| 摘要 |
PURPOSE: A backup battery circuit for a wireless phone is provided to achieve a long time for the call when power failure by adding a switch and a diode. CONSTITUTION: A backup battery circuit for a wireless phone comprises a voltage detector(25), a first switch(24), and a charging controller(22). The voltage detector(25) detects the charging power of the backup battery(23) so as to monitor if the charging power is discharged under a preset power. The first switch(24) cuts off the connecting with the backup battery according to the controlling of the voltage detector so as to prevent over discharge of the backup battery. The charging controller(22) is connected to the first switch, and provides a telephone conversation path between the backup battery and circuit power supply terminal in case of power failure, and a telephone conversation path and charging path between the backup battery and circuit power supply terminal in case of line's busy or holding telephone.
|
