Negative Input Resistance of Switching Regulators

Even though a switching regulator may produce a constant output voltage at the end of the development phase, often, designers encounter unpleasant effects, such as unwanted oscillations, at the input. So why does the input of the switching regulator tend to oscillate under certain circumstances? In this podcast, we examine "negative" resistance and come to the understanding that the sign is based on a behavior which can be attributed to transients. Download the complete Application Note, ANP008, at www.we-online.com/appnotes or click here. 

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