| 摘要 |
PROBLEM TO BE SOLVED: To provide a transmitter amplifier circuit for a mobile radio equipment in which current consumption is reduced at transmission of low power and the circuit configuration is simplified. SOLUTION: In the case of high power transmission, a transmission power control section 11 closes a power switch 16 to supply power to a power amplifier section 13, a signal switch 14 is thrown to the position of a contact (a) and a signal switch 15 is thrown to the position of a contact (c), an output signal from a low power transmission section 12 is given to the power amplifier section 13, at which the signal is amplified. An output level of the low power transmission section 12 is controlled so that the output of the power amplifier section 13 reaches a prescribed transmission power. In the case of low power transmission, the power switch 16 is open to shut power supply to the power amplifier section 13, the signal switch 14 is thrown to the position of a contact (b) and the signal switch 15 is thrown to the position of a contact (d) respectively and the output signal of the low power transmission section 12 is transmitted as a transmission signal SO without any amplification. |
