TABLE OF CONTENTS This section serves to highlight and summarize the gamut of key topology-related design issues that should be kept in mind when actually designing converters (or when appearing for a job interview!).
Question 1: For a given input voltage, what output voltages can we get in principle, using only basic inductor-based topologies (buck, boost, and buck-boost)?
Answer: The buck is a step-down topology (V O < V IN), the boost only steps-up (V O > V IN), and the buck-boost can be used to either step-up or step-down (V O < V IN, V O > V IN). Note that here we are referring only to the magnitudes of the input and output voltages involved. So we should keep in mind that the buck-boost also inverts the polarity of the input voltage.
Question 2: What is the difference between a topology and a configuration?
Answer: We know that, for example, a 'down-conversion' of 15 V input to a 5 V output is possible using a buck topology. But what we are referring to here is actually a "positive-to-positive" buck configuration, or simply, a "positive buck." If we want to convert -15 V to -5 V, we need a "negative-to-negative" buck configuration, or simply, a "negative buck." We see that a topology is itself fundamental (e.g. the buck) but it can be implemented in more than one way, and these...
