Abstract: Interleaved flyback DC to DC converters are provided comprising a first and a second switching transistors controllable with 180.degree. phase shift and a first and a second flyback transformers. A primary winding of each transformer is coupled in a series circuit with the corresponding switching transistor. A secondary winding of the first transformer is coupled with the secondary winding of the second transformer via a first catch diode and both said secondary windings are coupled to an output filter capacitor via a second and a third catch diode, correspondingly. When discharging to the output filter capacitor, the transformers interlock each other. By interlocking, non-pulsating output current is generated and voltage across switching transistors is reduced. A secondary quasi-resonant snubber network relieves voltage spikes across the switching transistors. A common magnetic core of the transformers cuts the cost and the size of the interleaved flyback converters.