0.1pF three-terminal capacitor

[Fred Bloggs]

Fred Bloggs wrote...



Testing the posting just now - it downloads and displays fine.
But it's a two-part post, because of the binary file's length.
Perhaps your viewing program didn't successfully download the
second part to complete the file? Would you like me to repost
it to see if that fixes the problem?

I'm think you'd be interested in the article.

If it's just me, I can get it from the journal directly.

 

[Winfield Hill]

Jim Thompson wrote...

Doesn't that frost you? Adobe is getting as bad as M$oft for
generating version incompatibilities :-(

I read it on my computer with Adobe 6.0, so that's not the problem.

 

[The Phantom]

Fred Bloggs wrote...

Testing the posting just now - it downloads and displays fine.
But it's a two-part post, because of the binary file's length.
Perhaps your viewing program didn't successfully download the
second part to complete the file? Would you like me to repost
it to see if that fixes the problem?

I'm think you'd be interested in the article.

I've posted some NBS work that might provide an alternative.

 

[Winfield Hill]

The Phantom wrote...

I've posted some NBS work that might provide an alternative.

But only the front page?

 

[The Phantom]

The Phantom wrote...

But only the front page?

I see 5 TIF files attached to the posting. The front page is only the first. Check
again and let me know if you see the rest or not.

 

[Rich Grise]

John Larkin wrote...

The FEA says 0.7 inches. Whoa! Too big by far. It must
be time for plan B. Well, heck, what was plan B anyway?

Get a couple of pieces of aluminum foil, and some mylar shim
stock? ;-)

Cheers!
Rich

 

[Chris Jones]

Agilent HSFF or other 3D Field Solver would make short work of the
calculation. Assuming you don't have a 3D Field $olver (or you
wouldn't have asked the question) and you don't want to increase the
hole size until you reach 0.1pf, you could try the freeware FastCap
software from:

http://www.fastfieldsolvers.com/

supplemental user manual (main manual included in program download):
http://rleweb.mit.edu/vlsi/codes/FastCapsuppl.pdf

A search will turn up considerable info on FastCap; I haven't used it
but have heard it is a pain to use compared to commercial field
solvers and that it provides quite accurate results if you can figure
it out.

I've used FastCap quite a lot and I find it generally very good. (I also
like also FastHenry). The main problem with FastCap is that the input file
would be very tedious to generate by hand because you need to list the
x,y,z coordinates of the corners of a lot of triangles or rectangles, so
you would want to write a script to automate that. Another problem is that
the FastCap program relies on you to generate facets that are small enough
that the field can be regarded as constant over the facet. If you make the
facets too big, it will not converge (to a given error tolerance) and if
you make the facets too small you'll run out of memory or computing time.
If the program could decide on the facet size for itself that would be very
handy. At least it's open source so someone could do this if they are keen
enough.
Chris