As system designers are called upon to create products with more features while maintaining a flat or decreasing product cost, advancements in device technology must be considered. To produce integrated circuits (IC) with increased functionality at a reasonable cost, IC manufacturers need to reduce overall silicon areas. However, the functional and cost benefits associated with smaller areas can not be achieved without some system design trade-offs. These smaller geometry ICs typically have a maximum voltage rating of 3.0V or below, instead of the existing maximum 5.0V rating.

This application note is intended to provide the system designer with an overview of different options that could be used to down-convert an existing 5.0V system rail to a regulated 3.0V. Approaches discussed are the Low Dropout Regulator (LDO), charge pump, and buck switch mode converter.