TABLE OF CONTENTS The previous chapter emphasized how the opamp frequency response interacts with a simple feedback circuit to provide various effects. This chapter continues out-effort to develop better understanding of opamp behavior. The emphasis is on circuit design and what is involved to actually achieve 100 dB of open-loop gain. In addition, some issues involved with controlling the bandwidth and cut off rates for the gain response are also considered. Both the voltage controlled voltage source (VCVS) and current controlled current source (CCCS) structures are studied, and it is interesting to see that there is not much difference between the two structures.
The goal of the chapter is to study a typical, or generic, opamp structure to enable the student to develop a feel for opamp design issues and see problems related to operating point stability and frequency response for high-gain circuits. As will be seen, such circuits are not trivial, and the performance limitations they offer are easier to understand when some design structures are known.
The material in this chapter is not critical to the development of concepts in this text related to active filter synthesis procedures. Consequently, if is possible to skip this entire chapter. It has been included for the curious student who wishes to know more about opamp design, terminology, and performance ideas. Whether or not this material were included in any course would depend upon available time and course objectives.
The opamp design story begins with a consideration of current mirrors.
