A generator capable of supplying one or more output signals with a modulated cyclic ratio includes one or more formatting circuits each processing one input signal and one or more class D amplifiers powered with a power supply voltage and being driven by a corresponding one of the formatting circuits. Each formatting circuit has a counter-reaction loop and uses a reference voltage for which the average value is equal to half the power supply voltage. The corresponding output signal is thus corrected for any variations in the power supply voltage.