TABLE OF CONTENTS Non-isolated switching power supplies are those supplies where the input and output share a common ground and other signals. They can also sometimes propagate failures to other portions of the system, if not designed properly.
They can only be used when the input power source is considered "safe" to the user. This is where the input voltage is less than 42 VDC. Any input voltage greater than 42 VDC is considered "hazardous" to the user and requires dielectric isolation between the input and output (see Chapter 6).
One finds this type of switching power supply in portable equipment and low voltage printed circuit boards. There are many design aids available from the semiconductor suppliers in the market today.
Ray Mack uses very straightforward design flows to illustrate the design of several non-isolated switching converters, based upon ICs from Linear Technology.
Marty Brown
In this chapter, we will look at detailed designs of non-isolated converters. The applications include remote regulation for line-operated systems or power management in battery-operated systems. I find at least one new application or new device suitable for a non-isolated circuit every week in the trade journals. The applications have exploded during the past five years and show no signs of slowing. The trend is toward ever smaller, more efficient, and more specialized controllers. The designs we will look at here will give general design methodology as part of the specific designs.
Engineers seem enamored of creating new jargon and acronyms or initials. The new...
