Cordless phone with backup battery power backup in case of power failure

摘要

The present invention relates to a radiotelephone which receives a backup of a spare battery power, which is a spare power supply at the time of correction, and applies it to the main body, and operates the main body even during a power failure. A radiotelephone having a main body and a battery, the portable telephone having a silent communication with the main body, and a spare battery which is a spare part of the battery of the portable device, wherein the main body inputs a DC power source having an unstable voltage width from the DC power supply device. A wireless transmitter / receiver for converting a voice signal into a wireless signal and transmitting the received wireless signal, and converting a received signal into a wireless signal; and a microcomputer for controlling the wireless transmitter / receiver by receiving DC power applied from the constant voltage power supply unit; The spare battery connected to the output terminal with a DC power input from the DC power supply unit It is provided between a spare battery charging unit for charging, a portable charging unit for charging a battery of the portable device connected to an output terminal with a DC power input from the DC power supply device, an output side of the spare battery charging unit, and an input side of the constant voltage power supply unit. And a power backup unit for supplying power of the spare battery to the constant voltage power supply unit.