资 源 简 介
Within the wide family of Switch Mode Power Supplies(SMPS), the Flyback converters represent the structure ofchoice for use in small and medium power applications. Forcompact designs and radio−frequency sensitiveapplications, e.g. TV sets or set−top boxes, Quasi− Resonantpower supplies start to take a significant market share overthe traditional fixed frequency topology. However, if thefeedback loop control is well understood with this latter, forinstance via a comprehensive literature and SPICE models,the situation differs for self−oscillating variable switchingfrequency structures where no model still exists. This articlewill show how a simple large−signal averaged SPICE modelcan be derived and used to ease the design work duringstability analysis.
