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JEDEC Memory Standards
The JEDEC memory standards are the specifications for semiconductor memory circuits and similar storage devices promulgated by the Joint Electron Device Engineering Council (JEDEC) Solid State Technology Association, a semiconductor trade and engineering standardization organization. JEDEC Standard 100B.01 specifies common terms, units, and other definitions in use in the semiconductor industry. JESC21-C specifies semiconductor memories from the 256 bit static RAM to DDR4 SDRAM modules. JEDEC standardization goals The Joint Electron Device Engineering Council characterizes its standardization efforts as follows: JEDEC Standard 100B.01 The December 2002 JEDEC Standard 100B.01 is entitled ''Terms, Definitions, and Letter Symbols for Microcomputers, Microprocessors, and Memory Integrated Circuits''. The purpose of the standard is to promote the uniform use of symbols, abbreviations, terms, and definitions throughout the semiconductor industry. Units of information The specif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint Electron Device Engineering Council
A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw-Hill Connect. Webp.274/ref> They are constructed to allow for different degrees and types of movement. Some joints, such as the knee, elbow, and shoulder, are self-lubricating, almost frictionless, and are able to withstand compression and maintain heavy loads while still executing smooth and precise movements. Other joints such as sutures between the bones of the skull permit very little movement (only during birth) in order to protect the brain and the sense organs. The connection between a tooth and the jawbone is also called a joint, and is described as a fibrous joint known as a gomphosis. Joints are classified both structurally and functionally. Classification The number of joints depends on if sesamoids are included, age of the h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random Access Memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A Random access, random-access memory device allows data items to be read (computer), read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks, CD-RWs, DVD-RWs and the older Magnetic tape data storage, magnetic tapes and drum memory), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement. RAM contains multiplexer, multiplexing and demultiplexing circuitry, to connect the data lines to the addressed storage for reading or writing the entry. Usually more than one bit of storage is accessed by the same address, and RAM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DDR4 SDRAM
Double Data Rate 4 Synchronous Dynamic Random-Access Memory (DDR4 SDRAM) is a type of synchronous dynamic random-access memory with a high bandwidth (" double data rate") interface. Released to the market in 2014, it is a variant of dynamic random-access memory (DRAM), of which some have been in use since the early 1970s, and a higher-speed successor to the DDR2 and DDR3 technologies. DDR4 is not compatible with any earlier type of random-access memory (RAM) due to different signaling voltage and physical interface, besides other factors. DDR4 SDRAM was released to the public market in Q2 2014, focusing on ECC memory, while the non-ECC DDR4 modules became available in Q3 2014, accompanying the launch of Haswell-E processors that require DDR4 memory. Features The primary advantages of DDR4 over its predecessor, DDR3, include higher module density and lower voltage requirements, coupled with higher data rate transfer speeds. The DDR4 standard allows for DIMMs of up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byte
The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures. To disambiguate arbitrarily sized bytes from the common 8-bit definition, network protocol documents such as The Internet Protocol () refer to an 8-bit byte as an octet. Those bits in an octet are usually counted with numbering from 0 to 7 or 7 to 0 depending on the bit endianness. The first bit is number 0, making the eighth bit number 7. The size of the byte has historically been hardware-dependent and no definitive standards existed that mandated the size. Sizes from 1 to 48 bits have been used. The six-bit character code was an often-used implementation in early encoding systems, and computers using six-bit and nine-bit bytes were common in the 1960s. These systems often had memory words ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilo-
Kilo is a decimal unit prefix in the metric system denoting multiplication by one thousand (103). It is used in the International System of Units, where it has the symbol k, in lowercase. The prefix ''kilo'' is derived from the Greek word (), meaning "thousand". In 19th century English it was sometimes spelled chilio, in line with a puristic opinion by Thomas Young. As an opponent of suggestions to introduce the metric system in Britain, he qualified the nomenclature adopted in France as barbarous. Examples * one kilogram (kg) is 1000 grams * one kilometre (km) is 1000 metres * one kilojoule (kJ) is 1000 joules * one kilolitre (kL) is 1000 litres * one kilobaud (kBd) is 1000 baud * one kilohertz (kHz) is 1000 hertz * one kilobit (kb) is 1000 bits * one kilobyte (kB) is 1000 bytes * one kiloohm is (kΩ) is 1000 ohms * one kilosecond (ks) is 1000 seconds *one kilotonne (kt) is 1000 tonnes By extension, currencies are also sometimes preceded by the prefix kilo-: * one kil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mega-
Mega is a metric prefix, unit prefix in metric systems of units denoting a factor of one million (106 or 1000000 (number), ). It has the unit symbol M. It was confirmed for use in the International System of Units (SI) in 1960. ''Mega'' comes from grc, μέγας, mégas, great. Common examples of usage * Megapixel: 1 million pixels in a digital camera * One megatonne of TNT equivalent amounts to approx. 4 petajoules and is the approximate energy released on igniting one million tonnes of TNT. The unit is often used in measuring the explosive power of nuclear weapons. * Megahertz: frequency of electromagnetic radiation for radio and television broadcasting, GSM, etc. 1 MHz = 1,000,000 Hertz, Hz. * Megabyte: unit of information equal to one million bytes (SI standard). * Megawatt: equal to one million watts of power. It is commonly used to measure the output of power plants, as well as the power consumption of electric locomotives, data centers, and other entities that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giga-
Giga ( or ) is a unit prefix in the metric system denoting a factor of a short-scale billion or long-scale milliard (109 or ). It has the symbol G. ''Giga'' is derived from the Greek word (''gígas''), meaning "giant". The ''Oxford English Dictionary'' reports the earliest written use of ''giga'' in this sense to be in the Reports of the IUPAC 14th Conférence Internationale de Chimie in 1947: "The following prefixes to abbreviations for the names of units should be used: G giga 109×." When referring to information units in computing, such as gigabyte, giga may sometimes mean (230); this causes ambiguity. Standards organizations discourage this and use giga- to refer to 109 in this context too. ''Gigabit'' is only rarely used with the binary interpretation of the prefix. The binary prefix '' gibi'' has been adopted for 230, while reserving ''giga'' exclusively for the metric definition. Pronunciation In English, the prefix ''giga'' can be pronounced (a hard ''g'' as in ''gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Prefixes
A binary prefix is a unit prefix for multiples of units. It is most often used in data processing, data transmission, and digital information, principally in association with the bit and the byte, to indicate multiplication by a power of 2. As shown in the table to the right there are two sets of symbols for binary prefixes, one set established by International Electrotechnical Commission (IEC) and several other standards and trade organizations using two-letter symbols, e.g. ''Mi'' indicating with a second set established by semiconductor industry convention using one-letter symbols, e.g., ''M'' also indicating . In most contexts, industry uses the multipliers ''kilo'' (''k''), ''mega'' (''M''), ''giga'' (''G''), etc., in a manner consistent with their meaning in the International System of Units (SI), namely as powers of 1000. For example, a 500-gigabyte hard disk holds bytes, and a 1 Gbit/s (gigabit per second) Ethernet connection transfers data at nominal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serial Communication
In telecommunication and data transmission, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels. Serial communication is used for all long-haul communication and most computer networks, where the cost of cable and synchronization difficulties make parallel communication impractical. Serial computer buses are becoming more common even at shorter distances, as improved signal integrity and transmission speeds in newer serial technologies have begun to outweigh the parallel bus's advantage of simplicity (no need for serializer and deserializer, or SerDes) and to outstrip its disadvantages (clock skew, interconnect density). The migration from PCI to PCI Express is an example. Cables Many serial communication systems were originally designed to transfer data over relatively ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CAS Latency
Column Address Strobe (CAS) latency, or CL, is the delay in clock cycles between the READ command and the moment data is available. In asynchronous DRAM, the interval is specified in nanoseconds (absolute time). In synchronous DRAM, the interval is specified in clock cycles. Because the latency is dependent upon a number of clock ticks instead of absolute time, the actual time for an SDRAM module to respond to a CAS event might vary between uses of the same module if the clock rate differs. RAM operation background Dynamic RAM is arranged in a rectangular array. Each row is selected by a horizontal ''word line''. Sending a logical high signal along a given row enables the MOSFETs present in that row, connecting each storage capacitor to its corresponding vertical ''bit line''. Each bit line is connected to a ''sense amplifier'' that amplifies the small voltage change produced by the storage capacitor. This amplified signal is then output from the DRAM chip as well as driven ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEC 60027
IEC 60027 (formerly IEC 27) is a technical international standard for letter symbols published by the International Electrotechnical Commission (IEC), comprising the following parts: * IEC 60027-1: General * IEC 60027-2: Telecommunications and electronics * IEC 60027-3: Logarithmic and related quantities, and their units * IEC 60027-4: Symbols for quantities to be used for rotating electrical machines * IEC 60027-6: Control technology * IEC 60027-7: Physiological quantities and units A closely related international standard on quantities and units is ISO 31. The ISO 31 and IEC 60027 Standards are being revised by the two standardization organizations in collaboration. The revised harmonized standard is known as ISO/IEC 80000, Quantities and units. It supersedes both ISO 31 and part of IEC 60027. IEC 60027-2 IEC 60027-2 Amendment 2, as published in January 1999, was the first international standard defining the binary prefixes, as proposed by International Electrotechnical Commiss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEC 80000-13
ISO 80000 or IEC 80000 is an international standard introducing the International System of Quantities (ISQ). It was developed and promulgated jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It serves as a style guide for the use of physical quantities and units of measurement, formulas involving them, and their corresponding units, in scientific and educational documents for worldwide use. The ISO/IEC 80000 family of standards was completed with the publication of Part 1 in November 2009. Overview , ISO/IEC 80000 comprises 13 parts, two of which (parts 6 and 13) were developed by IEC and the remaining 11 were developed by ISO, with a further three parts (15, 16 and 17) under development. Part 14 was withdrawn. Subject areas The 80000 standard currently has 13 parts. Part 1: General ISO 80000-1:2009 replaces ISO 31-0:1992 and ISO 1000:1992. It gives general information and definitions con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
