AD2 not detected - Unknown USB Device

[lindnerlars]

He guys, 

the same here, I have two AD2 devices, the first one stopped working a week ago and is not recognized by my Windows10 machine (see attached image). With the same machine, cable, software etc. the second AD2 is detected perfectly. 

I post this question as it is mentioned by JColvin to be able to start a RMA request:

 

Thanks everybody and with best wishes,

Lars

 

 

 

 

 

 

 

[attila]

Hi @lindnerlars

If the AD2 is detected as "unknown device device descriptor request failed" instead "USB Serial Converter" indicates cable contact problem or damaged USB controller.
Due to wear and tear, a cable may work with one device but not with another.
Please try a different cable, port, hub, computer.
If it still doesn't work, the device is probably damaged.

[lindnerlars]

He Attila, thank you very much for your quick answer. 

I have already used different cables, different USB ports and two different Windows 10 machines, but the result is the same. 🙄

 

 

 

 

 

[attila]

Hi @lindnerlars

The onboard ferrites could be damaged by short circuit, like connecting external supply to device GND/supplies, or the USB controller damaged by high USB voltage or short circuit.
If the device is out of warranty, here you can find troubleshooting/repair instructions:

 

[lindnerlars]

Hello attila, thank you for your answer.

Unfortunately I don't have much time for debugging or troubleshooting, I would like to open an RMA.

 

Thank you and with best wishes, 

Lars Lindner

 

Edited September 25, 2024 by lindnerlars

[attila]

For warranty and replacement contact the support.digilent @ ni.com specifying the Date of Purchase, Seller and Purchase Order/ Web order Number.

[lindnerlars]

Hello attila, thank you for your answer. 

Unfortunately, Digilent rejected my RMA and also stopped responding to my inquiries about whether it would be possible to purchase a new AD2 for a repair fee.

So today I measured the resistance of the ferrite beads and measured a value of almost 0. They show no external signs of damage or short circuits.

What would be the next steps?

 

Thanks and best regards, Lars

 

 

 

[attila]

Hi @lindnerlars

The next to verify would be the USB controller power rails:

 

[lindnerlars]

He Attila, thank you. 

Using this picture here (https://forum.digilent.com/topic/16046-ad2-short-circuit/?do=findComment&comment=39054), I have measured some values:

VPLL = 5V

VPHY = 5V

VCCCORE = 1.8V

VCCA = 1.5mV

VCCD = I am not sure, where to measure this

 

What would be the next steps?

 

Thanks and best regards, Lars

 

 

 

 

 

[attila]

Hi @lindnerlars

Probably the USB controller was damaged by high USB voltage.

 

[lindnerlars]

He Attila, Ok, thank you.

Do you mean, that maybe the FT232H was damaged? But how and why? I had used it to measure some PWM signals from a microcontroller, which doesn't output more than 5V TTL signal. 

So, how can I be sure that this controller is really broken? Is there another way to check? After confirming the defect, what do you recommend I do?

 

Thanks again and with best regards,

Lars

 

 

[attila]

Hi @lindnerlars

Check the controller rails marked in the earlier post. If these are not 3.3V and 1.8V at least the LDO in this IC burned out.
Bad USB hub supply could damage AD1,2 USB controller. IC20 can also be wrecked and so can other components.
Shorting AD ground to external supply rail could also damage the device, but in this case usually the ferrites burn out.

 

 

[lindnerlars]

Hey Attilla, thanks for your information.

Since I don't have much time for research, I would politely ask you to tell me exactly what I should test.

Thanks again for your help.

 

Best regards,
Lars

[attila]

On 10/28/2024 at 10:09 PM, attila said:

Probably the USB controller was damaged by high USB voltage.

 

[lindnerlars]

Hey Attilla, thanks for your reply.

How do I troubleshoot the USB Controller? The article you sent does not describe troubleshooting.

 

With best regards,
Lars

 

 

[lindnerlars]

Hey Attilla, I am really sorry to bother you again. 

How do I troubleshoot the USB Controller? The article you sent does not describe troubleshooting.

 

Thank you and with best regards,
Lars

[attila]

Hi @lindnerlars

See the following post:

 

[lindnerlars]

He Attila, ok. 

I will try replacing the USB controller. Please confirm that it's the following IC:

https://ftdichip.com/products/ft232hq/

, so that I will order the correct one.

 

Thank you and with greetings, Lars

 

 

 

 

 

 

[attila]

Yes, FT232HQ QFN48