High Performance Memories

Die Bandbreite und Zugriffszeit traditioneller DRAMs reicht nicht mehr aus, um mit der Geschwindigkeit moderner Mikroprozessoren Schritt zu halten. Daher baut man verstärkt Hochleistungs-Speicherchips, deren neue Generation das Thema dieses Buches bildet. Die Autorin, eine international anerkannte Spezialistin, diskutiert objektiv und herstellerunabhängig Technologien wie DDR DRAMs, CiDDR DRAMs, SL=DRAM, Direct Rambus, SSTL Interfaces und MP-DRAMs. Der aktuellste verfügbare Beitrag zu einem enorm wichtigen Thema! (12/98)

Are memory applications more critical than they have been in the past? Yes, but even more critical is the number of designs and the sheer number of bits on each design. It is assured that catastrophes, which were avoided in the past because memories were small, will easily occur if the design and test engineers do not do their jobs very carefully. High Performance Memory Testing: Design Principles, Fault Modeling and Self Test is based on the author's 20 years of experience in memory design, memory reliability development and memory self test. High Performance Memory Testing: Design Principles, Fault Modeling and Self Test is written for the professional and the researcher to help them understand the memories that are being tested.

Traditional Dynamic Random Access Memory Modules, or DRAMs, no longer have adequate bandwidth and access time to keep up with the speed of current microprocessors. In order to solve this problem, many work stations and mainframe manufacturers are starting to use high speed memories, which are memory technologies that improve the speed and efficiency of microprocessors. It is expected that high speed memories will be in widespread use within a few years.

Emerging Memories: Technologies and Trends attempts to provide background and a description of the basic technology, function and properties of emerging as well as discussing potentially suitable applications. This book explores a range of new memory products and technologies. The concept for some of these memories has been around for years. A few completely new. Some involve materials that have been in volume production in other type of devices for some time. Ferro-electrics, for example, have been used in capacitors for more than 30 years. In addition to looking at using known devices and materials in novel ways, there are new technologies being investigated such as DNA memories, light memories, molecular memories, and carbon nanotube memories, as well as the new polymer memories which hold the potential for the significant manufacturing reduction. Emerging Memories: Technologies and Trends is a useful reference for the professional engineer in the semiconductor industry.

The State of Memory Technology Over the past decade there has been rapid growth in the speed of micropro cessors. CPU speeds are approximately doubling every eighteen months, while main memory speed doubles about every ten years. The International Tech nology Roadmap for Semiconductors (ITRS) study suggests that memory will remain on its current growth path. The ITRS short-and long-term targets indicate continued scaling improvements at about the current rate by 2016. This translates to bit densities increasing at two times every two years until the introduction of 8 gigabit dynamic random access memory (DRAM) chips, after which densities will increase four times every five years. A similar growth pattern is forecast for other high-density chip areas and high-performance logic (e.g., microprocessors and application specific inte grated circuits (ASICs)). In the future, molecular devices, 64 gigabit DRAMs and 28 GHz clock signals are targeted. Although densities continue to grow, we still do not see significant advances that will improve memory speed. These trends have created a problem that has been labeled the Memory Wall or Memory Gap.

Semiconductor Memories provides in-depth coverage in the areas of design for testing, fault tolerance, failure modes and mechanisms, and screening and qualification methods including. * Memory cell structures and fabrication technologies. * Application-specific memories and architectures. * Memory design, fault modeling and test algorithms, limitations, and trade-offs. * Space environment, radiation hardening process and design techniques, and radiation testing. * Memory stacks and multichip modules for gigabyte storage.

Kevin Zhang Advancement of semiconductor technology has driven the rapid growth of very large scale integrated (VLSI) systems for increasingly broad applications, incl- ing high-end and mobile computing, consumer electronics such as 3D gaming, multi-function or smart phone, and various set-top players and ubiquitous sensor and medical devices. To meet the increasing demand for higher performance and lower power consumption in many different system applications, it is often required to have a large amount of on-die or embedded memory to support the need of data bandwidth in a system. The varieties of embedded memory in a given system have alsobecome increasingly more complex, ranging fromstatictodynamic and volatile to nonvolatile. Among embedded memories, six-transistor (6T)-based static random access memory (SRAM) continues to play a pivotal role in nearly all VLSI systems due to its superior speed and full compatibility with logic process technology. But as the technology scaling continues, SRAM design is facing severe challenge in mainta- ing suf?cient cell stability margin under relentless area scaling. Meanwhile, rapid expansion in mobile application, including new emerging application in sensor and medical devices, requires far more aggressive voltage scaling to meet very str- gent power constraint. Many innovative circuit topologies and techniques have been extensively explored in recent years to address these challenges.

Is your memory hierarchy stopping your microprocessor from performing at the high level it should be? Memory Systems: Cache, DRAM, Disk shows you how to resolve this problem. The book tells you everything you need to know about the logical design and operation, physical design and operation, performance characteristics and resulting design trade-offs, and the energy consumption of modern memory hierarchies. You learn how to to tackle the challenging optimization problems that result from the side-effects that can appear at any point in the entire hierarchy.As a result you will be able to design and emulate the entire memory hierarchy. Understand all levels of the system hierarchy -Xcache, DRAM, and disk. Evaluate the system-level effects of all design choices. Model performance and energy consumption for each component in the memory hierarchy.