Asee peer logo

Simple Way Of Teaching Transistor Amplifiers

Download Paper |


2000 Annual Conference


St. Louis, Missouri

Publication Date

June 18, 2000

Start Date

June 18, 2000

End Date

June 21, 2000



Page Count


Page Numbers

5.547.1 - 5.547.9

Permanent URL

Download Count


Request a correction

Paper Authors

author page

Bogdan M. Wilamowski

Download Paper |

NOTE: The first page of text has been automatically extracted and included below in lieu of an abstract

Session 2793

Simple way of teaching transistor amplifiers Bogdan M. Wilamowski University of Wyoming


For small signal analysis a simple change from commonly used tranconductance gm to transresistance rm=1/gm leads to a significant simplification of all equations. Moreover these equations are much easier to memorize since they have a form of resistor ratio for CE (CS) and CB (CG) configurations and the form or resistor divider for CC (CD) configuration. With presented approach most of students are able to read diagrams and to understand the effect of each element change on the circuit performance. Students are not lost with messy equations, but they are in control of their design and they know which parameters they have to change in order to change behavioral characteristics.

I. Introduction

Students usually have significant difficulties in memorizing all the equations for calculation of gain, input and output resistances for transistor amplifiers [1][2][3][4]. They do relatively well if a common source (emitter) is used, but they are lost when other configurations are considered. In the paper, a simple way for analysis of transistor amplifiers is introduced. At first, approximate and accurate methods for circuit biasing are discussed including both BJT and FET amplifiers. All transistor circuit analysis should be always performed in the following order: 1. Biasing point calculation 2. Calculation of small signal parameters 3. Gain, input and output resistance calculation This paper is also organized in that way. iD D

G + + VGS - S VGX RS - X

Fig. 1 Biasing calculation for FET transistor with series of resistor RS

II. Biasing calculation

Calculation of the biasing point for bipolar transistor circuits are relatively straightforward and usually students do not have a problem with that. If it would be possible one should

Wilamowski, B. M. (2000, June), Simple Way Of Teaching Transistor Amplifiers Paper presented at 2000 Annual Conference, St. Louis, Missouri.

ASEE holds the copyright on this document. It may be read by the public free of charge. Authors may archive their work on personal websites or in institutional repositories with the following citation: © 2000 American Society for Engineering Education. Other scholars may excerpt or quote from these materials with the same citation. When excerpting or quoting from Conference Proceedings, authors should, in addition to noting the ASEE copyright, list all the original authors and their institutions and name the host city of the conference. - Last updated April 1, 2015