Patent ID: 10326374

Abstract:
Presented is a converter circuit having main switching circuiton a primary side of a transformer, for controlling supply of a current to a storage inductor on the primary side when the main switching circuit is conductive. The convertor circuit comprises: a control circuit operatively coupled to the main switching circuit and for controlling the main switching circuit, the control circuit comprising a control capacitor adapted to enable the control circuit and turn off the main switching circuit; an auxiliary inductor magnetically coupled to the storage inductor and adapted to trigger the control circuit to operate and turn off the main switching circuit in response to a voltage change in the storage inductor when the main switching circuit being conductive; and a charging circuit coupled between the auxiliary inductor and the control capacitor and adapted to enable the auxiliary inductor to charge the control capacitor. The charging circuit comprises first and second charging paths within the primary side between the auxiliary inductor and the control capacitor, the first charging path being conductive and the second charging path being conductive when a voltage across the auxiliary inductor is above a threshold value.