lecture 1:basics

Oscilloscope & SPICE Basics

Lecture outline

Course Goals/Outline

The Oscilloscope

P-SPICE

Download

Basic Circuits

Lab Exercise

Reading: 1.TDS200 manual pp.1-64

2. EIL pp.145-2083. SPICE Ch. 1&2

course outlineC1 W 8/25/10 Scope Usage & SPICE

C2 W 9/1/10 Scope Usage & SPICE-Computer Lab

C3 W 9/8/10 Scope Usage & SPICE

C4 W 9/15/10 Op-Amp Characteristics

C5 W 9/22/10 Op-Amp Characteristics

C6 W 9/29/10 Timing & Pulse Circuits

C7 W 10/6/10 TIming & Pulse Circuits

C8 W 10/13/10 Audio-Amplifier

C9 W 10/20/10 Audio-Amplifier

C10 W 10/27/10 DC-DC Converter

C11 W 11/3/10 DC-DC Converter

C12 W 11/10/10 Signal Generator

C13 W 11/17/10 Signal Generator

C14 W 11/24/10 Active Linear Filters

C15 W 12/1/10 Active Linear Filters

•Learning by doing•Laboratory exercises will frame the subject matter•Integrated Approach•Experimental, simulation and theory

gradingLab Demonstrations -30%

Prelab & Demo

Lab Reports & Lab Notebook -30%

Notebook is like 1 report

Exams-30%

In-class or take home

In-class quizzes-10%

Surprise quizzes

Recitation attendance is mandatory

Grade penalty in syllabus

course goals

1. Look at a schematic of an analog circuit and qualitatively predict what the circuit does.

2. Use P-SPICE to perform detailed analysis of the circuit

3. Do back-of-the-envelope calculations to analyze the circuit

4. Derive the transfer function of a simple circuit with emphasis on amplifiers-frequency response.

5. Sketch Bode plots of this circuit

6. learn how to write proper lab reports

Lab reports

Introduction

Theory

Experimental

Results / Discussion

Conclusions

References

Introduction

The introduction is exactly what it says. It is a paragraph or series of paragraphs that introduce the reader to the subject

The introduction presents basic background material, the history of the problem, or introduces most of the major references

Provide a schematic as well

Use formal language. A conversational style is NOT acceptable (see example of tech memo)

Theory (or background)

Explains the theory behind the work and is the proper place for the mathematics

Contains the general equations that describe the system under study

experimentalExplanations for the apparatus, instruments, calibrations, etc.

Expected error and repeatability can be introduced

Describe what you did in the simplest way possible

Diagrams are always helpful

Results/discussion

All results of the lab activity are reported here

This includes simulation and experimental results

Appropriate tabular and graphical form should be used

All x-axis and y-axis scales should be clearly indicated (e.g., current probe measurements y-axis scale) along with UNITS!!!

It is encouraged that you mark the scope captures with a pen showing relevant features or noting numerical values of significance. It is understood that for a formal report you would use some kind of CAD program to mark the figures

results/discussion

All results should be discussed and compared with theoretical predictions and simulation results

Discrepancies should be noted and an attempt to explain them should be made

Are these the results you expect? Why?

Do you notice discrepancies? What is causing these?

conclusion

The conclusions should be a specific and factual summary of the report

The conclusions should tie-up loose ends from the previous portions of the report such as speculation and questions, and analysis of the error.

rubric for lab report

rubric for lab report

the oscilloscope

Oscilloscope displays voltages visually

Coupling-AC, DC and GND

Triggering-tells scope when to start displaying

Analysis & Measurement utilities

In the old days was all-analog

Nowadays digital

analog o-scope

Like a TV in many ways.

subsystems

Display-analog or digital, LCD, CRT etc.

Time-base, x-axis control-Trigger-int. or ext.

Signal, Y-axis control-input, coupling

Power supplies-fuses etc.

Probes 1x, 10x etc. attenuation amount

Calibration circuits -compensate input R, C

triggering

Triggering allows the oscilloscope to be in sync with the signal you’re displaying, so you have a nice steady image.

f(signal)=Nf(trigger signal i.e. x-axis time sweep)

N is an integer or a fraction.

Sampling

Digital o-scopes are not continuous

Each screen has a fixed # of samples

How many for TDS200?

Smapling rate changes with time base

If sampling is too little, aliasing can occur

Like wheel turning backward in car commercials

What determines minimum required sampling?

triggeringCan be made to be one-shot to capture single events.

How can you do this?

This will be the exercise for the first lab

capture a manual switch event.

ORCAD P-spiceSPICE is a circuit simulation program-industry standard

You create a circuit

different circuit editors

Then you simulate it!

Gives you currents, voltages, transients etc.

Download student version on your own computerhttp://www.electronics-lab.com/downloads/

schematic/013/

P-SPICE TIPS

Need a ground!

ONLY use the “0” source in power sources

Make sure you add the required libraries

There are 3 ways to simulate

Text editor

ORCAD Capture

ORCAD Schematic

p-spice Resources

http://www.uta.edu/ee/hw/pspice/

http://www.youtube.com/watch?v=dZUPBLNuaHk

This is for Capture

The download page also has many resources

I will post a SPICE reference also.

work through prelabSwitch debouncer