Abstract: A switching converter in which an input voltage can be switched by means of at least one controlled switch to at least one primary winding of a transformer, with a control circuit for controlling the switch, to which control circuit a regulating signal in the sense of regulating at least one output voltage is sent, wherein the power supply of the control circuit takes place via the forward voltage of an auxiliary winding of the transformer, a rectifier, a capacitor and a series regulator, on the one hand, and, on the other hand, starting from the input voltage, via a current path and a storage capacitor, and the off-state voltage of an auxiliary winding, which is rectified by means of a rectifier, is additionally sent to the control circuit for power supply, wherein the rectified off-state voltage is used during the operation for supplying the control circuit as long as it has a sufficient voltage level.