A drive circuit for activating a switch in a switching converter, which
has output Terminals for providing an output voltage, and in which a
feedback signal that varies with the output voltage is available. The
drive circuit comprises: a capacitive storage element, a
charging/discharging circuit connected to a first terminal of the
capacitive storage element, to which at least one load signal is fed,
that adopts at least a first and second state according to at least one
control signal, and which is designed in such a way to charge the
capacitive storage element cyclically in the first state up to a first
limit value and to discharge it until it reaches a second limit value,
and in the second state to only charge the capacitive storage element, a
load signal generation circuit to which the feedback signal is fed and
which produces at least one load signal, at least one operating mode
circuit to which a charge state signal, which varies with the charge
state of the capacitive storage element, and the first control signal are
fed, and which is designed to set an initial operating state of the drive
circuit (100) in accordance with the aforementioned input signals, an
oscillator circuit to which the charge state signal is fed, and which
provides an oscillating signal with a frequency that varies according to
the charge state signal, a drive signal generation circuit to which the
oscillating signal and the feedback signal are fed, and which provides
the drive signal.