Amplifying apparatus

摘要

There is provided an amplifying apparatus which can prevent characteristic deterioration while reducing costs. The amplifying apparatus includes a first amplifier connected between an input terminal to which a high-frequency signal is input and an output terminal through which the high-frequency signal is output, including a bipolar transistor, and amplifying the high-frequency signal input from the input terminal; a second amplifier including a bipolar transistor, amplifying the high-frequency signal input from the input terminal, and having a lower maximum output power than that of the first amplifier; and a switching unit connected between the second amplifier and the output terminal, and selectively outputting the high-frequency signal amplified by the second amplifier through the output terminal.

主权项

1. An amplifying apparatus comprising:
a first amplifier connected between an input terminal to which a high-frequency signal is input and an output terminal through which the high-frequency signal is output, including a bipolar transistor, and amplifying the high-frequency signal input from the input terminal; a second amplifier including a bipolar transistor, amplifying the high-frequency signal input from the input terminal, and having a lower maximum output power than that of the first amplifier; and a switching unit connected between the second amplifier and the output terminal, and selectively outputting the high-frequency signal amplified by the second amplifier through the output terminal, the switching unit including:
an impedance transformer installed on a signal line between the second amplifier and the output terminal, and performing impedance conversion,a first bipolar transistor in which an emitter is grounded, a collector is connected to the signal line, and a current according to a control voltage for controlling a switching operation in the switching unit is applied to a base, anda second bipolar transistor in which a collector is grounded, an emitter is connected to the signal line, and the current according to the control voltage is applied to a base.