VARIABLE GAIN LOW-NOISE AMPLIFIER FOR A WIRELESS TERMINAL

摘要

A variable gain, low noise amplifier is described, which is suitable as the input amplifier for a wireless terminal, or as the pre-amplifier stage of a wireless terminal transmitter. The amplifier (MN1) may achieve variable gain by deploying a network of transistors (MP1-MPn) in a parallel array, each independently selectable by a PMOS switch (220), and providing the variable resistance for the resonant circuit (Rp, Lp). Power dissipation can also be mitigated by using a network of driving transistors, each independently selectable by a PMOS switch (220). The resonant frequency of the amplifier may be made tunable by providing a selection of optional pull-up capacitors (Cp'1-Cp'n).