АкушерствоАнатомияАнестезиологияВакцинопрофилактикаВалеологияВетеринарияГигиенаЗаболеванияИммунологияКардиологияНеврологияНефрологияОнкологияОториноларингологияОфтальмологияПаразитологияПедиатрияПервая помощьПсихиатрияПульмонологияРеанимацияРевматологияСтоматологияТерапияТоксикологияТравматологияУрологияФармакологияФармацевтикаФизиотерапияФтизиатрияХирургияЭндокринологияЭпидемиология

Extract B

Прочитайте:
  1. Extract A
  2. Extract A
  3. Extract B

When building a circuit, it is very important that all connections are intact. If not, the electrical current will be stopped on its way through the circuit, making the circuit fail. Before the integrated circuit, assembly workers had to construct circuits by hand, soldering each component in place and connecting them with metal wires. Engineers soon realized that manually assembling the vast number of tiny components needed in, for example, a computer would be impossible, especially without generating a single faulty connection. Another problem was the size of the circuits. A complex circuit, like a computer, was dependent on speed. If the components of the computer were too large or the wires interconnecting them too long, the electric signals couldn't travel fast enough through the circuit, thus making the computer too slow to be effective. So there was a problem of numbers. Advanced circuits contained so many components and connections that they were virtually impossible to build. This problem was known as the tyranny of numbers. The integrated circuit has come a long way since Jack Kilby's first prototype. His idea founded a new industry and is the key element behind our computerized society. Today the most advanced circuits contain several hundred millions of components on an area no larger than a fingernail. The transistors on these chips are around 90 nm, that is 0.00009 millimeters*, which means that you could fit hundreds of these transistors inside a red blood cell. Each year computer chips become more powerful yet cheaper than the year before. Gordon Moore, one of the early integrated circuit pioneers and founders of Intel once said, "If the auto industry advanced as rapidly as the semiconductor industry, a Rolls Royce would get a half a million miles per gallon, and it would be cheaper to throw it away than to park it."**

 

*1 inch = 25.4 millimeters

**1 US gallon = 3.8 litres, 1 mile = 1.6 km

 


Дата добавления: 2015-09-27 | Просмотры: 635 | Нарушение авторских прав







При использовании материала ссылка на сайт medlec.org обязательна! (0.004 сек.)