[Cryptech Tech] design software

[Jacob]

I have followed through the recent discussion of design SW choice (we 
had a similar discussion in the past), and thought to add my view:

1. There are different tiers of Schematic / PCB layout systems:
The most capable ones for Layout are the Cadence's Allegro and Mentor's 
Expedition. For Schematic work is Mentor's DxDesigner and possibly some 
Cadence stuff.
Second tier for Layout are Mentor's PADS and Altium. Schematics is 
Cadence's OrCAD and possibly some Altium stuff or PADS Logic.
Third tier and below are the rest of the programs out there.

Disclaimer1: there may be some recent new entries positioned at 
different tiers that I am not aware of.
Zuken has some good stuff, but historically was strong at analog design. 
I don't know much about them. They are rare though in the westerm 
hemisphere.
Disclaimer2: I am totally unfamiliar with KiCAD. It may be a powerful 
system, but I know that it lacks interfaces to required supportive 
systems e.g. SI tools.

2. The 1st/2nd tier programs have features that the third tier programs 
do not. Just doing the check list (and Altium/Protel was an ace in this 
regard) does not guarantee that the required feature works as desired.

3. It is extremely difficult to separate a man from his tried and true 
tool-of-the-trade.
It takes years of experience with a complex tool to feel knowledgeable 
and comfortable with it.
There is quite a bit of weight for selecting the best tool for the job, 
regardless if it is commercial closed-source or not. But you take 
whatever you can afford, and if you can only afford volunteers, you take 
what they have.

4. There are conversion utilities to convert from one format to another. 
Some converters are integrated within the specific target system, some 
are open source, some are commercial.
There are always issues when converting, which may require a few days to 
iron out, but connectivity is usually straightforward (unless done by 
complex copper areas) so you can support relevant auditing by comparing 
the net list generated from the source to that of the target layout.

5. I totally agree with Peter on auditing: nobody will do that. How many 
did audit Truecrypt? Even the "opencryptaudit" organization, after 
raising some good money, did only a partial job. Besides, let's first 
see the users fully audit the software, which is 90+% of the whole 
project, before going after a funny component or a rogue copper trace.
However, users will feel fuzzy and warm to know that if they so desire, 
they can convert the schematic/layout and audit.

6. I myself use PADS (many years of experience). The database is fully 
documented ASCII. Allegro, Expedition and Altium can read it. A company 
in Europe sells a bi-dir converter from/to Eagle at less than 1KEuro or 
so. I personally may do designs also in Allegro/Expedition, but not with 
any other system.