US Patent 7598804 Amplifier circuit

There is provided an amplifier circuit including a plurality of unit amplifiers connected in parallel to an input signal terminal, wherein each of the unit amplifiers includes: a first switch switching an input signal inputted from the input signal terminal; a first field effect transistor having a gate connected to the input signal terminal via the first switch and amplifying the input signal of the input signal terminal to output the amplified input signal; a second switch connected in parallel to the first switch and switching the input signal of the input signal terminal at a complementary timing to a switching timing of the first switch; and a capacitor connected to the input signal terminal via the second switch.