With the recent release of unified custom/analog flow that is based on the latest version of the Virtuoso IC 6.1.5 technologies (see Virtuoso IC 6.1.5 press release here), it is time to revisit the strengths of Virtuoso IC 6.1 platform and find out how new capabilities enable designers with the productivity gains they have been clamoring for.
Open Access and SKILL
One of the major changes in Virtuoso IC 6.1 is the database. For the last 20 years, the Cadence Data Base (CDB) has been used. However, starting from IC 6.1, keeping pace with the "open source" movement and the Cadence goal of an open environment, we have started using the Open Access (OA) database. This allows custom/analog teams to save the data in a format that can be accessed by applications from different EDA vendors without the need for translation.
The OA database was built by Cadence and was donated to Silicon Integration Initiative (Si2) to encourage the adoption of it by other EDA vendors. The OA database was architected and developed to handle larger designs, offer faster response and enable easier implementation. Cadence works closely with customers who are migrating to Virtuoso IC 6.1 technology by providing technical help and application resources to make the migration as seamless as possible.
Cadence users know that the SKILL language plays a central role in our technologies. All the PDK and GUI development is done in SKILL and many tools that integrate into Virtuoso technologies do so using SKILL. SKILL is ubiquitous in PDK development with each and every major foundry supplying SKILL PCells as part of their PDKs.
In Virtuoso IC 6.1, we greatly improved the functionality of SKILL. Cadence recognizes that a new crop of CAD engineers and software developers are more in-tune with object oriented programming concepts. To let engineers take advantage of these techniques in customizing their design flows, Cadence has made SKILL++ available to developers. Like other object oriented programming languages, SKILL++ lets CAD teams take advantage of latest developments in software programming in customizing their design flows and methodologies.
Virtuoso Schematic Editor
The Industry leading Cadence Virtuoso Schematic Editor provides custom/analog engineers with an easy to use design entry tool with various capabilities to enable fast, intuitive, and comprehensive schematic capture. To ensure a smooth and easy transition to Virtuoso IC 6.1, the same look and feel and a similar use model was maintained, at the same time providing engineers with features and capabilities to increase the productivity in their day-to-day design activities. Features include:
Virtuoso IC 6.1 is the first release to enable constraint-driven design. Constraints are design rules that allow design teams to maintain design intent throughout the design cycle. Instead of relying on schematic notes, emails and various other documents, constraints provide a systemic methodology to maintain consistent information between front-end designers and back-end physical implementation teams. Easy-to use constraint entry mechanism and constraint notes in Virtuoso IC 6.1 allows for formal communication mechanism across the team members.
To know more about Virtuoso Schematic Editor, click here
In the next few blogs, I will showcase the Virtuoso Analog Design Environment and give you detailed look at its capabilities so that users can find out how the new and improved Virtuoso Analog Design Environment enables designer productivity.
Related Blog Posts
Rapid Analog Prototyping - Handcrafted Layout Gets a Needed Productivity Boost
Early Analysis is Key - Parasitic-Aware Design
Virtuoso IC6.1.5: Software and Fine Red Wine
How Parasitic-Aware Design Flow Improves Custom/Analog Productivity
Virtuoso IC 6.1 is a maybe a fine tool for digital schematic designers, and for sure, it is a big improvement regarding the interface capabilities and visuals. Now for analog layout designers, it is a different song as it seems that the tool was created mainly for digital designs. It still lacks some maturity and adapted flexibility to handle a custom analog design as good as the old and venerable cdb-based Virtuoso.
As a matter of fact, we have been using this version on all new projects since the beginning of the year, so we had some time to build metrics: on the layout implementation productivity, the old Virtuoso cdb based environment still outperforms the new Virtuoso by a fair 20%.
Thank you for your comments.
I work in Virtuoso Layout product management and would like to better understand the challenges you are experiencing with IC6.1 layout. I have also specifically worked with several customers on developing metrics and measuring productivity on IC6.1, so I would be interested to hear more about your method as well. Some of those working arrangements with customers started out in a similar situation as yours, after their first experience with IC6.1 and we were able to collectively and quickly make improvements. Please contact me directly at firstname.lastname@example.org, and I would be glad to follow up with you.
Thank you again.