|
Universal Memory
Universal memory refers to a computer data storage device combining the cost benefits of DRAM, the speed of SRAM, the non-volatility of flash memory along with infinite durability, and longevity. Such a device, if it ever becomes possible to develop, would have a far-reaching impact on the computer market. Some doubt that such a type of memory will ever be possible. Computers, for most of their recent history, have depended on several different data storage technologies simultaneously as part of their operation. Each one operates at a level in the memory hierarchy where another would be unsuitable. A personal computer might include a few megabytes of fast but volatile and expensive SRAM as the CPU cache, several gigabytes of slower DRAM for program memory, and 128 GB-8 TB of the slow but non-volatile flash memory or 1-10 terabytes of "spinning platters" hard disk drive for long-term storage. For example, a university recommended students entering in 2015–2016 to have a PC w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Data Storage
Computer data storage is a technology consisting of computer components and Data storage, recording media that are used to retain digital data (computing), data. It is a core function and fundamental component of computers. The central processing unit (CPU) of a computer is what manipulates data by performing computations. In practice, almost all computers use a memory hierarchy, storage hierarchy, which puts fast but expensive and small storage options close to the CPU and slower but less expensive and larger options further away. Generally, the fast volatile technologies (which lose data when off power) are referred to as "memory", while slower persistent technologies are referred to as "storage". Even the first computer designs, Charles Babbage's Analytical Engine and Percy Ludgate's Analytical Machine, clearly distinguished between processing and memory (Babbage stored numbers as rotations of gears, while Ludgate stored numbers as displacements of rods in shuttles). Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid-state Drive
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is also sometimes called a semiconductor storage device, a solid-state device or a solid-state disk, even though SSDs lack the physical spinning disks and movable read–write heads used in hard disk drives (HDDs) and floppy disks. SSD also has rich internal parallelism for data processing. In comparison to hard disk drives and similar electromechanical media which use moving parts, SSDs are typically more resistant to physical shock, run silently, and have higher input/output rates and lower latency. SSDs store data in semiconductor cells. cells can contain between 1 and 4 bits of data. SSD storage devices vary in their properties according to the number of bits stored in each cell, with single-bit cells ("Single Level Cells" or "SLC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid-state Computer Storage Media
Solid state, or solid matter, is one of the four fundamental states of matter. Solid state may also refer to: Electronics * Solid-state electronics, circuits built of solid materials * Solid state ionics, study of ionic conductors and their uses Music * Solid State Records, a Christian music label * Solid State Records (jazz label), active in the 1960s * Solid State, a music group featuring DJ Dextrous * ''Solid State'' (Leon Russell album), 1984 * ''Solid State'' (Jonathan Coulton album), 2017 * ''Solid State'', an album by Sam Phillips Science * Solid-state chemistry, the study of the synthesis, structure, and properties of solid phase materials * Solid-state physics Solid-state physics is the study of rigid matter, or solids, through methods such as quantum mechanics, crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics. Solid-state physics studies how the l ..., the study of rigid matter, or solids, through method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memristor
A memristor (; a portmanteau of ''memory resistor'') is a non-linear two-terminal electrical component relating electric charge and magnetic flux linkage. It was described and named in 1971 by Leon Chua, completing a theoretical quartet of fundamental electrical components which comprises also the resistor, capacitor and inductor. Chua and Kang later generalized the concept to memristive systems. Such a system comprises a circuit, of multiple conventional components, which mimics key properties of the ideal memristor component and is also commonly referred to as a memristor. Several such memristor system technologies have been developed, notably ReRAM. The identification of memristive properties in electronic devices has attracted controversy. Experimentally, the ideal memristor has yet to be demonstrated. As a fundamental electrical component Chua in his 1971 paper identified a theoretical symmetry between the non-linear resistor (voltage vs. current), non-linear capacit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nano-RAM
Nano-RAM is a proprietary computer memory technology from the company Nantero. It is a type of non-volatile memory, nonvolatile random-access memory based on the position of carbon nanotubes deposited on a chip-like substrate. In theory, the small size of the nanotubes allows for very high density memories. Nantero also refers to it as NRAM. Technology The first generation Nantero NRAM technology was based on a three-terminal semiconductor device where a third terminal is used to switch the memory cell between memory states. The second generation NRAM technology is based on a two-terminal memory cell. The two-terminal cell has advantages such as a smaller cell size, better scalability to sub-20 nm nodes (see semiconductor device fabrication), and the ability to Passivation (chemistry), passivate the memory cell during fabrication. In a non-woven fabric matrix of carbon nanotubes (CNTs), crossed nanotubes can either be touching or slightly separated depending on their positio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RRAM
Resistive random-access memory (ReRAM or RRAM) is a type of non-volatile (NV) random-access memory, random-access (RAM) computer memory that works by changing the resistance across a dielectric solid-state material, often referred to as a memristor. ReRAM bears some similarities to Programmable metallization cell, conductive-bridging RAM (CBRAM) and phase-change memory (PCM). CBRAM involves one electrode providing ions that dissolve readily in an electrolyte material, while PCM involves generating sufficient Joule heating to effect amorphous-to-crystalline or crystalline-to-amorphous phase changes. By contrast, ReRAM involves generating defects in a thin oxide layer, known as oxygen vacancies (oxide bond locations where the oxygen has been removed), which can subsequently charge and drift under an electric field. The motion of oxygen ions and vacancies in the oxide would be analogous to the motion of electrons and holes in a semiconductor. Although ReRAM was initially seen as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programmable Metallization Cell
The programmable metallization cell, or PMC, is a non-volatile computer memory developed at Arizona State University. PMC, a technology developed to replace the widely used flash memory, providing a combination of longer lifetimes, lower power, and better memory density. Infineon Technologies, who licensed the technology in 2004, refers to it as conductive-bridging RAM, or CBRAM. CBRAM became a registered trademark of Adesto Technologies in 2011. NEC has a variant called "Nanobridge" and Sony calls their version "electrolytic memory". Description PMC is a two terminal resistive memory technology developed at Arizona State University. PMC is an electrochemical metallization memory that relies on redox reactions to form and dissolve a conductive filament. The state of the device is determined by the resistance across the two terminals. The existence of a filament between the terminals produces a low resistance state (LRS) while the absence of a filament results in a high r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase-change Memory
Phase-change memory (also known as PCM, PCME, PRAM, PCRAM, OUM (ovonic unified memory) and C-RAM or CRAM (chalcogenide RAM)) is a type of non-volatile random-access memory. PRAMs exploit the unique behaviour of chalcogenide glass. In PCM, heat produced by the passage of an electric current through a heating element generally made of titanium nitride is used to either quickly heat and quench the glass, making it amorphous, or to hold it in its crystallization temperature range for some time, thereby switching it to a crystalline state. PCM also has the ability to achieve a number of distinct intermediary states, thereby having the ability to hold multiple bits in a single cell, but the difficulties in programming cells in this way has prevented these capabilities from being implemented in other technologies (most notably flash memory) with the same capability. Recent research on PCM has been directed towards attempting to find viable material alternatives to the phase-change materi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferroelectric RAM
Ferroelectric RAM (FeRAM, F-RAM or FRAM) is a random-access memory similar in construction to DRAM but using a ferroelectric layer instead of a dielectric layer to achieve non-volatility. FeRAM is one of a growing number of alternative non-volatile random-access memory technologies that offer the same functionality as flash memory. An FeRAM chip contains a thin film of ferroelectric material, often lead zirconate titanate, commonly referred to as PZT. The atoms in the PZT layer change polarity in an electric field, thereby producing a power-efficient binary switch. However, the most important aspect of the PZT is that it is not affected by power disruption or magnetic interference, making FeRAM a reliable nonvolatile memory. FeRAM's advantages over Flash include: lower power usage, faster write performance and a much greater maximum read/write endurance (about 1010 to 1015 cycles). FeRAMs have data retention times of more than 10 years at +85 °C (up to many decades at lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racetrack Memory
Racetrack memory or domain-wall memory (DWM) is an experimental non-volatile memory device under development at IBM's Almaden Research Center by a team led by physicist Stuart Parkin. In early 2008, a 3-bit version was successfully demonstrated. If it were to be developed successfully, racetrack memory would offer storage density higher than comparable solid-state memory devices like flash memory. Description Racetrack memory uses a spin-coherent electric current to move magnetic domains along a nanoscopic permalloy wire about 200 nm across and 100 nm thick. As current is passed through the wire, the domains pass by magnetic read/write heads positioned near the wire, which alter the domains to record patterns of bits. A racetrack memory device is made up of many such wires and read/write elements. In general operational concept, racetrack memory is similar to the earlier bubble memory of the 1960s and 1970s. Delay-line memory, such as mercury delay lines of the 1940 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bubble Memory
Bubble memory is a type of non-volatile computer memory that uses a thin film of a magnetic material to hold small magnetized areas, known as ''bubbles'' or ''domains'', each storing one bit of data. The material is arranged to form a series of parallel tracks that the bubbles can move along under the action of an external magnetic field. The bubbles are read by moving them to the edge of the material, where they can be read by a conventional magnetic pickup, and then rewritten on the far edge to keep the memory cycling through the material. In operation, bubble memories are similar to delay-line memory systems. Bubble memory started out as a promising technology in the 1970s, offering memory density of an order similar to hard drives, but performance more comparable to core memory, while lacking any moving parts. This led many to consider it a contender for a "universal memory" that could be used for all storage needs. The introduction of dramatically faster semiconductor me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRAM
Magnetoresistive random-access memory (MRAM) is a type of non-volatile random-access memory which stores data in magnetic domains. Developed in the mid-1980s, proponents have argued that magnetoresistive RAM will eventually surpass competing technologies to become a dominant or even universal memory. Currently, memory technologies in use such as flash RAM and DRAM have practical advantages that have so far kept MRAM in a niche role in the market. Description Unlike conventional RAM chip technologies, data in MRAM is not stored as electric charge or current flows, but by magnetic storage elements. The elements are formed from two ferromagnetic plates, each of which can hold a magnetization, separated by a thin insulating layer. One of the two plates is a permanent magnet set to a particular polarity; the other plate's magnetization can be changed to match that of an external field to store memory. This configuration is known as a magnetic tunnel junction and is the simplest st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
