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.
Get email delivery of the Cadence blog featured here
OK, so the title is perhaps a little optimistic but I'm
playing off the saying "keep your friends close, but your enemies closer" (The
Godfather Part II: Francis Ford Coppola and Mario Puza). The corollary in
custom design is to bring the understanding of parasitic effects as early as
possible in the design flow, so there is less chance of surprises later.
In custom design there are a few ways to bring your
parasitic effects "closer." They are as follows:
1. The first is
perhaps the most painful. It's where parasitic Rs and Cs are manually added
directly on the schematic in the hope they are representative enough to cover
the layout. So a duplicate of the design is created to protect the original.
companies have created scripts that will add a default parasitic capacitance to
every net in the design to at least push the design closer to the final result.
This can be done during the netlisting phase to avoid editing the schematic.
3. Other companies
have gone a step further and added in a level of structure recognition, so the
guesstimated parasitic elements are closer to what a layout would likely
produce. The estimates are programmed in, based on prior experience.
designs are typically 80% reused, it makes sense to try and leverage the 80% of
parasitic information you have from the previous designs. There are a number of
ways designers will do this, and depends on how much information is wanted.
Again some scripts are often developed to help.
5. Lastly is the
prototype route, where the design is actually constructed very quickly to get
access to extracted results. This depends on a high level of automation in the
layout generation to make it worthwhile.
Below is a flow that I want to present that covers the last three points and is based on the Parasitic Aware Design (PAD) capabilities of Virtuoso
ADE GXL. The six steps are:
1. Create the
their effects and make adjustments to the design
the layout and extraction as before
4. Run the
5. Analyze the
pre/post layout impact on performance and recalibrate the estimates from the real extracted results
6. Reuse the
parasitic estimates in subsequent designs as the parasitic estimates are saved
as constraints and travel with the design.
The key challenge to any pre-layout parasitic analysis is
getting the estimates in the first place -- and the best estimates are going to
be those derived from real data. As I mentioned, some customers have developed
the ability to add parasitics based on some heuristics they developed over time
and scaled by the rules of the target process. With PAD, these can be included
into the flow using the SKILL interface. The advantage is you gain access to
all the other capabilities of PAD in ADE XL and GXL for analysis with these
The alternative is to create a prototype of the layout and
collect the extracted results directly. With the constraint-driven flow from
Virtuoso Schematic Editor XL to Virtuoso Layout Suite XL/GXL, a prototype can
be created quickly. Use QRC to extract and you can run verification, then
either stitch parasitic networks of interest directly to your pre-layout design
or recalibrate any estimated parasitic.
With PAD, you have the most
flexibility in incorporating the strategy that makes the most sense to you.
With reuse built in, it is now more possible than ever to reduce or even
eliminate the iterations back and forth between design and implementation.
What strategy do you use?