Cadence® system design and verification solutions, integrated under our System Development 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.
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 technlogy. 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
Imagine you are days away
from completing the implementation of a fairly complex mixed-signal design, and
you are already day-dreaming about the vacation you have planned in a few weeks.
Then it happens -- the dreaded change in the design requiring ECOs to digital
or analog content, or worse yet, implementation problems that need fixing.
Should you call the travel agent to see if you can still buy travel insurance?
The fact is, for design
engineers, ECOs are a fact of life. Many digital design environments have implemented
fast and efficient ECO flows, which can accommodate pre and post mask ECOs. In the older generation of mixed signal
designs, the analog portion of the design was partitioned off, creating
physical boundaries between the digital and analog content. This made it easier
to incorporate changes in the digital or analog content without worrying too
much about creating problems in the interfaces between the two.
Challenges of ECO Management
Today's mixed signal
designs are implemented using a hierarchical methodology, and it is not
uncommon to find analog blocks residing inside digital functions that control
analog signals. What used to be a purely digital block is now incorporating
such things as power management features, which introduce analog content in
Two of the questions most
often asked in the context of mixed signal designs are:
The implementation of a
mixed-signal design may incorporate both netlist and schematic driven
methodologies. This is where parts of the design are represented by a netlist
while others are represented as schematics. For large mixed signal SoCs, it is very
important that the results from analysis of the top level floorplan be used to
drive implementation of the many blocks in the design, regardless of whether a
particular block is represented by a schematic or a netlist.
In addition, a methodology
is needed to allow for better communication between the top level designer and
those in charge of implementing the many blocks in the design. Without this
methodology, there is always a chance that the design of blocks end up
invalidating the analysis done at the top level.
How OpenAccess Supports ECOs
The Cadence mixed-signal
solution offers a concurrent mixed-signal floorplanning solution, which allows
for efficient, frequent and clear exchange of data between the top level designer
and those designing the lower level blocks. The solution is implemented on the
OpenAccess (OA) database, and allows for the exchange of floorplanning, placement
and routing constraints. In addition, the environment offers the capability to
imbed mixed-signal IP blocks with constraints that are used when instantiating such
IPs within a design, regardless of the environment used for implementing the
top level of the design.
To address the challenges
of performing ECOs on mixed signal designs, Cadence has implemented powerful
ECO functionalities that perform ECOs on the actual OA database,
containing both custom and P&R objects. For example a design containing
P-cells can be ECO'ed in the Encounter environment without the need to separate
out the custom objects in the design. The following figure depicts the pre-mask
ECO flow that implements changes made to the netlist.
The first step in this
flow is to open the pre-ECO database in the Encounter Digital Implementation
System (EDI) using the restoreOaDesign
command. As you can see, there is no need for a LEF technology library,
as a common OA PDK can be used for the EDI and Virtuoso environments,
containing all technology information needed for the mixed-signal
A Verilog netlist is then
extracted from the OA database, which can contain P-cells, if they existed in
the design. The Verilog netlist can now be edited to make the necessary
changes. In EDI, the command ecoOaDesign can now be used to read in the changes
in the Verilog netlist, while maintaining the floorplanning, placement,
routing, and other aspects of the pre-ECO OA database.
If new instances have been
added to the design, and the design takes advantage of low power features, additional
steps are required to repair the power domain, using CPF. At this point the
design is ready to go through ECO placement, or the user can optionally use other
features of EDI to guide placement of the new unplaced cells in the design.
Once ECO routing is completed, and any DRC issues resolved, the user can save
the full OpenAccess database, with ECOs.
Similar flows exist for
post-mask ECOs, as well as ECOs to the OA database, using the Virtuoso
Very good material Ben.