• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 32 subscribers
  • Views 1164 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.

TM4C1231D5PM: Destroyed at writing to EEPROM while power supply drops

Jan Harman
Intellectual 455 points
Part Number: TM4C1231D5PM


Hi all,

many of TM4C have been destroyed, before I found out the reason. It could be caused, If mcu writes to EEPROM while power supply drops. If timing of writing hits certain point (range) in the voltage drop, writing cannot be stopped even if mcu detects voltage drop and mcu can destroy itself permanently. 

This is only for info.

Jan

  • 0
    Guru 27665 points
    Have you read the errata?

    The situation with EE is actually worse than you have portrayed it.

    Robert
  • 0
    TI__Guru**** 191906 points

    Hi Jan,

     Thanks for the information. Sorry to hear this happen. Which silicon revision do you have? I think you may have encountered errata MEM#03 or MEM#04. Hopefully you can apply the suggested workarounds.

  • 0
    Guru 117855 points

    Jan Harman said:
    It could be caused, If mcu writes to EEPROM while power supply drops.

    As this misfortune is rather prominently noted - should not you (and others) take readily available, "reasonable" safeguards - to prevent such "power supply drops?"

    A properly chosen & emplaced (and tested/verified) uninterruptible power supply should be deployed - especially in light of this "announced susceptibility!" 

    While the MCU seeks, "Kitchen Sink" status - it "too often" cannot match the performance or robustness of long existing, inexpensive, "purpose dedicated devices" - which suffer no such limitations!

  • 0 in reply to cb1_mobile
    Guru 27665 points

    cb1_mobile said:
    Jan Harman
    It could be caused, If mcu writes to EEPROM while power supply drops.

    As this misfortune is rather prominently noted - should not you (and others) take readily available, "reasonable" safeguards - to prevent such "power supply drops?"

    Well, I interpreted it as removing the power supply. That is hard to avoid especially since EE write times extend to seconds.

    cb1_mobile said:
    A properly chosen & emplaced (and tested/verified) uninterruptible power supply should be deployed - especially in light of this "announced susceptibility!" 

    Also note that resets cause the same problem including watchdog resets. This effectively renders the problem unavoidable for many systems except as you correctly note using a standard EE instead.

    Robert

  • 0 in reply to Robert Adsett
    Guru 117855 points

    Robert Adsett said:
    Resets - even watchdog resets ... (cause the same problem) ... effectively rendering the problem unavoidable - except as you correctly note - using a standard EE instead.

    Indeed - the "manifest destiny desires" of MCU makers (always expand capability - even when - and especially when - such expansion proves "LESS than ROBUST") leads to such issues!

    Could it be that simply: "Listing a feature as present" is more (vendor sought) than, "Insuring the feature meets/exceeds "normal standards of performance - to include robustness?"