A Fly-buck converter is one of the multiple-output converters which has non-isolated and isolated outputs. The isolated output voltage suffers from poor voltage regulation characteristic since it is controlled indirectly. The parasitic capacitances and leakage inductance induce current dip at the non-isolated output during dead time between the high- and low-side switches, and the isolated output voltage is affected by this phenomenon. In this digest, the cross regulation of isolated voltage is analyzed. The 20-W prototype to power gate driver was built and tested to verify the analysis.
