ANALOG DISCOVERY 2

Description

Mitchell_Analog_Discovery_2_featured

Digilent Analog Discovery 2 is a USB oscilloscope and multi-function instrument that allows users to measure, visualize, generate, record, and control mixed-signal circuits of all kinds. Developed in conjunction with Analog Device and supported by Xilinx University Program, Analog Discovery 2 is small enough to fit in your pocket, but powerful enough to replace a stack of lab equipment, providing engineering students, hobbyists, and electronics enthusiasts the freedom to work with analog and digital circuits in virtually any environment, in or out of the lab. The analog and digital inputs and outputs can be connected to a circuit using simple wire probes; alternatively, the Analog Discovery BNC Adapter and BNC probes can be used to connect and utilize the inputs and outputs. Driven by the free WaveForm 2015 (Mac, Linux and Windows Compatible) software, Analog Discovery 2 can be configured to work as any one of several traditional instruments.

Specifications

  • Two-channel USB digital oscilloscope (1MΩ, ±25V, differential, 14-bit, 100MS/s, 30MHz+ bandwidth - with the Analog Discovery BNC Adapter Board)
  • Two-channel arbitrary function generator (±5V, 14-bit, 100MS/s, 12MHz+ bandwidth - with the Analog Discovery BNC Adapter Board).
  • Stereo audio amplifier to drive external headphones or speakers with replicated AWG signals.
  • 16-channel digital logic analyzer (3.3V CMOS and 1.8V or 5V tolerant, 100MS/s).
  • 16-channel pattern generator (3.3V CMOS, 100MS/s).
  • 16-channel virtual digital I/O including buttons, switches, and LEDs – perfect for logic training applications.
  • Two input/output digital trigger signals for linking multiple instruments (3.3V CMOS).
  • Single channel voltmeter (AC, DC, ±25V).
  • Network analyzer – Bode, Nyquist, Nichols transfer diagrams of a circuit. Range: 1Hz to 10MHz.
  • Spectrum Analyzer – power spectrum and spectral measurements (noise floor, SFDR, SNR, THD, etc.)
  • Digital Bus Analyzers (SPI, I²C, UART, Parallel)
  • Two programmable power supplies (0…+5V , 0…-5V). The maximum available output current and power depend on the Analog Discovery 2 powering choice:
    • 500mW total when powered through USB. (Each supply can provide between 0mW and 500 mW so long as the total does not exceed 500mW.)
    • 2.1W max for each supply when powered by an auxiliary supply.
    • 700mA maximum current for each supply.

Analog Discovery 2 is the next generation of the very popular Analog Discovery.
The main improvements are:

  • Ability to use an external power supply and consequently deliver more power to user supplies. When USB-powered, the Analog Discovery 2 delivers the same power as the original Analog Discovery.
  • New enclosure with enhanced design and improved connector reliability.
  • Improved signal/noise and crosstalk performances for both the scope and waveform generator.
  • Better defined bandwidth for both the scope and waveform generator.

Architectural Overview and Block Diagram
DigilentAnalogDiscovery2bd
Analog Discovery 2's high-level block diagram is presented in image below. The core of the Analog Discovery 2 is the Xilinx® Spartan®-6 FPGA (specifically, the XC6SLX16-1L device). The WaveForms application automatically programs the Discovery’s FPGA at start-up with a configuration file designed to implement a multi-function test and measurement instrument. Once programmed, the FPGA inside the Discovery communicates with the PC-based WaveForms application via a USB 2.0 connection. The WaveForms software works with the FPGA to control all the functional blocks of the Analog Discovery 2, including setting parameters, acquiring data, and transferring and storing data.

Signals in the Analog Input block, also called the Scope, use “SC” indexes to indicate they are related to the scope block. Signals in the Analog Output block, also called AWG, use “AWG” indexes, and signals in the Digital block use a D index – all of the instruments offered by the Discovery 2 and WaveForms use the circuits in these three blocks. Signal and equations also use certain naming conventions. Analog voltages are prefixed with a “V” (for voltage), and suffixes and indexes are used in various ways: to specify the location in the signal path (IN, MUX, BUF, ADC, etc.); to indicate the related instrument (SC, AWG, etc.); to indicate the channel (1 or 2); and to indicate the type of signal (P, N, or diff). Referring to the block diagram in image below:

  • The Analog Inputs/Scope instrument block includes:

    • Input Divider and Gain Control: high bandwidth input adapter/divider. High or low-gain can be selected by the FPGA
    • Buffer: high impedance buffer
    • Driver: provides appropriate signal levels and protection to the ADC. Offset voltage is added for vertical position setting
    • Scope Reference and Offset: generates and buffers reference and offset voltages for the scope stages.
    • ADC: the analog-to-digital converter for both scope channels.
  • The Arbitrary Outputs/AWG instrument block includes:

    • DAC: the digital-to-analog converter for both AWG channels
    • I/V: current to bipolar voltage converters
    • Out: output stages
    • Audio: audio amplifiers for headphone
  • A precision Oscillator and a Clock Generator provide a high quality clock signal for the AD and DA converters.

  • The Digital I/O block exposes protected access to the FPGA pins assigned for the Digital Pattern Generator and Logic Analyzer.

  • The Power Supplies and Control block generates all internal supply voltages as well as user supply programmable voltages. The control block also monitors the device power consumption for USB compliance when power is supplied via the USB connection. When external power supply is used, the control block allows more power for the user supplies. Under the FPGA control, power for unused functional blocks can be turned off.

  • The USB Controller interfaces with the PC for programming the volatile FPGA memory after power on or when a new configuration is requested. After that, it performs the data transfer between the PC and FPGA.

  • The Calibration Memory stores all calibration parameters. Except for the “Probe Calibration” trimmers in the scope Input divider, the Analog Discovery 2 includes no analog calibration circuitry. Instead, a calibration operation is performed at manufacturing (or by the user), and parameters are stored in memory. The WaveForms software uses these parameters to correct the acquired data and the generated signals.

Pinout Diagram

analogdiscovery2-pinout-600

Features and Performances

Analog Inputs (Scope)

  • Channels: 2
  • Channel type: differential
  • Resolution: 14-bit
  • Absolute Resolution(scale ≤0.5V/div): 0.32mV
  • Absolute Resolution(scale≥1V/div): 3.58mV
  • Accuracy (scale≤0.5V/div, VinCM = 0V): ±10mV±0.5%
  • Accuracy (scale≥1V/div, VinCM = 0V): ±100mV±0.5%
  • CMMR (typical): ±0.5%
  • Sample rate (real time): 100MS/s
  • Input impedance: 1MΩ||24pF
  • Scope scales: 500uV to 5V/div
  • Analog bandwidth with Discovery BNC adapter: 30 MHz+ @ 3dB, 10 MHz @ 0.5dB, 5 MHz @ 0.1dB
  • Analog bandwidth with Wire Kit: 9 MHz @ 3dB, 2.9 MHz @ 0.5dB, 0.8 MHz @ 0.1dB
  • Input range: ±25V (±50V diff)
  • Input protected to: ±50V;
  • Buffer size/channel: Up to 16k samples
  • Triggering: edge, pulse, transition, hysteresis, etc.
  • Cross-triggering with Logic Analyzer, Waveform Generator, Pattern Generator or external trigger.
  • Sampling modes: average, decimate, min/max
  • Mixed signal visualization (analog and digital signals share same view pane)
  • Real-time views: FFTs, XY plots, Histograms and other
  • Multiple math channels with complex functions.
  • Cursors with advanced data measurements.
  • Captured data files can be exported in standard formats.
  • Scope configurations can be saved, exported and imported.

Analog Outputs (Arbitrary Waveform Generator)

  • Channels: 2
  • Channel type: single ended
  • Resolution: 14-bit
  • Absolute Resolution(amplitude ≤1V): 166μV
  • Absolute Resolution(amplitude >1V): 665μV
  • Accuracy - typical (|Vout| ≤ 1V): ±10mV ± 0.5%
  • Accuracy - typical (|Vout| > 1V): ±25mV ± 0.5%
  • Sample rate (real time): 100MS/s
  • AC amplitude (max): ±5 V
  • DC Offset (max): ±5 V
  • Analog bandwidth with Discovery BNC adapter: 12 MHz @ 3dB, 4 MHz @ 0.5dB, 1 MHz @ 0.1dB
  • Analog bandwidth with Wire Kit: 9 MHz @ 3dB, 2.9 MHz @ 0.5dB, 0.8 MHz @ 0.1dB
  • Slew rate (10V step): 400V/μs
  • Buffer size/channel: up to 16k samples
  • Standard waveforms: sine, triangle, sawtooth, etc.
  • Advanced waveforms: Sweeps, AM, FM.
  • User-defined arbitrary waveforms: defined within WaveForms software user interface or using standard tools (e.g. Excel)

Logic Analyzer

  • Channels: 16 (shared)
  • Sample rate (real time): 100MS/s
  • Buffer size/channel: up to 16K samples
  • Input logic: LVCMOS (1.8V/3.3V, 5V tolerant)
  • Multiple trigger options including pin change, bus pattern, etc.
  • Cross-triggering between Analog input channels, Logic Analyzer, Pattern Generator or external trigger.
  • Interpreter for SPI, I2C, UART, Parallel bus.
  • Data file import/export using standard formats.

Digital Pattern Generator

  • Channels: 16 (shared)
  • Sample rate (real time): 100MS/s
  • Algorithmic pattern generator (no buffers used)
  • Custom pattern buffer/ch.: up to 16Ksamples
  • Output logic standard: LVCMOS (3.3V, 12mA)
  • Data file import/export using standard formats
  • Customized visualization for signals and busses.

Digital I/O

  • Channels: 16 (shared).
  • Input logic: LVCMOS (1.8V/3.3V, 5V tolerant)
  • Output logic standard: LVCMOS (3.3V, 12mA)
  • Virtual I/O devices (buttons, switches & displays).
  • Customized visualization options available.

Power Supplies

  • Voltage range: 0.5V…5V and -0.5V…-5V.
  • Pmax (USB powered): 500mW total
  • Imax (USB powered): 700mA for each supply
  • Pmax (AUX powered): 2.1W for each supply
  • Imax (AUX powered): 700mA for each supply
  • Accuracy (no load): ±10mV
  • Output impedance: 50mΩ (typical)

Network Analyzer

  • Shared instruments: Scope, AWG
  • Frequency sweep range: 1Hz to 10MHz
  • Frequency steps: 5 … 1000.
  • Settable input amplitude and offset
  • Analog input records response at each frequency.
  • Available diagrams: Bode, Nichols, or Nyquist.

Voltmeters

  • Channels (shared with scope): 2
  • Channel type: differential
  • Measurements: DC, AC, True RMS.
  • Resolution: 14-bit
  • Accuracy (scale ≤0.5V/div): ±5mV
  • Accuracy (scale ≥1V/div): ±50mV
  • Input impedance: 1MΩ || 24pF
  • Input range: ±25V (±50V diff)
  • Input protected to: ±50V

Spectrum Analyzer

  • Channels (shared with scope): 2
  • Power spectrum algorithms: FFT, CZT.
  • Frequency range modes: center/span, start/stop.
  • Frequency scales: linear, logarithmic.
  • Vertical axis options: voltage-peak, voltage-RMS, dBV and dBu.
  • Windowing: options: rectangular, triangular, hamming, Cosine, and many others.
  • Cursors and automatic measurements: noise floor, SFDR, SNR, THD and many others.
  • Data file import/export using standard formats.

Other features

  • USB power option; all needed cables included.
  • External supply option: 5V, 2.5A (not included) 5.5/2.1mm connector, positive inner pin
  • High-speed USB2 interface for fast data transfer
  • Waveform Generator output played on stereo audio jack
  • Trigger in/trigger out allows multiple instruments to be linked.
  • Cross triggering between instruments.
  • Help screens, including contextual help.
  • Instruments and workspaces can be individually configured; configurations can be exported.

Software

WaveForms is the virtual instrument suite for Electronics Explorer, Analog Discovery, Analog Discovery 2 and Analog Discovery 2 - NI Edition devices. Compatible with Windows, Linux and Mac OS.
waveforms3-0

WaveForms 2015
WaveForms 2015 PDF

Documentation
Analog Discovery 2 Reference Manual Reference.Digilentinc

Tutorials

1. Getting Started with Analog Discovery 2

2.Measuring An Arduino Servo Signal With An AD2 In LabVIEW

3. Analog Discovery 2 USB Oscilloscope + LabVIEW

4. Using the Oscilloscope with the Analog Discovery 2

5. Using the Network Analyzer with the Analog Discovery 2

6. Using The Power Supplies With The Analog Discovery 2

7.Using the Waveform Generator With the Analog Discovery 2

8.Using the Spectrum Analyzer with the Analog Discovery 2

9.DIY ECG using a Analog Discovery 2 and LabVIEW

10.Adding Nobs to the Analog Discovery 2 Using LabVIEW