Patent ID: 7834704

Claim:
A low-noise amplifier circuit comprising: a signal amplifier unit having an input terminal and an output terminal, for amplifying an input signal, a load unit connected between the output terminal and a power supply terminal, for converting a current signal from the output terminal into a voltage signal, a RF signal supplier connected to the input terminal, for supplying a RF signal, a resonance frequency control circuit for controlling a resonance frequency of the load unit according to a frequency of an RF signal supplied from the RF signal supplier, a first transistor having drain, gate, and source terminals connected to a first output terminal, a first input terminal, and a first node, respectively, a second transistor having drain, gate, source terminals connected to a second output terminal, a second input terminal, and the first node, respectively, and a current source connected between the first node and a ground terminal, and said load unit comprises a first inductor connected between the power supply terminal and the first output terminal, a second inductor connected between the power supply terminal and the second output terminal, and a capacitor connected between the first output terminal and the second output terminal, wherein at least either of inductances of the first and second inductors or a capacitance of the capacitor is variable.