Abstract: An amplifier includes an output for feeding a load, a voltage generator presenting very high linearity and very low output impedance, and a current source having its output connected to the output of the voltage generator at a coupling point connected to the output. The output of the voltage generator is connected directly to the coupling point without any resistive element being interposed between them. A control stage controls the current source from the current delivered by the voltage generator. The control stage for controlling the current source includes current measurement elements for measuring the current delivered by the voltage generator, and the elements are disposed solely upstream from the output for feeding the load.