1 / 6

The Physics of the Transistor

The Physics of the Transistor. Jim Royston Electronic Engineering La Trobe University. The B-E junction is forward biased and the C-B junction is reverse biased.

ilori
Télécharger la présentation

The Physics of the Transistor

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Physics of the Transistor Jim Royston Electronic Engineering La Trobe University

  2. The B-E junction is forward biased and the C-B junction is reverse biased. • There is an exponential relationship between the thickness of the B-E depletion region and the current of electrons "injected" into the base as minority carriers.

  3. The base region is very thin and has a lower doping than the emitter or collector. • The profile of concentration of minority carriers (electrons in an NPN transistor) in the base is linear. • The amplifying action is produced by transferring a current from a low-resistance circuit to a high resistance circuit. • transfer + resistor→ transistor

  4. The C-B junction has a reverse bias leakage current ICBO which is typically microamps or nanoamps, and can be neglected unless temperature effects are important. • Approximately, ICEO ≈ βICBO but both currents are small. • There is an injection of holes into the emitter, where they are minority carriers, from the base – this can be kept small by heavily doping the emitter with donor impurities.

  5. Gray, P. R. & Meyer, R. G., "Analysis & Design of Analog Integrated Circuits", 3rd edition 1993, New York, John Wiley & Sons.

  6. References • William Beaty "How Do Transistors Work?" 1995 http://amasci.com/amateur/transis.html • Wikipedia "Bipolar Junction Transistors" accessed 2007 http://en.wikipedia.org/wiki/Bjt • Gray, P. R. & Meyer, R. G., "Analysis & Design of Analog Integrated Circuits", 3rd edition 1993, New York, John Wiley & Sons. • Bogart, T. F. et al, "Electronic Devices & Circuits", 3rd edition 2001, Upper Saddle River, New Jersey, Prentice-Hall (Pearson). • Boylestad, R. L. & Nashelsky, L., "Electronic Devices and Circuit Theory", 8th edition 2003, Upper Saddle River, New Jersey, Prentice-Hall (Pearson).

More Related