High frequency amplifier in an integrated circuit

Abstract

The invention concerns an integrated circuit amplifier designed to supply an amplified signal at a power of a few hundreds of milliwatts at frequencies from one to several Gigahertz. The final stage of the amplifier comprises two signal amplification input points E and E′ receiving in differential mode a signal to be amplified, and four main transistors of the same type of conductivity, each having a base, an emitter and a collector, including a first transistor or output transistor mounted in common emitter configuration, whereof the collector is linked to the output of the integrated circuit, a second transistor mounted in voltage follower configuration between the point E and the base of the output transistor, a third transistor mounted in common emitter configuration, having its collector linked to the base of the output transistor, a fourth transistor mounted in voltage follower configuration having its base linked to the point E′ and its emitter linked to the base of the third transistor, the circuit also comprising a first current source linked to the base of the first transistor and a second current source linked to the base of the third transistor and to the emitter of the fourth transistor.

Dependencies are inferred from the claim text.