Patent ID: 9673765
Date: 2017-06-06
CPC Classifications: H03F

Claim:
1. A signal amplifier comprising: a band suppression filter configured to suppress a preset band among bands included in an input signal; a first common source-type amplifier connected between a supply terminal of a driving voltage and a ground terminal and configured to amplify a first input signal separated from an output signal of the band suppression filter in a common input node to provide a first amplified signal to a common output node; a second common source-type amplifier stacked between the supply terminal of the driving voltage and the ground terminal together with the first common source-type amplifier and configured to amplify a second input signal separated from the output signal of the band suppression filter in the common input node to provide a second amplified signal to the common output node; and an output matcher configured to match levels of impedance between the common output node and an output terminal and to transfer a combined signal generated by combining the first amplified signal and the second amplified signal with each other in the common output node to the output terminal, wherein the first and second common source-type amplifiers form a single current path between the supply terminal of the driving voltage and the ground terminal, and wherein the output matcher comprises a source follower amplifier configured to transfer the combined signal to the output terminal.