Adjustable cut-off voltage for mobile device battery
View Patent ↗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.
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;
when the monitored voltage is below an upper turn-on threshold, UTOT, but is above a lower turn-on threshold, LTOT, then discriminating between standalone and external power modes, comprising:
when the device is operating in standalone mode:
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 other device actions are disabled; and
when the device is operating in external power mode:
enabling the device to be turned on; and
enabling all device actions when the device is turned on; and
when the monitored voltage is below the lower turn-on threshold (LTOT) but is above a power-on reset threshold, POR, then further discriminating between standalone and external power modes, comprising:
when the device is operating in standalone mode:
automatically turning the device off; and
preventing the device from being turned on; and
when the device is operating in external power mode:
enabling all device actions if the device is already turned on; and
preventing the device from being turned on when the device is turned off.
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 the power-on reset threshold (POR) is approximately 2.7V, the lower turn-on threshold (LTOT) is approximately 3.2V, and the upper turn-on threshold (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 microprocessor, for controlling operation of the device according to the following logic:
when the monitored voltage is below an upper turn-on threshold, UTOT, but is above a lower turn-on threshold, LTOT, then discriminating between standalone and external power modes, comprising:
when the device is operating in standalone mode:
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 other device actions are disabled; and
when the device is operating in external power mode:
enabling the device to be turned on; and
enabling all device actions when the device is turned on; and
when the monitored voltage is below the lower turn-on threshold (LTOT) but is above a power-on reset threshold, POR, then further discriminating between standalone and external power modes, comprising:
when the device is operating in standalone mode:
automatically turning the device off; and
preventing the device from being turned on; and
when the device is operating in external power mode:
enabling all device actions if the device is already turned on; and
preventing the device from being turned on when the device is turned off.
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 the power-on reset threshold (POR) is approximately 2.7V, the lower turn-on threshold (LTOT) is approximately 3.2V, and the upper turn-on threshold (UTOT) is approximately 3.3V.