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The great architect Frank Lloyd
Wright once said "you can fix it on the drafting board with an eraser, or on
the construction site with a sledge hammer." The semiconductor design industry
is a perfect example where finding issues later in the flow can be extremely
expensive. Chips that fail in high-volume consumer products can cost companies
hundreds of millions or even a billion dollars, and there is huge benefit to
validating the design and identifying and fixing issues early in the design
To address this issue, First
Encounter introduced the concept of design exploration and planning in IC
design nearly 10 years ago. This enabled designers to build early prototypes of
their chips and resolve issues that usually came late in the design cycle,
along the critical path toward reaching final tapeout. This significantly
reduced the overall turn-around time of the design flow and provided huge gains
in productivity and predictability of the design process and schedule. Design
exploration and planning has since become an integral part of any IC design
flow and has changed significantly over the years to keep up with the growing
chip size and complexity in accordance with Moore's Law.
Robust Hierarchical Methodology
While hierarchical methodologies
were fairly immature back in the days as most designs were done flat or
bottom-up, today any productive design exploration and planning solution
requires a robust hierarchical methodology to support the big designs of today.
Cadence has been a leader in this area, and both First Encounter and the Encounter
Digital Implementation System support various hierarchical design styles such
as channel-based, channel-less, micro-channels or master-clone.
The hierarchical support in
Encounter helps physical designers assess how best to partition the logical
hierarchy into physical modules by analyzing the optimal pin assignments;
creating accurate time budgets; accurately predicting the clock distribution
networks; analyzing the power grids; and eventually generating complete timing
and physical constraints for each of the physical modules. To further handle
the Giga-Gate designs of today, we have developed a new data abstraction
technology. This unique capability allows netlist compression up to 90% while
maintaining relevant timing and congestion information, resulting in faster
turnaround time and one pass implementation handoff.
Implementation Quality Automation
In addition, the growing chip
functionality in a shrinking time to market window demands increasing
automation to get early feedback, while still providing results good enough for
implementation. A case in point is the automation in macro placement. To
address the ever-increasing number of hard macros on a design, Automated
Floorplan Synthesis in First Encounter now enables concurrent standard cell and
macro placement that helps designers to generate implementation quality
floorplans for both flat and hierarchical designs.
The Floorplan Ranking capability
further empowers designers to general multiple floorplans in parallel and rank
them based on different criteria such as timing and area. This enables
designers to do a quick feasibility analysis and make informed trade-offs early
in the floorplanning stage.
Furthermore, there is growing
concern for advanced-node support and low-power today as wireless chips
dominate the consumer market. To address this, First Encounter also supports
the Common Power Format (CPF), advanced low-power techniques, and design-for-yield capabilities that are critical for power hungry and
advanced node designs.
First Encounter today is an integral
part of the Cadence Digital End-to-End Solution. It paves the way for Silicon
Realization by providing a comprehensive design planning and debug environment
that captures the design intent upfront, enables large scale designs with its
unique abstraction capabilities and provides a predictable convergent path for
hierarchical design closure. With the ever-growing chip complexity, design
planning and prototyping will continue to gain significance in the IC design
flow. The pay-offs will be in the form of overall increased productivity,
predictability and profitability. I am sure we will continue to see growing
innovation in this area and it will be fascinating to see how this space
reshapes in the future.