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EXPERT SYSTEMS AND SOLUTIONS

Email: expertsyssol@gmail.com

expertsyssol@yahoo.com

Cell: 9952749533www.researchprojects.info

PAIYANOOR, OMR, CHENNAI

Call For Research Projects Final

year students of B.E in EEE, ECE, EI,

M.E (Power Systems), M.E (Applied

Electronics), M.E (Power Electronics)

Ph.D Electrical and Electronics.

Students can assemble their hardware in our

Research labs. Experts will be guiding theprojects.

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Theory of

Oscilloscope

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Introduction

What is an oscilloscope?

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Introduction

A graph-displaying device of electrical signal

X axis: Time

Y axis: Voltage

Z axis: Intensity or brightness

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Introduction

Information given by oscilloscopes

Time and voltage

Frequency and phase

DC and AC components

Spectral analysis

Rise and fall time

Mathematical analysis

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What can you do with

oscilloscopes?

Designing and repairing electronic equipment

With the proper transducer (Ex: microphone)

Electrical signal in response to physical stimuli,

such as sound, mechanical stress, light, or heat.

Engine vibrations

Brain waves

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Control panel ofan

oscilloscope

Vertical Section

Horizontal Section

Trigger Section

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Basic setting

Vertical system

attenuation or amplification of signal (volts/div)

Horizontal system

The Time base (sec/div)

Trigger system

To stabilize a repeating signal and to trigger on a single

event

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In digital circuits

Measuring

Logic level

Timing Logic strength

Rise and fall time

Frequency

Signal integrity

Waveform distortion

Noise level

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In digital circuits

Diagnosing

Timing fault

Proper fan-in and fan-out Proper pull-up and/or termination

Collision

Signal integrity

Reflection

Noise, crosstalk and ground bounce

Open, short or stuck at 0 or 1

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Analog and digital

oscilloscope

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Analog oscilloscope

Real-time display of signals

Block diagram

Sweep generator and vertical amplifier

Earthquake recorder

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Digital oscilloscope (contd.) Sampling

Interpolation

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Advantage ofDigital Scope

Trend towards digital.

Easy to use.

One-shot measurement

Recoding

Triggering

Data reuse

Connectivity

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Probes

Components

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Probes

High quality connector

High impedance (10M;)

50; for high frequency measurement

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Passive probe

10v attenuation

Good for low circuit loading

Suitable to high frequency signal Difficult to measure less than 10mV

signals

1v attenuation

Good for small signals

Introducing more interference

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Active probe

Signal conditioning oscilloscope

Require power source

Good for high speed digital signals over100MHz clock frequency