[Analog Discovery troubleshooting]

Hi @attila

16 hours ago, attila said:

I was referring that connecting the ground wire of the AD device to a different voltage level (like to an external circuit which is supplied from a different source and grounding) could cause high current to pass the ground line toward the computer. This could burn the ferrite or protection diode in the AD.

In my case one of the AD2 boards is connected to a DUT (Device Under Test) and the DUT is powered via a separate bench top power supply. Also, the AD2 board is connected to a test server PC via USB cable and it has a separate external power supply connected to 5V DC input. Obviously, the test server PC, the bench top power supply and the AD2 power supply are powered from different power sockets under my desk (with a proper grounding I believe) and obviously the AD2 board's ground is connected to the DUT's ground. Correct me if I'm wrong, but I believe this should be a fairly common scenario for any measurement device like an oscilloscope or waveform generator. Could you please let me know if my setup can cause high current to pass the ground line toward the computer and damage an AD2 board? Thanks.

[Analog Discovery troubleshooting]

Hi @attila,

11 hours ago, attila said:

The 5V auxiliary supply should be protected for reverse polarity and up to 20V, scope inputs up to 50V, digital IOs 20V... Could it happen that device was connected to voltages or external sources exceeding any of these?

No, this device wasn't connected to voltages exceeding these values.

11 hours ago, attila said:

The AD ground is connected to computer ground through the USB cable. The earth/ground of different socket plugs could be wrongly wired and have high voltage difference. Connecting together circuits/equipment supplied from such plugs could blow up fuses, in case of AD the ferrites or protection diode toward the USB VCC/GND. Could it happen that the device ground was connected to another voltage level that the computer ground?

Not sure I understand the question, but this board was always connected to USB port either on my personal PC or on our test server PC.

 

Thanks,

Maks.

[Analog Discovery troubleshooting]

Hi @attila,

Thanks for your response, as you suggested I've tried to connect the board using different USB cable and through a powered USB hub (StarTech ST7300U3M) but without any success. Now I can see the following error:

We've purchased 6 boards in total so far and it's just this one board which gives us a bit of grief, all other boards are working fine. Is there a chance that we can replace that board somehow as this issue is blocking our testing at the moment? Thanks!

 

Regards,

Maks.

[Analog Discovery troubleshooting]

Hello,

For some reason my AD2 device stopped working today after a few months of good service. The board is powered via and external DC 5V/1.2A power supply and it is plugged into a USB socket at the back of my PC. I tried to connect it to two different PCs and tried to restart them both with the board disconnected.

Basically, when I open WaveForms 2015 ver. 3.5.4 (Windows 10 x64) it throws the following error:

And if I try to calibrate it:

And sometimes:

Also, factory calibration parameters are all zeroes:

When I disconnect the external power supply I'm getting a different error:

 

Thanks,

Maks.