AMPLIFIER

The purpose of the present invention is to simplify adjustment of a gain of an amplifier. In a first transistor, an applied input signal is input to a gate terminal and an electric current according to the input signal flows. A load part is connected to a drain terminal of the first transistor. In a second transistor, a gate terminal is connected to the load part and an electric current accordingto change of voltage of the drain terminal of the first transistor flows. To a first resistance, a source terminal of the first transistor and a drain terminal of the second transistor are connected in common and electric currents from the first transistor and the second transistor flow. A third transistor feeds an electric current substantially equal to that of the second transistor. To an outputterminal, the electric current fed from the third transistor is output. 本发明的目的是简化放大器增益的调节。在第一晶体管中，施加的输入信号被输入到其栅极端子并且取决于输入信号的电流流动。负载部连接到第一晶体管的漏极端子。在第二晶体管中，栅极端子连接到负载部，并且取决于第一晶体管的漏极端子的电压变化的电流流动。第一晶体管的源极端子和第二晶体管的漏极端子共同连接到第一电阻，并且来