Start-up circuit for power converters with wide input voltage range

A start-up circuit comprising:

• a switching-device control circuit arranged to receive an input voltage and to provide a switching-device control signal;
• a switching device arranged to be controlled by the switching-device control signal, to receive the input voltage, and to provide a start-up signal;
• a power-converter control circuit arranged to receive the start-up signal and to provide a power-converter control signal;
• and
• a power converter arranged to receive the power-converter control signal and to provide an auxiliary output signal;
• wherein
• the switching-device control circuit is arranged to receive the auxiliary output signal such that, when the auxiliary output signal reaches a predetermined level, current of the input voltage flowing through the switching device and current of the input voltage flowing through the switching-device control circuit are interrupted, causing the switching device to stop providing the start-up signal.