A Simplistic Approach to the Analysis of Transistor Amplifiers

The traditional approach to the small-signal analysis of transistor amplifiers employs the transistor models with dependent sources, illustrated in Figure 18.1, for both the MOS and BJT devices. In this chapter, techniques for the analysis of transistor circuits will be demonstrated without the use of a small-signal equivalent circuit containing dependent sources. Because of the similarities inherent in the two circuit configurations shown in Figure 18.1, the following analyses will address both MOS and BJT devices in unison. As a general rule, the small signal parameters are calculated as a function of the transistor currents. In view of that fact, consider now each type of device.