Patent ID: 7924098
Filing Date: 2011-04-12
Classification: H03F,H03G,H04B

Abstract:
1. A high frequency amplifier circuit comprising: a signal input terminal and a signal output terminal; a first matching circuit an input terminal of which is connected to said signal input terminal; a gain control circuit an input terminal of which is connected to an output terminal of said first matching circuit; a first amplifier an input terminal of which is connected to an output terminal of said gain control circuit; a second matching circuit an input terminal of which is connected to an output terminal of said first amplifier; a second amplifier an input terminal of which is connected to an output terminal of said second matching circuit; a third matching circuit an input terminal of which is connected to an output terminal of said second amplifier, and an output terminal of which is connected to said signal output terminal; a reference voltage terminal; a reference voltage circuit a reference voltage input terminal of which is connected to said reference voltage terminal, and a plurality of reference voltage output terminals of which are connected respectively to a plurality of reference voltage input terminals of said gain control circuit; a control terminal connected to a control input terminal of said gain control circuit; first ground terminals connected to ground terminals of said gain control circuit; a first supply terminal connected to a supply terminal of said first amplifier; a second ground terminal connected to a ground terminal of said first amplifier; a second supply terminal connected to a supply terminal of said second amplifier; and a third ground terminal connected to a ground terminal of said second amplifier, wherein: on the basis of the relation between the voltage of said reference voltage input terminal and the voltage of said control terminal, the resistance value between the signal input terminal and the signal output terminal of said gain control circuit is adjusted, so that the signal level on said signal output terminal is continuously adjusted relative to the signal level inputted to said signal input terminal.