Patent ID: 7898339
Filing Date: 2011-03-01
Classification: H03F

Abstract:
1. An amplifier circuit comprising an amplifier unipolar transistor having a gate as an input terminal of the amplifier circuit; a diode-connected transistor block for negative feedback source impedance constituted by series-parallel connection of the limited number (including 0 piece) of the diode-connected unipolar transistors for connecting a gate and a drain so as to make between the drain and source into a diode and connected to the source side of the amplifier unipolar transistor; a diode-connected transistor block for load constituted by the series-parallel connection of the limited number of the diode-connected unipolar transistors connecting a gate and a drain so as to make between the drain and source into a diode and connected to the drain side of the amplifier unipolar transistor; and a voltage output terminal connected to a drain-side end of the amplifier unipolar transistor of the diode-connected transistor block for load, wherein a voltage gain is determined by a ratio of impedance of the sum of source impedance of the amplifier unipolar transistor and the impedance of the diode-connected transistor block for negative feedback source impedance to the impedance of the diode-connected transistor block for load.