a lower - cost and more precise control methodology of regulating the output voltage of a flyback converter from the primary side is provided , which works accurately in either continuous voltage mode and discontinuous mode , and can be applied to most small , medium and high power applications such cell phone chargers , power management in desktop computers and networking equipment , and , generally , to a wide spectrum of power management applications . two highly integrated semiconductor chips based on this control methodology are also described that require very few components to build a constant voltage flyback converter .