| 摘要 |
PROBLEM TO BE SOLVED: To provide a Doherty amplifier which maximizes efficiency at low cost with high stability, while enhancing power efficiency, even if a wide band signal and a multi-band signal are used. SOLUTION: A frequency information obtaining part 109 obtains frequency information on signals input from an input terminal 101. A control circuit 110 stores a frequency expected to be used and a control signal for outputting a supply voltage corresponding to the frequency, and outputs the control signal according to frequency information on the input signal to a DC/DC conversion circuit 112. The DC/DC conversion circuit 112 converts the supply voltage output from an external power part 111 into a voltage indicated by the control signal output from the control circuit 110, and applies the voltage to a bias line 104 of a main amplifier 103 and a bias line 107 of an auxiliary amplifier 106. COPYRIGHT: (C)2011,JPO&INPIT |
