This paper presents practical design guidelines for off-line flyback converters using Fairchild Power Switch (FPS). The step-by-step design procedure described in this paper helps engineers to design switched mode power supply (SMPS) easily. In order to make the design process more efficient, a software design tool called FPS design assistant that contains all the equations described in this paper is also provided. The design procedure is verified through experimental prototype converter.
This document presents practical design guidelines for creating off-line flyback converters that employ the Fairchild Power Switch (FPS). It outlines a systematic procedure to simplify the inherently complex process of switching mode power supply (SMPS) design, which typically involves numerous trade-offs and iterations. The guide covers essential steps from defining system specifications to designing the feedback loop.
It is required to set estimated efficiency Eg=0.7~0.75 for low voltage output applications.
It is typical to select the DC link capacitor as 2-3uF per watt of input power for universal input range (85-265Vrms).
It is generally accepted that a DCM flyback converter is designed to operate at the boundary of DCM and CCM with minimum input voltage and maximum load.