Calibration

The Analog Discovery 2 is an all-in-one pocket instrument for electronics containing a 2-channel oscilloscope, power supplies, waveform generators, logic analyzers, and more. Along with being factory calibrated, the Analog Discovery 2 can be calibrated once you recieve it so that you can ensure that you are making the most accurate measurements possible.


Inventory


Step 1: Device Manager

In the Settings menu under the menu bar, click on Device Manager to open the device manager window.

Once the Device manager window opens, you can explore all of the features of the device manager.

Device manager window.

In the top half of the window, there are the devices listed that you can use with WaveForms. If you have a device plugged in, it will appear here.

Along with the devices that are plugged in, you can also see two demo modes: Analog Discovery demo mode and EExplorer demo mode.

The Analog Discovery demo mode allows you to see all of the features of WaveForms as if you had one plugged in. For example, if you open the oscilloscope tool, you can see channel 1 and 2 scoping a square and sine wave.

The EExplorer demo mode allows you to do the same thing, but as if you had an Electronics Explorer Board plugged in.

Plug in you Analog Discovery 2 so that is shows up in the device manager. It should show up as “Discovery2”.


Step 2: Rename Tool

The first tool to explore is the rename tool. In the device manager, click on “Rename” at the top left of the screen. Here you can type in a new name for your Analog Discovery 2. You can use uppercase or lowercase alphanumeric characters. For example, we named ours “Kaitlyn”.

 Our new Analog Discovery 2, "Kaitlyn".

Device renamed.

This can be useful if you have more than one device or are collaborating in a large group where there will be multiple devices present.


Step 3: Calibration Window

Next, we are going to explore the calibration feature to ensure the best possible accuracy of the Analog Discovery 2.

In the Device Manager window, click “Calibrate”. This will open the Device Calibration window.

The first tab you will see in the calibration window is the “Calibrate” tab. Here you can see all of the tools that can be calibrated.

Calibrate tab.

There is also the “File” menu where you can save or load an existing calibration file, and the “Reset” menu, which we will talk about later.


Step 4: Device Manager Tabs

Along with the Calibrate tab, there is also the Parameters and References tabs. There are the values that define the existing calibration.

It is highly recommended that you do not manually change those values. Instead, we will do a full calibration using the Calibration Wizard.


Step 5: Device Calibration Wizard

To open the Device Calibration Wizard, click “Wizard” at the top of the Device Calibration Window.

When the wizard opens, you should see the screen like in the figure below, which tells you what you will need in order to calibrate your device. Click Next.

Wizard details.


Step 6: Set up the Circuit

The first thing you'll need to do is calibrate the first waveform generator. To do this, you'll need to connect the waveform generator to your digital multimeter.

Connect the yellow wire (positive end of the waveform generator 1) from the flywire assembly to the positive side of your multimeter. Connect the negative side of the multimeter to a black wire (ground) from the flywire assembly.

Circuit set up.

The complete setup should look like the figure below. With the other end of the USB cable connected to the Analog Discovery 2 attached to your computer.

Complete setup.

Read the value on the multimeter. As indicated by the Calibration Wizard, it should be around 0.


Enter the Value

Enter the value you read off of the multimeter into the Calibration Wizard, and click Next.

Enter calibration value.

Repeat until the Calibration Wizard indicates to move on to waveform generator 2.


Plug in Waveform Generator 2

Create the same setup as before, but for waveform generator 2. To do this, swap out the waveform generator 1 cable (yellow) with the waveform generator 2 cable (yellow cable with white stripe).

Plug in waveform generator 2.


Enter the Value Listed on the DMM

Your entire setup should look like the image below.

Entire setup.

Read the value on the DMM, it should be around 0. Enter this value into the Calibration Wizard and hit Next.

Enter value.

Repeat this procedure until the Calibration Wizard indicates to move on to Oscilloscope Calibration.


Step 7: Zero the Oscilloscope

The next step in the calibration process is to zero the oscilloscope.

Zero the oscilloscope.

The next step will guide you through setting up the circuit.


Set up the Circuit

As indicated by the Calibration window, connect all of the oscilloscope probes to ground.

To do this, connect the orange wire (positive end of channel 1), blue wire (positive end of channel 2), orange wire with the white stripe (negative end of channel 1), blue wire with the white stripe (negative end of channel 2), and the black wire (ground).

Setting up the circuit, top view.

Setting up the circuit, close up.


Wait for the Automatic Calibration

Click Next to start the calibration.

The oscilloscope zero calibration is automatic, so all you have to do is wait for it to finish.


Step 8: Calibrate the Oscilloscope

The calibration we will do next will be for the oscilloscope. The first step is to set up the circuit.

Calibrating the oscilloscope.


Set up the Circuit

Connect the positive ends of the 2 channels of the oscilloscope to waveform generator 1, and the negative ends of the 2 channels of the oscilloscope to ground.

Circuit setup, top view.

Circuit setup, close up view.


Calibrate the Oscilloscope

Click Next to start the oscilloscope calibration. This is another automatic calibration, so you'll just need to wait for it to finish.


Step 9: Calibrate the Positive Power Supply

The next thing we'll need to calibrate are the power supplies, starting with the positive one.

Connect the red wire (positive supply) to the positive probe of the DMM. Connect a ground wire to the negative probe of the DMM.

Connect positive supply and ground to DMM.


Setting up the Circuit

The circuit setup should look like the figure below.

Circuit setup.

Read the value off of the DMM. As indicated by the Calibration Wizard, it should be around 1.


Enter the Value

Enter the value into the Calibration Wizard and hit Next.

Enter the value.

Repeat that procedure until the Calibration Wizard indicates to move on to the negative power supply.


Step 10: Connect the Negative Supply

Replace the red wire (positive supply) with the white wire (negative supply).

Connect the negative supply.

Repeat the same procedure used on the positive supply until the calibration window indicated that you are finished.


Press Finish

To complete the calibration, press Finish.

Select Finish.


Step 11: Apply the Changes

In the Device Calibration window, click Apply to confirm the changes.


Step 12: Compare Accuracy

We've hooked up the Analog Discovery 2 so that the waveform generator 1 is connected to channel 1 of the oscilloscope.

Compare the accuracy.

In the image above you can see captures of the datalogger reading the 0 value with and without calibration. You can see that with calibration, the zero is more accurate.


Step 13: If Necessary, Reset Calibration

If you are ever dissatisfied with the calibration of your Analog Discovery 2, you can reset the calibration to factory settings, or reset all values to zero by using the Reset menu in the Device Calibration window.


Step 14: Use Your Analog Discovery 2

Now that you've gone through the calibration process, you can begin taking advantage of the many features of the Analog Discovery 2.

Calibrated AD2.

To read more about those features, you can view the the reference manual here. There is also an extensive collection of projects on the Digilent Learn Site, as well as an entire curriculum called Real Analog written for the original Analog Discovery, but adaptable to the Analog Discovery 2.