( BSNUG 00 Item 8 ) ------------------------------------------- [ 10/13/00 ]
Subject: Library Compiler, Non-Linear Delay Models, IBM'S DCL, IEEE 1481
SURPRIZES: In one of the most unexpected quirks at this year's Boston SNUG
gathering, the Best Paper was not given to a typical mainstream presentation
on something like FSMs, Verilog coding styles, or DC tricks -- but to a
paper on Library Compiler, Synopsys NLDM libraries and how to fix them
(by Steve Start of American Microsystems, Inc.) Why? Those facing NLDM's
complicated issues really, really liked Steve's paper.
"In one of the user sessions, an IBM engineer presented a paper on DCL.
DCL was adopted as an IEEE standard (IEEE 1481) in June 1999 and is
aimed at providing a common set of library rules for all EDA tools.
DCL is an industry initiative aimed at moving away from the "Synopsys
.lib standard" to an industry standard that will improve accuracy,
consistency, and functionality for all EDA tools that use it. DCL
still hasn't gained wide acceptance but larger players such as IBM
and Synopsys are investing a lot of effort to incorporate and utilize
the IEEE standard. Not yet ready for prime time but steady progress
is still being made.
Dallas Semiconductor/Silicon Metrics presented a paper which reinforced
and reiterated much of what we covered in our paper about the potential
for inaccuracies in Synopsys NLDM libraries and how to fix them.
Dallas Semi. had purchased design libraries for synthesis and
simulation that turned out to be very poor in quality. They reported
delay calculation differences between Synopsys NLDMs and HSPICE that
were in excess of 40% in some cases. They used tools from Silicon
Metrics to recharacterize the Non-Linear Delay Models in their Synopsys
libraries, reducing the delay calculation error to 1 to 2%. Silicon
Metric's solution lists for about $150k."
- Steve Start of American Microsystems, Inc.
"Library Compiler:
We only had about 15 people in the room for the presentations, with the
majority involved in their own library development. Obviously, that's
not an area of interest to many Synopsys users.
Two presentations focused on the difficulties of modelling with
non-linear delay models in .lib. Steve Start gave a great overview of
the work he has done at American Microsystems on running tests to
refine non-linear delay models through repositioning grid points
to reduce maximum error & adding an offset to cancel out more error."
- Chris Kiegle of IBM
|
|
