| 摘要 |
A compact power supply apparatus is favorable for a reduction in size of a mobile communication terminal having a receiver and baseband signal processor (30), a transmitter (42) and a power amplifier (44). The power supply apparatus includes a DC/DC (20) converter for converting a DC voltage from a battery. In a reception mode of the mobile communication terminal, the power supply apparatus regulates the DC voltage converted by the DC/DC converter and supplies the regulated DC voltage to the receiver and baseband signal processor. In a transmission mode, the power supply apparatus converts the DC voltage converted by the DC/DC converter to a DC voltage corresponding to a transmission AGC (Automatic Gain Control) voltage determined depending on a transmission power and supplies the converted DC voltage to the receiver and baseband signal processor, the transmitter and the power amplifier. Since the power supply apparatus uses a single DC/DC converter and adaptively varies the output voltage of the DC/DC converter according to the transmission power in the transmission mode, it is favorable for a reduction in size of the mobile communication terminal and for a reduction in power loss of the voltage regulators and the power amplifier, thereby maximizing the power effciency and extending the battery life. <IMAGE> |
