Patent ID: 8331875

Claim:
An amplifier for amplifying a positive-phase input signal to generate a positive-phase output signal and amplifying a negative-phase input signal to generate a negative-phase output signal, comprising: a first amplifier circuit to amplify the positive-phase input signal in order to obtain a first positive-phase signal and to amplify the negative-phase input signal in order to obtain a first negative-phase signal; and a second amplifier circuit which includes a first amplifier unit and a second amplifier unit, the first amplifier unit amplifying the positive-phase input signal to obtain a second positive-phase signal and amplifying the negative-phase input signal to obtain a second negative-phase signal, the second amplifier unit amplifying the positive-phase input signal to obtain a third positive-phase signal and amplifying the negative-phase input signal to obtain a third negative-phase signal, wherein the positive-phase output signal is a sum of the first positive-phase signal and the second positive-phase signal while the negative-phase output signal is a sum of the first negative-phase signal and the second negative-phase signal, or the positive-phase output signal is a sum of the first positive-phase signal and the third negative-phase signal while the negative-phase output signal is a sum of the first negative-phase signal and the third positive-phase signal.