A clock-signal generator circuit, for generating an output clock signal starting from an input clock signal, includes: a monostable stage having a clock input configured to receive the input clock signal, a control input configured to receive a control signal, and an output configured to supply the output clock signal having a duty cycle variable as a function of the control signal; and a feedback loop, operatively coupled to the monostable stage for generating the control signal as a function of a detected value, and of a desired value, of the duty cycle of the output clock signal.