TPS65982: Thunderbolt HD sometimes can not be detected.

daniel

Part Number: TPS65982

Hi Team,

Our product is a Thunderbolt daughter card that connect to a Thunderbolt HD storage, through a Type-C to Type-C cable.

We face an detect fail issue that sometimes the mother board can not recognize the thunderbolt HD.

We dump the CC log as detect OK (Pass) and Fail. Any check point can confirm if TPS65982 enter Thunderbolt mode? Or any critical difference between these two log that might cause this detect issue?

Please kindly help to review the log, and give us some comment.

Thanks

https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/138/TBT-Card_5F00_CC--log.7z

over 7 years ago

0 Eric Beljaars over 7 years ago

TI__Mastermind 36756 points

Hi Daniel,

From the PD logs, it looks like there is a disconnect event after the Thunderbolt mode entry. Can you monitor VBUS voltage and see if the voltage drops to 0V?

Thank you,
Eric

0 Peter Chen(ICP_FAE) over 7 years ago in reply to Eric Beljaars

TI__Intellectual 2480 points

Eric,

Are you saying the issue might be due to there might have a VBUS drop after the device already enter theThundersbolt mode? Is it might cause by CC comunication status change?

0 Eric Beljaars over 7 years ago in reply to Peter Chen(ICP_FAE)

TI__Mastermind 36756 points

Hi Peter, Daniel,

From the PD traces, the failing and passing case look identical. It is possible that this is not a PD controller issue and could be a TBT controller issue. In each of the traces we are correctly configuring and entering TBT mode and I don't see any issues in either trace. Another thing you can check is the contents of the Data Status register of the TPS65982. If it is the same in both passing and failing cases, I would suspect the issue is with the TBT controller.

If this answers your question, PLEASE select This resolved my issue

Thank you,

Eric

Interface

Interface forum

TPS65982: Thunderbolt HD sometimes can not be detected.