Over the past three decades, we have witnessed the remarkable growth of the semiconductor industry from the invention of the transistor to an industry that is all-pervasive in its effect on modern life. LSI technology is visible everywhere; in our watches, calculators, automobiles, appliances, telephones, televisions, weapons, computers, and even our toys. Each time geometries are reduced by half, circuit complexity has potentially increased by four. MOORE’s law shows a resultant doubling of circuit complexity each year. The profusion of new products using this technology are the direct result of a designer’s ability to economically mold his creative ideas to the latest semiconductor process. The success of microprocessors is an excellent example of an approach which broadens the number of potential applications while reducing design cost.