Cadence® system design and verification solutions, integrated under our Verification Suite, provide the simulation, acceleration, emulation, and management capabilities.
Verification Suite Related Products A-Z
Cadence® digital design and signoff solutions provide a fast path to design closure and better predictability, helping you meet your power, performance, and area (PPA) targets.
Full-Flow Digital Solution Related Products A-Z
Cadence® custom, analog, and RF design solutions can help you save time by automating many routine tasks, from block-level and mixed-signal simulation to routing and library characterization.
Overview Related Products A-Z
Driving efficiency and accuracy in advanced packaging, system planning, and multi-fabric interoperability, Cadence® package implementation products deliver the automation and accuracy.
Cadence® PCB design solutions enable shorter, more predictable design cycles with greater integration of component design and system-level simulation for a constraint-driven flow.
An open IP platform for you to customize your app-driven SoC design.
Comprehensive solutions and methodologies.
Helping you meet your broader business goals.
A global customer support infrastructure with around-the-clock help.
More Support Log In
24/7 Support - Cadence Online Support
Locate the latest software updates, service request, technical documentation, solutions and more in your personalized environment.
Cadence offers various software services for download. This page describes our offerings, including the Allegro FREE Physical Viewer.
The Cadence Academic Network helps build strong relationships between academia and industry, and promotes the proliferation of leading-edge technologies and methodologies at universities renowned for their engineering and design excellence.
Participate in CDNLive
A huge knowledge exchange platform for academia to network with industry. We are looking for academic speakers to talk about their research to the industry attendees at the Academic Track at CDNLive EMEA and Silicon Valley.
Come & Meet Us @ Events
A huge knowledge exchange platform for academia. We are looking for academic speakers to talk about their research to industry attendees.
Americas University Software Program
Join the 250+ qualified Americas member universities who have already incorporated Cadence EDA software into their classrooms and academic research projects.
EMEA University Software Program
In EMEA, Cadence works with EUROPRACTICE to ensure cost-effective availability of our extensive electronic design automation (EDA) tools for non-commercial activities.
Apply Now For Jobs
If you are a recent college graduate or a student looking for internship. Visit our exclusive job search page for interns and recent college graduate jobs.
Cadence is a Great Place to do great work
Learn more about our internship program and visit our careers page to do meaningful work and make a great impact.
Get the most out of your investment in Cadence technologies through a wide range of training offerings.
Overview All Courses Asia Pacific EMEANorth America
Instructor-led training [ILT] are live classes that are offered in our state-of-the-art classrooms at our worldwide training centers, at your site, or as a Virtual classroom.
Online Training is delivered over the web to let you proceed at your own pace, anytime and anywhere.
Exchange ideas, news, technical information, and best practices.
The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information.
It's not all about the technology. Here we exchange ideas on the Cadence Academic Network and other subjects of general interest.
Cadence is a leading provider of system design tools, software, IP, and services.
Hi, I have now seen this issue with two different designs and have not been able to figure out the root cause for this behaviour.
I have synthesized a design using RTL Compiler and have generated both mapped and an optimized netlist.
1. When I compare the RTL to mapped netlist (non-hierarchical comparison), I don't see any non-equivalent points.
2. When I compare the mapped netlist to the final optimized netlist, I don't see any non-equivalent points.
3. But when I compare RTL to final optimized netlist, I get non-equivalent points.
Looking into this matter in detail, I noticed that these non-equivalent points start showing up as soon as I run the first incremental synthesis on the mapped netlist.
Any ideas as to why the RTL to final netlist comparison are showing non-equivalencies?
I have seen this happen before too, and in my case it was caused by sequential merging in RTL-Compiler. The two step LEC flow helps LEC resolve and verify sequential merging. The single step verification flow can often resolve sequential merging, but sometimes it cannot.
The two step LEC flow is the recommended way to verify RC netlists. I suggest you continue to use the two step flow. It is the best way to prevent false-noneqs and aborts.
In reply to bmiller:
Thanks for your input on the matter.
As far as the RTL to mapped netlist comparison is concerned, should that be hierarchical or would a non-hierarchical comparison suffice?
In reply to hnfq:
Whenever RTL is the "golden" design in LEC, you should use a hierarchical compare. This will be the most efficient, and give the best chance of a successful compare with no aborts.
Also, this is the default when using write_do_lec. If RTL is the golden, write_do_lec will write out a hierarchical compare script, unless you explicitly say -flat. Similarly, if you are generating a dofile with write_do_lec and you specify a -golden netlist (such as in the intermediate-to-final comparison), write_do_lec will default to writing a flat compare script.
Is there a reason why you would prefer a flat compare with RTL as the golden?
No, there wasn't any particular reason for running flat comparison. I just wanted to make sure that whether I run hierarchical or flat comparison I would be able to rely on the final result.
Appreciate your input on this issue. Thanks.
You can certainly rely on the final result whether you run flat or hierarchical.
If you'd like to have the option to run both ways, I suggest writing out two LEC dofiles with the write_do_lec command; one with -flat, and one without.
But, the preferred method is to run hierarchical if RTL is golden.
Can you explain what does sequential merging and sequential constanting mean?
In reply to Manoj Kumar S:
Sure. Sequential merging is when the synthesis tool merges two or more flops into one because they have the exact same function. Sequential constant is when the synthesis tool optimizes away flops that are always tied to 1'b1 or 1'b0.
Thank, I had the same Mismatch and your posts helped me also I found more Cdence blog.
In reply to r u verified:
unfortunately you do not include enough information for anyone to help you. You should include the schematic showing the nonEQ. You indicate LEC is confuse. Can you shed light why you think LEC is confused and the nonEQ is not real? Better yet, if the circuit is simple as you indicate, I believe the schematic should help you understand the difference and whether it is a real issue, setup issue, or something else.
hope this helps,