Download Layout SmartRoute User's Guide

Chapter 1
About SmartRoute
Autorouters have two primary objectives: to route boards to 100% completion and to
route boards quickly. SmartRoute adds a third objective—quality of routing.
Historically, professional board designers have complained that autorouted boards
do not provide the same quality as manually routed boards. The side effects of
autorouting can include too many vias, tracks that wander, vertical layers with too
many horizontal segments and vice versa, unevenly spaced tracks, and more.
The most common complaint, however, is that autorouters usually route using an
X,Y orthogonal strategy. Experienced board designers instinctively route using
diagonals. Diagonal routing is more aesthetically pleasing and allows for more track
segments to be placed in an area. Consequently, the probability of finishing a more
difficult board is increased with diagonal routing.
This chapter examines the new technologies and time-proven methods that
SmartRoute uses to tackle autorouting quality issues.
Neural networks
A neural network is a subset of artificial intelligence. SmartRoute uses a neural
network for routing intelligence, and time and completion projection. It is among the
first CAD software products to employ artificial intelligence.
A neural network analyzes problems for which there is no explicit solution. Instead,
there may be a variety of solutions, some better than others. Consider an analogy.
There are a variety of ways a board can be routed, some of which are better than
others. The designer selects the best solution, considering all the options and
possible outcomes. This is also the function of the neural network and the other
neural utilities in SmartRoute: to provide intelligence that will result in the “best”
routing.
OrCAD Layout SmartRoute User’s Guide
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