• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 2 answers
  • Subscribers 51 subscribers
  • Views 269 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CC2642R: CC26x2 Advisory Radio_Osc_01

paddu2017
Expert 2885 points
Part Number: CC2642R


Hi,

The errata sheet mentions about Increased Phase Noise When RCOSC_HF in Enabled (Advisory Radio_Osc_01).
We wonder how exactly this would effect the actual applications. Does it effect the RF performance or the BLE communication?
Should we expect drifts in the RF frequency?

And will this errata effect even if we use the SDK based examples?
Don't know if SDK based examples enable both XOSC_HF and RCOSC_HF at a time.

Best Regards
paddu

  • 0
    TI__Guru 58425 points
    Hi Paddu,

    In the overlap period, the phase noise would impact the TX quality, It would however not directly impact your BLE link. This could be an issue during certification as there is constraints in BLE spec on the TX quality.

    This would not add any drift in frequency. The situation where this happens is in the overlap where the RCOSC_HF is being calibrated which typically is done after the XOSC_HF is enabled in order to increase the start of time of the XOSC. This behavior could be expected in all SDK examples.
  • 0 in reply to IUsedToBeARealPerson (M-W)
    Expert 2885 points

    Hi M-W,

    Thank you so much for the detailed answer.

    I am sorry for asking this question again,

    This errata is about "increase in the Phase noise"
    so can we assume there won't be any effect on the RF performance like Frequency Accuracy/Initial Frequency Drift/Frequency Offset etc?
    and this phase noise would only reduce the signal quality and hence would increase the error rate of the communication.

    And as you mention if this could effect the BLE certification,
    should we wait for the next silicon version for the final application certification?

    According to my understanding as this issue(overlap) occurs only during the RCOSC_HF calibration,
    so the phase noise would be only during the startup and it won't be there during the normal runtime.

    Edit: The errata also mentions that "Depending on whether radio ROM patches are used or not"
    could you please let us know which version of the ROM patch we could use to avoid effect of this errata.

    Best Regards
    paddu

  • 0 in reply to paddu2017
    TI__Guru 58425 points
    Hi Paddu,

    You are right in your assumptions. As for radio ROM patches, this is PHY dependent and nothing you can select freely in the case of BLE.

    As for certification, this is the recommendation that you hold of with certification until the final silicon is available.
    As the current available silicon is prototype only and the characterization is ongoing, both hardware and software parameters are subject to change which would impact your certification.
  • 0 in reply to IUsedToBeARealPerson (M-W)
    Expert 2885 points
    Hi M-W,

    One additional question on this topic.

    As you mentioned about the "BLE spec on the TX quality" above,
    if possible could you please let us know which specification it would generally effect.
    We won't apply for the certification until the final silicon is available,
    but just in case we would like to know the BLE spec about TX quality.

    Best Regards
    paddu
  • 0 in reply to paddu2017
    TI__Guru 58425 points
    Hi Paddu,

    TX quality would include several points different specifications points.
    The point that would be affected by the phase noise would be the modulation characteristic spec.