( SNUG 99 Item 38 ) ----------------------------------------------- [3/31/99]

   "This user paper was given by an employee of Motorola (Austin) and
    described this user's experience using the Synopsys EPIC PowerMill,
    with the ACE option, to simulate a PLL.   This user paper won 2nd place
    overall and was an excellent presentation of this user's "real world"
    experiences using a new tool on a project with an extremely tight
    schedule (he said he had 8 months to tapeout his PLL design).  The
    author presented what features of the tool he found useful, how the
    tool compared in accuracy to MSSPICE (Motorola's version of Spice) - he
    said the tools were within 5% of each other, and many lessons learned
    using the tool.  Knowing nothing about this tool, but knowing the
    gotcha's of using any new tool, I found his presentation extremely
    insightful as he clearly described to the audience the dangers of using
    certain modes and switches of the ACE tool, and the consequences of
    using these modes/switches.  He described that the ACE tool was faster
    than Spice by several orders of magnitude, but to achieve this
    performance, the tool "ignores" certain capacitors and resistors whose
    values are below some preset number.  He told the users how to modify
    these preset values so that they can properly simulate circuits which
    may have elements that would otherwise be automatically deleted by the
    tool.  This was just one example of many useful tips the author
    presented.  The bottom line is that the author said that after he
    learned how to use this tool, it allowed him to "almost" meet his
    original schedule, a schedule he said he would have had NO chance of
    meeting if he had to use Spice.

    Although I don't plan on using ACE anytime in the near future, I
    appreciated the usefulness of this paper to anyone who may be planning
    on using the tool."

       - Ken Banas of Basis Communications Corp.