The NVAX CPU Chip: Design Challenges, Methods, and CAD Tools

The NVAX CPU chip is a 1.3 million transistor, VAX microprocessor designed in Digital's 0.75-micrometer CMOS-4 technology. It has a typical cycle time of 12 ns under worst-case operating conditions. The goal of the chip design team was to design a high-performance, robust, and reliable chip, within the constraints of a short schedule. Design strategies were developed to achieve this goal, including organization of a chip design flow and new implementation and verification methods. New proprietary CAD tools also played important roles in the chip development.