A MULTI-BAND LOW NOISE AMPLIFIER WITH COMMON NEGATIVE FEEDBACK INDUCTOR

摘要

A multi-band low noise amplifier using a common negative feedback inductor is provided to reduce a size of a semiconductor chip by reducing the number of inductors by connecting the common negative feedback inductor to one terminal of an amplifying transistor. A plurality of band low noise amplifiers(100) include a gate inductor, an amplifying transistor(M1,M3,M5), and a variable capacitor. One side of the gate inductor is connected to an antenna. The other side of the gate inductor is connected to the gate of the amplifying transistor and amplifies the signal received in the antenna. A variable capacitor is connected between a source and a gate of the amplifying transistor. A common feedback inductor(200) is commonly connected to one terminal of each amplifying transistor comprising the plurality of band low noise amplifiers. The band low noise amplifier fixes the value of the common feedback inductor. The band low noise amplifier determines the input impedance by controlling the value of a gate inductor and a variable capacitor in each band to be amplified.