Audio amplifier power supply design (Part 2):External supplies, inrush current & RF emissions

Part 1 of this article (which is an excerpt from the recently published Audio Power Amplifier Design Handbook) looked at advantages and disadvantages of different power supply technologies as well as the design considerations involved in choosing and evaluating a mains (AC line) transformer.

This part looks at design issues related to locating the AC-line transformer alone, or the complete supply, in a separate chassis external to the load, in a separate chassis, as well as the advantages, and disadvantages doing so. It considers not only the obvious physical and cabling issues, but also inrush currents and their suppression, fusing and rectification, and RF emissions.

The article, which originally appeared at EE Times-Europe (Power Management), is presented as a pdf file (no registration required). To read it, click here.

About the author
Douglas Self is a senior designer of high-end audio amplifiers and contributor to Electronics World magazine.