外文原文：
VLSI Technology
One of the key inventions in the history of electronics，and in fact one of the most important inventions ever period，was the transistor．It was invented by Bell Laboratories in 1948．In short，a transistor is a device that conducts a variable amount of electricity through it，depending on how much electricity is input to it．In other words，it is a digital switch．However，unlike the vacuum tube，it is solid state．This means that it doesn’t change its physical form as it switches．There are no moving parts in a transistor．
英文童话故事The advantages of the transistor over the vacuum tube were enormous．Compared to the old technology，transistors were much smaller， faster， and cheaper to manufacture．They were also far more reliable and ud much 1ess power．The transistor is what started the evolution of the modern computer industry in motion．
The transistor was originally a single，discrete device，which you could p1ace individually
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into a circuit much like any other．Today，some special-purpo transistors are still ud that way．What allowed the creation of modern processors was the invention of the integrated circuit，which is a group of transistors manufactured from a single piece of material and connected together internally，without extra wiring．Integrated circuits are also called ICs or chips．
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A special material is ud to make the integrated circuits．While most materials either insulate from electrical flow (air，glass，wood) or conduct electricity readily(metals,water)，there are some that only conduct electricity a small amount。or only under certain conditions．The are called miconductors．The most commonly ud miconductor is of cour silicon．
By careful chemical composition and arrangement，it is possible to create a very small transistor directly on a layer of silicon，using various technologies to manipulate the material into the correct form．The transistors are small，fast and reliable,and u relatively little power．The first integrated circuit was invented in 1959 bv Texas Instruments.It contained just six transistors on a single miconductor surface.
After the invention of the integrated circuit，it took very little time to realize the tremendous benefits of miniaturizing and integrating larger numbers of transistors into the same integrated circuit.More transistors(switches) were required in order to implement more complicated functions.Miniaturization was the key to integrating together large numbers of transistors while increasing hardware speed and keeping power consumption and space requirements manageable.
Large语音翻译机-dress的复数scale integration(“LSI”)came to refer to the creation of integrated cirhow do you ecuitsfiypaper卖服装的语言技巧 that had previously been made from multiple discrete components.The devices typically contained hundreds of transistors.Early computers were made from many of 英文求职信the smaller ICs connected together on circuit boards.
As time progresd after the invention of LSI integrated circuits，the technology improved and chips became smaller，faster and cheaper.Building on the success of earlier integration efforts，engineers learned to pack more and more logic into a single circuit.This effort became known as very large scale integration(VLSI).VLSI circuits can contain millions of transistors.
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Originally，the functions performed by a processor were implemented using veral different logic chips．Intel was the first company to incorporate a11 of the logic components into a single chip.This was the first microprocessor，the 4004，introduced by Intel in 1971.All of today’s processors are(highly advanced!)descendants of this original 4-bit CPU.
Memory Devices
Memories can be made in mechanical，magnetic，optical，biological and electronic technologies.Examples of magnetic memories are tapes，floppy disks，hard drives and ferroelectric RAMs.Examples of optical memories are CD—ROMs，rewrittable CDs.Electronic memory is ud extensively in computer equipment since it is the fastest available.For applications where speed is less important，magnetic and optical techno1ogies are often ud.
The flip-flop A filp-flop is basically a bi-state circuit in which eight a 0 or 1 state can resides.Becau of its simplicity，the flip-flop is extremely fast.As a basic element，the fl
ip-flop is ud in digital circuits and ICs.A flip-flop will lo its state when the supply voltage is removed.Therefore，it is volatile.
The register A register is a t of flip-flops in parallel．Typically a register is 8，16，32 or 64 bits wide.Often a register is ud to hold data，address pointers，etc．A register is volatile and very fast just like the flip—flop.
