Battery operated device having power saving mode
A battery-powered electronic device comprises at least one functional circuit and a controller adapted to receive a signal representative of residual energy of a battery powering the device and to cut off operating power of the functional circuit if said residual energy is below a predetermined threshold. The controller is further adapted to detect whether a predetermined criterion is fulfilled or not, to cut off operating power of the functional circuit only if the predetermined criterion has been fulfilled for a given time interval, and to set the duration of the time interval depending on said residual energy.
1 . Battery-powered electronic device comprising at least one functional circuit and a controller adapted to receive a signal representative of residual energy of a battery powering the device and to cut off operating power of the functional circuit if said residual energy is below a predetermined threshold, characterized in that the controller is further adapted to detect whether a predetermined criterion is fulfilled or not, to cut off operating power of the functional circuit only if the predetermined criterion has been fulfilled for a given time interval, and to set the duration of the time interval depending on said residual energy, wherein one of the functional circuits is a user interface and the predetermined criterion being for the controller that the user interface was not manipulated by a user during said given time interval.
2 . The device of claim 1 , further comprising a battery monitor for providing said signal representative of the residual energy.
3 . The device of claim 1 , further comprising a battery compartment in which is provided a terminal for receiving said signal representative of the residual energy.
4 . The device of claim 1 , wherein there are at least two functional circuits, and the controller is adapted to cut off operating power of a first one of said functional circuits while maintaining operating power of a second one of said functional circuits.
5 . The device of claim 4 , wherein the first circuit comprises display illumination means.
6 . The device of claim 2 , wherein the controller is adapted to reduce the duration by a step when the residual energy decreases below a predetermined threshold.
7 . The device of claim 6 , comprising means for allowing a user to set the duration of the time interval to an initial value, the controller being adapted to set said duration to a second, smaller value when the residual energy decreases below said predetermined threshold.
8 . The device of claim 6 , wherein said threshold is additionally dependent on a respective operating mode of the device.
9 . The device of claim 7 , wherein the device is selected from the group comprising mobile telephones, portable media players and cameras.
10 . Battery-powered electronic device comprising at least one functional circuit and a controller adapted to receive a signal representative of residual energy of a battery powering the device and to cut off operating power of the functional circuit if said residual energy is below a predetermined threshold, wherein the controller is further adapted to detect whether a predetermined criterion is fulfilled or not, to cut off operating power of the functional circuit only if the predetermined criterion has been fulfilled for a given time interval, and to set the duration of the time interval depending on said residual energy, wherein one of the functional circuits is a means for detecting movement and the predetermined criterion being for the controller a detection of absence of movement during said given time interval, or wherein one of the functional circuits is a data communication circuit and the criterion for the controller being the absence of data communication from or to the device for said given time interval.
11 . The device of claim 10 , further comprising a battery monitor for providing said signal representative of the residual energy.
12 . The device of claim 10 , further comprising a battery compartment in which is provided a terminal for receiving said signal representative of the residual energy.
13 . The device of claim 10 , wherein there are at least two functional circuits, and the controller is adapted to cut off operating power of a first one of said functional circuits while maintaining operating power of a second one of said functional circuits.
14 . The device of claim 13 , wherein the first circuit comprises display illumination means.
15 . The device of claim 13 , wherein the controller is adapted to reduce the duration by a step when the residual energy decreases below a predetermined threshold.
16 . The device of claim 15 , comprising means for allowing a user to set the duration of the time interval to an initial value, the controller being adapted to set said duration to a second, smaller value when the residual energy decreases below said predetermined threshold.
17 . The device of claim 15 , wherein said threshold is additionally dependent on a respective operating mode of the device.
18 . The device of claim 10 , wherein the device is selected from the group comprising mobile telephones, portable media players and cameras.