Using Differential Pairs in Allegro PCB Editor
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Purpose
A differential pair represents a pair of Xnets or Nets routed differentially. The two
members of a differential pair carry the opposite signals. This document covers various
aspects of implementing differential pairs in Allegro PCB Editor.
Audience
This document is intended for users who want to use differential pairs in Allegro PCB
Editor.
Overview
Types of Differential Pairs
Model-defined differential pairs are ones in which the differential pair assignment is
done in the IBIS model.
User-defined differential pairs can be defined in Allegro Design Entry HDL using the
DIFFERENTIAL_PAIR property on nets or created in Constraint Manager. For High-
Speed designs, it is recommended to use model-defined differential pairs.
Differential Pair Terminology
