초록 ▼

An emergency cellular telephone includes a low power timer which receives power directly from the battery and runs continuously. The timer periodically initiates battery tests and, if appropriate, low battery warnings, while the telephone is in an OFF state. The timer "wakes up" (powers-up) the tele

An emergency cellular telephone includes a low power timer which receives power directly from the battery and runs continuously. The timer periodically initiates battery tests and, if appropriate, low battery warnings, while the telephone is in an OFF state. The timer "wakes up" (powers-up) the telephone at a predetermined interval (for example, once per day or once per week). After each timer-controlled "wake-up", the processor performs a test to estimate remaining battery capacity (by measuring battery voltage with a load on the battery or other conventional battery charge monitoring techniques). If the remaining battery capacity is adequate, the telephone processor turns off and the timer is re-started. If the remaining battery capacity is low, a warning is issued. The low battery warning may use conventional methods, such as an aural or visual warning from the phone. Additionally, the warning may consist of an automatic wireless telephone call to a predetermined number which is loaded into the telephone by the user or carrier via the keypad and/or a system connector. The number called can be the user's land line number, another cellular number or a carrier number. The warning sent via the phone call can consist of audible tones, combination of tones, voice synthesized message or data.

대표청구항 ▼

[ What is claimed is:] [1.] A wireless communication device operable in a plurality of states including a powered-off state and a battery test state, comprising:a battery having a charge level for supplying electrical power to the device; a timer counter coupled to the battery and operable in the po

[ What is claimed is:] [1.] A wireless communication device operable in a plurality of states including a powered-off state and a battery test state, comprising:a battery having a charge level for supplying electrical power to the device; a timer counter coupled to the battery and operable in the powered-off state for causing the device to enter the battery test state when a predetermined period of time has elapsed with the device in the powered-off state, and said counter controls a switch to apply power from the battery to a battery charge level monitoring circuit and to a processor during the battery test state;the battery charge level monitoring circuit switchably coupled to the battery for generating a battery charge level signal proportional to the battery charge level during the battery test state;the processor is switchably coupled to the battery charge level monitoring circuit for sensing the battery charge level signal during the battery test state, and generating an alarm signal if the battery charge level is below a predetermined level, andwherein generation of the alarm signal includes powering a communication circuit in the device to establish an automatic wireless communication to a preselected telephone number to transmit a low battery charge warning.