Introduction

Flyback switched mode power supplies (SMPS) are among the most frequently used power circuits in household and consumer electronics. The basic function of an SMPS is to supply regulated power to the load on the secondary, or output side. An SMPS typically incorporates a power transformer, secondary-side rectifier diodes, a switching semiconductor device with control IC, and peripheral circuitry. If the level of integration of the switching and control circuitry is not high enough, then additional, separate circuits will be required to accommodate all functions. Such additional components raise the overall SMPS cost and not uncommonly reduce reliability.