Design Considerations for Semiconductor Ramdom Access Memory Systems

Random access semiconductor memory systerm components available today reflect a broad spectrum of engineering, financial and managerial judgment. Each of the products was intended to satisfy the performance and cost goals of a particular segment of the memory market. The decisions which were made regarding technology to be used, chip density, package density, package type, electrical performance and environmental performance, reflect the weighted factors of market segment need versus investment required. The resulting product is in many cases a compromise. For example, a lower chip density may result in lower cost per bit at the chip level due to higher yields. However, higher chip densities, inherent when decoding is on the chip, may be required due to the lack of a package with enough leads to accommodate a non-decoded chip. The assumption is that need to capitalize a new package production line represents higher financial risk than that which results from the lower yields at the chip level.