• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 97 subscribers
  • Views 585 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

[AM5728] Supply power after PORz

Kaka
Guru 24520 points
Other Parts Discussed in Thread: AM5728

Hi TI Experts,

Please let me confirm the following question.

[Question]

When customer handle the PORz of AM5728, should they also reset the PMIC(i.e. re-supply the power for AM572x)?

If you have any questions, please let me know.

Best regards.

Kaka

  • 0
    TI__Guru**** 393215 points
    Hi,

    The AM572X datasheet section 5.5.2 gives the required voltages at boot time. If do reset only the AM57X device, voltages may fall out of boot time spec if the PMIC is not reset also. The AM572X EVM schematic shows that reset should be applied to PMIC NRESWARM pin too. Errata Advisory i862 discusses this.
  • 0 in reply to Biser Gatchev-XID
    Guru 24520 points

    Hi Biser,

    Thank you for your comments.
    I almost understand your comments. But I could not understand one point.
    You said " If do reset only the AM57X device, voltages may fall out of boot time spec if the PMIC is not reset also. ".

    Why does that voltage fall out of boot time spec by PORz deasserted? What is the kinds of specifications on boot time will fall out?

    I know that EVM connect the rstoutn pin to NRESWARM pin on PMIC. So, if PORz will happen, the rstoutn pin generate the signal and input the PMIC. Thus, the PMIC will start the OFFACT2 sequence. But if not connect the rstoutn pin to NRESWARM, all power domains for AM572x are satisfied the requirements. It seems that there is not any problem for power specification.

    If you have any questions, please let me know.
    Best regards.
    Kaka

  • 0 in reply to Kaka
    TI__Guru**** 393215 points
    Please see Table 5-7 in the datasheet. It gives separate values for voltages at boot time and after AVS is enabled. If you issue a reset during operation and reset only the processor, then the PMIC voltages will be left at their last state, which may be outside of requirements at reboot time.
  • 0 in reply to Biser Gatchev-XID
    Guru 24520 points
    I could understand them. Thank you for your kindly explanation.

    Best regards.
    Kaka