Adjustable cut-off voltage for mobile device battery

• US 20090045779A1
• Filed: 08/13/2007
• Published: 02/19/2009
• Est. Priority Date: 08/13/2007
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: David Sun
• Inventors: Ron, Uri, Miller, Eran, Sherman, Itay, Bychkov, Eyal
• Granted Patent: US 7,795,842 B2
• Time in Patent Office: Days
• US Class Current: 320/136
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 9/002 in which a reserve is maintained in an energy source by disconnecting non-critical loads, e.g. maintaining a reserve of charge in a vehicle battery for starting an engine
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A power management system for a mobile electronic device, including a microprocessor for continually monitoring a voltage of a battery within a mobile electronic device, wherein the device can operate in either a standalone mode powered by the battery, or in an externally powered mode, and wherein the battery is charged when the device is in external power mode, and a power manager coupled with said voltage meter, for controlling operation of the device according to the following logic: if the monitored voltage falls below an upper turn-on threshold, UTOT, during operation of the device in standalone mode, but is above a lower turn-on threshold, LTOT, then automatically turning the device off, and enabling the device to be turned on in an emergency mode, wherein at least one emergency action is enabled, and if the monitored voltage falls below LTOT during operation of the device in standalone mode, then automatically turning the device off, and preventing the device from being turned on. A method is also described and claimed.

Claims

1. A method for power management for a mobile electronic device, comprising:

continually monitoring a voltage of a battery within a mobile electronic device, wherein the electronic device can operate in either a standalone mode powered by the battery, or in an externally powered mode, and wherein the battery is charged when the device is in external power mode;

if the monitored voltage falls below an upper turn-on threshold, UTOT, during operation of the device in standalone mode, but is above a lower turn-on threshold, LTOT,

then;

automatically turning the device off; and

enabling the device to be turned on in an emergency mode, wherein at least one emergency action is enabled; and

if the monitored voltage falls below LTOT during operation of the device in standalone mode,

then;

automatically turning the device off; and

preventing the device from being turned on.

2. The method of claim 1 wherein the mobile electronic device is a cellular telephone, and wherein the at least one emergency action comprises making an emergency phone call.

3. The method of claim 1 wherein the mobile electronic device is a cellular telephone, and wherein the at least one emergency action comprises making a speed dial phone call.

4. The method of claim 1 wherein LTOT is approximately 3.2V and UTOT is approximately 3.3V.

5. A power management system for a mobile electronic device, comprising:

a microprocessor for continually monitoring a voltage of a battery within a mobile electronic device, wherein the device can operate in either a standalone mode powered by the battery, or in an externally powered mode, and wherein the battery is charged when the device is in external power mode; and

a power manager coupled with said voltage meter, for controlling operation of the device according to the following logic;

if the monitored voltage falls below an upper turn-on threshold, UTOT, during operation of the device in standalone mode, but is above a lower turn-on threshold, LTOT,

then;

automatically turning the device off; and

enabling the device to be turned on in an emergency mode, wherein at least one emergency action is enabled; and

if the monitored voltage falls below LTOT during operation of the device in standalone mode,

then;

automatically turning the device off; and

preventing the device from being turned on.

6. The power management system of claim 5 wherein the mobile electronic device is a cellular telephone, and wherein the at least one emergency action comprises making an emergency phone call.

7. The power management system of claim 5 wherein the mobile electronic device is a cellular telephone, and wherein the at least one emergency action comprises making a speed dial phone call.

8. The power management system of claim 5 wherein LTOT is approximately 3.2V and UTOT is approximately 3.3V.

9. A method for power management for a battery within a mobile electronic device, comprising controlling transitions from one power mode to another power mode for a mobile electronic device, wherein the device can run on an internal battery or on an external power source, and wherein the device may be placed into (i) a fully operation power mode where the device can be turned on and operates normally (Mode I), (ii) a provisionally operation power mode where the device can be turned on for a pre-specified amount of time and used only for one or more emergency operations (Mode II), (iii) a critically operational power mode where the device operates normally but cannot be turned on after it is turned off (Mode III), and (iv) a non-operation mode where the device is turned off and cannot be turned on (Mode IV), comprising:

transitioning from Mode I to Mode II when the device is running on the internal battery and the voltage of the battery drops below an upper turn-on threshold (UTOT);

transitioning from Mode II to Mode IV when the device is running on the internal battery and the voltage of the battery drops below a lower turn-on threshold (LTOT);

transitioning from Mode IV to Mode III when the device is running on the external power source and the voltage of the battery rises above a power-on reset threshold (POR); and

transitioning from Mode III to Mode I when the device is running on the external power source and the voltage of the battery rises above LTOT.

10. The method of claim 9 wherein said controlling transitions further comprises:

transitioning from Mode II to Mode I when the device is connected to the external power source; and

transitioning from Mode III to Mode IV when the device is disconnected from the external power source.

11. A power management system for a mobile electronic device, comprising a power manager for controlling transitions from one power mode to another power mode for a mobile electronic device, wherein the device can run on an internal battery or on an external power source, and wherein the device may be placed into (i) a fully operation power mode where the device can be turned on and operates normally (Mode I), (ii) a provisionally operation power mode where the device can be turned on for a pre-specified amount of time and used only for one or more emergency operations (Mode II), (iii) a critically operational power mode where the device operates normally but cannot be turned on after it is turned off (Mode III), and (iv) a non-operation mode where the device is turned off and cannot be turned on (Mode IV), comprising circuitry for:

transitioning from Mode I to Mode II when the device is running on the internal battery and the voltage of the battery drops below an upper turn-on threshold (UTOT);

transitioning from Mode II to Mode IV when the device is running on the internal battery and the voltage of the battery drops below a lower turn-oh threshold (LTOT);

transitioning from Mode IV to Mode III when the device is running on the external power source and the voltage of the battery rises above a power-on reset threshold (POR); and

transitioning from Mode III to Mode I when the device is running on the external power source and the voltage of the battery rises above LTOT.

12. The power management system of claim 11 wherein said circuitry is also operative for:

transitioning from Mode II to Mode I when the device is connected to the external power source; and

transitioning from Mode III to Mode IV when the device is disconnected from the external power source.