Advanced tools of VLSI

Advanced tools

Advanced tools for VLSI design[Photo][Photo]A VLSI VL82C106 Super I/Ochip.The original business plan was to be a contract wafer fabrication company, but the venture investors wanted the company to develop IC design tools to help fill the foundry.Thanks to its Cal Tech and UC Berkeley students, VLSI was an important pioneer in the electronic design automation industry. It offered a sophisticated package of tools, originally based on the 'lambda-based' design style advocated by Carver Mead and Lynn Conway.VLSI became the an early vendor of standard cell (cell-based technology) to the merchant market in the early 80s where the other ASIC-focused company, LSI Logic, was a leader in gate arrays. Prior to VLSI's cell-based offering, the technology had been primarily available only within large vertically integrated companies with semiconductor units such as AT&T and IBM.VLSI's design tools eventually included not only design entry and simulation but eventually cell-based routing (chip compiler), a datapath compiler, SRAM and ROM compilers, and a state machine compiler. The tools were an integrated design solution for IC design and not just point tools, or more general purpose system tools. A designer could edit transistor-level polygons and/or logic schematics, then run DRC and LVS, extract parasitics from the layout and run Spice simulation, then back-annotate the timing or gate size changes into the logic schematic database. Characterization tools were integrated to generate FrameMaker Data Sheets for Libraries. VLSI eventually spun-off the CAD and Library operation into Compass Design Automation but it never reached IPO before it was purchased by Avanti Corp.VLSI's physical design tools were critical not only to its ASIC business, but also in setting the bar for the commercial EDA industry. When VLSI and its main ASIC competitor, LSI Logic, were establishing the ASIC industry, commercially-available tools could not deliver the productivity necessary to support the physical design of hundreds of ASIC designs each year without the deployment of a substantial number of layout engineers. The companies' development of automated layout tools was a rational "make because there's nothing to buy" decision.