1.
IBM
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International Business Machines Corporation is an American multinational technology company headquartered in Armonk, New York, United States, with operations in over 170 countries. The company originated in 1911 as the Computing-Tabulating-Recording Company and was renamed International Business Machines in 1924, IBM manufactures and markets computer hardware, middleware and software, and offers hosting and consulting services in areas ranging from mainframe computers to nanotechnology. IBM is also a research organization, holding the record for most patents generated by a business for 24 consecutive years. IBM has continually shifted its business mix by exiting commoditizing markets and focusing on higher-value, also in 2014, IBM announced that it would go fabless, continuing to design semiconductors, but offloading manufacturing to GlobalFoundries. Nicknamed Big Blue, IBM is one of 30 companies included in the Dow Jones Industrial Average and one of the worlds largest employers, with nearly 380,000 employees. Known as IBMers, IBM employees have been awarded five Nobel Prizes, six Turing Awards, ten National Medals of Technology, in the 1880s, technologies emerged that would ultimately form the core of what would become International Business Machines. On June 16,1911, their four companies were amalgamated in New York State by Charles Ranlett Flint forming a fifth company, the Computing-Tabulating-Recording Company based in Endicott, New York. The five companies had 1,300 employees and offices and plants in Endicott and Binghamton, New York, Dayton, Ohio, Detroit, Michigan, Washington, D. C. and Toronto. They manufactured machinery for sale and lease, ranging from commercial scales and industrial time recorders, meat and cheese slicers, to tabulators and punched cards. Thomas J. Watson, Sr. fired from the National Cash Register Company by John Henry Patterson, called on Flint and, Watson joined CTR as General Manager then,11 months later, was made President when court cases relating to his time at NCR were resolved. Having learned Pattersons pioneering business practices, Watson proceeded to put the stamp of NCR onto CTRs companies and his favorite slogan, THINK, became a mantra for each companys employees. During Watsons first four years, revenues more than doubled to $9 million, Watson had never liked the clumsy hyphenated title of the CTR and in 1924 chose to replace it with the more expansive title International Business Machines. By 1933 most of the subsidiaries had been merged into one company, in 1937, IBMs tabulating equipment enabled organizations to process unprecedented amounts of data, its clients including the U. S. During the Second World War the company produced small arms for the American war effort, in 1949, Thomas Watson, Sr. created IBM World Trade Corporation, a subsidiary of IBM focused on foreign operations. In 1952, he stepped down after almost 40 years at the company helm, in 1957, the FORTRAN scientific programming language was developed. In 1961, IBM developed the SABRE reservation system for American Airlines, in 1963, IBM employees and computers helped NASA track the orbital flight of the Mercury astronauts. A year later it moved its headquarters from New York City to Armonk. The latter half of the 1960s saw IBM continue its support of space exploration, on April 7,1964, IBM announced the first computer system family, the IBM System/360
2.
General Electric
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General Electric, often abbreviated as GE, is an American multinational conglomerate corporation incorporated in New York and headquartered in Boston, Massachusetts. In 2011, GE ranked among the Fortune 500 as the 68th-largest firm in the U. S. by gross revenue, as of 2012, the company was listed the fourth-largest in the world among the Forbes Global 2000, further metrics being taken into account. The Nobel Prize has twice been awarded to employees of General Electric, Irving Langmuir in 1932, on January 13,2016, it was announced that GE will be moving its corporate headquarters from Fairfield, Connecticut to the South Boston Waterfront neighborhood of Boston, Massachusetts. The first group of workers arrived in the summer of 2016, morgan and the Vanderbilt family for Edisons lighting experiments. The new company also acquired Sprague Electric Railway & Motor Company in the same year, both plants continue to operate under the GE banner to this day. The company was incorporated in New York, with the Schenectady plant used as headquarters for years thereafter. Around the same time, General Electrics Canadian counterpart, Canadian General Electric, was formed, in 1896, General Electric was one of the original 12 companies listed on the newly formed Dow Jones Industrial Average. After 120 years, it is the one of the original companies still listed on the Dow index. In 1911, General Electric absorbed the National Electric Lamp Association into its lighting business, GE established its lighting division headquarters at Nela Park in East Cleveland, Ohio. Nela Park is still the headquarters for GEs lighting business, owen D. Young, through GE, founded the Radio Corporation of America in 1919 to further international radio. GE used RCA as its retail arm for radio sales from 1919, in 1927, Ernst Alexanderson of GE made the first demonstration of his television broadcasts at his General Electric Realty Plot home at 1132 Adams Rd, Schenectady, NY. The sound was broadcast on GEs WGY, experimental television station W2XAD evolved into station WRGB which—along with WGY and WGFM —was owned and operated by General Electric until 1983. GEs history of working with turbines in the field gave them the engineering know-how to move into the new field of aircraft turbosuperchargers. Led by Sanford Alexander Moss, GE introduced the first superchargers during World War I, superchargers became indispensable in the years immediately prior to World War II, and GE was the world leader in exhaust-driven supercharging when the war started. This experience, in turn, made GE a natural selection to develop the Whittle W.1 jet engine that was demonstrated in the United States in 1941, GE ranked ninth among United States corporations in the value of wartime production contracts. In 2002, GE acquired the assets of Enron during its bankruptcy proceedings. Some consumers boycotted GE light bulbs, refrigerators and other products in the 1980s and 1990s to protest GEs role in weapons production. With IBM, Burroughs, NCR, Control Data Corporation, Honeywell, RCA and UNIVAC, GE had a line of general purpose and special purpose computers
3.
Ultraviolet
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Ultraviolet is an electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays. UV radiation constitutes about 10% of the light output of the Sun. It is also produced by electric arcs and specialized lights, such as lamps, tanning lamps. Consequently, the effects of UV are greater than simple heating effects. Suntan, freckling and sunburn are familiar effects of over-exposure, along with risk of skin cancer. Living things on dry land would be damaged by ultraviolet radiation from the Sun if most of it were not filtered out by the Earths atmosphere. More-energetic, shorter-wavelength extreme UV below 121 nm ionizes air so strongly that it is absorbed before it reaches the ground, Ultraviolet is also responsible for the formation of bone-strengthening vitamin D in most land vertebrates, including humans. The UV spectrum thus has both beneficial and harmful to human health. Ultraviolet rays are invisible to most humans, the lens in a human eye ordinarily filters out UVB frequencies or higher, and humans lack color receptor adaptations for ultraviolet rays. Under some conditions, children and young adults can see ultraviolet down to wavelengths of about 310 nm, near-UV radiation is visible to some insects, mammals, and birds. Small birds have a fourth color receptor for ultraviolet rays, this gives birds true UV vision, reindeer use near-UV radiation to see polar bears, who are poorly visible in regular light because they blend in with the snow. UV also allows mammals to see urine trails, which is helpful for animals to find food in the wild. The males and females of some species look identical to the human eye. Ultraviolet means beyond violet, violet being the color of the highest frequencies of visible light, Ultraviolet has a higher frequency than violet light. He called them oxidizing rays to emphasize chemical reactivity and to them from heat rays. The terms chemical and heat rays were eventually dropped in favour of ultraviolet and infrared radiation, in 1878 the effect of short-wavelength light on sterilizing bacteria was discovered. By 1903 it was known the most effective wavelengths were around 250 nm, in 1960, the effect of ultraviolet radiation on DNA was established. The discovery of the ultraviolet radiation below 200 nm, named vacuum ultraviolet because it is absorbed by air, was made in 1893 by the German physicist Victor Schumann
4.
National Semiconductor
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National Semiconductor was an American semiconductor manufacturer which specialized in analog devices and subsystems, formerly with headquarters in Santa Clara, California, United States. The company produced power management integrated circuits, display drivers, audio and operational amplifiers, communication interface products, Nationals key markets included wireless handsets, displays and a variety of broad electronics markets, including medical, automotive, industrial and test and measurement applications. On September 23,2011, the company became part of Texas Instruments as the Silicon Valley division. The founding of the new company was followed by Sperry Rand filing a lawsuit against National Semiconductor for patent infringement, by 1965, as it was reaching the courts, the preliminaries of the lawsuit had caused the stock value of National to be depressed. The depressed stock values allowed Peter J Sprague to invest heavily in the company with Spragues family funds, Sprague also relied on further financial backing from a pair of west coast investment firms and a New York underwriter to take control as the Chairman of National Semiconductor. At that time Sprague was 27 years old, young characterised the era as the beginning of venture capitalism. That same year National Semiconductor acquired Molectro, Molectro was founded in 1962, in Santa Clara, California by J. Nall and D. Spittlehouse, who were formerly employed at Fairchild Camera and Instrument Corporation. The acquisition also brought to National Semiconductor two experts in linear semiconductor technologies, Robert Widlar and Dave Talbert, who were formerly employed at Fairchild. The acquisition of Molectro provided National with the technology to itself in the fabrication. In 1967, Sprague hired five top executives away from Fairchild, among whom were Charles E. Sporck, at the time of Sporcks hiring, Robert Noyce was de facto head of semiconductor operations at Fairchild and Sporck was his operations manager. Sporck was appointed President and CEO of National, to make the deal better for Sporcks hiring and appointment for half his former salary at Fairchild, Sporck was allotted a substantial share of Nationals stock. In essence, Sporck took four of his personnel from Fairchild with him as well as three others from TI, Perkin-Elmer and Hewlett Packard to form a new eight man team at National Semiconductor. Incidentally, Sporck had been Widlars superior at Fairchild before Widlar left Fairchild to join Molectro due to a dispute with Sporck. In 1968, National shifted its headquarters from Danbury, Connecticut to Santa Clara, however, like many companies, National retained its registration as a Delaware corporation, for legal and financial expediency. Over the years National Semiconductor acquired several companies like Fairchild Semiconductor, however, over time National Semiconductor spun off these acquisitions. Fairchild Semiconductor became a company again in 1997 and the Cyrix microprocessors division was sold to VIA Technologies of Taiwan in 1999. Based largely on the success of the WebPad National formed the Information Appliance division in 1998, the Information Appliance Division was sold to AMD in 2003. Immediately after becoming CEO, Sporck started a price war among semiconductor companies
5.
Programmable Array Logic
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Programmable Array Logic is a family of programmable logic device semiconductors used to implement logic functions in digital circuits introduced by Monolithic Memories, Inc. in March 1978. MMI obtained a trademark on the term PAL for use in Programmable Semiconductor Logic Circuits. The trademark is held by Lattice Semiconductor. PAL devices consisted of a small PROM core and additional output logic used to implement particular desired logic functions with few components, using specialized machines, PAL devices were field-programmable. PALs were available in variants, One-time programmable devices could not be updated and reused after initial programming. UV erasable versions had a window over the chip die. Later versions were flash erasable devices, in most applications, electrically-erasable GALs are now deployed as pin-compatible direct replacements for one-time programmable PALs. One PAL device would typically replace dozens of discrete logic packages. PALs were used advantageously in many products, such as minicomputers, PALs were not the first commercial programmable logic devices, Signetics had been selling its field programmable logic array since 1975. These devices were completely unfamiliar to most circuit designers and were perceived to be too difficult to use, the FPLA had a relatively slow maximum operating speed, was expensive, and had a poor reputation for testability. Another factor limiting the acceptance of the FPLA was the large package, the project to create the PAL device was managed by John Birkner and the actual PAL circuit was designed by H. T. Chua. In a previous job, Birkner had developed a 16-bit processor using 80 standard logic devices and his experience with standard logic led him to believe that user programmable devices would be more attractive to users if the devices were designed to replace standard logic. This meant that the package sizes had to be typical of the existing devices. MMI intended PALs to be a low cost part. However, they initially had severe manufacturing yield problems and had to sell the devices for over $50 and this threatened the viability of the PAL as a commercial product and they were forced to license the product line to National Semiconductor. PALs were later second sourced by Texas Instruments and Advanced Micro Devices, early PALs were 20-pin DIP components fabricated in silicon using bipolar transistor technology with one-time programmable titanium-tungsten programming fuses. Later devices were manufactured by Cypress, Lattice Semiconductor and Advanced Micro Devices using CMOS technology, the original 20 and 24-pin PALs were denoted by MMI as medium-scale integration devices. The PAL architecture consists of two components, a logic plane and output logic macrocells
6.
Integrated circuit
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An integrated circuit or monolithic integrated circuit is a set of electronic circuits on one small flat piece of semiconductor material, normally silicon. The ICs mass production capability, reliability and building-block approach to circuit design ensured the rapid adoption of standardized ICs in place of using discrete transistors. ICs are now used in all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, and other home appliances are now inextricable parts of the structure of modern societies, made possible by the small size. These advances, roughly following Moores law, allow a computer chip of 2016 to have millions of times the capacity, ICs have two main advantages over discrete circuits, cost and performance. Cost is low because the chips, with all their components, are printed as a unit by photolithography rather than being constructed one transistor at a time, furthermore, packaged ICs use much less material than discrete circuits. Performance is high because the ICs components switch quickly and consume little power because of their small size, the main disadvantage of ICs is the high cost to design them and fabricate the required photomasks. This high initial cost means ICs are only practical when high production volumes are anticipated, Circuits meeting this definition can be constructed using many different technologies, including thin-film transistor, thick film technology, or hybrid integrated circuit. However, in general usage integrated circuit has come to refer to the single-piece circuit construction originally known as a integrated circuit. Jacobi disclosed small and cheap hearing aids as typical industrial applications of his patent, an immediate commercial use of his patent has not been reported. The idea of the circuit was conceived by Geoffrey Dummer. Dummer presented the idea to the public at the Symposium on Progress in Quality Electronic Components in Washington and he gave many symposia publicly to propagate his ideas, and unsuccessfully attempted to build such a circuit in 1956. A precursor idea to the IC was to create small ceramic squares, Components could then be integrated and wired into a bidimensional or tridimensional compact grid. This idea, which seemed very promising in 1957, was proposed to the US Army by Jack Kilby, however, as the project was gaining momentum, Kilby came up with a new, revolutionary design, the IC. In his patent application of 6 February 1959, Kilby described his new device as a body of semiconductor material … wherein all the components of the circuit are completely integrated. The first customer for the new invention was the US Air Force, Kilby won the 2000 Nobel Prize in Physics for his part in the invention of the integrated circuit. His work was named an IEEE Milestone in 2009, half a year after Kilby, Robert Noyce at Fairchild Semiconductor developed his own idea of an integrated circuit that solved many practical problems Kilbys had not. Noyces design was made of silicon, whereas Kilbys chip was made of germanium, Noyce credited Kurt Lehovec of Sprague Electric for the principle of p–n junction isolation, a key concept behind the IC
7.
EPROM
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An EPROM, or erasable programmable read-only memory, is a type of memory chip that retains its data when its power supply is switched off. Computer memory that can retrieve stored data after a power supply has been turned off and it is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages than those normally used in digital circuits. Once programmed, an EPROM can be erased by exposing it to ultraviolet light source. Development of the EPROM memory cell started with investigation of faulty integrated circuits where the connections of transistors had broken. Stored charge on these isolated gates changed their properties, the EPROM was invented by Dov Frohman of Intel in 1971, who was awarded US patent 3660819 in 1972. Each storage location of an EPROM consists of a single field-effect transistor, each field-effect transistor consists of a channel in the semiconductor body of the device. Source and drain contacts are made to regions at the end of the channel, an insulating layer of oxide is grown over the channel, then a conductive gate electrode is deposited, and a further thick layer of oxide is deposited over the gate electrode. The floating gate electrode has no connections to parts of the integrated circuit and is completely insulated by the surrounding layers of oxide. A control gate electrode is deposited and further oxide covers it, to retrieve data from the EPROM, the address represented by the values at the address pins of the EPROM is decoded and used to connect one word of storage to the output buffer amplifiers. Each bit of the word is a 1 or 0, depending on the transistor being switched on or off. The switching state of the transistor is controlled by the voltage on the control gate of the transistor. Presence of a voltage on this gate creates a channel in the transistor. In effect, the charge on the floating gate allows the threshold voltage of the transistor to be programmed. Storing data in the memory requires selecting a given address and applying a voltage to the transistors. This creates an avalanche discharge of electrons, which have enough energy to pass through the oxide layer. When the high voltage is removed, the electrons are trapped on the electrode, because of the high insulation value of the silicon oxide surrounding the gate, the stored charge cannot readily leak away and the data can be retained for decades. The programming process is not electrically reversible, to erase the data stored in the array of transistors, ultraviolet light is directed onto the die. Photons of the UV light cause ionization within the silicon oxide, since the whole memory array is exposed, all the memory is erased at the same time
8.
Digital electronics
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Digital electronics or digital circuits are electronics that handle digital signals rather than by continuous ranges as used in analog electronics. All levels within a band of values represent the information state. In most cases, the number of states is two, and they are represented by two voltage bands, one near a reference value, and the other a value near the supply voltage. These correspond to the false and true values of the Boolean domain respectively, Digital techniques are useful because it is easier to get an electronic device to switch into one of a number of known states than to accurately reproduce a continuous range of values. Digital electronic circuits are made from large assemblies of logic gates. The binary number system was refined by Gottfried Wilhelm Leibniz and he established that by using the binary system. Digital logic as we know it was the brain-child of George Boole, Boole died young, but his ideas lived on. In an 1886 letter, Charles Sanders Peirce described how logical operations could be carried out by electrical switching circuits, eventually, vacuum tubes replaced relays for logic operations. Lee De Forests modification, in 1907, of the Fleming valve can be used as an AND logic gate, ludwig Wittgenstein introduced a version of the 16-row truth table as proposition 5.101 of Tractatus Logico-Philosophicus. Walther Bothe, inventor of the circuit, got part of the 1954 Nobel Prize in physics. Mechanical analog computers started appearing in the first century and were used in the medieval era for astronomical calculations. In World War II, mechanical computers were used for specialized military applications such as calculating torpedo aiming. During this time the first electronic computers were developed. Originally they were the size of a room, consuming as much power as several hundred modern personal computers. The Z3 was a computer designed by Konrad Zuse, finished in 1941. It was the worlds first working programmable, fully automatic digital computer and its operation was facilitated by the invention of the vacuum tube in 1904 by John Ambrose Fleming. Purely electronic circuit elements soon replaced their mechanical and electromechanical equivalents, the bipolar junction transistor was invented in 1947. From 1955 onwards transistors replaced vacuum tubes in computer designs, giving rise to the generation of computers
9.
Texas Instruments
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Texas Instruments Inc. is an American technology company that designs and manufactures semiconductors, which it sells to electronics designers and manufacturers globally. Headquartered in Dallas, Texas, United States, TI is one of the top ten semiconductor companies worldwide, Texas Instrumentss focus is on developing analog chips and embedded processors, which accounts for more than 85% of their revenue. TI also produces TI digital light processing technology and education technology products including calculators, microcontrollers, to date, TI has more than 43,000 patents worldwide. TI produced the worlds first commercial silicon transistor in 1950, Jack Kilby invented the integrated circuit in 1958 while working at TIs Central Research Labs. TI also invented the hand-held calculator in 1967, and introduced the first single-chip microcontroller in 1970, in 1987, TI invented the digital light processing device, which serves as the foundation for the companys award-winning DLP technology and DLP Cinema. In 1990, TI came out with the popular TI-81 calculator which made them a leader in the calculator industry. In 1997, its business was sold to Raytheon, which allowed TI to strengthen its focus on digital solutions. Texas Instruments was founded by Cecil H. Green, J. Erik Jonsson, Eugene McDermott, McDermott was one of the original founders of Geophysical Service Inc. in 1930. McDermott, Green, and Jonsson were GSI employees who purchased the company in 1941, in November,1945, Patrick Haggerty was hired as general manager of the Laboratory and Manufacturing division, which focused on electronic equipment. By 1951, the L&M division, with its contracts, was growing faster than GSIs Geophysical division. The company was reorganized and initially renamed General Instruments Inc, because there already existed a firm named General Instrument, the company was renamed Texas Instruments that same year. From 1956 to 1961, Fred Agnich of Dallas, later a Republican member of the Texas House of Representatives, was the Texas Instruments president, Geophysical Service, Inc. became a subsidiary of Texas Instruments. Early in 1988 most of GSI was sold to the Halliburton Company, in 1930, J. Clarence Karcher and Eugene McDermott founded Geophysical Service, an early provider of seismic exploration services to the petroleum industry. In 1939, the company reorganized as Coronado Corp. an oil company with Geophysical Service Inc, on December 6,1941, McDermott along with three other GSI employees, J. Erik Jonsson, Cecil H. Green, and H. B. During World War II, GSI expanded their services to include electronics for the U. S. Army, Signal Corps, in 1951, the company changed its name to Texas Instruments, GSI becoming a wholly owned subsidiary of the new company. Texas Instruments also continued to manufacture equipment for use in the seismic industry, after selling GSI, TI finally sold the company to Halliburton in 1988, at which point GSI ceased to exist as a separate entity. Texas Instruments entered the electronics market in 1942 with submarine detection equipment. During the early 1980s, Texas Instruments instituted a quality program which included Juran training, as well as promoting statistical process control, Taguchi methods and Design for Six Sigma
10.
In-system programming
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There are several mutually-incompatible in-system programming protocols for programming microcontroller devices, including PIC microcontrollers, AVRs, and the Parallax Propeller. ICSP has been implemented by Microchip Technology for programming PIC and dsPIC devices. Microcontrollers are typically soldered directly to a circuit board and usually do not have the circuitry or space for a large external programming cable to another computer. Most programmable logic devices use a variant of the JTAG protocol for ISP, other devices usually use proprietary protocols or protocols defined by older standards. An example of devices using ISP is the AVR line of micro-controllers by Atmel such as the ATmega series, for most Microchip microcontrollers, ICSP programming is performed using two pins, clock and data, while a high voltage is present on the Vpp/MCLR pin. Low voltage programming dispenses with the voltage, but reserves exclusive use of an I/O pin. However, for newer microcontrollers, specifically PIC18F6XJXX/8XJXX microcontrollers families, entering into ICSP modes is a bit different, entering ICSP Program/Verify mode requires the following three steps, Voltage is briefly applied to the MCLR pin. A 32-bit key sequence is presented on PGD, a separate piece of hardware, called a programmer is required to connect to an I/O port of a PC on one side and to the PIC on the other side. Most laptops newer than 2010 do not support this port, parallel port programming is very fast. Serial port - At one time the most popular method, serial ports usually lack adequate circuit programming supply voltage. Most computers and laptops newer than 2010 lack support for this port, socket - the CPU must be either removed from circuit board, or a clamp must be attached to the chip making access an issue. USB cable - Small and light weight, has support for voltage source, the distance between the circuit to be programmed and the computer is limited by the length of USB cable - it must usually be less than 180 cm. This can make programming devices deep in machinery or cabinets a problem, ICSP programmers have many advantages, with size, computer port availability, and power source being major features. Due to variations in the scheme and the target circuit surrounding a micro-controller. Microchip provides a detailed ICSP programming guide Many sites provide programming, PICs are programmed using five signals. The data is transferred using a two wire synchronous serial scheme, three more wires provide programming and chip power, the clock signal is always controlled by the programmer. This must be connected to the MCLR pin, or the Vpp pin of the optional ICSP port available on some large-pincount PICs, to put the PIC into programming mode, this line must be in a specified range that varies from PIC to PIC. For 5 V PICs, this is some amount above Vdd
11.
Field-programmable gate array
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A field-programmable gate array is an integrated circuit designed to be configured by a customer or a designer after manufacturing – hence field-programmable. The FPGA configuration is generally specified using a description language. Logic blocks can be configured to perform complex functions, or merely simple logic gates like AND. In most FPGAs, logic blocks also include elements, which may be simple flip-flops or more complete blocks of memory. Contemporary field-programmable gate arrays have large resources of logic gates and RAM blocks to implement complex digital computations, as FPGA designs employ very fast I/Os and bidirectional data buses, it becomes a challenge to verify correct timing of valid data within setup time and hold time. Floor planning enables resources allocation within FPGAs to meet time constraints. FPGAs can be used to implement any logical function that an ASIC could perform, some FPGAs have analog features in addition to digital functions. Fairly common are differential comparators on input pins designed to be connected to differential signaling channels, the FPGA industry sprouted from programmable read-only memory and programmable logic devices. PROMs and PLDs both had the option of being programmed in batches in a factory or in the field, however, programmable logic was hard-wired between logic gates. In the late 1980s, the Naval Surface Warfare Center funded an experiment proposed by Steve Casselman to develop a computer that would implement 600,000 reprogrammable gates, Casselman was successful and a patent related to the system was issued in 1992. Some of the foundational concepts and technologies for programmable logic arrays, gates. Xilinx co-founders Ross Freeman and Bernard Vonderschmitt invented the first commercially viable field-programmable gate array in 1985 – the XC2064, the XC2064 had programmable gates and programmable interconnects between gates, the beginnings of a new technology and market. The XC2064 had 64 configurable logic blocks, with two three-input lookup tables, more than 20 years later, Freeman was entered into the National Inventors Hall of Fame for his invention. Altera and Xilinx continued unchallenged and quickly grew from 1985 to the mid-1990s, by 1993, Actel was serving about 18 percent of the market. By 2010, Altera, Actel and Xilinx together represented approximately 77 percent of the FPGA market, the 1990s were an explosive period of time for FPGAs, both in sophistication and the volume of production. In the early 1990s, FPGAs were primarily used in telecommunications, by the end of the decade, FPGAs found their way into consumer, automotive, and industrial applications. This work mirrors the architecture by Ron Perlof and Hana Potash of Burroughs Advanced Systems Group which combined a reconfigurable CPU architecture on a chip called the SB24. That work was done in 1982, the Atmel FPSLIC is another such device, which uses an AVR processor in combination with Atmels programmable logic architecture
12.
Static random-access memory
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Static random-access memory is a type of semiconductor memory that uses bistable latching circuitry to store each bit. SRAM exhibits data remanence, but it is volatile in the conventional sense that data is eventually lost when the memory is not powered. The term static differentiates SRAM from DRAM which must be periodically refreshed, SRAM is faster and more expensive than DRAM, it is typically used for CPU cache while DRAM is used for a computers main memory. Several techniques have been proposed to power consumption of SRAM-based memory structures. Some amount is also embedded in all modern appliances, toys. Several megabytes may be used in products such as digital cameras, cell phones, synthesizers. SRAM in its form is sometimes used for realtime digital signal processing circuits. LCD screens and printers also normally employ static RAM to hold the image displayed, static RAM was used for the main memory of some early personal computers such as the ZX80, TRS-80 Model 100 and Commodore VIC-20. Hobbyists, specifically homebuilt processor enthusiasts, often prefer SRAM due to the ease of interfacing and it is much easier to work with than DRAM as there are no refresh cycles and the address and data buses are directly accessible rather than multiplexed. In addition to buses and power connections, SRAM usually requires only three controls, Chip Enable, Write Enable and Output Enable, in synchronous SRAM, Clock is also included. Non-volatile SRAMs, or nvSRAMs, have standard SRAM functionality, but they save the data when the supply is lost. NvSRAMs are used in a range of situations – networking, aerospace, and medical, among many others – where the preservation of data is critical. Address, data in and other signals are associated with the clock signals In 1990s. Nowadays, synchronous SRAM is rather employed similarly like Synchronous DRAM – DDR SDRAM memory is used than asynchronous DRAM. Synchronous memory interface is much faster as access time can be reduced by employing pipeline architecture. Furthermore, as DRAM is much cheaper than SRAM, SRAM is often replaced by DRAM, SRAM memory is however much faster for random access. Therefore, SRAM memory is used for CPU cache, small on-chip memory. Zero bus turnaround – the turnaround is the number of cycles it takes to change access to the SRAM from write to read
