Power management for input device
An input device for a computer system includes a force sensor, disposed in a dedicated sensing region, a touch sensor, disposed in the dedicated sensing region, and a processing system. The processing system detects a presence of a force applied in the dedicated sensing region, using the force sensor, and based on the detection of the presence of the force, changes a state of the input device from an idle state to an active state. When in the idle state, touch sensing by the input device is inactive. When in the active state, the touch sensing by the input device is active.
1. An input device for a computer system, the input device comprising:
a force sensor, disposed in a dedicated sensing region;
a touch sensor, disposed in the dedicated sensing region,
wherein the dedicated sensing region is in absence of a display; and
a processing system that:
detects a presence of a force applied in the dedicated sensing region, using the force sensor,
based on the detection of the presence of the force, changes a state of the input device from an idle state to an active state,
wherein when in the idle state, touch sensing by the input device is inactive while force sensing is active,
wherein when in the active state, the touch sensing by the input device is active.
2. The input device according to claim 1 , wherein the touch sensing comprises:
determining a location of a touch in the dedicated sensing region by the touch sensor, and
based on the detection, reporting the location to a host system of the computer system.
3. The input device according to claim 1 , wherein the processing system further:
detects an absence of touch in the dedicated sensing region for at least a predetermined time, and
based on the detection of the absence of touch, changes the state of the input device from the active state to the idle state.
4. The input device according to claim 3 ,
wherein the processing system comprises a touch controller, and
wherein changing the state of the input device from the active state to the idle state comprises:
stopping driving sensor electrodes of the touch sensor, and
stopping scanning the sensor electrodes of the touch sensor.
5. The input device according to claim 4 ,
wherein changing the state of the input device from the active state to the idle state further comprises:
continuing driving at least a first of a plurality of sensor electrodes of the force sensor, and
stopping driving at least a second of the plurality of sensor electrodes of the force sensor.
6. The input device according to claim 3 ,
wherein the processing system comprises a touch controller and a force controller, and
wherein changing the state of the input device from the active state to the idle state comprises:
powering down the touch controller, and
continuing operating the force controller.
7. The input device according to claim 1 , wherein the processing system:
based on the detection of the presence of the force,
changes a state of the computer system from a sleep state to an active state.
8. The input device according to claim 1 , wherein:
the force sensor comprises at least one selected from a group consisting of a capacitive force sensor, a resistive force sensor, an elastive force sensor, an inductive force sensor, a piezoelectric force sensor, and a strain sensor.
9. The input device according to claim 1 , wherein:
the touch sensor comprises at least one selected from a group consisting of a capacitive touch sensor, a resistive touch sensor, and a piezoelectric touch sensor.
10. A method of operating an input device for a computer system comprises:
detecting a presence of a force applied in a dedicated sensing region of the input device, using a force sensor disposed in the dedicated sensing region, wherein the dedicated sensing region is in absence of a display;
based on the detection of the presence of the force, changing a state of the input device from an idle state to an active state,
wherein when in the idle state, touch sensing by the input device is inactive while force sensing is active,
wherein when in the active state, the touch sensing by the input device is active.
11. The method according to claim 10 , wherein the touch sensing comprises:
determining a location of a touch in the dedicated sensing region by the touch sensor, and
based on the detection, reporting the location to a host system of the computer system.
12. The method according to claim 10 , wherein operating the input device further comprises:
detecting an absence of touch in the dedicated sensing region, for at least a predetermined time, and
based on the detection of the absence of touch, changing the state of the input device from the active state to the idle state.
13. The method according to claim 10 , wherein operating the input device further comprises:
based on the detection of the presence of the force, changing a state of the computer system from a sleep state to an active state.
14. The method according to claim 10 , wherein:
the force sensor comprises at least one selected from a group consisting of a capacitive force sensor, a resistive force sensor, an elastive force sensor, an inductive force sensor, a piezoelectric force sensor, and a strain sensor.
15. The method according to claim 10 , wherein:
the touch sensor comprises at least one selected from a group consisting of a capacitive touch sensor, a resistive touch sensor, and a piezoelectric touch sensor.
16. A computer system comprising:
a host system; and
an input device communicatively interfacing with the host system, the input device comprising:
a force sensor, disposed in a dedicated sensing region;
a touch sensor, disposed in the dedicated sensing region,
wherein the dedicated sensing region is in absence of a display; and
a processing system that:
detects a presence of a force applied in the dedicated sensing region, using the force sensor,
based on the detection of the presence of the force, changes a state of the input device from an idle state to an active state,
wherein when in the idle state, touch sensing by the input device is inactive while force sensing is active,
wherein when in the active state, the touch sensing by the input device is active.
17. The computer system according to claim 16 , wherein the processing system further:
detects an absence of touch in the dedicated sensing region for at least a predetermined time, and
based on the detection of the absence of touch, changes the state of the input device from the active state to the idle state.
18. The computer system according to claim 17 ,
wherein the processing system comprises a touch controller, and
wherein changing the state of the input device from the active state to the idle state comprises:
stopping driving sensor electrodes of the touch sensor, and
stopping scanning the sensor electrodes of the touch sensor.
19. The computer system according to claim 18 ,
wherein changing the state of the input device from the active state to the idle state further comprises:
continuing driving at least a first of a plurality of sensor electrodes of the force sensor, and
stopping driving at least a second of the plurality of sensor electrodes of the force sensor.
20. The computer system according to claim 17 ,
wherein the processing system comprises a touch controller and a force controller, and
wherein changing the state of the input device from the active state to the idle state comprises:
powering down the touch controller, and
continuing operating the force controller.