System and method for activating an electronic device using two or more sensors

1. An activation circuit for an electronic device, comprising:

a first heat sensor located on the electronic device in a first location where a user of the electronic device is expected to handle the electronic device;

a second heat sensor located on the electronic device in a second location where the user is not expected to handle the electronic device; and

an activation circuit to activate a component in the electronic device when the electronic device is in

a first environment that is room temperature and a difference in readings between the first heat sensor and the second heat sensor exceeds a first threshold to activate the electronic device at room temperature;

and the activation circuit further conditionally adjusts readings from the second heat sensor to adjusted readings and activates the component when

the electronic device is in a second environment having a second environment temperature reading that is less than room temperature whereby the second environment temperature reading is adjusted to a first adjusted reading, and the difference in readings between the first heat sensor and the first adjusted reading from the second heat sensor exceeds a second threshold to activate the electronic device at the temperature, the second threshold being different than the first threshold; and

the electronic device is in a third environment having a third environment temperature reading that is more than room temperature whereby the third environment temperature reading is adjusted to a second adjusted reading and the difference in readings between the first heat sensor and the second adjusted reading from the second heat sensor exceeds a third threshold to activate the electronic device at the temperature, the third threshold also being different than the first threshold.

2. The activation circuit as claimed in claim 1 , wherein the activation circuit evaluates the readings between the first and second heat sensors in a plurality of different temperatures away from room temperature.

3. The activation circuit as claimed in claim 1 , further comprising:

a third heat sensor located on the electronic device in a third location where the user is expected to handle the electronic device; and

a fourth heat sensor located on the electronic device in a fourth location that is also isolated from effects of the user,

wherein the activation circuit further activates the component when a difference in readings between the third and fourth heat sensors exceeds a fourth threshold.

4. The activation circuit as claimed in claim 3 , wherein:

the activation circuit further activates the component when differences in readings between the third and second heat sensors and from the first and fourth heat sensors-exceed a fifth threshold.

5. The activation circuit as claimed in claim 3 , wherein the activation circuit sequentially evaluates the difference in readings from the first and second heat sensors and then the difference in readings between the third and fourth heat sensors to determine whether to activate the component.

6. The activation circuit as claimed in claim 3 , wherein the activation circuit evaluates in combination the difference in readings between the first and second heat sensors and then the difference in readings between the third and fourth heat sensors to determine when to activate the component.

7. The activation circuit as claimed in claim 3 , further comprising:

a fifth heat sensor located on the electronic device in a fifth location that is also isolated from effects of the user,

wherein the activation circuit further utilizes readings from the fifth heat sensor to determine when to activate the component.

8. The activation circuit as claimed in claim 1 , wherein an output of the activation circuit is connected to an interrupt input line of a processor in the electronic device.

9. The activation circuit as claimed in claim 1 , wherein the activation circuit utilizes readings from the second heat sensor as a baseline condition to determine when to activate the component.

10. The activation circuit as claimed in claim 3 , wherein the activation circuit utilizes data from the second and fourth heat sensors as a baseline conditions to determine when to activate the component.

11. A method for activating a component in an electronic device, comprising:

monitoring readings from a first heat sensor located on the electronic device in a first location where a user of the electronic device is expected to handle the electronic device;

monitoring readings from a second heat sensor located on the electronic device in a second location where the user is not expected to handle the electronic device;

activating a component in the electronic device when the electronic device is in a first environment that is room temperature and a difference in readings between the first heat sensor and the second heat sensor exceeds a first threshold to activate the electronic device at room temperature; and

conditionally adjusting readings from the second heat sensor to adjusted readings and activating the component when

the electronic device is in a second environment having a second environment temperature reading that is less than room temperature whereby the second environment temperature reading is adjusted to a first adjusted reading, and the difference in readings between the first heat sensor and the first adjusted reading from the second heat sensor exceeds a second threshold to activate the electronic device at the temperature, the second threshold being different than the first threshold; and

the electronic device is in a third environment having a third environment temperature reading that is more than room temperature whereby the third environment temperature reading is adjusted to a second adjusted reading, and the difference in readings between the first heat sensor and the second adjusted reading from the second heat sensor exceeds a third threshold to activate the electronic device at the temperature, the third threshold also being different than the first threshold.

12. The method for activating a component as claimed in claim 11 , further comprising:

monitoring readings from a third heat sensor located on the electronic device in a third location where a user of the electronic device is expected to handle the electronic device; and

activating the component based on readings from the third heat sensor.

13. The activation circuit as claimed in claim 1 , further comprising:

a light detector,

wherein the activation circuit further utilizes readings from the light detector to determine when to activate the component.

14. The activation circuit as claimed in claim 1 , further comprising:

a motion sensor,

wherein the activation circuit further utilizes readings from the motion sensor to determine when to activate the component.

15. The method for activating a component as claimed in claim 11 , further comprising:

also utilizing reading from a light detector on the electronic device to determine when to activate the component.

16. The method for activating a component as claimed in claim 11 , further comprising:

also utilizing reading from a motion sensor on the electronic device to determine when to activate the component.

17. The method for activating a component as claimed in claim 11 , further comprising:

adjusting readings from the first heat sensor and activating the component when the user is wearing a glove and the difference in readings between a first adjusted reading of the first heat sensor and a reading from the second heat sensor exceeds a fourth threshold to activate the electronic device, the fourth threshold being smaller than the first threshold.

18. The activation circuit as claimed in claim 1 , wherein the activation circuit further adjusts readings from the first heat sensor and activates the component when

the user is wearing a glove and the difference readings between a first adjusted reading from the first heat sensor and a reading from the second heat sensor exceeds a fourth threshold to activate the electronic device, the fourth threshold being smaller than the first threshold.