高速电路板设计技术EApplication Notes High-Speed Board Design Techniques INTRODUCTION The most important factor in the design of many systems today is speed. 66-MHz thru 200-MHz processors are common; 233 and 266-MHz processors are becoming readily available. The demand for high speed results from: a) the requirement that systems perform complex tasks in a time frame considered comfortable by humans; and b) the ability of component manufacturers to produce high-speed devices. An example of a) is the large amount of information that must be processed to perform even the most rudimentary computer animation. Currently, Programmable Array Logic (PAL) devices are available with propagation delays of 4.5 ns, and complex PLDs such as MACH have propagation delays of 5 ns. While this might seem fast, it is not the pr……