US Patent 7358811 CMOS variable gain amplifier for controlling dB linear gain

Provided is a complementary metal oxide semiconductor variable gain amplifier controlling a dB linear gain and a method of controlling the dB linear gain. The complimentary metal oxide semiconductor variable gain amplifier includes: first through fourth transistors differentially receiving first and second input voltages and amplifying the first and second input voltage using a predetermined gain; fifth and sixth transistors controlling a transconductance according to a control voltage to control the predetermined gain; and first and second resistors generating an output voltage having the predetermined gain according to an output current generated by the fifth and sixth transistors.