Overview

In Chap. 2 the basic PCB design flow was demonstrated starting from schematic entry with Capture to board routing with Layout, but no attention was given to board design issues such as component placement and spacing rules, layer stack-up, or trace routing and spacing rules.

Design examples will be used in this chapter to illustrate the various PCB design considerations described in Chaps. 5 and 6 and how to use the Layout tools to accomplish the design goals. The part count in each example is kept to a minimum (all designs have fewer than 10 parts and 14 pins/part) so as not to be cumbersome and not to distract the reader from understanding how to route and set up layers and so that the Demo version can be used. In-depth discussion on PCB design manufacturability is covered in Chap. 5 and signal integrity and routing are covered in Chap. 6.

The following examples use parts that may not be included with your version of OrCAD. You can make the parts yourself using the procedures discussed in the previous chapters, or you can copy the parts and footprints provided in the example libraries located on the CD-ROM included with the book.

The first example is a simple analog design using a single op-amp. The design shows how to set up multiple plane layers for positive and negative power supplies and ground. The design also demonstrates several key concepts in Capture, such as how to connect global nets, how to...