The present invention relates to a drive circuit for a switch (T)
connected to a rectifier arrangement in a switching converter which
provides an output voltage (Vout) from an input voltage (Vin), the drive
circuit having the following features: a controller arrangement (40)
having at least one control amplifier (OTA1) and a compensation network
(41) having at least one capacitor (C4, C5), a signal dependent on the
output voltage (Vout) being fed to said controller arrangement and the
latter providing a control signal (S4), a protection circuit (30), which
is designed to detect at least one critical state of the switching
converter and which provides a protection signal (S3) in a manner
dependent on the presence of a critical state, the protection circuit
(30) having a discharge circuit (32) coupled to the compensation network
(41), a signal generating circuit (20), to which the control signal (S4)
and the protection signal (S3) are fed and which provides a drive signal
(S5) having drive pulses according to the protection signal, the duty
ratio of which drive signal is dependent on the control signal (S4).