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Archive for September, 2014

Correct by Construction

Monday, September 22nd, 2014

Gabe Moretti, Senior Editor

In the late eighties and the nineties there was a lot of development work around Hardware Description Languages with the scope of creating IEEE standards.  The work did produce VHDL and Verilog standards that have been fundamental in the growth of EDA.  One of the topics of discussion at the time was the goal of creating a tool that would allow engineers to create “Correct by Construction” designs.  Now you can use IP Subsystems, but more on that later.

We never succeeded because of semantics ambiguities in languages that were too difficult to avoid.  Such a language would have been very complex and follow-on attempts have increased the knowledge of how HD languages can be developed, but no working language fulfilling the Correct by Construction goal has been developed.

Of course EDA has produced tools that generate “Correct by Construction” hardware.  RTL synthesis tools in fact do generate such hardware, although even there designers must be careful to use proper semantics or strange hardware will result.  Unambiguous semantics is the major obstacle to what was once called behavioral synthesis.  Avoiding ambiguity was such a problem that these tools have had to undergo a name change in order to even undergo feasibility testing by prospective users.

High Level Synthesis, this is the name of such tools now, have demonstrated acceptable capabilities now, but more work is being done to improve their capabilities.  But major obstacles still exist.  Without doubt the biggest obstacle is the fact that systems are not homogeneous.   Although there are still a significant number of fully digital IC’s produced, more often now designers must deal with mixed/ signals, Analog, and electro-mechanical systems.  And we really do not yet know how to synthesize these.

I think we never will have to, thanks to the advent of Subsystems IP.  Just like before synthesis engineers used to connect various components from data books to create a system, now designers use IP subsystems.  The IP market has grown no just in economics terms, but most importantly, in technical terms.  It is now possible to use a third party IP to implement graphics capabilities, to provide in-chip busses and networks, to provide various types of wireless communications, and so on.

Of course these are solutions that also generate engineering and business challenges.  What is, for example, an acceptable acceptance test procedure?  How can the license protect the assets of the IP provider?  What and how is delivered to the end user of the IP?  Do we have a standard procedure for the successful transmission of IP subsystems from suppliers to users?  As we know Correct by Construction is not achieved only through algorithms; we need methods as well.

These and other such issues will be discussed on Tuesday October 14 at the IPExtreme Constellations workshop ( .  I will be there moderating a panel on the topic.

3D-IC’s Are the Future

Friday, September 12th, 2014

Gabe Moretti, Senior Editor

Looking at a cross section of a 3D-IC one can most of the time see two or more distinct functional systems stacked over each other.  These devices have taken the clue from real estate in order to find their initial architecture.  When the lot (in this case the die) is too small, go vertical.  So 3D-IC’s look like a multi-story building.

Each die is a stand alone functional system that cooperates with the other die to form a complete solution.  We can say that most 3D-IC’s are really a packaging solution, not a system solution.  Right now, due also to limitations in most EDA tools connections are built in two dimensions.  The connection between the two or more dies happen as a result of integrating the communication among the systems.  What if every cell could have six possible ways to connect instead of four?

I found scholarly papers on 3D-IC as far back as 2005.  Not that there are none previously, I just did not find them.  And a few of those I read did mention the problem of “thinking in three dimensions”.  I think that soon engineers will learn to design in three dimensions and this will require significant development on the part of EDA tools vendors.  There is really no reason why IC designers should not have the same freedom as PCB designers who enjoy a number of layers onto which to distribute the various components forming the system.  And by the way, would there be an advantage to have power and ground on their separate IC layers?  Or may be have a power bus that is thermally and electronically insulated from most, if not all, components?

Much has been written in the last few months about the “death” of Moore’s Law.  If we can design in three dimensions, then the Law is not dead.  We just have to define the area as a volume, and not just as a plane.  Yes, I agree, it would take some sophisticated partitioning algorithm to divide a block into two, or more, planes instead of a plane.  And I wonder, is it really optimal to separate vertically digital from analog and RF components?  What if we could find that a vertical RF module distributed on more than one layer is better?  Has someone thought of considering it?

I agree that manufacturing a 3D-IC is more challenging and yield is often mentioned as an obstacle to the growth of 3D-IC popularity.  But, if a less challenging process could be used while at the same time take advantage of the latest versions of EDA tools, as Dr. Antun Domic of Synopsys suggested at DAC 2014, would the yield problem be significantly minimized if not all together eliminated?

Think outside the box by building the box and find a new way to grow.

Supporting Education to Build the Future of EDA

Friday, September 5th, 2014

Gabe Moretti, Senior Editor

A grown industry looks at the future, not just to short term income.  EDA is demonstrating to be such an industry with significant participation by its members to foster and support the education of its future developers and users through educational licenses and other projects that foster education.

A couple of months ago I received a press release from Dassault Systemes a French EDA vendor.  Dassault is one of the most important French companies and I remember visiting them to promote what is now Mentor Graphics Expedition PCB product when I was with VeriBest.  At the time Dassault Systemes was their internal CAD developer, but it has grown and started selling their own products.   The company has also focused in supporting education and now has more than 100,000 users of SOLIDWORKS Education Edition.  The latest version includes numerous new additions to its 3D design software applications portfolio, delivering a rich array of offerings that further the ability of students to design, including 3D CAD, Simulation, Product Data Management, Technical Communication and Electrical Design.

What as attracted my attention is that the tool is also used to develop robotic applications, including drones.  Academic users are part of an organization called SOLIDWORKS Associates, and many American universities belong to it.  One of the many new features of the present version is a collection of Teaching Guides and lessons to provide educators with additional support for developing Science, Technology, Engineering, and Mathematics (STEM) curriculum.  Qualified schools are given SOLIDWORKS Student Edition licenses at no charge for use by their students outside the classroom. In addition, schools with a SOLIDWORKS Education subscription can become Certified SOLIDWORKS Academic Exam Providers and administer the Certified SOLIDWORKS Associate (CSWA) exam to their students.

“The world needs engineers, innovators, and design leaders.  Dassault Systemes is committed to improving STEM education and bringing those next generation leaders to the forefront,” said Bertrand Sicot, CEO, SOLIDWORKS, Dassault Systemes. “The SOLIDWORKS education community is full of SAE Collegiate Design Series competitors and FIRST Robotics winners.”

Beginning with the introduction of the new version all FIRST Robotics teams have become eligible for a SOLIDWORKS Robotics Sponsorship, which is based on and includes SOLIDWORKS Education Edition 2014-2015.

What Dassault Systemes does to support education is just one example of the involvement of EDA vendors in providing students with tools that help them familiarize themselves with what the industry does.