Preface
senior engineers for applications engineer positions, I found that many of them are still quite
uncomfortable with the very concept of an inductor. Therefore, I think it is a good idea for
every reader, novice or advanced, to read the book in the order of chapters presented,
starting from the very first chapter. Just don’t be caught reading it (by your perception-driven
supervisor!). The temptation of jumping straight into an advanced chapter to “save time”
may just end up slowing things down even more in the long run (besides causing avoidable
bruising of self-confidence for some, along the way). Basic concepts always need to be
brought in at the right time, exemplified, and then firmed up to last a lifetime.
In Chapter 3 I have tried to start at a fairly basic level again, but then ramped up steeply to
provide one of the most detailed step-by-step procedures available for designing off-line
converters and their associated magnetics. This includes the dreaded Proximity Effect
analysis. I have broken up the basic procedure into two separate iterative strategies — one
for foil windings and another for round windings, because their respective optimization
procedures are really very different. There are also generous amounts of curves and plots
thrown in to quickly help the engineer visualize and design the magnetics optimally.
I have included a chapter devoted largely to switching losses in MOSFETs, since this topic
has become increasingly vital as switching frequencies are increased. But it has been
presented with some of the most carefully prepared and detailed graphics probably seen in
related literature — highlighting each phase of the turn-on and turn-off individually.
Common simplifying assumptions have also been made whenever appropriate, and the user
should thereafter have no trouble anymore practicing this rather poorly understood area of
power conversion. There is also some interesting parameterized graphical information
available that can come in handy either for an applications engineer selecting external
MOSFETs, or an IC designer trying to optimize the driver stages of the chip.
The chapter on loop stability is likewise presented from scratch to finish, with very detailed
accompanying graphics. My hope is that for the first time the reader will have easy access to
almost all the equations required for loop compensation. Now, even a novice, can very
quickly get very deep into this area (as I once did).
There are also seven chapters on EMI, starting from the very basics and moving up to a full
mathematical treatment. This is again a topic that has been almost studiously avoided in most
related literature, and yet is needed so badly today. It needs much more elaboration I thought.
To cap it all, there is an “interview-friendly” FAQ, several Mathcad files, and various design
spreadsheets thrown in.
As you can see, the book has been designed to try to live up to its name “A to Z”. Of course
that is never really going to be possible, least of all in an all-encompassing area such as
Power Conversion. But hey, I did give it a shot! The stage is now set. I hope you like
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