文档介绍：Source: Switching Power Supply Design
Part
1
Topologies
Downloaded from Digital Engineering Library @ McGraw-Hill ()
Copyright © 2004 The McGraw-panies. All rights reserved.
Any use is subject to the Terms of Use as given at the website.
Topologies
Downloaded from Digital Engineering Library @ McGraw-Hill ()
Copyright © 2004 The McGraw-panies. All rights reserved.
Any use is subject to the Terms of Use as given at the website.
Source: Switching Power Supply Design
Chapter
1
Fundamental Switching
Regulators—Buck, Boost, and
Inverter Topologies
Introduction
There are about 14 basic topologies (basic block diagrams) commonly
used to implement a switching power supply. Each topology has unique
properties which make it best suited for certain applications.
Some are best used for AC/DC off-line converters at low (<200 W)
output power, some at higher output power. Some are a better choice
for high AC input voltages (Ն220 V AC); some are better for an AC
input of 120 V or less. Some have advantages for higher DC output
voltages (> ~ 200 V) or in applications where there are more than four
or five different output voltages. Some have a lower parts count than do
others for the same output power or offer a better tradeoff in parts
count versus reliability. Lesser input or output ripple and noise is a
frequent factor in a topology selection.
Similarly, some topologies are better used for DC/DC converters—
again with high and low output power, high or low output voltages, and
minimum parts count as significant selection criteria. Further, some
topologies have inherent design drawbacks which require additional
circuitry or plex circuitry, pletely analyzable in
various worst-case situations.
Thus to make the best choice of a topology, it is essential to be
familiar with the merits, drawbacks, and areas of usage of all
topologies. A poor choice of a topology can doom a new power supply
design at the very