Digital Discovery Calibration using WaveForms
While all Digilent Test and Measurement devices are factory calibrated, they can be recalibrated so that you can ensure that you are making the most accurate measurements possible.
- A reliable Digital Multimeter (DMM) (or individual ammeter and voltmeter instruments)
- DMM probes with grabber ends
- 30 Ohm high current resistor
- A Mac, Windows, or Linux computer with WaveForms installed
- If WaveForms is not yet installed, please review your device's Getting Started Guide for instructions, found via your device's Resource Center, linked from this wiki's Test and Measurement page.
Note: While all Digilent Test and Measurement devices are factory calibrated and can be calibrated by the user in WaveForms' Calibration Wizard, Digilent does not provide in-house or 3rd party calibration services.
1. Device Manager
Open Digilent's WaveForms application. At the top menu, click on the Settings menu option and then select Device Manager.
Once the Device Manager window opens, you can explore the available features.
In the top half of the window, the table lists the available devices. Plug in the Digital Discovery device to be used and it will appear in this list. Click on your Digital Discovery device to highlight the device.
Next, click the “Calibrate” tab to open the Device Calibration window.
2. Calibration Window
Select the “Calibrate” tab to view all of the items to be calibrated.
There is also the “File” menu where you can save or load an existing calibration file, and the “Reset” menu.
The Parameters and References tabs can also be seen. These are the values that define the existing calibration. It is highly recommended that you do NOT manually change these values. Instead, we will do a full calibration using the Calibration Wizard.
Note: The list of calibration items that can be performed, as seen in the screenshot to the right, is representative of Digital Discovery devices.
3. Device Calibration Wizard
To open the Device Calibration Wizard, click “Wizard” at the top of the Device Calibration window.
When the wizard opens, the start screen appears, as shown in the figure to the right. Instructions will be listed in the middle section during the calibration process. Click Next.
4. Digital Supply
The first step is to calibrate the digital supply. As shown in the image to the right, the Digital Discovery has two VIO and Ground pins pairs, on each 2×6 header. Set a DMM to measure voltage (or use a voltmeter) and connect it to a VIO and Ground pins pair, on the Digital Discovery.
WaveForms uses VDD for the VIO pin. Enter the voltage reading from the DMM (or voltmeter) in the “Measured:” field. Click Next and then enter a second voltage reading. Click Next again to continue.
5. Supply Ammeter
Connect a high current 30 Ohm resistor and a DMM set to measure amperage (or use an ammeter) to the VIO pin, on the Digital Discovery. Enter the measured current in the field and then press Next for additional measurements.
Caution: The resistor can get hot.
6. Done Calibrating!
To complete the calibration, disconnect the resistor and DMM (or ammeter) and click the Finish button to exit the calibration wizard.
7. Apply the Changes
In the Device Calibration window, click Apply and then Yes in the popup, to confirm the changes and return back to the Device Manager.
8. If Necessary, Reset Calibration
If you are ever dissatisfied with the calibration of your device, you can reset the calibration to factory settings, or reset all values to zero by using the Reset menu in the Device Calibration window.
9. Use Your Digilent Test and Measurement Device
Now that you've gone through the calibration process, you can begin taking advantage of the many features of your Digital Discovery.
For more guides on how to use your Digilent Test & Measurement Device, return to the device's Resource Center, linked from the Test and Measurement page of this wiki.
For more information on WaveForms visit the WaveForms Reference Manual.
For technical support, please visit the Test and Measurement section of the Digilent Forums.