Basics of Oscilloscopes

The modern oscilloscope is an invaluable tool used by researchers, engineers, technicians, students and hobbyists to Design, Debug, Deploy and Repair today's electronic designs.  

At its simplest level the Oscilloscope allows users to visualize the behavior of a signal by displaying its voltage over a time period.  But the setup, use, and interpretation of collected data can be overwhelming to many and the wealth of new capabilities enabled by digital oscilloscopes are often unknown.

Using a combination of video and printed material this site is dedicated to providing answers to these fundamental oscilloscope questions.   There are 5 Main Sections

  • Oscilloscope Definitions and Concepts
  • Triggering
  • Signal Integrity
  • Advanced Analysis
  • Connectivity and Data Management

 

Oscilloscope Definitions and Concepts

In this section we review the key terms and specifications, what they mean and why they are important to you.  We also review the key instrument controls and how they operate.

 

What does Bandwidth Mean?

A basic concept in determining what scope you need is understanding the key performance characteristic of an Oscilloscoipe, Bandwidth.   Selecting proper Bandwidth insures reliable and accurate measurements

 

 

Sample Rate Vs Memory Depth

A Digital Scopes ability to make long captures is directly tied to the relationship between the instruments sample rate and memory depth. Explore how the two factors interact and the impact on your measurements

 

 

Horizontal System and Controls

Horizontal controls allow for positioning the signal on the time X axis as well as adjust the time based scaling options

 

Vertical System and Controls

Vertical controls allow for the adjustment of amplitude scaling settings, bandwidth limits and and probe attenuation as well as positioning positioning the signal on the vertical axis.

 

Making your first measurement

Provides and overview on how to quickly and easily start making measurements on your oscilloscope

 

Triggering

In order to clearly display and analyze a signal the instrument needs a consistent start point for data capture. This is called triggering and it is controlled by an instrument's trigger system.

 

Introduction to Triggering

Overview of what triggering is, why it is important, and some key terminology associated with it.

Using Edge Trigger

Edge triggering uses the rising or falling edge of a signal to trigger the oscilloscope.

 

Using Pulse Trigger

Pulse triggering uses the width of a pulse to determine when to trigger the oscilloscope.

 

Using Delay Trigger

Delay triggering is used to trigger when time differences between signal transitions either fail to meet minimum thresholds or exceed maximum thresholds.

 

Using Nth Edge Trigger

Nth Edge Trigger is used to trigger after a defined number of pulses have passed helping trigger on and debug complex serial patterns

 

Using Setup and Hold Trigger

Setup and Hold trigger is used to verify the minimum amount of time that data is stable after a clock transition.

 

Using Runt Trigger

Runt triggering is used to trigger the oscilloscope when a runt pulse fails to pass both the low and high trigger points.

 

Using Serial Bus Triggering

Serial triggering is used to trigger the oscilloscope based on specific behavior, command, or data set found on the serial bus

 

Using Pattern Triggering

Pattern triggering is used to trigger the oscilloscope when multiple signal conditions are met in a digital system.

 

Using Duration Triggering

Similar to pattern triggering, duration triggering is used to trigger the oscilloscope when multiple signal conditions are met based on how long the desired state persists

 

Using Slope Triggering

Slope triggering is used to trigger the oscilloscope based on the rise or fall time of a signal

 

Signal Integrity

To accurately measure your systems behavior requires an understanding of factors impacting your acquisition system like loading, noise, and instrument setup.

Probing Basics

Making connection to your device under test is critical to accurate measurements.  Learn the basics parts of the probing system and what they do.

Probe Compensation

In order to insure system signal fidelity it is critical that probes be compensated to the instrument.  Over or under compensated probes can cause distortions of your measurements and bad results.

Signal Acquisition Techniques

Provide an explanation three main data acusition techniques:  Auto Triggering, Normal Triggering, and Single Shot Triggering and explore why you would use each.

Acquisition Modes

Learn more about the four main acquisition modes:  Normal, Average, Peak Detect and High Resolution and learn the benefits of using each mode.

High Impedance vs. 50 Ohm Impedance

Explains why 50 Ohm impedance inputs can improve signal fidelity on high speed signals by removing reflections caused by capacitance or inductance

AC/DC Coupling

AC Coupling removes the DC portion of a signal making it easier to analyze waveforms that have a large DC offset

 

Current Probes 

A current probe allows for safe and convenient measurements without probing in series with your circuit or adding a shunt.  

 

Differential Probes 

Differential probes allow for a safe means to measure high voltage signals and signals that do not have a reference to ground.  

 

Advanced Analysis

The modern digital oscilloscope can perform many specific analysis tasks that allow the user to get to an answer quickly and easily.

 

Using Standard Measurements

The Oscilloscope comes with many standard measurements to help you quickly get to the root cause of your design problems.

Using Math Operations

Math functions allow you to perform calculations on one or more signals allowing for rapid signal comparison and enabling advanced modeling of more complex waveforms.

Using FFT Analysis

FFT (Fast Fourier Transform) enables you to visualize and analyze time based data in the frequency domain.

 

Using Record Mode

A simplified method for capturing, searching and analyzing waveforms over time.

 

Using Pass/Fail Analysis

Using a easily defined mask the oscilloscope can perform pass fail tests to quickly identify out of bounds conditions on a system under test.

 

Using Digital Filtering

Digital Filtering allows users to separate harmonics from complex compound signals and attenuate the power in certain frequency bands

Using Serial Decode

Serial Decode allows the user to view serial bus traffic in a human readable format.

 

Using Cursors

Use Cursors to make measurements between specific points on a captured waveform.

 

Using Phase and Delay Measurements

Quickly determine the delay and phase between multiple channels using standard delay and phase measurements helps to identify system interactions and timing problems

 

Using High Waveform Capture rate to find an infrequent annomoly

High waveform capture rate limits the "dead time" between aqusitions and increases your probability of caturing infrequent events

 

Using Deep memory to speed debug of your design

See how long record length can allow for longer higher resolution captures speeding time it takes to find elusive problems.

 

Connectivity and Data Management

Saving, moving and sharing data is an important part of the design process.  The modern digital oscilloscope gives you amazing tools to save time

Remote monitoring and control of your instrument with UltraScope

 

Seamlessly connect, control and monitor your scope via USB or ethernet using the RIGOL UltraScope utility.  Perfect for remote control, monitoring, data capture and supporting distributed environments

Connecting UltraScope over the LAN

 

The RIGOL utilities make it simple to connect and configure your scope of Ethernet.  Don't be intimidated to set up a remote monitoring and environment.

Saving CSV Data to USB

Pulling data off of your scope to share with other team members or to utilize in other analysis programs is simple with our download to USB function.

Capturing a screen shot

Easily capture a screen shot via USB directly or via UltraSigma software.  Use capture scope data to share with teammates or for inclussion in test reports.

Create Arbitrary Waves simply from scope data

It is simple to capture a reference waveform from your scope and then generate that signal through your RIGOL Arbitrary Function Generator.  A valuable capability when characterizing receivers, prototyipng, or completing pass/fail manufacturing or stress tests.