POWER SAVING SYSTEM FOR A HANDHELD COMMUNICATION DEVICE HAVING A FULL ALPHABETIC KEYBOARD

1 . A method for reducing power consumption during periods of non-use by a handheld electronic device having a trackball navigation tool exposed at a face thereof, said method comprising effecting a power-saving mode by disabling a power-consuming sensor that detects motion of a ball of the trackball navigation tool when non-use of the device is determined and wherein said device comprises a keyboard having a plurality of keys with which alphabetic letters are associated, one letter per key.

2 . The method of claim 1 , wherein said determination of non-use of the device is based on a preselected period of time elapsing between sensor-detected movements of the ball of the trackball navigation tool.

3 . The method of claim 1 , wherein said determination of non-use of the device is based on user actuation of a preset key combination.

4 . The method of claim 3 , wherein said actuation of a preset key combination comprises depressing and holding the ball of the ball of the trackball navigation tool for longer than a preset time period.

5 . The method of claim 1 , wherein the power-consuming sensor is one of a plurality of power-consuming sensors, each of which is positioned adjacent the trackball navigation tool for determining increments of rotation of the ball of the tool about a particular axis of rotation.

6 . The method of claim 5 , wherein each of the power-consuming sensors is a hall effect sensor.

7 . The method of claim 5 , wherein the plurality of power-consuming sensors number four and are arranged at ninety degree intervals about the trackball navigation tool.

8 . The method of claim 1 , wherein disabling the power-consuming sensor is effected by removing power supplied thereto and thereby reducing power consumption by the device.

9 . The method of claim 1 , further comprising disabling a display screen of the handheld electronic device upon entering the power-saving mode and thereby reducing power consumption by the device.

10 . The method of claim 1 , further comprising disabling a display screen of the handheld electronic device upon entering the power-saving mode and before disabling the power-consuming sensor thereby instituting a display screen sleep mode which reduces power consumption by the device.

11 . The method of claim 10 , further comprising exiting the display screen sleep mode when motion of the ball of the trackball navigation tool is detected before disablement of the power-consuming sensor is effected.

12 . The method of claim 10 , wherein power consumption is stepwise reduced in degree with an initial amount of power-savings being experienced from the institution of the display screen sleep mode and an incremental increase in power-savings being experienced when the power-consuming sensor is disabled.

13 . The method of claim 1 , further comprising restoring the device to a use-mode in response to user actuation of a preset wakeup key combination.

14 . The method of claim 5 , wherein said plurality of power-consuming sensors produce x-direction signals and y-direction signals based on sensed movement of the ball of the trackball navigation tool and a processor analyzes the produced x-direction signals and y-direction signals and outputs a cursor control signal based thereupon.

15 . The method of claim 14 , wherein said each of the power-consuming sensors is a hall effect sensor.

16 . The method of claim 2 , wherein said device further comprises a radio transmitter capable of transmitting data to a communication network utilizing radio frequency signals and a radio receiver capable of receiving data from the communication network utilizing radio frequency signals.

17 . The method of claim 16 , wherein the data transmitted between said handheld communication device and the communication network supports voice and textual messaging.

18 . The method of claim 1 , wherein said alphabetic letters are configured in one of a QWERTY, QWERTZ, AZERTY, and Dvorak layout.

19 . A handheld electronic device, comprising:

a trackball navigation tool having a freely rotatable ball exposed for user manipulation at an exterior face of the device;

a power-consuming sensor capable of sensing movement of the ball of the trackball navigation tool indicative of the user's desire to effect corresponding cursor movement on a display screen of the device;

a processor programmed to reduce power consumption during periods of device non-use by instituting a power-saving mode that disables the sensor when non-use of the device is determined; and

a keyboard comprising a plurality of keys with which alphabetic letters are associated, one letter per key.

20 . The device of claim 19 , further comprising:

a keyboard suitable for accommodating textual input to the handheld electronic device located beneath a lighted display screen, said screen and said keyboard being located at a front face of said device; and

said trackball navigation tool being located essentially between the display and the keyboard.

21 . The device of claim 19 , wherein said determination of non-use of the device is based on a preselected period of time elapsing between sensor-detected movements of the ball of the trackball navigation tool.

22 . The device of claim 19 , wherein said determination of non-use of the device is based on user actuation of a preset key combination.

23 . The device of claim 22 , wherein said actuation of the preset key combination comprises depressing and holding the trackball navigation tool for longer than a preset time period.

24 . The device of claim 19 , wherein the sensor is one of a plurality of sensors, each of which is positioned adjacent the trackball navigation tool for determining increments of rotation of the ball of the tool about a particular axis of rotation.

25 . The device of claim 24 , wherein said each of the power-consuming sensors is a hall effect sensor.

26 . The device of claim 24 , wherein the plurality of power-consuming sensors number four and are arranged at ninety degree intervals about the trackball navigation tool.

27 . The device of claim 19 , wherein disabling the power-consuming sensor is effected by removing power supplied thereto and thereby reducing power consumption by the device.

28 . The device of claim 19 , further comprising disabling a display screen of the handheld electronic device upon entering the power-saving mode and thereby reducing power consumption by the device.

29 . The device of claim 19 , further comprising disabling said lighted display screen of the handheld electronic device upon entering the power-saving mode and before disabling the power-consuming sensor thereby instituting a display screen sleep mode which reduces power consumption by the device.

30 . The device of claim 29 , further comprising exiting the display screen sleep mode when motion of the ball of the trackball navigation tool is detected before disablement of the power-consuming sensor is effected.

31 . The device of claim 29 , wherein the power consumption is stepwise reduced in degree with an initial amount of power-savings being experienced from the institution of the display screen sleep mode and an incremental increase in power-savings being experienced when the power-consuming sensor is disabled.

32 . The device of claim 19 , further comprising restoring the device to a use-mode based on user actuation of a preset wakeup key combination.

33 . The device of claim 24 , wherein said plurality of the power-consuming sensors produce x-direction signals and y-direction signals based on sensed movement of the ball of the trackball navigation tool and a processor analyzes the produced x-direction signals and y-direction signals and outputs a cursor control signal based thereupon.

34 . The device of claim 33 , wherein said each of the power-consuming sensors is a hall effect sensor.

35 . The device of claim 19 , further comprising a radio transmitter capable of transmitting data to a communication network utilizing radio frequency signals and a radio receiver capable of receiving data from the communication network utilizing radio frequency signals.

36 . The device of claim 35 , wherein the data transmitted between said handheld communication device and the communication network supports voice and textual messaging.

37 . The device of claim 19 , wherein said alphabetic letters are configured in one of a QWERTY, QWERTZ, AZERTY, and Dvorak layout.