The Value of Virtuoso as an Ecosystem

An ecosystem as defined by Webster's is a "system formed by the interaction of a community of organisms with their environment". This describes perfectly the methodologies so common for analog and custom IC design.  Unable to strictly rely on automation or synthesis, the custom design flow is chock full of interactive niche methodologies that have become the differentiator of most analog IC suppliers.  But, these methodologies are only at their most effective when their interaction is made as tight as possible.  The tightness is required to provide the end user the most cohesive design analysis possible.  Moving "in and out" of the design flow leads to big mistakes if not carefully monitored.  But where are the important touch points in a design flow?  What provides the end user with the right amount of cohesion without a cohersion to use non-integrated tools adding risk to the schedule?  Let me argue that Cadence's Virtuoso custom design platform finds the right middle ground with its built-in extensibility.  The early developers of the Virtuoso custom design platform understood the need for customization and built a solution that was extensible through either C++ or Cadence's own SKILL programming language.

Our customers have come to rely on the extensibility of Virtuoso in several ways. Larger customers use it to link in their own proprietary tools into the over all Virtuoso design flow to help them differentiate themselves.  These proprietary tools are often customized to exploit the company's particular design flow needs, and are usually considered ways for them to gain a productivity advantage in the overall design methodology.  The introduction of the OpenAccess database further assisted this effort by removing "translation" barriers common to the old methodologies, such as LEF/DEF.  If the integrated tools could take advantage of a common database, tighter coupling is possible.  Cadence takes advantage of this coupling by combining Virtuoso with Cadence's other paltforms (Incisive, Encounter and Allegro) to provide larger macro-solutions.

Another way customers depend on the extensibility is via links between Cadence tools and other commercially available EDA tools. This is where the Cadence Connections program comes in to help.  While it is true that some of these members provide competitive products to Cadence's, they are mostly working on products that fill niches in the custom design flow where for business reasons, it doesn't make sense for Cadence to be in the market.  Those reasons can include everything from it being too small (and therefore best served by a small focused company) to the entrance barrier to get into that market is too high it to be profitable for us.

Beyond integrations, Cadence does a lot of work with other vendors that supply the larger ecosystem.  The best example is our work with the world's foundries to build Process Design Kits. PDKs are the "rocket fuel" that accelerates the Virtuoso custom design flow.  However, this has become a controversial link point.  There are those industry pundits who argue that a single interoperable pCell provides tighter linkage that going through the Virtuoso framework to SKILL pCells.  But at what cost?  Remember, analog and custom designers want accuracy combined with ease of use in the design flow.  If pCells are designed to the lowest common denominator, so that in theory it is interoperable with every design tool, what is the value of the pCell?  Due to the physical properties of a pCell, I would argue for tighter integration into the design flow you are using.  As it is, quite a few customers feel the need to rewrite existing PDK's to make them more accurate to the design styles they are using.  By providing the end-user with a pCell that is even further abstracted from the truth, the end user is left with even a greater amount of work to do. We don't think that is a plan for success and have thus shuned efforts to drive the industry in this direction.

Cadence has provided the Virtuoso ecosystem to our customers and our competitors for nearly 2 decades.  As we move through these tough economic times, you can at least be  assured that the value of Virtuoso as the hub of the custom ecosystem will be maintained.