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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] |
Computer Memory
Computer memory stores information, such as data and programs, for immediate use in the computer. The term ''memory'' is often synonymous with the terms ''RAM,'' ''main memory,'' or ''primary storage.'' Archaic synonyms for main memory include ''core'' (for magnetic core memory) and ''store''. Main memory operates at a high speed compared to mass storage which is slower but less expensive per bit and higher in capacity. Besides storing opened programs and data being actively processed, computer memory serves as a Page cache, mass storage cache and write buffer to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it is not needed by running software. If needed, contents of the computer memory can be transferred to storage; a common way of doing this is through a memory management technique called ''virtual memory''. Modern computer memory is implemented as semiconductor memory, where data is stored within memory cell (com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NRAM Contact Point
NRAM may refer to: * 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 ..., a proprietary computer memory technology * Landmark Mortgages, formerly NRAM plc, a British asset holding and management company {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CNT Switch
CNT may refer to: Organized labor * ''Confederación Nacional del Trabajo'' (CNT), the National Confederation of Labor, a Spanish confederation of anarcho-syndicalist labor unions * ''Central Nacional de Trabajadores'' (CNT), the National Workers' Central (Paraguay), a national trade union center in Paraguay * '' Confédération nationale du travail'' (CNT-F), the National Confederation of Labour, a French anarcho-syndicalist union * ''Confédération Nigérienne du Travail'', the Nigerien Confederation of Labour, a trade union federation in Niger * '' Plenario Intersindical de Trabajadores - Convención Nacional de Trabajadores'' PIT-CNT, a national trade union center in Uruguay Science and technology * Carbon nanotube, an allotrope of carbon with a cylindrical nanostructure * Classical nucleation theory * Computer Network Technology Corporation, an enterprise acquired by McData in January 2005; see Ultra Network Technologies * Columbia Non-neutral Torus, a small stellarat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunnel Magnetoresistance
Tunnel magnetoresistance (TMR) is a magnetoresistance, magnetoresistive effect that occurs in a magnetic tunnel junction (MTJ), which is a component consisting of two ferromagnets separated by a thin Insulator (electrical), insulator. If the insulating layer is thin enough (typically a few nanometres), electrons can Quantum tunneling, tunnel from one ferromagnet into the other. Since this process is forbidden in classical physics, the tunnel magnetoresistance is a strictly Quantum mechanics, quantum mechanical phenomenon, and lies in the study of spintronics. Magnetic tunnel junctions are manufactured in thin film technology. On an industrial scale the film deposition is done by magnetron sputter deposition; on a laboratory scale molecular beam epitaxy, pulsed laser deposition and electron beam physical vapor deposition are also utilized. The junctions are prepared by photolithography. Phenomenological description The direction of the two magnetizations of the ferromagnetic film ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Tunnel Junctions
Tunnel magnetoresistance (TMR) is a magnetoresistive effect that occurs in a magnetic tunnel junction (MTJ), which is a component consisting of two ferromagnets separated by a thin insulator. If the insulating layer is thin enough (typically a few nanometres), electrons can tunnel from one ferromagnet into the other. Since this process is forbidden in classical physics, the tunnel magnetoresistance is a strictly quantum mechanical phenomenon, and lies in the study of spintronics. Magnetic tunnel junctions are manufactured in thin film technology. On an industrial scale the film deposition is done by magnetron sputter deposition; on a laboratory scale molecular beam epitaxy, pulsed laser deposition and electron beam physical vapor deposition are also utilized. The junctions are prepared by photolithography. Phenomenological description The direction of the two magnetizations of the ferromagnetic films can be switched individually by an external magnetic field. If the magnetiz ... [...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 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetoresistive Random-access Memory
Magnetoresistance is the tendency of a material (often Ferromagnetism, ferromagnetic) to change the value of its electrical resistance in an externally-applied magnetic field. There are a variety of effects that can be called magnetoresistance. Some occur in bulk non-magnetic metals and semiconductors, such as geometrical magnetoresistance, Shubnikov–de Haas effect, Shubnikov–de Haas oscillations, or the common positive magnetoresistance in metals. Other effects occur in magnetic metals, such as negative magnetoresistance in ferromagnets or anisotropic magnetoresistance (AMR). Finally, in multicomponent or multilayer systems (e.g. magnetic tunnel junctions), giant magnetoresistance (GMR), tunnel magnetoresistance (TMR), colossal magnetoresistance (CMR), and extraordinary magnetoresistance (EMR) can be observed. The first magnetoresistive effect was discovered in 1856 by William Thomson, 1st Baron Kelvin, William Thomson, better known as Lord Kelvin, but he was unable to lower t ... [...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 speeds 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 lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Hundreds of GB to a few TB of slow but non-volatile flash memory or "spinning platter" hard disk drive for long-term storage. For example, a university recommended students entering in 2015–2016 to have a PC with: : ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CPU Cache
A CPU cache is a hardware cache used by the central processing unit (CPU) of a computer to reduce the average cost (time or energy) to access data from the main memory. A cache is a smaller, faster memory, located closer to a processor core, which stores copies of the data from frequently used main memory locations. Most CPUs have a hierarchy of multiple cache levels (L1, L2, often L3, and rarely even L4), with different instruction-specific and data-specific caches at level 1. The cache memory is typically implemented with static random-access memory (SRAM), in modern CPUs by far the largest part of them by chip area, but SRAM is not always used for all levels (of I- or D-cache), or even any level, sometimes some latter or all levels are implemented with eDRAM. Other types of caches exist (that are not counted towards the "cache size" of the most important caches mentioned above), such as the translation lookaside buffer (TLB) which is part of the memory management unit (M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charge Pump
A charge pump is a kind of DC-to-DC converter that uses capacitors for energetic charge storage to raise or lower voltage. Charge-pump circuits are capable of high efficiencies, sometimes as high as 90–95%, while being electrically simple circuits. Description Charge pumps use some form of switching device to control the connection of a supply voltage across a load through a capacitor in a two stage cycle. In the first stage a capacitor is connected across the supply, charging it to that same voltage. In the second stage the circuit is reconfigured so that the capacitor is in series with the supply and the load. This doubles the voltage across the load - the sum of the original supply and the capacitor voltages. The pulsing nature of the higher voltage switched output is often smoothed by the use of an output capacitor. An external or secondary circuit drives the switching, typically at tens of kilohertz up to several megahertz. The high frequency minimizes the amount of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
