Amplification device and processes capable of miniaturization in a device for performing linear amplification and switching amplification operations on incoming signals are provided. The amplifying device includes a first amplifying unit for amplifying an input signal and outputting a first output signal, the input switch unit connected in parallel with the first amplifying unit for performing a switching operation by an input signal and outputting a switch output signal, and a second amplifying unit for amplifying a first output signal or a switch output signal and outputting a second output signal, and the first amplifying unit or the input switch unit operates based on the type of the input signal.