A current modulator for supplying a modulated supply current (I PA) to a power amplifier, the current modulator comprising: an amplifier having a first input terminal to receive an amplitude modulation signal, and an output terminal to supply a modulation control signal responsive to the amplitude modulation signal; an output circuit including an output transistor (Q 2) comprising a gate terminal for receiving the modulation control signal; a source terminal coupled to a supply voltage and a drain terminal for supplying the modulated supply current (I PA) and an operating voltage (V PA) to the power amplifier; a reference transistor (Q 1, Q 4) having a known geometric scaling relative to the output transistor (Q 2), comprising a gate terminal for receiving the modulation control signal, a source terminal coupled to the supply voltage and a drain terminal to supply a reference current (I REF) proportional to the modulated supply current (I PA); a detection circuit comprising a first differential amplifier having a sense input coupled to the drain terminal of the output transistor (Q 2), a feedback input coupled to the drain terminal of the reference transistor (Q 1, Q 4), and an output to supply an inferential sense signal as a function of the operating voltage (V PA) to be supplied to the power amplifier and the reference current (I REF); and a reference control element comprising a control transistor (Q 3, Q 5) disposed in series with the reference transistor (Q 1, Q 4) and comprising an input to receive the inferential sense signal from the detection circuit, and an output to provide a reference operating voltage (V REF) at the drain terminal of the reference transistor (Q 1, Q 4), wherein the control transistor (Q 3, Q 5) is configured to be controlled by the detection circuit with the first differential amplifier in a closed loop configuration to maintain the reference operating voltage (V REF) equal to the operating voltage (V PA) to be supplied to the power amplifier. an amplifier having a first input terminal to receive an amplitude modulation signal, and an output terminal to supply a modulation control signal responsive to the amplitude modulation signal; an output circuit including an output transistor (Q 2) comprising a gate terminal for receiving the modulation control signal; a source terminal coupled to a supply voltage and a drain terminal for supplying the modulated supply current (I PA) and an operating voltage (V PA) to the power amplifier; a reference transistor (Q 1, Q 4) having a known geometric scaling relative to the output transistor (Q 2), comprising a gate terminal for receiving the modulation control signal, a source terminal coupled to the supply voltage and a drain terminal to supply a reference current (I REF) proportional to the modulated supply current (I PA); a detection circuit comprising a first differential amplifier having a sense input coupled to the drain terminal of the output transistor (Q 2), a feedback input coupled to the drain terminal of the reference transistor (Q 1, Q 4), and an output to supply an inferential sense signal as a function of the operating voltage (V PA) to be supplied to the power amplifier and the reference current (I REF); and a reference control element comprising a control transistor (Q 3, Q 5) disposed in series with the reference transistor (Q 1, Q 4) and comprising an input to receive the inferential sense signal from the detection circuit, and an output to provide a reference operating voltage (V REF) at the drain terminal of the reference transistor (Q 1, Q 4), wherein the control transistor (Q 3, Q 5) is configured to be controlled by the detection circuit with the first differential amplifier in a closed loop configuration to maintain the reference operating voltage (V REF) equal to the operating voltage (V PA) to be supplied to the power amplifier.