Aims

"PCB Design" is a task based multimedia course which provides the students with a systematic presentation of high performance printed circuit/wiring board (PCB/PWB) design and complex characterization of PCB structures and offers, based on numerous figures, formulas and examples, a practical approach on design of printed circuits.

4) Understanding advanced topics in PCB design based on electromagnetic compatibility, signal integrity, and related issues.

5) Understanding PCB post-processing and the interface designer - manufacturer.

Contents

The course is destined to cover both theoretical aspects related to PCB design and practical aspects for computer aided design of PCB. It is based on two main tasks. The first one is destined to the design of an analog PCB electronic module and the second one to the design of a digital PCB module. In order to understand the fundamental topics of PCB design, the student can download a general tutorial from the address:

http://www.ipci-project.com/files/tutorials/images/16/MMPCB_tutorial-total.zip

This tutorial is divided in two main areas: "Fundamentals of PCB design" and "CAD for PCB". The eight modules, four destined to "fundamentals" and four to "CAD" cover a large area of topics, from basics of PCB design to signal integrity analysis, simulation, design techniques and CAE-CAD tools. Additionally, the student shall find a multimedia glossary of terms, animated design flows and practical tasks, various types of tests for creating a solid background for future engineering activity in PCB field. "Fundamentals of PCB design" covers theoretical fundamentals of printed circuit structures design. It starts with basics of PCB, structures and materials. The next chapters are oriented to an introduction in time, frequency and distance, PCB parasitics, lumped/distributed circuits, current capacity of traces, transmission lines, characteristic impedance control, and termination technique. In addition, signal integrity analysis topics, as relative permittivity/effective permittivity, reflections, and crosstalk and EMI are discussed in depth. "CAD for PCB" covers the basics of CAD-Computer Aided Design in development of PCB. The course presents techniques and methods for placement, routing, and optimizing the PCB. The last part is destined to CAD-CAM systems for post-processing, Gerber/Excellon files generation, and interfacing designer and fabricator. The CAD area is based on OrCAD and supports all the phases of the design process: design creation, placement of footprints, routing of traces, post-processing, and inter-tool communication.

The course is based on OrCAD/Windows design environment due to its high quality features in CAD conception of electronic projects and powerful printed Circuit Board (PCB) design of on-board metallic interconnection structures. The environment supports all the phases of CAE-CAD-CAM design process using the internal native blocks of OrCAD or external blocks which are basically stand-alone programs and are provided by other professional companies as Wise (Gerbtool), Quantic (Omega Plus) and Cadopia (IntelliCAD).

(source:www.vutrax.co.uk)

The PCB design flow allows the following main activities: SCM design creation, SCM post-processing, placement of components, routing of tracks, optimizing the final layout, PCB post-processing, and Inter-tool communication (for various links between blocks).

Below is offered a "zip" archive of a Flash presentation that emphasize the basic design flow of a PCB electronic module.

http://www.ipci-project.com/files/tutorials/images/16/CAE-CAD-CAM_Practice.zip

Using the schematic block "OrCAD Capture" the designer can create the Layout-compatible netlist that includes preset design rules to guide logical placement and routing, depending on the type of the electronic project (analog, digital, mixed, high density, high speed). SCM gives the ability to specify critical design rules at the schematic level (component locations, spacings, grouping of components, widths of signal and reference tracks, routing layers, etc.) and bring them into Layout inside the netlist SCM-PCB transfer file. Layout's Auto ECO (engineering change order) procedure from Layout updates the PCB design without destroying a finished layout work.

In OrCAD the user can perform manual placement or interactive/automatic placement utilities of components, having a total control of the component placement process. During auto-placement, Layout can use the powerful 'shove' capability to move components out of your way automatically while keeping the guidelines of various design rules (DRC).

The same for routing, the user can perform manual routing or interactive/automatic routing of conductive PCB tracks. Using manual route it is possible to guide the routing process based on specific requirements (track by track). In interactive routing, the designer still control the routing of individual tracks, but can take advantage of Layout's automatic routing motors, such as 'push & shove' capability (it allows to move pre-routed tracks in order to create space for the current track). The auto-router can route singular tracks, selected areas inside the layout, groups interconnections (nets), or the entire printed circuit board.

At the end of PCB stage all of output settings are stored in a spreadsheet that the user can recall and revise. It is possible to give layer-by-layer instructions for writing Gerber (standard and extended), Excellon, DXF and other formats of files, as well as hardcopies in order to generate the technical documentation. A large range of of reports (BOM, DRC, drill lists, parts orders, ECOs, fabrication & assembly drawings, pick-and-place info, etc.) can be easily produced.

OrCAD has the capability to communicate interactively inside its environment (Capture & Layout) using the feature called 'INTERTOOL communication' to communicate updated SCM information to Layout, at any stage of the design process and to 'BACK-ANNOTATE' PCB design data to Capture. Intertool communication supports cross-probing to facilitate design analysis (selecting a signal or part in Capture/Layout, the corresponding signal or part is automatically highlighted in the other block).

- Passive Electronic Components and Structures
- Active Electronic Components and Devices
- Analog and Digital Integrated Circuits
- Basics of Electronic Packaging
- Basics of PCB