Signal amplifier arrangeable in two different configuration modes

Abstract

A signal amplifier includes four amplifier stages which can be arranged in two different configuration modes, a first configuration mode in which a series arrangement of two loads is arranged between output terminals of a first and a third one of the amplifier stages, a reference potential being applied to a node between the loads, a first signal to be amplified being applied to an input of the first amplifier stage, and a second signal to be amplified being applied to an input of the third amplifier stage, and a second configuration mode in which a first one of the loads is arranged between the output terminal of the first amplifier stage and an output terminal of a second amplifier stage, and a second one of the loads is arranged between the output terminal of the third amplifier stage and an output terminal of a fourth amplifier stage, and the first signal to be amplified being applied to an input of the first amplifier stage and an input of the second amplifier stage and the second signal to be amplified being applied to the input of the third amplifier stage and an input of the fourth amplifier stage. The signal amplifier also includes a switching device for switching the signal amplifier selectively to one of the two configuration modes. A particularly low-loss and low-distortion operation of such a signal amplifier is achieved by a detection device for detecting the distortion factor of the signal at the output terminal of the first and/or the third amplifier stage and for actuating the switching device in dependence on the detected value of the distortion factor.

Dependencies are inferred from the claim text.