PLL not locked.

[lb8]

Hello, what's wrong with my device?

PLL not locked.

Unkown (sic) Scope chip id 0x9C.

Scope speed grade 0x45

CALSTATI 0x5

(see attached)

[JColvin]

Hi @lb8,

Have you used the Analog Discovery 2 previously? If so, did you use an external power supply, or through USB, or something else?

Usually what ends up producing that error is a damaged IC20 as described in this thread:

Thanks,
JColvin

[lb8]

HI, JColvin,

I've used the Discovery2 previously, never with a power supply though, always connected to a USB 3 port on my MacBook Pro, on a Thinkpad (Linux), and most recently on a Raspberry Pi 4.  It was previously suggested that my USB cable is "too weak", and since I may have lost the original one, I bought two replacements from Digilent.  But to no avail.

I didn't open the Discovery2, but I can see through the back cover, IC20 is physically intact, no crater (doesn't mean it's not blown).

What's the meaning of Unkown (sic) Scope chip id 0x9C?  I've had this issue since day one, the PLL lock is a new issue.

What should I do?  Send the unit back for repair?  

Regards,

-david

[DSA]

Is there a dispositive test of IC20?  How can I determine whether IC20 is functional or blown?

[JColvin]

Hi @lb8,

My understanding is that the Scope chip ID error is related to a powering issue (as per this thread, https://forum.digilentinc.com/topic/20686-device-configuration-failed-scope-chip-id-0x9c/), though in that particular thread I presume the replacement cables solved the issue since the customer didn't respond back. I don't personally know more details beyond that regarding the error, though I believe it prevents users from successfully using the board in WaveForms.

Digilent doesn't typically do repairs for our boards, but you can safely open up the Analog Discovery 2 case via the screws without voiding warranty if you wanted to check the board more thoroughly.

@attila might be able to give some more definitive information though.

Thanks,
JColvin

 

[lb8]

OK, but the Discovery 2 device always shows 5.1V available to it; and still this chip ID issue persists.  Let's see if we can determine whether it's IC20.  What's the failure mode when IC20 fails.  What test can we run to determine the health of IC20?

[lb8]

JColvin,

The "Unkown (sic) Scope chip id 0x9C" problem persists, it was first noticed "out of the box" (on MacBook Pro).  The USB cable replacement had no effect; and the voltage reported by the Discovery2, whenever I checked, was 5.0 - 5.1V.

If there's no further debugging to be done, I'd like to begin the RMA process for a replacement, this is after all an "out of the box" problem first reported on this forum.

Please advise.

-david

[JColvin]

Hi @lb8,

I do not know (or at least have not done any digging into finding out) a process to determine the functionality of IC20. Despite that, the Scope chip id 0x9C error from box opening is likely a manufacturing error.

To start the RMA process, you will need to fill out the Sales and Order Support form that is available on our website here: https://digilent.com/shipping-returns/#return-policy; our sales team will get any additional information they need from you after that. You can reference the conversion that we had here on this thread as evidence troubleshooting the issue.

Thanks,
JColvin

[lb8]

OK, thanks, I'll do that.