A control circuit for a buck converter configured to provide via two output terminals (202a, 202b) an output voltage ( V out) and an output current ( i out), the control circuit comprising: - a first terminal configured to be connected to an electronic switch of said buck converter; - a second terminal configured to receive a feedback signal indicative of said output voltage ( V out); - two terminals configured to be connected to said two output terminals (202a, 202b) of said buck converter; - an error amplifier (212; 202, 204) configured to generate an error signal ( V comp) as a function of said feedback signal and a reference signal ( V ref); - a pulse generator circuit configured to generate a pulsed signal having switching cycles where said pulsed signal is set to high for a first duration and to low for a second duration, wherein said pulse generator circuit is configured to vary said first and/or said second duration as a function of said error signal ( V comp); and - a driver circuit configured to generate a drive signal ( DRV 1) at said first terminal as a function of said pulsed signal; - a variable load connected between said two terminals, wherein said variable load is configured to absorb a current ( i F) determined as a function of a control signal; and - a detector circuit configured to monitor a first signal ( FB; CS) indicative of a negative transient of said output current ( i out) and generate said control signal as a function of said first signal ( FB; CS); characterized in that said detector circuit is configured to - monitor a second signal ( V comp; CS) indicative of said output current ( i out); - verify whether said first signal (FB; CS) indicates a negative transient of said output current ( i out); - in response to said verification, when said first signal (FB; CS) does not indicate a negative transient of said output current ( i out), store said monitored second signal ( V comp; CS); and - in response to said verification, when said first signal ( FB; CS) indicates a negative transient of said output current ( i out), generate said control signal as a function of the difference ( i 3) between said stored second signal ( V comp; CS) and said monitored second signal ( V comp; CS), such that said variable load absorbs a current ( i F) being proportional to the difference ( i 3) between said stored second signal ( V comp; CS) and said monitored second signal ( V comp; CS). - a first terminal configured to be connected to an electronic switch of said buck converter; - a second terminal configured to receive a feedback signal indicative of said output voltage ( V out); - two terminals configured to be connected to said two output terminals (202a, 202b) of said buck converter; - an error amplifier (212; 202, 204) configured to generate an error signal ( V comp) as a function of said feedback signal and a reference signal ( V ref); - a pulse generator circuit configured to generate a pulsed signal having switching cycles where said pulsed signal is set to high for a first duration and to low for a second duration, wherein said pulse generator circuit is configured to vary said first and/or said second duration as a function of said error signal ( V comp); and - a driver circuit configured to generate a drive signal ( DRV 1) at said first terminal as a function of said pulsed signal; - a variable load connected between said two terminals, wherein said variable load is configured to absorb a current ( i F) determined as a function of a control signal; and - a detector circuit configured to monitor a first signal ( FB; CS) indicative of a negative transient of said output current ( i out) and generate said control signal as a function of said first signal ( FB; CS); - monitor a second signal ( V comp; CS) indicative of said output current ( i out); - verify whether said first signal (FB; CS) indicates a negative transient of said output current ( i out); - in response to said verification, when said first signal (FB; CS) does not indicate a negative transient of said output current ( i out), store said monitored second signal ( V comp; CS); and - in response to said verification, when said first signal ( FB; CS) indicates a negative transient of said output current ( i out), generate said control signal as a function of the difference ( i 3) between said stored second signal ( V comp; CS) and said monitored second signal ( V comp; CS), such that said variable load absorbs a current ( i F) being proportional to the difference ( i 3) between said stored second signal ( V comp; CS) and said monitored second signal ( V comp; CS).