EE-252. Electronics 2
Credits: 4
Analysis and design of analog integrated circuits at the transistor level. Single-stage, multistage amplifiers, and cascade stage; differential amplifier analysis; operational amplifiers & applications; feedback structures, output stages, and power amplifiers.
Pre-Requisites: EE-251, MTH-112, and PHY-202.
Repeatable: No
Lecture: 3 hours per week
Lab: 3 hours per week
This course includes both lecture and lab. I will be doing the lecture and the laboratory. The syllabus (2019 on) includes the laboratory exercises. Note also that there are several supporting documents included as appendices at the end of the Syllabus document. These include a discussion of impedance, a comparison of three different amplifiers using PSPICE, the design of Butterworth filters, and the schematic for the MK484 RF amplifier device. The documents listed below the syllabus commenting on Labs 2, 3, and 4 are best appreciated after performing and those exercises and submitting a report. (They are from previous offerings of this course.) Additional documents will be added on this site as needed. As of this writing most of the material is from the 2019 offering, but will be replaced by newer material as soon as possible for the 2023 Fall offering.
This syllabus is for the Fall 2024 offering of EE252. The syllabus includes:
The syllabus with schedules of topics covered in the lecture, lab assignments, policies, etc.
The laboratory exercises
Handout concerning input impedance (how to design to get a desired value)
Handout comparing similar simulated common emitter, cascode and differential amplifiers
Handout on Butterworth Filter Design (applicable to Lab #7)
Handout on MK 484 RF amplifier IC Internals
Supplementary suggestions on documenting design
EE252 Syllabus, Fall 2024
These are my reference notes for this class. They are not required that students download these or even look at them, but they are there in case someone wants to see what I might have been talking about. In an earlier era I used to put these on reserve in the library. Keep in mind that these were my own preparation for the classes, not necessarily capturing everything I said or did. I expect to also include here selected example problems and illustrations. This part of the page will be expanded as I get to things during the Fall 2023 semester.
We will cover Neamen Chapters 7, 8, and 12 thoroughly. Frequency response, feedback, and secondarily power are the most important topics we cover. Our coverage of op-amps is less extensive because you meet and use op-amps in other courses, notably Mechatronics and Circuits. Here is what you need to read in those chapters before we tackle Chapter 12, feedback. Beyond that, at least browse through these chapters and see what's there. There's good stuff, but we cannot do everything. If you need to use this material, you can pick it up later more easily than, say, frequency response and feedback.
Chapter 9: sections 9.1 to 9.5.3, and 9.5.5, 9.7.1, 9.7.3
Chapter 10: sections 10.1.1 to 10.1.2, 10.2.1, 10.3
Chapter 14: sections 14.1 to 14.2, 14.4, 14.5
Chapter 15: sections: 15.1
Feedback is, along with frequency response, the heart of what EE252 covers, and the principles are very important far beyond the electronics context. Feedback use is pervasive in engineering systems. The intent is tocover the topic rigorously, somewhat expanding beyond the Neamen textbook Chapter 12. There are three handouts listed above:
Feedback introduction: These notes are based on Jaeger's book, Chapter 17. It's introductory, and deals with H parameter models (essentially op-amp basics) as a way to get started.
Feedback Problems: These notes show how easy it is to have problems if taking a naive approach. Two-port models assume that the ports are independent; current in one port can't come out the other, at eithter terminal. A simple BJT problem can even lead you asteray.
Examples: These notes take the same amplifier (differential) and the same feedback circuit (R pi network) and use them in series-series, shunt-shunt, and shunt-series configurations. with both analytic and PSpice solutions. After mastering the basics with H parameters, this is where to go next.
This is stuff that doesn't exactly fall in either the lecture notes or lab support categories. The first of these is a look at the AI " Large Language Model " doing a design problem. It doesn't do very well. As is usual, a lot can be learned from failure modes. I'm allowing students to use ChatGPT for preparing lab reports. But, Beware! I think you will find that it can be helpful, but it will take a good bit of work to get it to give you something satisfactory. Take a look at this document, and you will see what I mean. But, I am expecting to find out that there are ways and places such tools will be useful, especailly in the future when improved.
What does Chat GPT Really Know?
The following is an "Introduction to Op-Amps" written for EE217 which may be helpful when we get to op-amps in EE252. This document is just looking at the op-amp as a unit, but in EE252 we will be diving inside to see how it works. The big issue is that for an integrated circuit, transistors are cheap, resstors are not, capacitors are very expensive, and you don't even want to think about inductors. In the world of discrete components, resistors are cheap, transistors versus capacitors is contested, and inductors are expensive but not necessarily prohibitive. That changes the way we design circuits. For example, we use transistor current sources instead of resistors.
EE217 Introduction to Op-Amps
The following is an interesting feedback instability example worked as a PSpice exercise. It is a multistage amplifier (CC + CE + CC) with three capacitors along the signal path and another as the emitter bypass for the common emitter stage. The capacitor calculated frequencies (using the open capacitor model) are all in the 50 to 10 Hz range. This example demonstrates what can happen! You won't see it even in PSpice unless you are patient, and run your simulation for a good long while relative to the frequency of interest.
EE252 Instability in feedback example
This will be supplemented as we go during the semsester