• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 98 subscribers
  • Views 117 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.

AM4378: RTC disabled with RTC_KALDO_EN = HiZ

Amílcar Barca
Prodigy 70 points
Part Number: AM4378

Hi,

would there be a problem on the AM4378 if I connect ball CAP_VDD_RTC to + 1.1V power supply and I leave the RTC_KALDO_EN ball not connected (floating)?

Is it mandatory to connect the RTC_KALDO_EN pin to VSS or VDDS_RTC?

Does the RTC_KALDO_EN pin have an internal pullup or pulldown?

Regards.

  • +1
    TI__Guru 63125 points

    You can power the AM4378 RTC via the CAP_VDD_RTC pin with an external 1.1V power supply when RTC_KALDO_EN is connected to VDDS_RTC.

    The RTC_KALDO_EN input does not have an internal pull.  So you must connect this pin to VSS when using the internal LDO to source CAP_VDD_RTC, or to the same power source being used for VDDS_RTC when using an external 1.1V power supply to source CAP_VDD_RTC. The RTC_KALDO_EN input cannot be left to float to a unknown logic level.