Printed Circuit Boards

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layers has tips for finding how many layers you need, and what to put on each layer (micro ball-grid arrays ...)

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See: Electronic Construction - Tips, Tricks, Gens, Traps, and Snares

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bibliography for layout editor:

(see also the more general bibliography for schematic editor )

If you're using a PWB layout editor, you might want to look at these items: "Design for Manufacturing"

PCB Trace Width Calculator by Brad Suppanz fit to IPC-D-275 http://www.geocities.com/CapeCanaveral/Lab/9643/TraceWidth.htm
IPC-D-275D Design standard for rigid Printed Boards and rigid Printed Board Assemblies http://www.ipc.org
Murrietta Circuits Design Layout Standards http://www.murrietta.com/mc-ls.htm
_High-Speed Digital Design : A Handbook of Black Magic_ by Dr. Howard Johnson, and Martin Graham. http://www1.fatbrain.com/asp/bookinfo/bookinfo.asp?theisbn=0133957241 "I suggest this book to anyone that is designing high speed digital boards. In fact, his book is refered to by the PCISIG group many times. PCISIG has very specific requirements for the design of PCI cards. ... Tons of good downloadable formulae for Mathcad on his site too." -- recc. Wamnet "my first choice ... H. Johnson's archived newsletters [ on http://www.sigcon.com/ ] are better than his book in some ways (real life examples vs more text book approach)." -- recc. Greg Erker on 2000-07-14
_Digital Design for Interference Specifications_ (2nd Edition) by David Terrell and R. Kenneth Keenan. "A close second choice" -- recc. Greg Erker on 2000-07-14
_EMC and the Printed Circuit Board_ by Mark I. Montrose. "my third choice" -- recc. Greg Erker on 2000-07-14
_High Speed PCB Design_ by Lee W. Ritchey and James C. Blankenhorn. "better than nothing" -- recc. Greg Erker on 2000-07-14
_Surface-Mount Technology for PC Boards_ by James K. Hollomon, Jr. (1995)
_Printed Circuit Board Basics_ by Michael Flatt ``has some interesting info, although it's very manufacturing-oriented.'' --"Dwight Harm" on 2001-04-07

[Any other must-have, highly recommended books ?]

general PWB design news and mailing lists

For general PWB design questions, check out the mailing lists available at http://www.ipc.org/html/forum.htm .
Consider joining the mailing list dedicated to the specific tools you are using. If you use Protel, joing the Protel mailing list app/protel_about.htm#news .

[FIXME: point to other mailing list and Usenet newsgroups: ... PIClist with the [EE] topic, comp.arch.embedded, ... ]

advice on learning PCB design

[FIXME: merge with bibliography ?] [FIXME: split into seperate CAD-independent FAQ ?]

consider joining a pwb design mailing list .

"The Printed Circuit Design Resource" http://home.fda.net/bbrooks/pca/pca.htm
```
From: Brooks Bill
Sent: Wednesday, August 02, 2000 11:10 AM
Subject: RE: [PROTEL EDA USERS]: Advice on Learning PCB Design
```
Andy... I am trying to put together a website to address this very issue... It's still under construction but you may find some of what you are looking for under 'education' in the Navigation menu on the left side of the page. Here's the link - http://home.fda.net/bbrooks/pca/pca.htm
I will be adding more to it as time goes on... make sure to check back often.
```
Bill Brooks
Senior PCB Designer 
Zoneworx, Inc.
40925 County Center Drive, STE 200
Temecula, CA 92591
 http://www.zoneworx.com
Tel: (909) 296-1226 x 1037
Co-Director / Education Officer / Webmaster
for the San Diego Chapter of the IPC Designers Council
http://www.ipc.org/SanDiego/
```
http://www.pcbstandards.com/ ``Dedicated to the free exchange of data in a constantly evolving environment.''. Has lots of footprint libraries. (Sometimes footprints are called ``decals'' or ``land patterns''). Lists ``the wind river standards'' for component footprints. Also has tools for calculating stripline trace impedance, current handling trace widths, checklists used in the design process, ``Clutter Control'', and online discussion forums.
Copper Connection http://www.copperconnection.org/ "you might find this useful" -- Melvin Hart Burk Jr., PASCO scientific http://www.pasco.com "Mary Snugden [at Copper Connection] is an excellent instructor, funny too!)" -- Brad Velander Norsat International Inc. www.norsat.com
[FIXME: obsolete ? The Copper Connection, Inc. http://www.copperconn.com/ "We teach several high-tech software applications used in computer aided engineering, design and manufacturing. We specialize in AutoCAD , MS Office, and PCB Design." ]
The PCB Design conferences "not the best for newbies ... [but] ... a lot of information from the sum total of your seminars at the conference. ... a cheap alternative to taking many individual courses offered at differing times in differing locales. The number one benefit I have found at the conference is the acquaintances that you can make with designers near and far ... you also get to make contacts with tool suppliers, fabricators and design bureaus." -- Brad Velander Norsat International Inc. www.norsat.com
SMT+ http://www.smtplus.com/ "I would also recommend highly "SMT+" " -- Brad Velander Norsat International Inc. www.norsat.com

A few general PWB design tips (general design):

If you have multiple ``ground'' nets, (e.g. GND, AGND, DGND, EGND, CGND, SGND, etc.), consider this idea:
Dave Lewis suggests on 2001-05-23 06:10:46 PM
Net Names on all Power Symbols
Use the "little arrow thingy" power object, enter the net name as required, and then place it upside down. Viola! It looks like a little ground symbol with the net name displayed. My printouts are legible and I really like being able to see the assigned net name for the ground. I have since given up on using all those other cute symbols (ie. the ones that don't display the net name) mostly because they can be assigned to ANY net so you really don't know for sure at a glance. For bias nets I like the bar do-dad. - Dave Lewis
``Do not split the ground plane. Use one solid ground plane under both analog and digital sections of the board.'' -- Ott, in article ``partitioning and layout of a mixed signal pcb'' article by Henry W. Ott (EMI consultant) in _printed circuit design_ magazine (june 2001) http://www.pcdmag.com/db_area/archives/2001/06/0106_1.html [FIXME: offline. is there a copy of this somewhere else ? Or a more recent article on this topic ? "Grounding of Mixed Signal PCBs" by Henry W. Ott 2000 http://www.hottconsultants.com/techtips/split-gnd-plane.html repeats this advice. ]
Henry Ott Consultants http://www.hottconsultants.com/

in it he basically makes the case that split planes are generally a bad thing
their best use he says is to correct a badly laid out board after the fact and also in some cases they are needed for safety isolation
but as to localizing noise (preventing polution of low level signals) and minimizing EMI nothing beats a *properly laid out* (i.e. 'routed/placed') board with a single ground plane possessing a single net
-- recc. Dennis Saputelli 2001-06-09
Oztronics Tip of the Month http://joj.home.texas.net/tipofmth.html
Brad Velander on 2001-04-17 mentioned that http://www.merix.com/main_res.html has some info on gold plating and DFM.
V Scoring score depth

Assuming you are going to do a manual breakaway of the boards, I recommend a final web thickness of 0.012" with 30 degree cutters on FR4. If you are using mechanical/machine separation you can go slightly thicker. The thin web thickness allows for easy, manual breakaway with minimal potential damage to the components and the solder joints.
-- Ed Valentine on 2001-08-07 Electronics Manufacturing Solutions http://www.ems-consulting.com

Please take note that your respondents have discussed the material "remaining" after the scoring process. Your drawing should not indicate a depth requirement, but the amount of material remaining.
Gary Ferrari on 2001-08-07
Pocket Guide to Excellent V-Scoring http://www.accusystemscorp.com/FAQ's%20-%20Index.htm ``useful'' -- recc. Bill Brooks 2001-08-07 PCB Design Engineer http://home.fda.net/bbrooks/pca/pca.htm
The Printed Circuit Design Resource Guide by Bill Brooks http://home.fda.net/bbrooks/pca/pca.htm