Patent ID: 8031006

Claim:
A low noise amplifier, comprising: an input stage, the input stage including a first transistor configured to receive an input signal, the first transistor having a first input impedance and a first transconductance, and a second transistor connected to the first transistor, the second transistor having i) a second input impedance lower than the first input impedance and ii) a second transconductance greater than the first transconductance; and a bias circuit configured to i) provide a first bias signal to bias the first transistor into a triode region and ii) provide a second bias signal to bias the second transistor into a saturation region, wherein, due to i) the second input impedance being lower than the first input impedance, ii) the second transconductance being greater than the first transconductance, and iii) the first transistor being biased into the triode region, a change in the input signal to the first transistor causes a linearly proportional change in a conductance of the first transistor, and a voltage at a junction between the first transistor and the second transistor remains substantially constant.