Design
http://www.smartgroup.org/
The SMART Group download page provides a wide range of technical articles related to the assembly process and common process defects.
http://www.pcbstandards.com/
Useful chart comprehensively illustrating and explaining all aspects of pcb manufacture. Site index for vast collection of free downloadable data relevant to pcb design, e.g. pad patterns, current capacity calculators, impedance calculators, flex circuit design advice, etc.
http://www.ipc.org/
Large amount of free downloadable CAD information. eg. smd land patterns, impedance calculators, IPC Standards, etc.
http://www.allflexinc.com/guid.shtml
A comprehensive downloadable flexible circuit design guide.
http://www.yelo.co.uk/area3/pcbtester.htm
Guidelines for Testing PCB's. The following are guidelines to assist companies who are laying out PCBs which they wish to test using bed of nails, both in-circuit and functionally.
http://www.emclab.umr.edu/pcbtlc2/index.html
PCB track impedance calculator which calculates the characteristic impedance and per-unit-length parameters of typical printed circuit board track geometries.
http://www.intel.com/design/packtech/ch_14.pdf
Fully comprehensive treatise on BGA's, from foot-prints to re-work.
http://www.pcblibraries.com/resources/
Free downloadable pcb design checklists, advice, documentation, & libraries amongst a wide range of useful information for novice CAD designers.
Lead-free
http://www.npl.co.uk/ei/news/faqs.html
The most frequently asked questions and answers on lead-free soldering and components. Highly recommended.
http://www.environment-agency.gov.uk/netregs/legislation/
Gives details on the Restriction of Hazardous Substances in Electrical and Electronic Equipment (ROHS) Directive (2002/95/EC)
It effects manufacturers, sellers, distributors and recyclers of electrical and electronic equipment containing lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls or polybrominated diphenyl ethers. This Directive covers the same scope as the Directive on waste electrical and electronic equipment (WEEE) except for medical devices and monitoring and control instruments. It also applies to electric light bulbs and light fittings in households.
http://www.npl.co.uk/ei/research/leadfree.html
National Physics Laboratory: reports on the scientific programme on measuring and modelling the materials properties impact on solder joint reliability.
http://www.envirowise.gov.uk/
Envirowise offers UK businesses free, independent, confidential advice and support on practical ways to increase profits, minimise waste and reduce environmental impact. It explains the effects of the Directive on waste electrical and electronic equipment (WEEE).
Materials
http://pcbtrain.co.uk/www.isola-group.com
This is the site of Isola, a major laminate supplier with the technical specifications for a wide variety of laminates. e.g. CEM1, FR3, FR4, FR5, BT resin, Polyimide, Cyanate ester, FR5 aramide.
http://www.rogerscorporation.com/ Rogers are a major manufacturer of high frequency laminates. This site contains technical specifications for PTFE laminates, and other materials. There is also a downloadable impedance calculator.
http://www2.dupont.com/Pyralux/en_US/index.html
Information about flexible printed circuit materials supplied by Du Pont
http://www.taconic-add.com/en--products.php
RF, microwave, & high-speed digital laminates for all applications from Taconic
http://www.holders.co.uk/index.htm
Distributors of Arlon laminate for microwave applications and a wide variety of related materials
http://www.lamargroup.co.uk/
Distributors of Nelco, Panasonic and Shanghai NanYa Laminates including microwave, Polyimide and BT laminates.
Software
http://www.graphicode.com/
Download the GC-Prevue gerber viewer from this site. It is highly recommended and free of charge.
http://www.numberone.com/links.htm
The site of the authors of EasyPC software. You can download demo software. It also contains links for downloadable component data sheets.
http://www.polarinstruments.com/
This site mostly deals with controlled impedance issues. It offers free downloads of useful software such as a 2D Field solving Impedance design system supporting 39 controlled impedance structures. Other items are freeware PCB track resistance calculator, gerber files for a typical impedance test coupon, graphical pcb test and repair software which replaces schematics and reads most popular CAD formats plus IPC.
Standards
http://www.ipc.org/
This site has the IPC Standards.
http://www.ul-europe.com/
The UL Library helps with standards, certification issues, technical requirements, and how they are applied. It also has downloadable marks.
http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/index.htm
The Underwriters Laboratory database of approvals is an essential tool if you are selling into the US. Searches can be made by a company name, UL file number, or keyword.
PCB CAD Design Software
http://iut-tice.ujf-grenoble.fr/kicad/index.html
Kicad is a CAD layout programme for the creation of schematic diagrams and printed circuit boards up to 16 layers. The software is free and downloadable with no restrictions and runs on Windows XP. Gerber data can be viewed and Gerber files for photoplotters, drilling files and component location files can be output for manufacturing. Documentation is multi-lingual. The software is widely used and constantly updated. It is designed and written by Jean-Pierre Charras, a researcher at LIS (Laboratoire des Images et des Signaux) and a teacher in IUT de Saint Martin d'Hères.(France), in the field of electrical engineering and image processing. Kicad was highly recommended by an Elector Magazine review article in July-August 2007.
BOARDMAKER
CADSTAR
EAGLE
CIRCAD
CIRCUIT CREATOR
DESIGN WORKS
EASY-PC
E-CAD
EDWin
ELECTRONICS WORKBENCH
LAYOUT
MENTOR
ORCAD
P-CAD 2004
PCB ASSISTANT
PCB DESIGNER
PCB ELEGANCE
POWERPCB
PROTEL/ALTIUM DESIGNER
PROTEUS
QCAD
RANGER
Seetrax XL Designer Lite Software Download: The Lite version of the Seetrax XL Designer software is a fully functional version of the full software but limited to designs with a maximum of: 30 parts & 50 nets. It is not time-limited. The downloaded file is a self-contained, licensed copy of the software for new installations. It can also be used to update an existing installation of the Seetrax XL Designer Lite (or Demo) software.
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