ECE 3434 Lab Policy and Charter
1.1 Labs (General)
According to department lab policy, you fail to hand in two or more labs you will be assigned an F in the
course regardless of your class average. Also according to ECE department policy, you must earn at least
60% in both the lecture and lab to pass the course regardless of your class average.
Your lab grade will be computed as follows:
Weekly laboratory assignments 60%
Interim laboratory report 15%
Final laboratory report 25%
Unless otherwise noted, labs will be due at the end of your assigned lab period.
1.2 Labs (Details)
Your task for the laboratory portion of ECE 3434 is to build and test a working prototype of a high
performance audio power audio power amplifier on a printed circuit board (PCB). Beginning with a given
classic Lin architecture design, you will:
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Document your work in a laboratory notebook
Summarize the first part of your work in an interim report to the teacher and the teaching
assistants
Summarize all of your work in a final report to the teacher and the teaching assistants
Order the parts for the amplifier from Digi-Key.com
Draw the schematic diagram of the amplifier with Capture in the Cadence software available on
the ECE computers
Simulate the performance of various aspects of the amplifier performance with PSpice in the
Cadence software available on the ECE computers
Design a PCB for the amplifier with Layout Plus in the Cadence software available on the ECE
computers
Prepare extended Gerber files that define the PCB and send them to PCBexpress.com for
fabrication of the PCB
Populate the PCB with the parts you ordered from Digi-Key.com
Measure the performance of the amplifier and compare it with PSpice simulations
Cadence is a more powerful version of OrCAD software. Although the circuit of the Lin architecture audio
amplifier is too large for the OrCAD 10.0 Demo software loaded on your laptop, the environment and user
interface of the OrCAD 10.0 Demo software is quite similar to environment and user interface of Cadence.
Indeed, a full-blown version of OrCAD could accommodate the amplifier circuit, but you will use the more
powerful Cadence that is available on the ECE computers. Because of the similarity of the environments,
you may find it convenient to access the tutorials in OrCAD 10.0 Demo on Capture and Layout in addition
to those in Cadence.
Although the text by Slone describes audio power amplifiers with the Lin architecture that deliver more
than 500W (per channel) into a 4 load, this laboratory deals with a low-power (12W) demo design by
Slone that keeps the cost of components low even as it relies on the Lin architecture. The particular design
is adapted from one found on page 149 of a second book by Slone, "The Audiophile's Project Sourcebook"
(McGraw-Hill 2002). For convenience, we will refer to this design as the "Slone 12W audio amplifier," or
simply the "Slone amplifier". Again, to keep parts cost low, you may use the power supplies available in
the laboratory rather than constructing your own.
The Lin architecture audio power amplifier is an example of an electronic system: it consists of smaller
individual circuits connected together to function as a high performance audio amplifier. Specifically, this
amplifier consists of three stages connected in cascade: an input (transconductance) amplifier, a voltage
(transimpedance) amplifier, and an output (current) amplifier.
As it happens, the Lin architecture for audio power amplifiers (built with discrete components) is similar to
the architecture of typical operational amplifiers implemented on integrated circuits. By simulating,
building, and testing the Lin architecture audio power amplifier, therefore, you will come to understand a
number of the design approaches used by designers of analog ICs as well as learning practical PCB and
laboratory skills and the principles of operation for operational amplifiers. Thus, you will develop a context
for some of the circuits and concepts treated in the other parts of the course.