Sign In
Forgot Password?
Sign In | | Create Account


Improved Simulation Performance and Time-to Market Drive CamSemi to Adopt a Full Mentor Graphics Tool Flow. Based on trust in Mentor Graphics IC design and verification tools and the exceptional support received from Mentor personnel, the global leader in power management ICs took the risk of switching their whole design flow just before a critical tapeout.

Download PDF (493kb)

Cambridge Semiconductor is leading the way in power management circuitry with their patented and proprietary technologies. This has a major implication for consumer products, where appliances such as televisions, phone chargers or video recorders will consume almost no power in standby mode.

The company’s sophisticated solutions and approach are helping many leading global electronics brands meet the most demanding energy-efficiency regulations for power supplies— including Energy Star 2.0 and the latest 5 star-rating scheme for cellular phone chargers—while reducing their design timescales and system costs. Beyond being more energy efficient, the technology is also lower cost than the current alternative. This means the company is poised to rapidly expand into global markets.

Unfortunately, the company’s IC design and verification tools were not keeping up with either the increased business or the increase in device complexity. CamSemi engineers could not verify chip designs to their own satisfaction because of increasing verification times. Their primary EDA tool vendor had little to offer as a solution, so they began exploring other options. Replacing one set of EDA tools with another isn’t as simple as it might seem. First, comparing feature-for-feature isn’t really practical. Each vendor may solve problems in very different ways, making it all but impossible to map functions and measure results “apples to apples.”

This effect trickles down to the way the tools are used. Whole subflows may need to be added or deleted. Doing so without risk requires a great deal of knowledge about both sets of tools (and the customer’s own special requirements). Perhaps more daunting is the challenge of changing people. Over time, designers learn what works in the existing design environment and adapt behavior to best suit the system. This behavior may become second nature. Introducing a new tool flow must not only support designs that were optimized for the old tools (being certain that no design intent is lost during transition), but also train designers on the benefits of the new flow, and new behavior.

Even though CamSemi used tools from a different EDA company for their IC design and verification flow, they were familiar with Mentor Graphics. Mentor Graphics field technical personnel saw CamSemi’s dilemma and offered VP of Engineering Nigel Heather an alternative. Questa® ADMS™ and the newly revamped IC Station could replace the entire analog/mixed signal (AMS) flow from top to bottom at a lower cost and with greater simulation throughput. The customer could potentially double verification throughput with no negative impact on quality of results.

The management at CamSemi was intrigued, but conscious of the risks. Mentor Graphics would have to prove to them that the results would be as good or better, and all design data could be maintained for reuse. If Mentor Graphics could do all of this without affecting productivity during the transition, CamSemi would shift to a full Mentor Graphics solution. Experience and Knowledge Bring out the Best of the Tools, the timing was difficult. CamSemi was working toward a tapeout, so there would be little time for pilot projects or benchmarking on nonproduction data.

The transition to the new flow would have to be smooth and have almost no impact on production schedules. Mentor Graphics Consulting Division dedicated an AMS expert to work onsite at CamSemi to make the transition successful until the tapeout was complete. The consultant, Amro Tork, worked closely with CamSemi and Mentor Graphics technologists to:

  • Implement a transition flow that maintained schematics and design information as he translated designs to the IC Station formats. He was also expected to keep the layout hierarchy using devices from the existing CamSemi technology libraries.
  • Tie Mentor Graphics tools to the data without any gaps in functionality.
  • Customize design kits.
  • Help validate simulation results.
  • Create training materials (both formal and informal) on the new flow for CamSemi designers.
  • Work side-by-side with designers as they took over responsibility for the new flow.

As this work was being done, process management steps were taken to anticipate any issues that might arise, addressing them before they became problems. With little time to waste, any potential trouble spots had to be addressed before they could affect production schedules.

The IC Station® design team won awards in recent years for product quality improvements and adding new features that increased productivity. Consultant Amro Tork knew that combining the strength of the new IC Station with Questa ADMS and Calibre® would be competitive to the market leading products. New features, especially an IC Station function to automate library translation, were extremely valuable during the introduction.

The conversion/migration flow was verified and used on CamSemi’s main Primary Side Sensing Logic chip design. The Questa ADMS–based solution provided almost twice the through put of the old tool and demonstrated that Eldo-based simulation could provide capabilities and features that would save the team time when developing their own results measurement scripts. The new flow actually caught two bugs that would have been missed by the old flow.

Mentor Graphics was able to support the newest CamSemi designs for no-load power chargers (mainly for cell phones), but also created a device generator that supports CamSemi’s high voltage devices—something they didn’t have with their existing tools. “Moving from a well entrenched design and verification environment to something new is an enormous task even when you’re not faced with an impending tapeout,” said John Greenwood, Analog Design Team Manager, CamSemi. “Mentor put a great deal of time into anticipating possible problems, and working to dismiss them before they could manifest themselves. This attention to detail was critical to the ultimate success of the replacement process.” Confidence in the migration process, and trust in Mentor Graphics as a business partner, resulted in Cambridge Semiconductor using the new flow for this project, and for two more that will be taking place in the coming months.

Moving from a well entrenched design and verification environment to something new is an enormous task even when you’re not faced with an impending tapeout. Mentor put a great deal of time into anticipating possible problems, and working to dismiss them before they could manifest themselves. This attention to detail was critical to the ultimate success of the replacement process.”

John Greenwood, Analog Design Team Manager, CamSemi

About CamSemi

CamSemi is the emerging leader in power management ICs for optimised, energy efficient, off-line power conversion. The company’s unique solutions and approach are helping many of the world’s top electronics brands to develop smaller, lighter and more energy-efficient, mains-powered products while also reducing their design timescales, system and manufacturing costs.

The company was founded to bring to market a new generation of sophisticated power management ICs that help manufacturers more easily meet the world’s increasing demand to save energy but at acceptable cost. CamSemi’s products are based on its portfolio of patented and proprietary technologies including intelligent control architectures and PowerBrane® ultra high voltage (UHV) process technology. These breakthrough approaches can benefit multiple markets, although initial products are targeted at the switch mode power supply and lighting sectors.

Online Chat