Package Parasitics continued (fwd)

I've just joined this dialog & find it interesting to see you debating
something we are discussing in-house. Furthermore, I made a suggestion
for a package modeling specification at the February JEDEC JC-15 meeting.
I'm trying to get consensus in-house still, but what I have put into my
proposed spec is both the RLGC info & a spice deck. The RLGC info is
useful for thinking purposes. The spice deck is what we need for
simulation. No one wants to build a spice deck from an RLGC matrix.
A "cut & paste" approach is needed for productivity. Furthermore, the
lumped element spice deck should be made up of 3 lumps. 1 lump introduces
distortion.

I did not expect IBIS to satisfy all my needs. But my proposed package
modeling spec is my wish list for signal integrity. The goal is improved
productivity. I was hoping to get the IC manufacturers moving towards
giving us more of the information we need to do signal integrity analysis
with greater accuracy & less labor. If there is interest, I could share
the spec with you when it comes "out of committee". (Perhaps "data
requirements" is a better term than "spec".)

----------------------------------------------------------------------
Forwarded message:
> From cer@Cadence.COM Fri Oct 1 14:12:38 1993
> Date: Fri, 1 Oct 93 13:31:55 -0400
> From: cer@Cadence.COM (Christopher E. Reid)
> Message-Id: <9310011731.AA20082@oahu>
> To: ibis@vhdl.org
> Subject: Package Parasitics continued
> Cc: cpk@Cadence.COM
>
> Hello All,
>
> Responding to Eric Bracken again, he writes:
> ______________________________________________________________________
> I propose the same thing; but I suggest we represent the matrices as a
> SPICE deck. This is a well-known, industry standard format that
> everyone understands. The symmetry is implicit in the SPICE. The
> "banded" (or more generally, "sparse") nature of the matrix will be
> there if you don't specify the coupling between far-off elements.
> Finally, the SPICE provides flexibility to describe discontinuities
> between bond wires, lead frame and pins.
> --------------------------------------------------------------------
>
> However, my point is that:
> 1) RLGC Matricies are much easier to manipulate, for example to
> compare coupling strengths.
> 2) RLGC Matricies are easily translated into equivalent SPICE decks.
> 3) It is difficult to make the translation from SPICE to
> RLGC matricies since that would entail parsing the SPICE deck,
> and checking to make sure no other elements were present.
>
> Of course SPICE is more generic, but I think that generality is not
> required here.
>
> Chris Reid
> cer@cadence.com

-- 
Bob Canright		Convex Computer Corp.	Richardson, Texas
214-497-4474 (desk)	canright@convex.com	214-497-4500 (FAX)
disclaimer:
It's not my typing, the Sun keyboard repeeeatsss.