Dour It will appear in a range of applications,extending from the simple to the very complex. In metric units,the resistivity of a material is measured in -cm or -m. The term conductor is applied to any material that will support a generous flow of charge when a voltage source analogiva limited magnitude is applied across its terminals. Inversely related to the conductivity of a material is its resistance to the flow of charge,or current. We have also reached a point at which the primary purpose of the container is simply to provide some means of handling the device or system and to provide a mechanism for attachment to the remainder of the network.
|Published (Last):||23 November 2019|
|PDF File Size:||3.91 Mb|
|ePub File Size:||10.22 Mb|
|Price:||Free* [*Free Regsitration Required]|
Dat The characteristics of an ideal diode are those of a switch that can conduct current in only one direction. In addition to the details of its construction and characteristics,the very important data and graphs to be found on specification sheets will also be covered to ensure an understanding of the terminology employed and to demonstrate the wealth of information typically available from manufacturers. A semiconductor, therefore, is a material that has a conductivity level somewhere between the extremes of an insulator and a conductor.
It will appear in a range of applications,extending from the simple to the very complex. In general,it is relatively simple to determine whether a diode is in the region of conduction or nonconduction simply by noting the direction of the current IDestablished by an applied voltage. One of the important parameters for the diode is the resistance at the point or re- gion of operation. The label semiconductoritself provides a hint as to its characteristics.
Consider the region of negatively applied potential third quadrant of Fig. It no longer seems valid to mention tubes at all or to compare the advantages of one over the other—we are firmly in the solid-state era. It is now some 50 years since the first transistor eletronlca introduced on December 23, Ideally,a diode will conduct current in the direction defined by the arrow in the symbol and act like an open circuit to any attempt to establish current in the opposite direction.
That is,the higher the conductivity level,the lower the resistance level. As we progress through the next few sections,keep the following questions in mind:. If the current through the diode has the direction indicated in Fig. In the description of the elements to follow,it is critical that the various letter symbols,voltage polarities,and current directionsbe defined.
In fact,if the area of Fig. Anallgica systems now appear on wafers thousands of times smaller than the single element of earlier networks. In tables,the term resistivity ,Greek letter rho is often used when comparing the resistance levels of materials.
The ideal diode, therefore, is an open circuit in the region of nonconduction. The comments from these individuals have enabled us to present Electronic Devices and Circuit Theory in this Seventh Edition:. Our sincerest appreciation must be extended to the instructors who have used the text and sent in comments, corrections, and suggestions. Inversely related to the conductivity of a material is its resistance to the flow of charge,or current.
As you will find in the chapters to follow,they are certainly not the only two semiconductor materials. For conventional flow opposite to that of electron flowif the resultant diode current has the same direction as the arrowhead of the diode symbol,the diode is operating in the conducting region as depicted in Fig. The term conductor is applied to any material that will support a generous flow eletronia charge when a voltage source of limited magnitude is applied across its terminals.
New designs and systems surface weekly. The first electronic device to be introduced is called the diode. We also want to thank Rex Davidson, Production Editor at Prentice Hall, for keeping together the many detailed aspects of production. The engineer becomes more and more limited in his or her knowledge of the broad range of advances— it is difficult enough simply to stay abreast of the changes in one area of research eletonica development.
We wish to thank those individuals who have shared their suggestions and evaluations of this text eletronifa its many editions. The miniaturization that has resulted leaves us to wonder about its limits. It provides a basis for comparison,and it reveals where improvements can still be made. It is the simplest of semiconductor devices but plays a very vital role in electronic systems,having characteristics that closely match those of a simple switch. Conductor Semiconductor Insulator mica from your past studies,the characteristics of the semiconductor materials of germanium Ge and silicon Si may be relatively new.
Parte 1 de 6. They are,however,the two materials that have received the broadest range of interest in the development of semiconductor devices. Eletronica analogica Apostila sobre eletronica analogica 1. As indicated earlier,the primary purpose of this section is to introduce the characteristics of an ideal device for comparison with the characteristics of the commercial variety.
Although you may be familiar with the electrical properties of copper and. Most 10 Related.
Categoria: Circuitos & Projetos
Apol 05 Eletronica Analogica