Favorite free engineering CAD tools

M

mook Johnson

Jan 1, 1970
0
What are your favorite engineering cad tools avaialble free on the web.

Here are mine:

1) Circuit simultors
Orcad Student version -50 node limit

2) FPGA development tools
none

3) DSP tools (FIR,IIR,FFT, etc)
ScopeFIR

4) PCB CAD packages
Eagle

5) magnetics simulation
Vizimag

6) assembler
Microchip for pic projects.

others?
 
J

Joel Kolstad

Jan 1, 1970
0
mook Johnson said:
What are your favorite engineering cad tools avaialble free on the web.

Here are mine:

1) Circuit simultors
Orcad Student version -50 node limit

LTSpice, no limit whatsoever.
2) FPGA development tools
none

Xilinx WebPack... pretty much covers any of the devices someone doing
development on a shoestring budget is going to be able to afford. :)
Altera's freebies are decent too.
4) PCB CAD packages
Eagle

Good choice.

I left out the items where I don't have a favorite or have little experience.
 
J

Joerg

Jan 1, 1970
0
Hello Mook,
1) Circuit simultors
Orcad Student version -50 node limit

Like Joel I prefer LTSpice. The wiewing window for sim results is IMHO a
bit hokey (x-axis keeps popping back to unusable ranges) but other than
that a fine program.

3) DSP tools (FIR,IIR,FFT, etc)
ScopeFIR

Only FIR filters. I like some old DOS programs better but my favorite
one from Mildenberger talks German so I guess it wouldn't help you. I
wish the more fancy ones would go into wave digital filters and stuff.
But they don't.

If you design a lot of analog filters of the LC kind try Aade's Filter
Design. Not very comfy but fast.

4) PCB CAD packages
Eagle

Very good. Licenses for "real" versions are much more reasonable priced
than other tools. This is one case where the willingness to offer a
useful free version has paid off. I bought it shortly after kicking the
tires on the free version.

5) magnetics simulation
Vizimag

Never tried it but my experience is that this stuff really needs to be
tested in the lab, and very thoroughly.

6) assembler
Microchip for pic projects.

Try the EZ430 kit from TI. Not free but only $20 for USB programmer,
target board and C- plus assembler tool. Can't beat that, I believe. The
IAR basic Kickstart tool is free BTW in case you decide to set up your
own hardware. But you couldn't possibly do that for under $20.



AppCAD from HP. Saves you from whipping out the slide rule, the
calculator and the formula books too often.

Then GCPreview for checking Gerbers. No "see-through" plane patterns but
heck, there is a free version so I won't complain.
 
M

martin griffith

Jan 1, 1970
0
What are your favorite engineering cad tools avaialble free on the web.

Here are mine:

1) Circuit simultors
Orcad Student version -50 node limit

2) FPGA development tools
none

3) DSP tools (FIR,IIR,FFT, etc)
ScopeFIR

4) PCB CAD packages
Eagle

5) magnetics simulation
Vizimag

6) assembler
Microchip for pic projects.

others?
Checkout Reg Edward's site, has a lot of RFfy programs,


martin
 
N

Nico Coesel

Jan 1, 1970
0
Joerg said:
Only FIR filters. I like some old DOS programs better but my favorite
one from Mildenberger talks German so I guess it wouldn't help you. I
wish the more fancy ones would go into wave digital filters and stuff.
But they don't.

Joerg,
Is there any software that allows to get started with WDF filters?
German language is not a problem.
 
J

Joel Kolstad

Jan 1, 1970
0
Joerg said:
Then GCPreview for checking Gerbers. No "see-through" plane patterns but
heck, there is a free version so I won't complain.

OK, if we're going to branch out into other free software tools:

Another good free Gerber previewer is Viewmate by Pentalogix.
Viewing AutoCAD/SolidWorks files: eDrawings
More LC filter design: Elsie (AADE is quite good too -- the two are just a
little different)
Transmission line design: TxLine from AWR
Text editor: EditPad Lite

---Joel
 
J

John Woodgate

Jan 1, 1970
0
dated Mon said:
Like Joel I prefer LTSpice. The wiewing window for sim results is IMHO
a bit hokey (x-axis keeps popping back to unusable ranges)

With the focus on the sim results, click Plot Settings -> Save plot
settings. When you get a new plot with axes you don't like, click Plot
settings -> Reload plot settings. Your preferred axes will be restored.
You can use short-cut keys, of course.
but other than that a fine program.

I just wish there was a comprehensive manual. But it would be a mammoth
task to compile and couldn't be done without the full co-operation of
the author. Many of the most valuable features are undocumented; you
have to learn them from others.
 
J

John Larkin

Jan 1, 1970
0
What are your favorite engineering cad tools avaialble free on the web.

Here are mine:

1) Circuit simultors
Orcad Student version -50 node limit
LTspice


2) FPGA development tools
none

Xilinx WebPak
3) DSP tools (FIR,IIR,FFT, etc)
ScopeFIR

4) PCB CAD packages
Eagle

5) magnetics simulation
Vizimag

6) assembler
Microchip for pic projects.

others?

Appcad

RFSIM99.

FireFox!

John
 
J

Joerg

Jan 1, 1970
0
Hello Nico,
Is there any software that allows to get started with WDF filters?
German language is not a problem.

Yes, the program written by Prof.Mildenberger's group at the
Fachhochschule Wiesbaden in the late 80's. Unfortunately now that he's
retired they dumped his web site. Since the web archive butchered the
file one of the fellows in the German NG repaired the zip file:

I have the older licensed version but later it became free.

There is also a large set of routines from TU Delft but they did the
usual, it's all Matlab and very incompatible with anything else. Even
within Matlab versions. So I could not use that. Had they chosen to
create a "real" stand alone program from it the TU in Delft could have
gained lots of prestige instead of seeing it all go towards that dusty
shelf in the basement.
 
J

Joerg

Jan 1, 1970
0
Hello John,

With the focus on the sim results, click Plot Settings -> Save plot
settings. When you get a new plot with axes you don't like, click Plot
settings -> Reload plot settings. Your preferred axes will be restored.
You can use short-cut keys, of course.

On the last one it croaked even before that. Right click in the plot
window -> manual limits -> entered new right limit. Zilch. Nada. Just
sits on the (useless) default.

I just wish there was a comprehensive manual. But it would be a mammoth
task to compile and couldn't be done without the full co-operation of
the author. Many of the most valuable features are undocumented; you
have to learn them from others.


Yes, but luckily there are some very helpful (and English-speaking)
folks like Helmut Sennewald.
 
J

Joel Kolstad

Jan 1, 1970
0
Joerg said:
There is also a large set of routines from TU Delft but they did the usual,
it's all Matlab and very incompatible with anything else. Even within Matlab
versions. So I could not use that. Had they chosen to create a "real" stand
alone program from it the TU in Delft could have gained lots of prestige
instead of seeing it all go towards that dusty shelf in the basement.

The Mathworks has had a compiler for Matlab (that can create standalone
applications) for years now, although apparently it's one of those things
where often universities have a site license for Matlab itself (and various
toolboxes) but often don't end up licensing the compiler.

---Joel
 
M

Mark Fortune

Jan 1, 1970
0
Joerg said:
Hello Mook,


Like Joel I prefer LTSpice. The wiewing window for sim results is IMHO a
bit hokey (x-axis keeps popping back to unusable ranges) but other than
that a fine program.



Only FIR filters. I like some old DOS programs better but my favorite
one from Mildenberger talks German so I guess it wouldn't help you. I
wish the more fancy ones would go into wave digital filters and stuff.
But they don't.

If you design a lot of analog filters of the LC kind try Aade's Filter
Design. Not very comfy but fast.

I got recommended eagle by someone, tried it, loved it. works on windows
and linux too, so I can use it at home and at the girlfriends place.

Mark
 
J

Joerg

Jan 1, 1970
0
Hello Joel,
The Mathworks has had a compiler for Matlab (that can create standalone
applications) for years now, although apparently it's one of those things
where often universities have a site license for Matlab itself (and various
toolboxes) but often don't end up licensing the compiler.

Well, universities often just don't finish stuff. If they do then they
don't maintain it long term. Even the school where the father of wave
digital filters (Professor Fettweis) taught is a sad example. The center
of competence around him seems to have disintegrated. The result? About
90% of my peers don't have a clue what a wave digital filter is.

This is one of the reasons why I decided to take the plunge and not
pursue a Ph.D. I firmly believe that one must have a strong sense of
long-term commitment and not hop from one interesting project (or job)
to another just because something else looked more glamorous.
 
J

Joerg

Jan 1, 1970
0
Hello Mark,
I got recommended eagle by someone, tried it, loved it. works on windows
and linux too, so I can use it at home and at the girlfriends place.

It is a great SW and much lower in cost than OrCAD. Plus they don't
force-upgrade people by coming out with new versions all the time which
is what finally convinced me to switch from OrCAD to Eagle. Also, they
actually communicate with their customers a lot (what a concept...).

But using Eagle at the girlfriend's place is usually frowned upon (by
the girlfriend).
 
J

Joel Kolstad

Jan 1, 1970
0
Hi Joerg,

Joerg said:
Well, universities often just don't finish stuff. If they do then they don't
maintain it long term.

There's no funding in making "polished products," as far as I can tell... you
get your software/design process/whatever to the point where you can publish a
paper or two -- knowing that it has plenty of quirks/bugs/etc., but all ones
that you know of so that you can work around -- and then it's on to the next
project. :-(
This is one of the reasons why I decided to take the plunge and not pursue a
Ph.D. I firmly believe that one must have a strong sense of long-term
commitment and not hop from one interesting project (or job) to another just
because something else looked more glamorous.

Well... ok, but if commercial entities were had such a strong sense of
long-term commitment, don't you think that software would generally be
somewhat less buggy than it is today? Most companies seem to spend more
effort introducing "glamorous new features" than they do fixing their bugs...

---Joel
 
M

Mark Fortune

Jan 1, 1970
0
Joerg said:
Hello Mark,


It is a great SW and much lower in cost than OrCAD. Plus they don't
force-upgrade people by coming out with new versions all the time which
is what finally convinced me to switch from OrCAD to Eagle. Also, they
actually communicate with their customers a lot (what a concept...).

But using Eagle at the girlfriend's place is usually frowned upon (by
the girlfriend).

It was either that, or haul my workshop round there.
 
J

John Woodgate

Jan 1, 1970
0
dated Mon said:
Yes, but luckily there are some very helpful (and English-speaking)
folks like Helmut Sennewald.

Yes, see my last sentence. It works, but it's not a terribly good
substitute for a manual.
 
J

Joerg

Jan 1, 1970
0
Hello Joel,

There's no funding in making "polished products," as far as I can tell... you
get your software/design process/whatever to the point where you can publish a
paper or two -- knowing that it has plenty of quirks/bugs/etc., but all ones
that you know of so that you can work around -- and then it's on to the next
project. :-(

Sadly, that's their way of thinking and IMHO it's wrong. If they would
collaborate and form competence centers they would gain so much more
status and fame with industry. This in turn would lead to more lucrative
research contracts and that would bring urgently needed money to
universities. But the way it is now, during most industrial projects we
don't even consider involving a university. That could be different. But
only after we see them follow through with their own things.

A great example of doing it right is the Werkzeugmaschinenlabor (WZL) at
RWTH Aachen University (my alma mater). They design and maintain a well
rounded set of CAD tools. Consequently, in my days they were quite flush
with research funds from companies who needed help in mechanical
engineering. I fondly remember the keggers they regularly threw on their
front lawn. Money didn't seem to be an issue there.

I've tried to talk to some about it but it is like kicking an oak tree
so I stopped.
Well... ok, but if commercial entities were had such a strong sense of
long-term commitment, don't you think that software would generally be
somewhat less buggy than it is today? Most companies seem to spend more
effort introducing "glamorous new features" than they do fixing their bugs...

It exists. Look at Cadsoft Eagle. I have yet to have it do a hard crash
and I haven't discovered any tough bug. The only weirdness is that you
sometimes have to unselect and select the printer. Kind of like the
double-clutching on large trucks. Oh well, if that's all I can live with it.

After a while it becomes obvious which companies can achieve quality and
which ones cannot. Just like with cars where there are certain brands or
models I would never buy. This can vary even within companies. For
example, while IMHO much SW from MS is very sub-par there is other SW
such as MS-Works which is and always has been of a solid quality. So I
use that for my book-keeping.
 
J

Joerg

Jan 1, 1970
0
Hello John,

Yes, see my last sentence. It works, but it's not a terribly good
substitute for a manual.


True. In the case of (otherwise often excellent) university software
it's worse. After a few years the folks that were involved have left and
now there is nobody who has much of a clue. Only a handful of people
knew how to fly it. It's like building a complicated piece of test
equipment and not labeling the front panel because you know what all the
buttons do.
 
M

Mr. J D

Jan 1, 1970
0
mook said:
What are your favorite engineering cad tools avaialble free on the web.

Here are mine:

1) Circuit simultors
Orcad Student version -50 node limit

2) FPGA development tools
none

3) DSP tools (FIR,IIR,FFT, etc)
ScopeFIR

4) PCB CAD packages
Eagle

5) magnetics simulation
Vizimag

6) assembler
Microchip for pic projects.

others?

ProgeCAD, Circuit Maker.
 
Top