In a meeting last week with a potential customer, I jotted down the following notes on their experience using another company’s CDC (clock domain crossing) tool:

The designs were 300k – 2M gates with 10 clock domains
They had lots of issues reading the design in, and had to write a bunch of wrappers to get the VHDL through
It took 10-15 days to setup each module for CDC analysis
FIFOs were not recognized by the tool
Many useless messages were hiding real design problems
They found 4 bugs in the CDC tool itself
After a long struggle, they could not verify CDC successfully on any of their designs
That’s why they are talking to Real Intent

In fact, I hear this kind of story at every company I visit. If this sounds like the painful experience you have with your current CDC tool, read on, because you should know that CDC analysis can be much simpler, with the right solution! That’s what customers who have switched to Real Intent are telling us! Check out the latest newsletter to see our user survey results!

Here are the top 3 reasons why companies are switching to Meridian CDC:

1) Ease of setup – Setup is a very time consuming step in our main competitor’s flow, taking almost 80% of the time as stated by customers. Unfortunately, when you have garbage going in, you get garbage out. So you have to spend a lot of time to setup the other tool to get somewhat meaningful info out. One of my engineer friends recently told me that you almost have to know the answer before setting up the tool in order to get the results – WOW!!! Productivity goes out the door.

Meridian CDC, based on Real Intent’s years of experience in understanding designers’ intent, can automatically extract the clock/reset/constant/static intent from the design or the SDC file to ensure proper setup. 90% of setup is done for you automatically! You’ll be getting real results from Meridian CDC while other engineers are still figuring out how to set up the competing CDC tool.

2) Noise – This is primarily a consequence of poor setup. Since setup takes much painful work and lots of time with the other tool, often designers under time constraints have no choice but to forge ahead to the CDC analysis stage without complete setup so some progress and results can be shown to management. However, finding bugs in the mountain of erroneous messages is a formidable task. Many veteran CDC tool users have gone through tens of thousands of messages before giving up on the analysis altogether. This is a repetitive theme I hear in my meetings!

Why is Meridian CDC better? Because of the three underlying principles built in the tool: 1) Meridian CDC invests a lot of effort up front to automatically create the proper setup for users, so their manual effort is minimized. Users are much more willing to invest the remaining 10% effort to ensure complete setup; 2) Meridian CDC provides comprehensive feedback on user setup so refinement can be done easily; 3) Meridian CDC analysis is smarter in reporting root causes of problems, not the many symptoms of problems. As a result, quality and accuracy of results are easily achieved!

3) Performance – Have you waited days in order to get CDC results? Wait no more! Meridian CDC is on average 10X faster than competition! Finish your project early and take a vacation!

4) Coverage – Oops, this is the fourth one! Well, at least you might expect good coverage from our competition when they report tens of thousands of messages! NOT SO. Aside from false-positives, they also have a great deal of false-negatives, or missed issues. There is nothing worse than a chip re-spin if you don’t catch a problem in simulation.

Meridian CDC offers a layered approach to CDC signoff to make sure every stone is turned in order to find sneaky CDC bugs and guarantee CDC-safe designs. Following Meridian CDC’s recommended methodology, you can rest assured that no CDC bugs will make it to silicon!

The bottom line – Doing CDC verification takes a Real CDC tool architected to do the job, not a linter adapted to do CDC work. Perhaps it was ok 8-10 years ago when a meager linter could do the job of finding possible clock crossings in a small design with a 10-20 clock domains. However, today’s multi-million gate designs may have 100+ clocks and several layers of hierarchy. Using a linter on these is like playing tennis with a ping-pong paddle.

If it is painful setting up your CDC tool, if your CDC analysis takes a long time to finish, and if you are tired of weeding through tens of thousands of messages to find bugs, it is time to look at Meridian CDC! Many customers have done so successfully as evidenced by Real Intent’s rapid growth in 2010 (watch out for the press release coming out this week). So why not YOU?

Jan 24, 2011