Happy 40th, HSPICE! Looking Forward to the Next 40 Years of Circuit Simulation Innovation

Anand Thiruvengadam, Tao Huang

Dec 13, 2021 / 4 min read

Reinvention is often a necessary path toward success. Netflix, for example, got its start mailing DVDs to its customers, but with the advent of video streaming, the company soon pivoted to streaming movies online and the rest, as they say, is history. Amazon’s rise is also well charted, from its origins as an online bookseller to an e-commerce and cloud computing leader today. And did you know that Play-Doh, before becoming a purveyor of its colorful clay, started off selling this product as a cleaner for removing coal residue from wallpaper in the 1930s?

“Innovate or die” is a catch phrase that’s been bandied about in tech circles, and there’s really no denying its veracity. Organizations that can stay ahead of the pace of change are the ones that thrive. The same can be said for technologies, and this point is well illustrated by HSPICE® circuit simulation technology.

HSPICE technology didn’t become the industry gold standard by standing still. As simulation challenges evolved over the years, so has HSPICE. In this blog post, we’ll discuss how HSPICE, which celebrates its 40th birthday this year, has continued to reinvent itself to help you design high-performing chips. Read on for some interesting insights about its major waves of change that have allowed it to remain impactful and relevant as the chip landscape has evolved.

An artificially intelligent computer concept with futuristic design

The First Three Waves of HSPICE Reinvention

Circuit simulation plays a critical role in ensuring that silicon chips will perform as intended. After all, we can’t afford to have critical applications like vehicle braking systems, robotic surgical equipment, or 24/7 manufacturing lines failing because of chip issues. As silicon designs have grown larger and more complex, new simulation challenges have emerged. In answer to this, HSPICE technology has evolved to meet the needs.

HSPICE got its start in the 1980s as an analog circuit simulator based on the SPICE (Simulation Program with Integrated Circuits Emphasis) technology that came out of UC Berkeley. It’s one of the more prominent commercial versions of SPICE (originally commercialized by Meta-Software, now part of Synopsys). By simulating their circuits prior to manufacturing, engineers could verify operation at the transistor level. It’s not practical to prototype ICs prior to the manufacturing step. With SPICE simulation, designers could accurately predict design behavior and estimate how component variations could impact performance and more. During these days, ICs were relatively small, each containing a small number of analog components.

Then came the digital revolution.

With the emergence of digital components came the first wave of HSPICE reinvention, when it evolved to become the gold standard for characterization of standard cell libraries. With analog ICs, HSPICE technology was used to simulate the entire circuit. Digital designers, on the other hand, use standard cells in design steps such as synthesis and place and route. Foundries use HSPICE to simulate and characterize these standard cells before building the cell libraries used to implement the digital designs.

From analog circuit simulator to a solution for today’s hyper-convergent designs

The second wave of HSPICE reinvention came with the emergence of faster, more complex high-speed IOs and memory interfaces. Say you have a motherboard with a microprocessor and DRAM. The interface between the two needs to be a very fast signal implemented directly on the motherboard, so then it becomes important to analyze signal and power integrity of the PCB. HSPICE rose to the challenge by incorporating advanced signal and power integrity modeling features, thus becoming the.  de facto standard for uncovering signal integrity and power integrity problems. Its ability to effectively evaluate and identify errors in the transmission of billions of bits makes it an ideal solution for accelerating the creation and analysis of designs with fast and complex high-speed interfaces.

Today, we’re in an era of hyper-convergent chip designs, where scale and systemic complexity are marked by multiple technologies, protocols, and architectures coming together in a massive, highly complex, and interdependent design. This evolution has pushed circuit simulation into a domain where accurate modeling, robust algorithms, and strong compatibility are keys to success. In addition, large, heterogeneous system-in-package designs urgently demand complex, multi-dimensional analysis and improved quality-of-results, time-to-results, and cost-of-results.

Ensuring that these hyper-convergent chips will work as intended takes on an entirely new level of challenges. In addition to scale and systemic complexity, there’s also scope complexity, with on-chip and off-chip components to consider. For example, 3DICs have emerged during this period, with even more complex signal integrity and power integrity demands as signals move between different dies that are connected with through-silicon vias (TSVs) and bond wires. In this third wave of reinvention, HSPICE technology has become a bridge to connect the on- and off-chip worlds—a feat that other simulation technologies cannot match.

Gold Standard for Circuit Simulation

The latest HSPICE reinvention has come in the form of intelligent, machine-driven SPICE simulation based on advanced machine-learning (ML) algorithms and a new name and packaging. HSPICE, now rebranded as PrimeSim HSPICE, is part of Synopsys PrimeSim™ Continuum, a unified workflow of next-generation circuit simulation technologies. PrimeSim HSPICE remains the gold standard for accurate circuit simulation with differentiated capabilities for analog simulation, standard cell and memory characterization, and signal integrity analysis. New ML algorithms in the PrimeSim HSPICE solution help designers rapidly analyze the impact of variability and identify design weaknesses on complex advanced-node designs in a cost-efficient manner.

What’s Next for HSPICE?

HSPICE has successfully reinvented itself time and again, so what’s next for HSPICE technology? Looking ahead, here are three key areas to watch for:

  • Core performance improvements with increased robustness for accurate SPICE simulation, to help designers achieve results faster
  • Technologies to assist designers in improving overall design coverage
  • ML-driven analysis flows to help designers analyze weaknesses, optimize design parameters, and effectively debug when something is wrong

In addition, HSPICE technology is also coming full circle. When the technology was born 40 years ago, computations were typically performed in a faraway server as designers worked on desktop terminals. Then came the era of workstations and local machines. Today, many EDA tasks, including circuit simulation, are performed on the cloud. PrimeSim HSPICE is now enabled and optimized to run on leading cloud platforms.

Designers aim to build the best chips and to do so faster than ever, so they need better, faster circuit simulation tools. While the best chips today are much more complex than their predecessors, HSPICE technology has risen to the occasion again and again, providing a speedy, accurate gold-standard simulation solution that designers can trust.

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