Use of Phase Delay Analysis for Evaluating Wideband Circuits: An Alternative to Group Delay Analysis

A phase delay analysis is proposed against pursuing a flat group delay response for the design of wideband circuits. While it is believed that a large group delay variation introduces a large data-dependent jitter, this brief reconsiders the effectiveness of the group delay analysis in the evaluation of wideband circuits. Because of its own differentiating nature, the group delay provides a good insight on the delay variation at a vicinity of a certain frequency. However, for certain kind of wideband circuits, the group delay analysis cannot provide a sufficient insight since much of useful information is lost or distorted during the differentiating operation. In this brief, the effectiveness of the phase delay analysis is investigated and comparison with a traditional group delay analysis is presented with a theoretical approach and through a few circuit examples.