Controlling Impedances When Nets Branch Out
Contributor:
Douglas Brooks, President
UltraCAD Design, Inc.
Format: PDF Document
It is not uncommon for a driver to drive numerous receivers. In some designs it is impractical, or undesirable, to drive every receiver from a single trace segment. In such cases it is common to design a trace that branches out into two or more branches, each serving a select number of receivers. The question then becomes where to place the branch point. Improper placement of the branch point can have serious implications from an impedance discontinuity standpoint, resulting in reflections that can have signal integrity consequences. This paper describes several ways to deal with the branching problem in designs if they come up.