| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply circuit that forcibly applies off-control to a switch means when a digital power supply is turned off, so as to avoid an unnecessary power supply from being supplied to a power amplifier, thereby saving power. SOLUTION: The power supply circuit for a transmission reception circuit has an integrated circuit 10 for integrating an analog circuit 11 operated by an analog power supply Vcc and a digital circuit 12 operated by a digital power supply Vdd and has a power amplifier 20, which is connected to the analog circuit 11 of the integrated circuit 10 and energized via a field effect transistor(Tr)1 conductive by a current flowing via the control terminal of the digital circuit 12 from a battery 40, and is provided with a Tr2 that forcibly interrupts the current flowing through the digital circuit 12 from the battery 40, when the digital power supply Vdd is turned off. |
