<p>A variable gain amplifier (VGA) having stable input impedance matching and a stable noise figure in spite of a variation of an amplification gain is provided. In an embodiment of the VGA, an amplification gain of an amplification unit (1200) is controlled by adjusting a voltage applied to the amplification unit (1200) by controlling a current to be output by a current supply source (1010), and stable input impedance matching and a stable noise figure are obtained.</p>
