Patent ID: 7183853

Claim:
A feedback amplifier comprising: an amplifying circuitry including a transistor and a resistive element for amplifying a signal input from an input terminal and outputting an amplified signal: a feedback circuitry having an output terminal connected to an input terminal of said amplifying circuitry; a signal separating circuitry having an input terminal connected to an output terminal of said amplifying circuitry and an output terminal connected to an input terminal of said feedback circuitry; an output circuitry having an input terminal connected to the output terminal of said amplifying circuitry; and a level adjusting circuit for outputting a signal amplified by a transistor to a next stage, said level adjusting circuit having an output terminal connected both to input terminals of said signal separating circuitry and to said output circuitry, wherein the input terminal of said amplifying circuitry is supplied by way of feedback with only a signal which has passed through said signal separating circuitry and said feedback circuitry.