Patent ID: 7528659

Claim:
A fully differential amplification device comprising: a differential amplifier that is fed with a positive input signal and a negative input signal, and outputs a positive output signal and a negative output signal; an output common voltage generation circuit that is fed with and amplifies the positive output signal and the negative output signal outputted from the differential amplifier, generates a positive amplification signal and a negative amplification signal, and generates an output common voltage from the positive amplification signal and the negative amplification signal; a common mode feedback comparator that compares the output common voltage of the output common voltage generation circuit with a predetermined reference voltage, and feeds back a result of the comparison of the output common voltage with the predetermined reference voltage to the differential amplifier as a common mode feedback signal to thereby make the output common voltage coincide with the reference voltage; and a current source that always feeds current to an input portion, in the output common voltage generation circuit, to which the positive output signal and the negative output signal are inputted.