control unit turns on the second sensor in a case where the first sensor detects the detection target on the first region. The power control unit turns on the third sensor and turns off the first sensor in a case where the second sensor detects the detection target on the second region.

Claims

1. An electronic device comprising:

a first sensor;

a second sensor;

a third sensor; and

a controller which includes one or more processors,

wherein;

(i) the second sensor is turned on based on a detection result of the first sensor,

(ii) the third sensor is turned on based on a detection result of the second sensor, and

(iii) the first sensor is turned off based on a detection result of the third sensor, and

wherein the controller is returned to a first power mode from a second power mode, in which power consumption is lower than power consumption of the first power mode, based on a detection result of the second sensor.

2. The device according to claim 1, further comprising:

a power supply configured to output power to the controller,

wherein the power supply outputs power to the controller based on the detection result of the second sensor.

3. The device according to claim 1, wherein the second sensor is turned off after the controller is returned to the first power mode from the second power mode.

4. The device according to claim 3, wherein the third sensor is constructed to output a reset signal to the controller;

wherein the third sensor stops outputting the reset signal based on the detection result of the third sensor.

5. The device according to claim 1, further comprising:

a switch which is connected to the second sensor and which is able to be turned on or off,

wherein the switch is turned on based on the detection result of the first sensor.

7. The device according to claim 1, further comprising:

a switch which is connected to the third sensor and which is able to be turned on or off,

wherein the switch is turned on based on the detection result of the second sensor.

8. The device according to claim 1, wherein the first sensor has a first detection region, the second sensor has a second detection region which is smaller than the first detection region, and the third sensor has a third detection region which is smaller than the second detection region.

9. The device according to claim 2, wherein the controller further includes a ROM and a RAM,

wherein, in a case where the power is outputted from the power supply, the one or more processors read data from the ROM, load the read data into the RAM, and then stand by in a reset state.

10. The device according to claim 9, wherein a reset state is cancelled based on the detection result of the third sensor.

11. The device according to claim 1, wherein at least one of the first sensor, the second sensor, and the third sensor is a pyroelectric sensor.

12. The device according to claim 1, wherein at least one of the first sensor, the second sensor, and the third sensor outputs and receives infrared light.

6. A power control method for an electronic device that includes a first sensor, a second sensor, a third sensor, and a controller that includes one or more processors, the method, performed by the controller, comprising:

turning on the second sensor based on a detection result of the first sensor;

turning on a third sensor based on a detection result of the second sensor;

turning off the first sensor based on the detection result of the third sensor; and

wherein the controller is returned to a first power mode from a second power mode, in which power consumption is lower than power consumption of the first power mode, based on the detection result of the second sensor.

13. The method according to claim 6, further comprising:

outputting power from a power supply to the controller based on the detection result of the second sensor.

14. The method according to claim 6, further comprising:

turning off the second sensor when the controller is returned to the first power mode from the second power mode.

15. The method according to claim 14, further comprising:

outputting a reset signal from the third sensor to the controller,

wherein the third sensor stops outputting the reset signal based on the detection result of the third sensor.

16. The method according to claim 6, further comprising:

turning on a switch connected to the second sensor based on the detection result of the first sensor.

17. The method according to claim 6, further comprising:

turning on a switch connected to the third sensor based on the detection result of the second sensor.

18. The method according to claim 6, wherein the first sensor has a first detection region, the second sensor has a second detection region which is smaller than the first detection region, and the third sensor has a third detection region which is smaller than the second detection region.

19. The method according to claim 13, further comprising:

reading data from ROM included in the controller;

loading the read data from the ROM into RAM included in the controller; and

causing the controller to stand by in a reset state.