Quantcast SEMICONDUCTOR THEORY

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
1-5 with over a thousand volts applied to its plate whereas the maximum allowable voltage for a transistor is limited to about 200 volts (usually 50 volts or less). A tube can also handle thousands of watts of power. The maximum power output for transistor generally ranges from 30 milliwatts to slightly over 100 watts. When it comes to ruggedness and life expectancy, the tube is still in competition. Design and functional requirements usually dictate the choice of device. However, semiconductor devices are rugged and long-lived. They can be constructed to withstand extreme vibration and mechanical shock. They have been known to withstand impacts that would completely shatter an ordinary electron tube. Although some specially designed tubes render extensive service, the life expectancy of transistors is better than three to four times that of ordinary electronic tubes. There is no known failure mechanism (such as an open filament in a tube) to limit the semiconductor’s life. However, semiconductor devices do have some limitations. They are usually affected more by temperature, humidity, and radiation than tubes are. Q3.   Name three of the largest users of semiconductor devices. Q4.   State one requirement of an electron tube, which does not exist for semiconductors, that makes the tube less efficient than the semiconductor. SEMICONDUCTOR THEORY To understand why solid-state devices function as they do, we will have to examine closely the composition and nature of semiconductors. This entails theory that is fundamental to the study of solid- state devices. Rather than beginning with theory, let’s first become reacquainted with some of the basic information you studied earlier concerning matter and energy (NEETS, Module 1). ATOMIC STRUCTURE The universe, as we know it today, is divided into two parts: matter and energy. Matter, which is our main concern at this time, is anything that occupies space and has weight. Rocks, water, air, automobiles, clothing, and even our own bodies are good examples of matter. From this, we can conclude that matter may be found in any one of three states: SOLIDS, LIQUIDS, and GASES. All matter is composed of either an element or combination of elements. As you know, an element is a substance that cannot be reduced to a simpler form by chemical means. Examples of elements with which you are in contact everyday are iron, gold, silver, copper, and oxygen. At present, there are over 100 known elements of which all matter is composed. As we work our way down the size scale, we come to the atom, the smallest particle into which an element can be broken down and still retain all its original properties. The atoms of one element, however, differ from the atoms of all other elements. Since there are over 100 known elements, there must be over 100 different atoms, or a different atom for each element. Now let us consider more than one element at a time. This brings us to the term "compound." A compound is a chemical combination of two or more elements. Water, table salt, ethyl alcohol, and ammonia are all examples of compounds. The smallest part of a compound, which has all the characteristics of the compound, is the molecule. Each molecule contains some of the atoms of each of the elements forming the compound. Consider sugar, for example. Sugar in general terms is matter, since it occupies space and has weight. It is also a compound because it consists of two or more elements. Take a lump of sugar and crush


Electrical News
EEVblog #737 – World’s Biggest Collection Of Electronics Components
Dave uncovers that has to be one of the world’s...
eevblog.com
ARM Gives Peek at Road Map
ARM disclosed new details of its A72, including three functional...
eetimes.com
Cypress Expands Error Correcting Code For SRAM
As overall SRAM market shrinks, Cypress sees uptick in automotive,...
eetimes.com
EUV Deal Raises Questions
ASML announced it struck a deal to sell 15 EUV...
eetimes.com
Make Field-oriented Motor Control Affordable
Shaft sensors and their wiring make field-oriented motor control pricey,...
eetimes.com
Why Connect Cars?
EE Times will host a radio show on "Why Connect...
eetimes.com
Time Flies Like an Arrow & Fruit Flies Like Bananas
Using a computer to translate something like a technical article...
eetimes.com
NXP-Freescale Mega Merger on Track
Five companies, aside from NXP, were in talks with Freescale,...
eetimes.com
Basic University Research Key to Industry Progress
A basic, precompetitive research base is required to continue to...
eetimes.com
MEMS Seeks its Moore's Law
MEMS provide an alternative route to scaling technology beyond Moore's...
eetimes.com
Wireless Charging Gets Universal Antenna
NuCurrent believe the company's 50 patents in areas such as...
eetimes.com
Friday Quiz: EMI and EMC
EDN's Designer's Guide to Electromagnetic Compatibility, written by Bill Kimmel...
eetimes.com
EEVBlog #736 – World’s First IR Thermal Camera Watch
A quick hack turns a Flir TG165 Thermal camera into...
eevblog.com
Wave of 100th Birthday Celebrations Rolls Around the World
Following the party Max's family held to celebrate what would...
eetimes.com
Qualcomm Seeking Options Beyond Apple, Samsung
Qualcomm's recent earnings reports suggest significant vulnerabilities. Qualcomm is heavily...
eetimes.com
Elvis Sees All in Russia
A Russian company claims it has the first Russian designed...
eetimes.com
Smartwatch Uptick in Mobile Slump
Smartwatches could grow to sales of 400 million units a...
eetimes.com
8 Views of Security from RSA
Security was in focus at RSA Conference with top cryptographers,...
eetimes.com
Electricity, Energy and Global Warming By the Numbers, Part 2
Numerous factors contribute to climate change. In Part 2, we...
eetimes.com
10 Trailblazing Companies For Women In IT
On the following pages, we'll take you beyond the tech...
eetimes.com
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +