Undergraduate Analog I.C. Design - ENEL 465
Welcome to ENEL 465, a course that deals primarily with analog
and some CMOS circuit design issues. In this course, we examine
blocks for IC design, and then we build a bipolar Operational Amplifier
using discrete components in the lab.
We also examine applications of linear integrated circuits,
waveform generators, power supply voltage and current regulators, and a
variety of other IC's.
The course outline can be examined by clicking here
and the lab schedule is found here.
- The student
PSPICE can be downloaded here.
file is 27 MBytes). When you install this program, do not install the
Capture program, only PSPICE A/D and Schematics. The full commercial
of Cadence PSPICE is available on the departmental CITRIX Server. Note,
that once you run a schematic on the commercial version, it cannot be
on the student version. I recommend using the student version
if you plan on moving files between home and school.
NOTE! In all of the work we do in ENEL465,
we use a simplified small-signal model for the bipolar transistor that
ignores the feedback resistance between collector and base. While this
simplifies the calculations considerably, it will lead to errors of up
to a factor of two in some quantities such as output resistance, etc.
textbooks and PSPICE itself also make this approximation, but the
should be aware that it is not strictly correct. In some instances,
as switching regulator design, this simplification leads to
results, so one must proceed with caution, particularily when accepting
PSPICE results at face value. For our work in this course, the
predictions are well within the limits of variability between devices
the practical sense, and we will ignore this feedback element at all
Modules for ENEL 465 Please note: Due to some
problems, the dynamic links in these modules may not work correctly. To
avoid the problem, download the Visual Basic executables from the
of this page, and also download the VBrun300.dll
and VB40032.dll files and put them in the
directory. Then double click on an executable to run it. To run the
schematic files, download them directly from the bottom of this page,
also download the Bipolar465.lib file.
the .lib file in C:\Program Files\Orcad_Demo\PSPICE\library on your
machine. Then in PSPICE, open the analysis menu, choose library and
files, and add the .lib file globally. The schematics should then run
Operation of the Bipolar Transistor
- The purpose of this module is to
reader to the physical
- operation of bipolar transistors.
views of a BJT are
- provided, along with graphic
displays of minority
- and their dependence on base-emitter
bias. A simple
- Visual Basic program is included to
animation of device behavior.
This module describes the basic static and small-signal
- of bipolar transistors that are important for analog circuit
This module describes the basic commands and actions required
to draw and
- simulate a circuit schematic in PSPICE. It is intended for
new and novice
- For a more detailed description of program operation, see
- that are supplied with the program.
PSPICE Bipolar Transistor
- This module describes the basic model parameters for
- that are used in OrCad's PSPICE program, and relates the
- Ebers-Moll model to the more sophisticated models used in
This module describes the basic behaviour of unity gain current
- mirrors that are used extensively in analog IC design as
- biasing sources and as high resistance active loads.
- This is a basic lesson dealing with a fundamental building
- block for monolithic integrated circuits. The ideal circuit
- covered, and Early Effect is included as the main
- in the circuit.
This module examines the basic bipolar opamp that is
in lab experiment #2.
Plots and Operational Amplifier Stability
This module describes the theory behind Bode Plots, and
- usefulness in determining the stability of negative feedback
- using operational amplifiers. A useful visual basic program
- to help the reader to develop a feeling for the issues
- This lesson deals with a circuit that provides a variable
- frequency based on a varying voltage, or by varying resistors
- in the circuit.
Phase Shift Oscillator
- This lesson deals with a sinusoidal positive feedback
- that uses all-pass networks to achieve variable phase shift
- easy adjustment of oscillator frequency. An Automatic Gain
- (AGC) circuit is used to stabilize the output amplitude.
This module describes the linear transistor-based voltage
- regulators commonly used in North American Vehicles.
This module describes the basic theory behind switching
- regulators, with emphasis on step-down (or Buck) regulators.
- Commercial circuits and software are also examined.
This module describes the basics of crystal oscillator
- design, for clock generation and other applications.
- equations are presented for determining the frequency of
- oscillation and the power dissipated in the crystal.
for Troubleshooting Circuits
- This module describes some basic techniques for
- analog electronic circuits in the laboratory.
The DOS analog active filter design
be downloaded by holding down the shift key and clicking here.
- These are the files
for the PSPICE
orientation Lab: npnmodelpnpmodel
Here are links to some of the major manufacturers of linear
The Visual Basic
that appear in the lesson plans can be downloaded by clicking on the
below. These are stand alone programs, but to run them you must have
available to your system. If you don't have it, download it from my
The programs below can be
and run directly if you also download VBRun300.dll and VB40032.dll (see
top of page) onto your local
- Widlar Source Module- programs to calculate circuit gain
current with and without Early Effect:
- Visual Basic Program to
transistor operation AnimatedBipolar.exe
- Visual Basic Program to Calculate Common Emitter
using PSPICE Parameters Beta.exe
- Visual Basic Program to Examine Basic Bode Plots Basicbode.exe
- Visual Basic Program to Examine OpAmp Negative
Circuit Stability Bode.exe
- Visual Basic Program to Calculate the Frequency of
Oscillation of the
Waveform Generator Circuit Vfc.exe
The PSPICE files that are
in the lesson modules can be downloaded by holding down the Shift key
clicking on the links below.
This is the TI macrocell library for OPAMPS and COMPARATORS:
that this is a DOS library, but the models can be used in PSPICE for
- If you don't have PKUNZIP for windows 95 and NT, download it
by clicking here.
If you need PKUNZIP for DOS, download it by clicking here.