Method and apparatus for reducing spike voltage of switching power supply

摘要

an input filter capacitor of the present invention; A switching type power supply including a switching element, the core of the transformer; a first input winding wound around the core of the transformer and controlling the flow of current by a switching operation of the switching element; a second input winding wound around the core of the transformer and controlling the flow of current by a switching operation of the switching element; and a transformer wound around a core of the transformer and including an output winding coupled to the first input winding and the second input winding to extract energy; an inductor; And including a first capacitor, The first input winding of the transformer is tightly coupled with the second input winding, The inductor and the first input winding are connected in series, and a first capacitor is connected between the serially connected inductor and one end of the first input winding and the other end of the first input winding, The inductor, the first input winding, the second input winding, and the switching element are connected in series between the two terminals of the input filter capacitor.