Description
ECE 345: Introduction to Electrical Engineering Laboratory is a 1-credit course taught at Michigan State University for non-Electrical and Computer Engineering majors. There is one 3-hour lab per week. The catalog description for this course is: Electrical and electronic components, circuits and instruments. Circuit laws and applications, frequency response, operational amplifiers, semi-conductor devices, digital logic circuits, microcontrollers. The prerequisites for this course are current enrollment or completion of a first semester calculus.
Lab Manual and e-Notes
The lab lectures consist of e-Notes explaining the ideas and concepts of each lab experiment based on the principles taught in the lectures of ECE 345. These lectures are recorded and can be found on the ECE 345L YouTube channel at: https://www.youtube.com/user/ECE345Lmsu
The lab experiments are intended to teach measurement techniques as well as reinforce concepts taught. As you complete each task in lab you will be asked to record, calculate and evaluate your data. You cannot go on to the next step or circuit unless each task is completed as stated in the lab experiment. This method emphasizes accuracy over speed.
Table of Contents
Lab I – Introduction to the Oscilloscope, Function Generator and Digital Multimeter
PURPOSE: The oscilloscope, function generator and digital multimeter are the basic tools in the measurement and testing of circuits. This lab introduces the first time operation of these instruments.
The concepts covered are:
1. the resistor color code;
2. accuracy of components and the digital multimeter.
The laboratory techniques covered are:
1. voltage amplitude and time measurement with an oscilloscope;
2. measurement of resistors;
3. measurement of resistance using a 4-wire probe.
Lab II – Introduction to Prototyping Circuits
PURPOSE: This lab looks at techniques for measuring source resistance. It also introduces the use of a Proto-Board for the quick assembly of a circuit without the need to solder wires.
The concepts covered are:
1. accuracy of the InfiniiVision;
2. measuring source resistance in linear circuits;
3. terminating cables to suppress reflections;
4. poles and throws of switches;
5. battery performance and characterization;
6. microphone characterization.
The laboratory techniques covered are:
1. using the InfiniiVision’s Automatic Parametric Measurement feature to measure peak-to-peak voltages;
2. re-programming the function generator’s calibration for High Impedance loads;
3. measuring DC voltage with a digital multimeter.
Lab III – Diode Curve Tracer
PURPOSE: An instrument that displays the V-I characteristics of a device is called a curve tracer. Our scope can be used to make such an instrument.
The concepts covered are:
1. the properties of the ideal operational amplifier;
2. inverting amplifier;
3. V-I characteristics of various types of diodes ;
4. designing a diode curve tracer.
The laboratory techniques covered are:
1. the use of the dual trace feature of an oscilloscope;
2. using the InfiniiVision’s XY plotting feature to plot voltage transfer curves;
3. laying out a complex circuit on a Proto-Board with connections for power and the function generator;
4. using X10 probes for measurement.
Lab IV – Introduction to Microcontrollers
PURPOSE: Microcontrollers are devices that contain much of the same items as a computer such as a CPU (Central Processing Unit) and memory but don’t use a monitor, keyboard or mouse to operate, in general. Microcontrollers are usually used for controlling machines through circuitry called hardware and a set of instructions called software programs.
The concepts covered are:
1. Programming in PBASIC;
2. Commands: OUTPUT, PAUSE, GOTO and OUT;
3. Commands: INPUT, IN, and IF_THEN;
4 Boolean operator: OR;
5. Commands: VAR.
The laboratory techniques covered are:
1. the layout of the Basic Stamp microcontroller and the Board of Education manufactured by Parallax, Inc.;
2. writing, editing and downloading programs in PBASIC;
3. using push-button switches as input sensors and LEDs as output sensors.
Lab V – Build Your Own Digital DC Voltmeter
PURPOSE: Analog voltages and currents are continuous with every possible value between two points. Digital voltages and currents have only two possible. A bit is one binary digit that has a value of 0 or 1. It takes many bits to represent a decimal number. In this lab, we will convert an analog voltage into a binary number. This voltage will be converted to a decimal equivalent and displayed.
The concepts covered are:
1. counting in binary;
2. serial data transmission;
3. analog-to-digital conversion;
4 subroutines;
5. commands: PULSOUT, SHIFTIN and DEBUG;
6. fixed and floating point numbers.
The laboratory techniques covered are:
1. using an off the shelf integrated circuit for performing serial analog-to-digital conversion;
2. accuracy and resolution.
Lab VI – Serial Liquid Crystal Display
PURPOSE: Displaying text and data can also be done with a display module. This module has its own microcontroller to manage the display. In this experiment we will use a 2 x 16 display which means 2 lines with 16 characters per line.
The concepts covered are:
1. displaying text and data;
2. command: CON;
3. asynchronous serial data transmission;
4 command: SEROUT;
5. command: FOR_NEXT.
The laboratory techniques covered are:
1. using an off the shelf liquid crystal display to display text and data.
Lab VII – Entertainment System: MP3 Player Power Amplifier, PA System and Mixer.
PURPOSE: Most students have a SmartPhone (MP3 player). Docking this portable music player into a low cost entertainment system would be desirable for many students.
In this lab, we will be building a power amplifier that can be used to drive a speaker so that you can listen to your player without using headphones. We will also build a mixer that will allow us to combine our player with a microphone or any other source of sound.
The concepts covered are:
1. current limit of an op-amp;
2. non-inverting amplifier;
3. V-I characteristics of an NPN and PNP bipolar transistor ;
4. stereo-to-monaural conversion;
5. mixing with an inverting summer.
The laboratory techniques covered are:
1. triggering;
2. using averaging to reduce noise pick-up;
3. using high-frequency noise rejection to improve triggering;
4. measuring gain.
Lab VIII – DC Power Supply and Regulator
PURPOSE: Rectifiers are used to turn an ac voltage with an average voltage of zero into a voltage with a non-zero average value. Adding a large capacitor results in a fairly constant voltage with a small ac ripple voltage. The ripple can be greatly reduced with a Zener diode shunt regulator.
The concepts covered are:
1. transformer turns ratio relationships
2. half-wave rectification;
3. half-wave rectification with capacitive smoothing;
4. Zener diode shunt regulator.
The laboratory techniques covered are:
1. using the InfiniiVision’s auto measurements to measure average voltages, peak voltages, peak-to-peak voltages and frequency;
2. using the InfiniiVision’s Math Functions to differentiate a capacitor voltage to estimate the maximum repetitive diode current.
Lab IX – Light Activated Exhaust Fan
PURPOSE: One use of bipolar junction transistors (BJTs) is to switch circuits on and off. Switching various loads on or off can cause problems especially when the load is inductive. Sometimes the load contains a large amount of energy and isolating this from the control circuitry is very important especially in the case of a component failure. Sensors play a role in many electronic circuits. In this lab we will use a light sensitive resistor to sense a smoke filled room and turn on an exhaust fan. When the room is again clear of smoke it will turn off the fan. This type of photo-resistor is also used in auto-focus cameras, street lamp switches and contrast controls for TVs.
The concepts covered are:
1. the bipolar logic inverter;
2. switching resistive and inductive loads;
3. using a damping diode to discharge a coil;
4. using a relay for load isolation;
5. using a photo-resistor as a sensor;
6. using a magnet to activate a circuit.
The laboratory techniques covered are:
1. Using a x10 probe to measure a BJT’s breakdown voltage;
