Budget Tools Review: Digilent Analog Discovery 3
August 04, 2023
Several years ago I got to try out Digilent’s Analog Discovery 2, which is a fantastically capable computer-based test tool. It can act as an oscilloscope, power supply, logic analyzer, and much more. This June, Digilent released the Analog Discovery 3 (AD3). It features a number of enhancements and backward compatibility with the vast majority of Analog Discovery 2 (AD2) projects.
(Image Credit: Jeremy Cook)
Digilent sent me one of these units to review, and the following are my thoughts on the device after a limited trial. We’ll be giving it away via the contest outlined below.
At $379, this “scope” is the most expensive device I’ve reviewed here so far. However, given its wide range of capabilities, it certainly fits in the category of budget – or perhaps value – test equipment.
The device is about 100mm square and 20mm thick. This is a bit larger than the AD2, though it’s still pocketable, or backpack-able with the included leads in its plastic case. GPIO pins are in the same format as the AD2, with labels on the side instead of the top. Top labels might have been preferable, but the kit includes stick-on labels for your wire leads, as well as a printed sheet that explains things nicely.
(Image Credit: Screencap)
The device’s interface is via a computer program called WaveForms (available on Windows, Linux, or Mac), and I had no problem installing it on my MacOS computer. Here you’re greeted with a wide range of usage options, discussed further on.
In brief, the AD3 has the following capabilities:
- Sample Rate of 125 MS/s
- USB C (2.0)
- Dual 14-bit analog inputs
- Dual ±5V 14-bit analog outputs
- 16 digital I/O pins
- +5V and -5V variable power supplies
- Massive software functionality via WaveForms: Oscilloscope, Waveform Generator, Power Supplies, Voltmeter, Data Logger, Logic Analyzer, Pattern Generator, Static I/O, Spectrum Analyzer, Network Analyzer, Impedance Analyzer, Curve Tracer, Protocol Analyzer, Script Editor
It’s a truly impressive device, which builds upon the AD2. In addition to being backwards compatible with the vast majority of AD2 projects, it can work with the same hardware accessories, such as their BNC adapter.
(Image Credit: Screencap)
The WaveForms software is free, though you’ll need to provide an email address in order to get a download link. A welcome screen includes options for use as a scope, wave generator, power supply, voltmeter, logger logic analyzer, network analyzer, etc. Instruments can be used simultaneously; for instance, you can use the wave generator to create a signal, and read it out on the scope. This multi-tool functionality is extremely powerful, though in some situations different resources may conflict with one another (e.g. the Logic Analyzer and Protocol Analyzer can’t be used at the same time). You can tab through different instruments, or arrange multiple windows on-screen.
WaveForms features a scripting option, and a software development kit allows you to create custom applications in Python, C, and more. While I would have liked to see more keyboard shortcuts, apparently you can create them via scripting, so this isn’t entirely off the table.
Where It’s Appropriate, Where It’s Not
One must consider desk space when using computer-based test equipment. Also pictured, OWON HDS2102S handheld scope. (Image Credit: Jeremy Cook)
The AD3 is clearly a powerful and versatile tool, with a usability/size ratio that’s off the charts. The drawback to this sort of computer-based instrument is the fact that while it might give you access to 14 different test tools (depending on how you count), there’s a practical limitation to how much you want on your screen at one time. Additionally, being able to turn a dial or press dedicated buttons on a traditional scope etc. is typically faster than mousing over to adjust XYZ in WaveForms.
Realistically, if you’re going to use a tool all the time – e.g. an oscilloscope or voltmeter – it would be best to buy a dedicated unit, while using the AD3 for tests that are only needed once in a while. If you don’t know what dedicated test equipment is needed it could be a great way to assess your needs. On the other hand, its scripting capabilities, and ability to interact with computer “stuff,” may make it the preferred tool in some situations, even when dedicated equipment could be justified.
Where this unit would really shine is in electronics education. Students can constantly try out new ideas and techniques, and being able to take your tools anywhere in a backpack is fantastic. On the other end of the lectern, it would also be excellent for online or in-person presentations. In this scenario, presenters can share a computer screen and have ‘scope or other data up without using an external camera.
Bottom Line, Worth It?
AD3 (left), AD2 (right), both attractive options. (Image Credit: Jeremy Cook)
So far, I’ve just scratched surface of how you could use the AD3. The device would be worth buying if you are assessing your test equipment needs, or see a scenario where specifically computer-based equipment would slot in nicely. It’s also an excellent option if you are learning about electronics, or if you often give presentations.
As noted, the AD3 retails for $379, or you can pick up AD2 for $299. Of course, you can also register for the contest below, and potentially get an AD3 for $0!