Patent ID: 7977921

Claim:
An apparatus including voltage conversion and charging circuitry for converting an alternating current (AC) voltage to a direct current (DC) voltage for charging a battery, comprising: first and second input electrodes to convey an AC voltage; first and second output electrodes to convey a DC output voltage; AC-to-DC voltage conversion circuitry coupled to said first and second input electrodes and responsive to said AC voltage by providing a first converted DC voltage; a first capacitance coupled to said AC-to-DC voltage conversion circuitry and responsive to said first converted DC voltage by charging to a first charged DC voltage; first DC-to-DC voltage conversion circuitry coupled to said first capacitance and responsive to said first charged DC voltage by providing a second converted DC voltage which is greater than said first charged DC voltage; a second capacitance coupled to said first DC-to-DC voltage conversion circuitry and responsive to at least said second converted DC voltage by charging to a second charged DC voltage; and second DC-to-DC voltage conversion circuitry coupled to said second capacitance and responsive to said second charged DC voltage by providing said DC output voltage which is less than said second charged DC voltage; wherein, during an absence of said first converted DC voltage following said charging of said first capacitance to said first charged DC voltage, said first DC-to-DC voltage conversion circuitry is further responsive to said second charged DC voltage by substantially maintaining said first charged DC voltage on said first capacitance for at least a predetermined time interval.