Patent ID: 8441821

Claim:
An AC-to-DC converter, comprising: a first converter operable for converting an AC voltage to a first DC voltage; a second converter coupled to said first converter and operable for converting said first DC voltage to a second DC voltage; a sense circuit coupled to said first and second converters and operable for providing a first sense signal indicative of said first DC voltage and providing a second sense signal indicative of said AC voltage; a controller coupled to said first and second converters and operable for controlling said first and second DC voltages; an enabling circuit coupled to said sense circuit and operable for generating a control signal to said controller to disable both said first converter and said second converter by comparing said first sense signal to a first threshold voltage and comparing said second sense signal to a second threshold voltage; and a signal generator, coupled to said enabling circuit, operable for receiving said control signal and generating a first pulse signal and a second pulse signal according to said control signal to control said first and second DC voltages.