Introduction
xiii
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 assign foot-
prints, how to perform design rule checks, how to use the Capture part librar-
ies, how to generate a bill of materials (BOM), and how to use the BOM as an
aid in the design process in Capture and PCB Editor. The design also shows
how to perform important tasks in PCB Editor, such as how to set up a board
outline, place parts, and modify padstacks. Intertool communication (such
as annotation and back annotation) between Capture and PCB Editor is also
demonstrated. The second design is a mixed digital/analog circuit. In addition
to the tasks demonstrated in the first example, the design also demonstrates
how to set up and use split planes to isolate analog and digital power supplies
and grounds. Other tasks include using copper areas on routing layers to make
partial ground planes, setting up split power and ground planes, and defining
anticopper areas on plane and routing layers. The third example uses the same
mixed digital/analog circuit from the second example but demonstrates how
to use multiple-page schematics and off-page connectors to add PSpice sim-
ulations to a Capture project used for PCB layout, all within a single project
design. It also demonstrates how to construct multiple, separated power and
ground planes and a shield plane to completely isolate analog from digital cir-
cuitry. The use of guard rings and guard traces is also demonstrated.
The fourth example is a high-speed digital design, which demonstrates how to
design transmission lines, stitch multilayer ground planes, perform pin/gate
swapping, place moated ground areas for clock circuitry, and design a heat
spreader.
The last part of Chapter 9 includes a short discussion about the differences
between using negative and positive planes in PCB design.
Chapter 10 describes taking the PCB design from the CAD stage through fabri-
cation. A simple design example shows how to produce the artwork (Gerber)
files for a PCB design. PCB Editor is then used to review the artwork files before
they are sent to a manufacturer. PCB Editor is also used to generate a drawing
(dfx) file that can be opened and edited with many drawing applications, so
they can be 3-D modeled to review form, fit, and function. The chapter also
describes how to create a custom report that can be used for pick and place
machines during the assembly process.
At the Web site for this book, www.elsevierdirect.com/companions/
9780750689717, you should find supplementary content including the demo
version of the software and the design files used in writing this book. The
design files include the design flow example from Chapter 2, the Capture parts
from Chapter 7, the footprint and padstack symbols from Chapter 8, the board
layout files from Chapter 9, and the manufacturing files from Chapter 10. The
newest version of the demo can also be obtained from the cadence Web site.
During the development of this text, the author received technical assistance
from Cadence, so many of the procedures and concepts were written from les-
sons learned and feedback from Cadence. While every effort has been made to
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