THE CITADEL, THE MILITARY COLLEGE OF SOUTH CAROLINA

171 Moultrie Street, Charleston, SC 29409

Instructional Demos, In-Class Projects,

& Hands-On Homework:

Active Learning for Electrical Engineering

using the Analog Discovery

by

Dr. Gregory J. Mazzaro

Dr. Ronald J. Hayne

2

Presentation Overview

• Motivations for Introducing the Analog Discovery into EE Courses

• Key Features of the 1st-Generation Unit Manufactured by Digilent

• Hardware and Software

• Analog and Digital

• Integration of the Analog Discovery into Citadel EE

• Freshman Introduction to Electrical Engineering

• Sophomore Circuit Analysis and Digital Logic

• Results, Feedback, & Summary

3

Why use the Analog Discovery?

(1) to provide hands-on exposure that few EE students receive

in the opening semesters of their major

(2) to introduce electrical wiring/routing, signals, and components

to a student who has not yet studied Ohm’s Law

(3) to provide a way for students to experiment with relatively-harmless

electricity away from the classroom and lab

(4) to integrate such a tool across multiple core EE courses

(5) to familiarize EE students with a tool that they

might use to complete assignments/designs

that do not require using the Analog Discovery

(6) to accomplish [all of the above] for under $200

• Motivations for Introducing the Analog Discovery into EE Courses

4

Instrument: Hardware

voltage

supply

osc

illo

scop

e

fun

ctio

n

gen

erat

or

multi-

meter

The AD instrument combines the functions

of multiple electronics-laboratory

instruments into a single USB-powered,

PC-controlled, portable unit.

5

Instrument: Hardware

voltage

supply

fun

ctio

n

gen

erat

or

key features: simultaneous +5-V and –5-V fixed supply rails (up to 50 mA)

2 arbitrary waveforms: any DC voltage between –5 V and +5 V

sinusoids & square waves up to 10 MHz

6

Instrument: Hardware

osc

illo

scop

e

multi-

meter

key features: 2 simultaneous analog inputs

100 MSamples/second

automated measurements:

DC (average) voltage

RMS voltage

peak-to-peak voltage

7

Instrument: Software

WaveformsTM

osc

illo

scope

fixed

power

rails funct

ion g

ener

ator

All functionality is

available through a unified

graphical user interface.

8

Instrument: Software

WaveformsTM

multimeter

static input/output logic analyzer

logic pattern generator

All functionality is

available through a unified

graphical user interface.

9

Instrument: Analog

These lines are used in Fundamentals of EE,

Electric Circuit Analysis I and II,

and Electrical Laboratory.

10

Instrument: Digital

These lines are used in Fundamentals of EE

and Digital Logic Design.

11

Freshman Fundamentals of EE

5 V R

+ VD -

ID

+ V

R -

Freshmen become familiar with series &

parallel, breadboarding, measurements, and

verification of Ohm’s Law, KVL, KCL.

A sample exercise from our LED lab:

• Build the circuit shown in the figure.

• Measure the voltages VD and VR .

Tutorials are available at

learn.digilentinc.com .

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Digital I/O

Function IC Pin IC Pin Function Digital

I/O

DIO 9 MR 1 16 Vcc V+

DIO 10 CP 2 15 TC P0 3 14 Q0 DIO 0

P1 4 13 Q1 DIO 1

P2 5 12 Q2 DIO 2

P3 6 11 Q3 DIO 3

DIO 8 PE 7 10 TE V+

GND GND 8 9 SPE V+

Freshman Fundamentals of EE

A sample exercise from our Digital Counter lab:

• Interface the 74HC161 to the Digital I/O pins

as listed in the table.

• Observe the incrementing of binary numbers.

Freshmen become familiar

with clocking, base-2,

and binary counting.

13

Sophomore Electric Circuits

All sophomores who take Circuits receive

2 instruments and a set of components.

MS8217

parts kit

Sophomore Electric Circuits

Written:

Show all work for maximum credit.

1. In Circuit #1, determine the power absorbed by the dependent voltage source.

2. In Circuit #2, determine the voltage v .

Simulation:

7. Simulate Circuit #2 in PSpice.

Submit a printout of your schematic, showing all node voltages.

(Submit this printout attached to the Written portion of the assignment.)

Explain why your simulation confirms your answer to Problem #2.

Project:

8. Build Circuit #2 using your Analog Discovery design kit.

Demonstrate to your instructor that you are able to measure the voltage v

using your multimeter.

(You only need to bring your breadboarded circuit to your instructor’s office.)

Circuit #1 Circuit #2

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Sophomores are required

to breadboard & demonstrate

1 circuit every week.

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Lecture w/ Analog Discovery

instrument

breadboard

multimeter

white-board

overhead-projected

screen

lecture presentation

slides

seen by the students, in class

seen by the instructor,

in class

Demonstrations of breadboarding and

interfacing with instrument(s)

are given by the instructors, regularly.

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Homework Previews

slides distributed

as part of the

weekly course notes

The instructors provide

example layouts and sample signals

before homeworks are due.

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Sophomore Circuits Lab

PRE-LAB:

Complete the following 9 steps before arriving to perform Lab #1.

1. In PSpice, build and simulate (using “Bias Point”) the two-branch

voltage-divider circuit shown in Figure 1.

Figure 1. Voltage divider circuit.

8. Ensure that you have the 5 resistors needed to build the circuit in Figure 1.

Using your MS8217 as a DC ohmmeter, measure each resistor, record its true value, and compute

percent error from nominal. Ensure that no percent error is greater than 10% before proceeding.

9. Construct the circuit of Figure 1.

Add jumpers to your breadboard for the independent voltage source.

Use 1 red wire for “+” and 1 black wire for “–”.

Breadboarding performed

before each lab begins gives

each student more time to

perform diagnostics.

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Sophomore Digital Logic

A classroom demo of sequential logic

replicates the tail-light flashing sequence

of a 1965 Ford Thunderbird.

The design was

written in VHDL and

implemented on a Xilinx FPGA

using a Digilent BASYS board.

Digilent

BASYS

The instructors have found many

ways to demonstrate EE concepts

using the Analog Discovery,

beyond required assignments.

top row: turn signal & hazard inputs

bottom row: tail-light outputs

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Results / Successes

Outcomes required by ABET:

• “an ability to apply knowledge of mathematics, science, and

engineering” -- Students use the Analog Discovery to verify theoretical

results given by KVL, KCL, and calculus.

• “an ability to design and conduct experiments, as well as to analyze and

interpret data” -- Students can now conduct such experiments (partly)

on their own time, in their choice of environment.

• “an ability to use the techniques, skills, and modern engineering tools

necessary for engineering practice” -- Modern EE is performed by

comparing simulations against measurements, such as PSpice vs. Analog

Discovery results

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Results / Successes

Proficiencies demonstrated by our students:

in Fundamentals of Electrical Engineering …

• build a resistor-LED circuit

• measure a DC voltage & calculate a DC current

• build an IC-based counter circuit

• control digital inputs & observe digital outputs

in Electric Circuit Analysis I …

• measure a resistance

• breadboard a resistive circuit

• measure multiple DC voltages; measure a DC current

• build a circuit containing multiple sources / an op amp

• generate and observe a sinusoid & a square-wave voltage

• build an RC/RL circuit; observe an exponential rise/decay

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Feedback & Summary

Feedback reported by students:

from Fundamentals of Electrical Engineering …

• “The course did a good job holding my attention. Everything was

interesting and hands-on.”

• “I enjoyed the hands-on learning style of the labs and lessons.”

from Electric Circuit Analysis I …

• “I enjoyed the demo assignments in the course. Hands-on homework

with the breadboard and PSpice was very helpful.”

• I love the Digilent-Waveforms projects as well as the PSpice

simulations. This really helped me understand key concepts.”

Summary: We demonstrated the integration of the Analog Discovery

across the early EE undergraduate curriculum.

The AD does help to achieve ABET’s stated objectives for EEs

and has received a positive response from students.

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References

[1] Analog Discovery Technical Reference Manual, Digilent Inc., 2013.

[2] Waveforms SDK manual, Digilent Inc., 2015.

[3] Beginner Analog Discovery, Module 1,

https://learn.digilentinc.com/Module/104 , 2016.

[4] Getting Started with the Analog Discovery,

https://www.youtube.com/user/DigilentInc/playlists , 2016.

[5] Digilent Basys Board Reference Manual, Digilent Inc., 2007.