( ESNUG 365 Item 2 ) --------------------------------------------- [02/15/01]

From: Jay McDougal <jay_mcdougal@agilent.com>
Subject: Run-Time Issues w/ Cadence PKS; Area Issues w/ Synopsys PhysOpt

John,

Our dual PhysOpt/PKS tape-out was done because we ran into some run-time
issues with PKS on that core.  It was taking 6 days to compile and we
couldn't get any debug/improvement cycles in.  The PhysOpt run took about
1 day but had about 10% larger area.  So, I used Ambit to get an initial
netlist with the area savings and PhysOpt to get a placement.  I then
returned to PKS after our internal scan insertion tool and clock tree
generation to do the final timing tweaks.  This allowed me to use the SE
compatible global router in PKS, do incremental optimization based on that
global route, and get less than 2% difference in pre- and post- final route
timing in SE.  With a PhysOpt placement, we see 5-10% difference in pre-
and post- route timing.

    - Jay McDougal
      Agilent                                    Corvallis, OR