Patent ID: 6329875
Filing Date: 2001-12-11
Classification: H03F

Abstract:
A power amplifier comprises: an input terminal; an output terminal; an N number of bypassable amplification circuits which are connected directly or indirectly in a sequential manner between said input terminal and said output terminal; an impedance conversion circuit which is connected directly or indirectly between said amplification circuit of a final stage and said output terminal; and a bias control circuit which controls said amplification circuits,each of said amplification circuits including a high-frequency switch circuit, and an amplifier which is connected directly or indirectly to said switch circuit,said bias control circuit controls power source voltages of said amplifiers and controls status of said switch circuit,each of the amplification circuits sequentially connected to each other and individually bypassable between said input and output terminals,wherein a switch circuit of a respective amplification circuit selectively bypasses the respective amplification circuit by connecting an output signal from a prior adjacent amplification circuit to an input of a next adjacent amplification circuit.