高效率功能电源转换

　　简介

　　高效率往往是电力的主要目标便携式计算机和手持设备中的供应品。高效转换器是必要的，在这些应用程序减少输入源（电池等）的功率损耗和热量积聚在电源组件，允许更小，更轻，寿命更长的系统。电源转换效率必须在90%范围内才能满足这些目标。本应用笔记功能电源满足这些设计要求并达到的电路高效率在较宽的工作范围。

　　The recent development of the LTC® 1142， LTC1143， LTC1147， LTC1148， and LTC1149 makes ultra-high efficiency conversion possible. In addition， the LTC1148， LTC1149， and LTC1142 are synchronous switching regulators， achieving high efficiency conversion at output currents in excess of 10A. These controllers feature a current mode architecture that has automatic Burst ModeTM operation at low currents. This technology makes 90% efficiencies possible at output currents as low as 10mA， maximizing battery life while a product is in sleep or standby mode.

　　These ultra-high efficiency converters also implement constant off-time architecture， fully synchronous switching and low dropout regulation. All these features make this series of converters a really excellent choice for a vast variety of applications.

　　Achieving high efficiency is one of the primary goals of switching regulator design. Every application circuit shown in this note includes detailed efficiency graphs. Almost all of the magnetic parts used in the circuits are standard products， available off-the-shelf from various manufacturers.