Patent ID: 7460378

Claim:
A circuit arrangement for protecting an electronic converter against overloads, the arrangement including: a low impedance path selectively activatable to prevent ignition of said electronic converter, said low impedance path including an electronic switch, wherein said electronic converter is subject to ignition at each half-cycle of a respective supply signal and wherein said electronic switch is activatable to prevent ignition of said electronic converter for a given half-cycle of said supply signal if the charge voltage of said control capacitor is above said predetermined threshold at the beginning of said given half-cycle; a control capacitor whose charge voltage controls said electronic switch, wherein said low impedance path is activated to prevent ignition of said electronic converter if the charge voltage of said control capacitor is above a predetermined threshold; a first generator for charging said control capacitor, said first generator activatable in the case of a first current overload condition of said electronic converter; and a second generator for further charging said control capacitor, said second generator activatable in the case of a second overload condition of said electronic converter, said second overload condition being heavier than said first overload condition, wherein said first generator and said second generator are configured for charging said control capacitor as long as said electronic converter is ignited, wherein in the case of said second overload condition, the charge voltage of said control capacitor reaches a higher level and remains above said predetermined threshold thus keeping said electronic switch activated to prevent ignition of said electronic converter for a longer time than in the case of said first overload condition.