Digital oscilloscopes are rightly considered among the most valuable tools that engineers can have at their disposal. It is a type of instrument that has long proved its relevance for such tasks and processes as designing embedded systems, troubleshooting power electronics, and maintaining industrial equipment.
This usefulness is maximised by the fact that the latest digital oscilloscopes offer so much more than simple waveform visualisation.
5 Features to Know About in Your Search for an Oscilloscope
The advanced measurement and analysis capabilities of the oscilloscopes available on the market today can bring dramatic benefits for troubleshooting efficiency and design validation.
However, if you’re reading this as an engineer who is looking to select the right oscilloscope, you’ll need to understand the features of this instrument that directly impact on measurement accuracy and usability.
So, as you whittle down your options for an oscilloscope, here are some of the key features you ought to familiarise yourself with.
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Bandwidth
There aren’t many oscilloscope specifications that are as important as the bandwidth. This term refers to the maximum frequency range that a given oscilloscope can accurately measure.
A good broad guideline is that an oscilloscope’s bandwidth should be at least five times greater than the highest-frequency component the user intends to analyse.
So, for instance, if the engineer is working with a 20 megahertz (MHz) clock signal, it is typically a 100 MHz oscilloscope that will provide a more accurate representation of the waveform.
In the event of a particular oscilloscope not having enough bandwidth for the intended task, this can distort measurements. So, the user may be left with the impression of rise times being slower, and signal amplitudes lower, than they actually are.
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Sample Rate
The sample rate determines the number of times the oscilloscope captures data points from a signal. It is normally expressed in Samples per second or GigaSamples per second (Sa/s or GSa/s).
A higher sample rate provides greater waveform detail while lessening the risk of aliasing, which refers to the situation of high-frequency signals appearing incorrectly on the display.
It is typical for modern digital oscilloscopes to offer sample rates ranging from hundreds of MegaSamples per second (MSa/s) to several GSa/s, depending on the application.
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Memory Depth
The amount of waveform data that an oscilloscope is able to store during acquisition, is known as its memory depth.
Memory depth effectively determines how long the user can record while maintaining the maximum sample rate. In this respect, it is governed by the formula: Memory depth = sample rate x time duration.
This specification is a particularly crucial one to account for when users intend to capture long-duration events at the same time as maintaining high sample rates.
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Number of Channels
An oscilloscope with a higher number of input channels can be used to observe a greater number of signals simultaneously.
As far as many general-purpose tasks are concerned, a two-channel oscilloscope will be sufficient.
But for applications that necessitate many more signals being observed at the same time, encompassing the likes of embedded development and power electronics, it is typically four-channel oscilloscopes that are preferred.
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Triggering Capabilities
The capture and stabilisation of specific events on screen is made possible by the given oscilloscope’s triggering function.
Basic edge triggering captures signals at the point of them crossing a predefined voltage threshold. Today’s latest digital oscilloscopes, though, can provide triggering options of much greater sophistication, including such possibilities as pulse width triggering, runt pulse triggering, logic triggering, and more.
If a given oscilloscope boasts advanced triggering capabilities, this will allow an engineer using the instrument to isolate rare or intermittent events that would otherwise be tricky to capture. As a result, debugging time could be greatly shortened.
Final Thoughts: Think Carefully About What You’ll Require from Your Oscilloscope
There isn’t any single oscilloscope that will be the right match for every conceivable application. The right choice in your own search, then, will hinge on such factors as the signals that are to be measured, the complexity of the system under test, and your probable future requirements.
Amid the ever-increasing complexity of digital systems during the 2020s, a well-equipped digital oscilloscope will be one of the best investments you could hope to make as an engineer. This will be particularly the case when you need to undertake accurate testing, efficient troubleshooting, and successful product development.
