Analog Discovery 3 - What makes it different?

As many are likely aware, Digilent has unveiled the Analog Discovery 3 (272-8596) . Many customers have asked the question- "How does the Analog Discovery 3 stack up against its predecessor, the Analog Discovery 2 (134-6480) ?" 

In this post, we'll meticulously delve into the differences and modifications that set these two devices apart. Let's begin with the areas where the Analog Discovery 3 shows improvement. 

Key Features:

MSRP: The Analog Discovery 3 retails for $379 USD, a reduction of $20 from the previous Analog Discovery 2's price of $399.

Sample Buffer Size: The most substantial hardware enhancement in the Analog Discovery 3 stems from the inclusion of a Spartan 7 FPGA instead of the Spartan 6, resulting in a doubling of sample buffers for data collection. While the Analog Discovery 2 was limited to a maximum of 16,384 samples of analog and digital data per channel (depending on your chosen Device Configuration), the Analog Discovery 3 can now acquire or send out up to 32,768 samples at the full sample rate per channel. Larger data capture capacity does require users to analyze more extended sequences of complex data, which could be precisely what you were hoping for. 

Notably, minimum sample buffers have been increased across the board. In the Analog Discovery 2, selecting Configuration 4, which increased the Logic Analyzer and Pattern Generator to their maximum sample size, detrimentally affected the analog channels. In contrast, the Analog Discovery 3 ensures that all systems, both analog and digital, have at least 2,048 samples to work with, regardless of the chosen configuration. 

Modulation Parameters: The Analog Discovery 3 also brings a welcome boost to the FM and AM parameters of the modulation feature of the Arbitrary Waveform Generator. Instead of limited options and lower resolution, the Analog Discovery 3 now offers a minimum of 2,048 samples at 16-bit resolution for both FM/PM and AM/SUM, along with even larger sample sets of 8,192 samples at 16-bit resolution in configuration 6. A significant improvement indeed. 

Digital Loopback: The Analog Discovery 3 introduces the capability to digitally capture and view analog data between the Oscilloscope and Arbitrary Waveform Generator, a feature occasionally requested for its predecessor. Users can now easily echo an analog signal received on the Scope with different amplitude and offset settings, or visualize the signal generated by the Arbitrary Waveform Generator alongside the attenuated signal after passing through a filter. 

Hardware Filters: The Analog Discovery 3 takes it a step further by offering on-board hardware filters that can smooth out incoming signals, making it easier to work with your data. This feature simplifies the process, particularly when dealing with modulation and signal generation in the Waveform Generator. 

Sample Rate: The Analog Discovery 3 takes sample rate control a step further, allowing users to adjust its System Clock Frequency from the default 100 MHz to values as low as 50 MHz and as high as 125 MHz. This enables faster sampling rates and greater flexibility in data acquisition, unlike the Analog Discovery 2, which was locked at 100 MHz. 

DIO Pin Settings: The Analog Discovery 3 gives users the ability to change the internal pull resistor type for all of its digital I/O pins, offering enhanced control and versatility. 

Power Supplies: The programmable user power supplies on the Analog Discovery 3 have increased their current output for both channels from the Analog Discovery 2's 700 mA or 2.1 W per channel to 800 mA or 2.4 W for both the 5 V and -5 V supplies. This provides extra headroom for power supplies and makes it easier to control them directly from the Waveform Generator instrument. 

Features remaining the same

Now, let's touch on the aspects that remain the same between the two devices. 

Software Support: WaveForms, WaveForms SDK, MATLAB, LabVIEW - all the software support that users have come to appreciate with the Analog Discovery 2 is fully compatible with the Analog Discovery 3. 

Backwards Compatibility: Migrating projects from the Analog Discovery 2 to the Analog Discovery 3 is generally straightforward, with 98% to 99% of projects able to make the transition without issues. Users can easily open existing workspaces with the Analog Discovery 3, maintaining compatibility. The small percentage of users who may face challenges includes those with WaveForms SDK applications hardcoded for the Analog Discovery 2, those reliant on the embedded audio jack of the Analog Discovery 2, and users who utilized the 1.8 V Digital input setting. 

Resolution: Both the Analog Discovery 3 and its predecessor feature 14-bit resolution on their analog inputs and outputs. The Analog Discovery 3 improves the noise buffer on the Oscilloscope to 14-bit resolution, whereas the Analog Discovery 2 offered 13-bit resolution. The Scope inputs also support 15 and 16-bit resolution at lower sample rates. 

Communication with Host PC: While the Analog Discovery 3 incorporates a new USB Type C® port for improved connectivity and a higher-rated power spec, it still uses USB 2.0 for communication. However, features that were limited by the USB 2.0 rate have seen improvements, such as the maximum Record rate, which has increased from 1 MS/s to up to 10 MS/s for a single channel. 

Features no longer available

Now, let's explore the aspects that are no longer available with the Analog Discovery 3. 

Audio Jack: The Analog Discovery 3 no longer features an embedded audio jack. The functionality it offered is now found in the Audio Adapter+ with its stereo inputs and outputs. 

Hardware Design Guide: The Hardware Design Guide for the Analog Discovery 3 is not available, as the R&D group opted not to recreate it. Users with hardware capability questions can turn to the Test and Measurement section on the Digilent Forum for assistance. 

1.8 LVCMOS Digital Input Support: The Analog Discovery 3 removed support for the 1.8 LVCMOS digital input option. 

In summary

The Analog Discovery 3 presents numerous improvements and enhancements over its predecessor, offering a lower price, larger sample buffers, digital loopback, hardware filters, and flexible sample rate adjustment