机械自动化类毕业设计外文翻译--电子设计自动化(编辑修改稿)

机械自动化类毕业设计外文翻译--电子设计自动化(编辑修改稿)内容摘要：

plicated and the number of possible test vectors mushrooms. So recently, electronic design automation panies have been turning to model checking to prove that designs are correctly done. The sticking point with model checking is its great difficulty of use. It is not for most engineers, said Simon Napper, chief operating officer OF Innologic Systems Inc., San Jose, Calif. The usage model is very difficultit checks properties. But the designer isn39。 t familiar with what P property ishe is used to simulation and static timing. As a remedy, InnoLogic developed a symbolic simulation tool, which blends simulation and formal verification. It is a Virology simulator except instead of sending Is and Os through the logic, the too1 propagates symbol or symbols plus binary user gains improved functional coverage dong with much faster verification. To illustrate, to pletely verify a fourbit adder would require 256 binary vectorsand take 256 simulation cycles. With symbols, it takes just one cycle. Just as with formal verification, there are limits to the plexity of the circuits that symbolic simulation can pletely verily. Both have trouble with multipliers, for example. A model checker will grind and grind and never produce a result, explained Napper. But in our tool we take some symbol inputs and switch them to binary values, that reduces the job from a 32 to a 16bit multiplier. And we report to the user that we were able to verify the upper the operands. InnoLogic has announced two Versifies of symbolic simulation. ESI39。 XV verifies designs written in Virology. EXPCV is meant for custom designs and memory blocks. THE TIME IS RIGHT Though the design of ICs with semiconductor geometries below pm face challenges throughout development, some of the biggest hurdles occur during physical design, when the gates are placed on the chip and the interconnects are routed between them Problems occur here for a number of reasons. First, the capacitance, resistance, and inductance of the interconnects cannot be ignored, as they were in older, larger technologies. Crosstalk between interconnects。 now closer together, must also be controlled. Several iterations through synthesis and placement may be necessary to achieve the required timing, if it can be acplished at all. The solution proposed by Monterey Design Systems Inc., Sunnyvale, Calif., is called global design technology. This proprietary puting approach simultaneously explores, analyzes, and optimizes all aspects of the physical design. The tint product containing the technology is Dolphin, which was announced in April of last year. Dolphin simultaneously places and router each gate and flipflop using the results or the analysis and maintaining all specified constraints. (Most place androute tools sequentially analyze the layout for each type of constraint.) It performs timing and logic optimization for every placement move. Timing closure is top priority for developers of the Blast Fusion physical design system from Magma Design Automations., Cupertino, Calif. Its methodology, called FixedTi ming, brings timing within specified limits without iterating between synthesis and physical design .Basically, he approach fixes timing first, then adjusts cell sizes to achieve the timing requirements. Varying the cell sizes always he tool to supply the right drive strength or the load. EDA ON THE WEB As established electronic design automation panies try to sort out how to utilize the inter in their product Inks, smaller, more agile panies and startups arc coining up with innovative products and services, mainly in the areas or design management. A pioneer in this area is Synchronicity Inc., a virtual pany headquartered in Marlboro, Mass. Synchronicity is now being joined by other panies seeking to use the inter to advantage. The concern of , Milpitas, Calif a provider of We bbased engineering tools 39。 for。 design automation, is the extraction of useful information about ICs, chip sets, and boards from suppliers39。 Web sites. The issue, according to Michael Bitzko, president of the pany, is that designers of products based on there ponents need to be able to obtain information about them quickly and route it to their engineering, manufacturing, and procurement departments as quickly as possible. In a nutshell,” said Bitzko, people used to take weeks to get data sheets. Then along cane the Web and PDFformatted docume。