Switch mode power supply device

Abstract

A power supply device including a rectifying unit, a supplying unit, a controlling unit, a conversion unit and a detection unit is disclosed. The rectifying unit processes an alternating current (AC) voltage to generate a direct current (DC) voltage. The supplying unit generates an operation voltage according to an input voltage. The controlling unit receives the operation voltage and generating an enabling signal. The conversion unit transforms the DC voltage to generate an auxiliary voltage according to the enabling signal. The auxiliary voltage is not equal to the operation voltage. The detection unit detects the auxiliary voltage. When the auxiliary voltage is generated, the detection unit de-activates the supplying unit to stop generating the operation voltage.

Dependencies are inferred from the claim text.