Electronics Forum / CAD / March 2008

On Mar 13, 2:02 pm, a7yvm109gf...@netzero.com wrote:
"Then I guess that means that no matter how good the lower-
end (i.e., affordable) PCB layout software is, a professional layout
engineer cannot really use anything other than PADS or Protel, since
they are the established current standards in the USA."

If by "professional layout engineer" you mean someone who's independently
doing PCB layout on contract (rather than being a regular employee within a
company), you're probably right.

"A real shame
too, since these high-end packages cost so darn much!"

Some of the companies will provide a discount for contractors since they
realize that the regular prices are a bit much if you're PCB layout isn't the
only service you provide.  However, it's always the initial purchase price
that's a killer -- even the high-end packages usually have maintenance fees
that are "only" somewhere in the "mid four-digits."  If you're doing contract
work and the company expects you to be providing the CAD license, this isn't
too huge of a "cost of doing business."

Many low-end packages will export a PADS and, sometimes, Protel netlist (as
these are relatively easy features to provide).  Importing is a lot harder
because importing a netlist without being able to import a footprint library
isn't generally useful, and importing footprint libraries is often a difficult
feature to provide (i.e., it takes a lot of time... especially with newer CAD
programs where pads can be relatively complex shapes).

---Joel

Some of these vendors make changes to file formats that are
designed to break the importing capability of competitive
products.  What makes this especially damaging to a design
engineer is the fact that some boards still in production
may have been created years earlier -- sometimes with a
mechanical CAD package.

The long term answer is to switch to an open source electronic
CAD system as soon as one that meets your needs is available.
The kicker is that each of has unique needs.  One person might
require nothing less that on of the high end EDA products that
cost thousands and thousands of dollars per seat, while another
might do fine with a low-end product.  If they meet your needs,
open-source EDA tools such as Kicad or gEDA will avoid many of
the above mentioned problems.

References:
http://archives.seul.org/geda/user/Aug-2005/msg00023.html
http://www.eedesign.com/resources/opensourcelinks.html
http://www.eetimes.com/news/design/resources/opensourcelinks.html
http://www.deepchip.com/edajumpzone.html

Pulsonix will export schematics in ORCAD format.  Well, at least it tries
to... there are numerous glitches in the process, but in some cases it's
probably still faster than re-drawing the schematic by hand in ORCAD.
Pulsonix says they're not really actively developing the feature (i.e.,
removing bugs), so my suspicion is that someone paid them to add the feature
and either is happy with the current performance or else ran out of
time/interest/money.

Agreed.  Importing data in other format is fraught with difficulties as
well... some companies, such as Mentor Graphics, seem to make various minor
changes to their netlist formats almost annually for what can either be seen
as (1) having a bunch of borderline-competent programmers around or (2)
wanting to break everyone's import routines as a means of gaining a
"competitive" edge.  Interestingly, there's the exact same problem in the
mechanical CAD field.  AutoCAD, of course, become so much of a standard that
there's a funded consortium (http://www.opendesign.com/) that builds libraries
to do nothing but read and write DXF/DXG files!  The consortium was so
successful that Autodesk actually began ENCRYPTING users' designs files (!)
(...encryption that was shortly broken by the Open Design Alliance guys),
which has got to be about the most customer-unfriendly thing a software
company could ever do, in my view.

Although I wouldn't necessarily put it past, say, Microsoft to introduce some
new Office that used an undocumented encryption format to prevent, e.g.,
OpenOffice from reading it and try to pass it off as a security improvement
meant to help customers.

---Joel