Digital-to-analog converter for bipolar signals.

摘要

In a digital-to-analog converter for bipolar signals all the bits change when the signals pass through the zero level. This result is a poor signal-to-noise ratio owing the small signal and the larger noise contribution of the switching transients. The invention is to add a digital number to or subtract it from the digital input signal as an offset. As a result of this, the point at which all the bits change is shifted towards a higher amplitude, which improves the signal-to-noise ratio and the distortion behaviour in the case of digital audio signals.