High Resolution (Hi-Res) audio is intended to provide high bit depth (typically 24 bits or more) sound quality over the entire band from 20 Hz to 40 KHz (or more). The Redbook CD standard is not sufficient for high sound quality according to recent studies at AES; reportedly there are small but significant perceptible differences in Hi-Res sound. In order to ensure specified performance in a Hi-Res product, the circuitry and PCB design should be considered carefully. An especially small PCB footprint requirement for mobility becomes a tough constraint. This tutorial examins key considerations particularly in terms of circuit design and layout scheme. It includes audio DAC circuit design, Op Amp circuit design, clock scheme, and PCB layout for Hi-Res audio in real applications.
